[ANNOUNCE] v5.10-rc6-rt13v5.10-rc6-rt13-patches

Dear RT folks!

I'm pleased to announce the v5.10-rc6-rt13 patch set.

Changes since v5.10-rc6-rt12:

  - John's printk series was updated to his current status.

  - The notifier lock has been made a raw_spinlock_t to avoid a
    acquiring a sleeping lock in atomic context. Patch by Valentin
    Schneider.

  - The lock-lock in zswap lock was not properly initialized since
    v5.9-RT. This was noticed during the investigation of a z3fold
    related failure report Oleksandr Natalenko. According to Mike
    Galbraith this is still broken.

Known issues
     - It has been pointed out that due to changes to the printk code the
       internal buffer representation changed. This is only an issue if tools
       like `crash' are used to extract the printk buffer from a kernel memory
       image.

The delta patch against v5.10-rc6-rt12 is appended below and can be found here:

     https://cdn.kernel.org/pub/linux/kernel/projects/rt/5.10/incr/patch-5.10-rc6-rt12-rt13.patch.xz

You can get this release via the git tree at:

    git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git v5.10-rc6-rt13

The RT patch against v5.10-rc6 can be found here:

    https://cdn.kernel.org/pub/linux/kernel/projects/rt/5.10/older/patch-5.10-rc6-rt13.patch.xz

The split quilt queue is available at:

    https://cdn.kernel.org/pub/linux/kernel/projects/rt/5.10/older/patches-5.10-rc6-rt13.tar.xz

Sebastian

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

23 files changed, 1182 insertions, 866 deletions

diff --git a/patches/0001-printk-refactor-kmsg_dump_get_buffer.patch b/patches/0001-printk-refactor-kmsg_dump_get_buffer.patch
index 53fabc5d9437..219f71ec5104 100644
--- a/patches/0001-printk-refactor-kmsg_dump_get_buffer.patch
+++ b/patches/0001-printk-refactor-kmsg_dump_get_buffer.patch
@@ -1,6 +1,6 @@
 From: John Ogness <john.ogness@linutronix.de>
-Date: Wed, 14 Oct 2020 19:09:15 +0200
-Subject: [PATCH 01/15] printk: refactor kmsg_dump_get_buffer()
+Date: Mon, 30 Nov 2020 01:41:56 +0106
+Subject: [PATCH 01/16] printk: refactor kmsg_dump_get_buffer()
 
 kmsg_dump_get_buffer() requires nearly the same logic as
 syslog_print_all(), but uses different variable names and
@@ -85,7 +85,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	}
  
 -	/* last message in next interation */
-+	/* Keep track of the last message for the next interation. */
++	/* Keep track of the last message for the next iteration. */
  	next_seq = seq;
  
 -	/* actually read text into the buffer now */
diff --git a/patches/0008-printk-inline-log_output-log_store-in-vprintk_store.patch b/patches/0002-printk-inline-log_output-log_store-in-vprintk_store.patch
index f4cebbc4ca8f..0af56e5c7288 100644
--- a/patches/0008-printk-inline-log_output-log_store-in-vprintk_store.patch
+++ b/patches/0002-printk-inline-log_output-log_store-in-vprintk_store.patch
@@ -1,22 +1,21 @@
 From: John Ogness <john.ogness@linutronix.de>
-Date: Mon, 19 Oct 2020 16:40:26 +0206
-Subject: [PATCH 08/15] printk: inline log_output(),log_store() in
+Date: Mon, 30 Nov 2020 01:41:57 +0106
+Subject: [PATCH 02/16] printk: inline log_output(),log_store() in
  vprintk_store()
 
-In preparation for supporting atomic printing, inline log_output()
-and log_store() into vprintk_store(). This allows these
-sub-functions to more easily communicate if they have performed
-a finalized commit as well as the sequence number of that commit.
+In preparation for removing logbuf_lock, inline log_output()
+and log_store() into vprintk_store(). This will simplify dealing
+with the various code branches and fallbacks that are possible.
 
 Signed-off-by: John Ogness <john.ogness@linutronix.de>
 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 ---
- kernel/printk/printk.c |  141 +++++++++++++++++++++----------------------------
- 1 file changed, 63 insertions(+), 78 deletions(-)
+ kernel/printk/printk.c |  134 ++++++++++++++++++++-----------------------------
+ 1 file changed, 56 insertions(+), 78 deletions(-)
 
 --- a/kernel/printk/printk.c
 +++ b/kernel/printk/printk.c
-@@ -465,52 +465,6 @@ static void truncate_msg(u16 *text_len,
+@@ -491,52 +491,6 @@ static void truncate_msg(u16 *text_len,
  		*trunc_msg_len = 0;
  }
  
@@ -69,7 +68,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  int dmesg_restrict = IS_ENABLED(CONFIG_SECURITY_DMESG_RESTRICT);
  
  static int syslog_action_restricted(int type)
-@@ -2001,45 +1955,24 @@ static inline u32 printk_caller_id(void)
+@@ -1907,44 +1861,22 @@ static inline u32 printk_caller_id(void)
  		0x80000000 + raw_smp_processor_id();
  }
  
@@ -102,66 +101,59 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 -			 dev_info, text, text_len);
 -}
 -
+ /* Must be called under logbuf_lock. */
  int vprintk_store(int facility, int level,
  		  const struct dev_printk_info *dev_info,
  		  const char *fmt, va_list args)
  {
--	size_t text_len;
 +	const u32 caller_id = printk_caller_id();
+ 	static char textbuf[LOG_LINE_MAX];
+-	char *text = textbuf;
+-	size_t text_len;
 +	struct prb_reserved_entry e;
  	enum log_flags lflags = 0;
- 	unsigned long irqflags;
 +	struct printk_record r;
 +	u16 trunc_msg_len = 0;
- 	int sprint_id;
++	char *text = textbuf;
 +	u16 text_len;
 +	u64 ts_nsec;
-+	int ret = 0;
- 	char *text;
--	int ret;
-+	u64 seq;
 +
 +	ts_nsec = local_clock();
  
- 	/* No buffer is available if printk has recursed too much. */
- 	text = get_sprint_buf(&sprint_id, &irqflags);
-@@ -2083,8 +2016,60 @@ int vprintk_store(int facility, int leve
+ 	/*
+ 	 * The printf needs to come first; we need the syslog
+@@ -1983,7 +1915,53 @@ int vprintk_store(int facility, int leve
  	if (dev_info)
  		lflags |= LOG_NEWLINE;
  
--	ret = log_output(facility, level, lflags, dev_info, text, text_len);
+-	return log_output(facility, level, lflags, dev_info, text, text_len);
 +	if (lflags & LOG_CONT) {
 +		prb_rec_init_wr(&r, text_len);
 +		if (prb_reserve_in_last(&e, prb, &r, caller_id, LOG_LINE_MAX)) {
-+			seq = r.info->seq;
 +			memcpy(&r.text_buf[r.info->text_len], text, text_len);
 +			r.info->text_len += text_len;
++
 +			if (lflags & LOG_NEWLINE) {
 +				r.info->flags |= LOG_NEWLINE;
 +				prb_final_commit(&e);
 +			} else {
 +				prb_commit(&e);
 +			}
-+			ret = text_len;
-+			goto out;
++
++			return text_len;
 +		}
 +	}
 +
-+	/* Store it in the record log */
-+
 +	prb_rec_init_wr(&r, text_len);
-+
 +	if (!prb_reserve(&e, prb, &r)) {
 +		/* truncate the message if it is too long for empty buffer */
 +		truncate_msg(&text_len, &trunc_msg_len);
++
 +		prb_rec_init_wr(&r, text_len + trunc_msg_len);
-+		/* survive when the log buffer is too small for trunc_msg */
 +		if (!prb_reserve(&e, prb, &r))
-+			goto out;
++			return 0;
 +	}
 +
-+	seq = r.info->seq;
-+
 +	/* fill message */
 +	memcpy(&r.text_buf[0], text, text_len);
 +	if (trunc_msg_len)
@@ -174,16 +166,14 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 +	r.info->caller_id = caller_id;
 +	if (dev_info)
 +		memcpy(&r.info->dev_info, dev_info, sizeof(r.info->dev_info));
- 
-+	/* insert message */
-+	if ((lflags & LOG_CONT) || !(lflags & LOG_NEWLINE)) {
++
++	/* A message without a trailing newline can be continued. */
++	if (!(lflags & LOG_NEWLINE))
 +		prb_commit(&e);
-+	} else {
++	else
 +		prb_final_commit(&e);
-+	}
 +
-+	ret = text_len + trunc_msg_len;
-+out:
- 	put_sprint_buf(sprint_id, irqflags);
- 	return ret;
++	return (text_len + trunc_msg_len);
  }
+ 
+ asmlinkage int vprintk_emit(int facility, int level,
diff --git a/patches/0002-printk-use-buffer-pools-for-sprint-buffers.patch b/patches/0002-printk-use-buffer-pools-for-sprint-buffers.patch
deleted file mode 100644
index ee4c41875be3..000000000000
--- a/patches/0002-printk-use-buffer-pools-for-sprint-buffers.patch
+++ /dev/null
@@ -1,193 +0,0 @@
-From: John Ogness <john.ogness@linutronix.de>
-Date: Tue, 13 Oct 2020 22:57:55 +0200
-Subject: [PATCH 02/15] printk: use buffer pools for sprint buffers
-
-vprintk_store() is using a single static buffer as a temporary
-sprint buffer for the message text. This will not work once
-@logbuf_lock is removed. Replace the single static buffer with
-per-cpu and global pools.
-
-Each per-cpu pool is large enough to support a worse case of 2
-contexts (non-NMI and NMI).
-
-To support printk() recursion and printk() calls before per-cpu
-variables are ready, an extra/fallback global pool of 2 contexts is
-available.
-
-Signed-off-by: John Ogness <john.ogness@linutronix.de>
-Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
----
- kernel/printk/printk.c |  141 +++++++++++++++++++++++++++++++++++++++++++++++--
- 1 file changed, 137 insertions(+), 4 deletions(-)
-
---- a/kernel/printk/printk.c
-+++ b/kernel/printk/printk.c
-@@ -1704,6 +1704,129 @@ SYSCALL_DEFINE3(syslog, int, type, char
- }
- 
- /*
-+ * The per-cpu sprint buffers are used with interrupts disabled, so each CPU
-+ * only requires 2 buffers: for non-NMI and NMI contexts. Recursive printk()
-+ * calls are handled by the global sprint buffers.
-+ */
-+#define SPRINT_CTX_DEPTH 2
-+
-+/* Static sprint buffers for early boot (only 1 CPU) and recursion. */
-+static DECLARE_BITMAP(sprint_global_buffer_map, SPRINT_CTX_DEPTH);
-+static char sprint_global_buffer[SPRINT_CTX_DEPTH][PREFIX_MAX + LOG_LINE_MAX];
-+
-+struct sprint_buffers {
-+	char		buf[SPRINT_CTX_DEPTH][PREFIX_MAX + LOG_LINE_MAX];
-+	atomic_t	index;
-+};
-+
-+static DEFINE_PER_CPU(struct sprint_buffers, percpu_sprint_buffers);
-+
-+/*
-+ * Acquire an unused buffer, returning its index. If no buffer is
-+ * available, @count is returned.
-+ */
-+static int _get_sprint_buf(unsigned long *map, int count)
-+{
-+	int index;
-+
-+	do {
-+		index = find_first_zero_bit(map, count);
-+		if (index == count)
-+			break;
-+	/*
-+	 * Guarantee map changes are ordered for the other CPUs.
-+	 * Pairs with clear_bit() in _put_sprint_buf().
-+	 */
-+	} while (test_and_set_bit(index, map));
-+
-+	return index;
-+}
-+
-+/* Mark the buffer @index as unused. */
-+static void _put_sprint_buf(unsigned long *map, unsigned int count, unsigned int index)
-+{
-+	/*
-+	 * Guarantee map changes are ordered for the other CPUs.
-+	 * Pairs with test_and_set_bit() in _get_sprint_buf().
-+	 */
-+	clear_bit(index, map);
-+}
-+
-+/*
-+ * Get a buffer sized PREFIX_MAX+LOG_LINE_MAX for sprinting. On success, @id
-+ * is set and interrupts are disabled. @id is used to put back the buffer.
-+ *
-+ * @id is non-negative for per-cpu buffers, negative for global buffers.
-+ */
-+static char *get_sprint_buf(int *id, unsigned long *flags)
-+{
-+	struct sprint_buffers *bufs;
-+	unsigned int index;
-+	unsigned int cpu;
-+
-+	local_irq_save(*flags);
-+	cpu = get_cpu();
-+
-+	if (printk_percpu_data_ready()) {
-+
-+		/*
-+		 * First try with per-cpu pool. Note that the last
-+		 * buffer is reserved for NMI context.
-+		 */
-+		bufs = per_cpu_ptr(&percpu_sprint_buffers, cpu);
-+		index = atomic_read(&bufs->index);
-+		if (index < (SPRINT_CTX_DEPTH - 1) ||
-+		    (in_nmi() && index < SPRINT_CTX_DEPTH)) {
-+			atomic_set(&bufs->index, index + 1);
-+			*id = cpu;
-+			return &bufs->buf[index][0];
-+		}
-+	}
-+
-+	/*
-+	 * Fallback to global pool.
-+	 *
-+	 * The global pool will only ever be used if per-cpu data is not ready
-+	 * yet or printk recurses. Recursion will not occur unless printk is
-+	 * having internal issues.
-+	 */
-+	index = _get_sprint_buf(sprint_global_buffer_map, SPRINT_CTX_DEPTH);
-+	if (index != SPRINT_CTX_DEPTH) {
-+		/* Convert to global buffer representation. */
-+		*id = -index - 1;
-+		return &sprint_global_buffer[index][0];
-+	}
-+
-+	/* Failed to get a buffer. */
-+	put_cpu();
-+	local_irq_restore(*flags);
-+	return NULL;
-+}
-+
-+/* Put back an sprint buffer and restore interrupts. */
-+static void put_sprint_buf(int id, unsigned long flags)
-+{
-+	struct sprint_buffers *bufs;
-+	unsigned int index;
-+	unsigned int cpu;
-+
-+	if (id >= 0) {
-+		cpu = id;
-+		bufs = per_cpu_ptr(&percpu_sprint_buffers, cpu);
-+		index = atomic_read(&bufs->index);
-+		atomic_set(&bufs->index, index - 1);
-+	} else {
-+		/* Convert from global buffer representation. */
-+		index = -id - 1;
-+		_put_sprint_buf(sprint_global_buffer_map,
-+				SPRINT_CTX_DEPTH, index);
-+	}
-+
-+	put_cpu();
-+	local_irq_restore(flags);
-+}
-+
-+/*
-  * Special console_lock variants that help to reduce the risk of soft-lockups.
-  * They allow to pass console_lock to another printk() call using a busy wait.
-  */
-@@ -1941,16 +2064,23 @@ int vprintk_store(int facility, int leve
- 		  const struct dev_printk_info *dev_info,
- 		  const char *fmt, va_list args)
- {
--	static char textbuf[LOG_LINE_MAX];
--	char *text = textbuf;
- 	size_t text_len;
- 	enum log_flags lflags = 0;
-+	unsigned long irqflags;
-+	int sprint_id;
-+	char *text;
-+	int ret;
-+
-+	/* No buffer is available if printk has recursed too much. */
-+	text = get_sprint_buf(&sprint_id, &irqflags);
-+	if (!text)
-+		return 0;
- 
- 	/*
- 	 * The printf needs to come first; we need the syslog
- 	 * prefix which might be passed-in as a parameter.
- 	 */
--	text_len = vscnprintf(text, sizeof(textbuf), fmt, args);
-+	text_len = vscnprintf(text, LOG_LINE_MAX, fmt, args);
- 
- 	/* mark and strip a trailing newline */
- 	if (text_len && text[text_len-1] == '\n') {
-@@ -1983,7 +2113,10 @@ int vprintk_store(int facility, int leve
- 	if (dev_info)
- 		lflags |= LOG_NEWLINE;
- 
--	return log_output(facility, level, lflags, dev_info, text, text_len);
-+	ret = log_output(facility, level, lflags, dev_info, text, text_len);
-+
-+	put_sprint_buf(sprint_id, irqflags);
-+	return ret;
- }
- 
- asmlinkage int vprintk_emit(int facility, int level,
diff --git a/patches/0003-printk-change-clear_seq-to-atomic64_t.patch b/patches/0003-printk-change-clear_seq-to-atomic64_t.patch
index d29d83360af9..0eaf077e7e1d 100644
--- a/patches/0003-printk-change-clear_seq-to-atomic64_t.patch
+++ b/patches/0003-printk-change-clear_seq-to-atomic64_t.patch
@@ -1,6 +1,6 @@
 From: John Ogness <john.ogness@linutronix.de>
-Date: Tue, 13 Oct 2020 23:19:35 +0200
-Subject: [PATCH 03/15] printk: change @clear_seq to atomic64_t
+Date: Mon, 30 Nov 2020 01:41:58 +0106
+Subject: [PATCH 03/16] printk: change @clear_seq to atomic64_t
 
 Currently @clear_seq access is protected by @logbuf_lock. Once
 @logbuf_lock is removed some other form of synchronization will be
@@ -24,7 +24,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  
  #ifdef CONFIG_PRINTK_CALLER
  #define PREFIX_MAX		48
-@@ -843,7 +843,7 @@ static loff_t devkmsg_llseek(struct file
+@@ -797,7 +797,7 @@ static loff_t devkmsg_llseek(struct file
  		 * like issued by 'dmesg -c'. Reading /dev/kmsg itself
  		 * changes no global state, and does not clear anything.
  		 */
@@ -33,7 +33,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  		break;
  	case SEEK_END:
  		/* after the last record */
-@@ -960,6 +960,9 @@ void log_buf_vmcoreinfo_setup(void)
+@@ -914,6 +914,9 @@ void log_buf_vmcoreinfo_setup(void)
  	 * parse it and detect any changes to structure down the line.
  	 */
  
@@ -43,7 +43,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	VMCOREINFO_STRUCT_SIZE(printk_ringbuffer);
  	VMCOREINFO_OFFSET(printk_ringbuffer, desc_ring);
  	VMCOREINFO_OFFSET(printk_ringbuffer, text_data_ring);
-@@ -1522,6 +1525,7 @@ static int syslog_print_all(char __user
+@@ -1476,6 +1479,7 @@ static int syslog_print_all(char __user
  	struct printk_info info;
  	unsigned int line_count;
  	struct printk_record r;
@@ -51,7 +51,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	char *text;
  	int len = 0;
  	u64 seq;
-@@ -1533,15 +1537,17 @@ static int syslog_print_all(char __user
+@@ -1487,15 +1491,17 @@ static int syslog_print_all(char __user
  
  	time = printk_time;
  	logbuf_lock_irq();
@@ -71,7 +71,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  		if (len <= size)
  			break;
  		len -= get_record_print_text_size(&info, line_count, true, time);
-@@ -1572,7 +1578,7 @@ static int syslog_print_all(char __user
+@@ -1526,7 +1532,7 @@ static int syslog_print_all(char __user
  	}
  
  	if (clear)
@@ -80,7 +80,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	logbuf_unlock_irq();
  
  	kfree(text);
-@@ -1582,7 +1588,7 @@ static int syslog_print_all(char __user
+@@ -1536,7 +1542,7 @@ static int syslog_print_all(char __user
  static void syslog_clear(void)
  {
  	logbuf_lock_irq();
@@ -89,7 +89,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	logbuf_unlock_irq();
  }
  
-@@ -3355,7 +3361,7 @@ void kmsg_dump(enum kmsg_dump_reason rea
+@@ -3200,7 +3206,7 @@ void kmsg_dump(enum kmsg_dump_reason rea
  		dumper->active = true;
  
  		logbuf_lock_irqsave(flags);
@@ -98,7 +98,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  		dumper->next_seq = prb_next_seq(prb);
  		logbuf_unlock_irqrestore(flags);
  
-@@ -3563,7 +3569,7 @@ EXPORT_SYMBOL_GPL(kmsg_dump_get_buffer);
+@@ -3408,7 +3414,7 @@ EXPORT_SYMBOL_GPL(kmsg_dump_get_buffer);
   */
  void kmsg_dump_rewind_nolock(struct kmsg_dumper *dumper)
  {
diff --git a/patches/0004-printk-remove-logbuf_lock-add-syslog_lock.patch b/patches/0004-printk-remove-logbuf_lock-add-syslog_lock.patch
index 2ee099289033..b9cd36838148 100644
--- a/patches/0004-printk-remove-logbuf_lock-add-syslog_lock.patch
+++ b/patches/0004-printk-remove-logbuf_lock-add-syslog_lock.patch
@@ -1,6 +1,6 @@
 From: John Ogness <john.ogness@linutronix.de>
-Date: Wed, 14 Oct 2020 19:06:12 +0200
-Subject: [PATCH 04/15] printk: remove logbuf_lock, add syslog_lock
+Date: Mon, 30 Nov 2020 01:41:59 +0106
+Subject: [PATCH 04/16] printk: remove logbuf_lock, add syslog_lock
 
 Since the ringbuffer is lockless, there is no need for it to be
 protected by @logbuf_lock. Remove @logbuf_lock.
@@ -15,14 +15,33 @@ protect these.
 @console_seq, @exclusive_console_stop_seq, @console_dropped are
 protected by @console_lock.
 
+Without @logbuf_lock it is no longer possible to use the single
+static buffer for temporarily sprint'ing the message. Instead,
+use vsnprintf() to determine the length and perform the real
+vscnprintf() using the area reserved from the ringbuffer. This
+leads to suboptimal packing of the message data, but will
+result in less wasted storage than multiple per-cpu buffers to
+support lockless temporary sprint'ing.
+
 Signed-off-by: John Ogness <john.ogness@linutronix.de>
 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 ---
- kernel/printk/internal.h    |    4 -
- kernel/printk/printk.c      |  151 +++++++++++---------------------------------
- kernel/printk/printk_safe.c |   18 -----
- 3 files changed, 42 insertions(+), 131 deletions(-)
+ include/linux/printk.h      |    1 
+ kernel/printk/internal.h    |    4 
+ kernel/printk/printk.c      |  285 +++++++++++++++++++++++---------------------
+ kernel/printk/printk_safe.c |   18 --
+ 4 files changed, 157 insertions(+), 151 deletions(-)
 
+--- a/include/linux/printk.h
++++ b/include/linux/printk.h
+@@ -45,6 +45,7 @@ static inline const char *printk_skip_he
+ }
+ 
+ #define CONSOLE_EXT_LOG_MAX	8192
++#define CONSOLE_LOG_MAX		1024
+ 
+ /* printk's without a loglevel use this.. */
+ #define MESSAGE_LOGLEVEL_DEFAULT CONFIG_MESSAGE_LOGLEVEL_DEFAULT
 --- a/kernel/printk/internal.h
 +++ b/kernel/printk/internal.h
 @@ -12,8 +12,6 @@
@@ -45,7 +64,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
   */
 --- a/kernel/printk/printk.c
 +++ b/kernel/printk/printk.c
-@@ -355,48 +355,22 @@ enum log_flags {
+@@ -355,48 +355,18 @@ enum log_flags {
  	LOG_CONT	= 8,	/* text is a fragment of a continuation line */
  };
  
@@ -84,11 +103,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 -		printk_safe_exit_irqrestore(flags);	\
 -	} while (0)
 +/* The syslog_lock protects syslog_* variables. */
-+DEFINE_RAW_SPINLOCK(syslog_lock);
-+#define syslog_lock_irq() raw_spin_lock_irq(&syslog_lock)
-+#define syslog_unlock_irq() raw_spin_unlock_irq(&syslog_lock)
-+#define syslog_lock_irqsave(flags) raw_spin_lock_irqsave(&syslog_lock, flags)
-+#define syslog_unlock_irqrestore(flags) raw_spin_unlock_irqrestore(&syslog_lock, flags)
++static DEFINE_SPINLOCK(syslog_lock);
  
  #ifdef CONFIG_PRINTK
  DECLARE_WAIT_QUEUE_HEAD(log_wait);
@@ -102,7 +117,16 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  /* the next printk record to write to the console */
  static u64 console_seq;
  static u64 exclusive_console_stop_seq;
-@@ -766,27 +740,22 @@ static ssize_t devkmsg_read(struct file
+@@ -410,7 +380,7 @@ static atomic64_t clear_seq = ATOMIC64_I
+ #else
+ #define PREFIX_MAX		32
+ #endif
+-#define LOG_LINE_MAX		(1024 - PREFIX_MAX)
++#define LOG_LINE_MAX		(CONSOLE_LOG_MAX - PREFIX_MAX)
+ 
+ #define LOG_LEVEL(v)		((v) & 0x07)
+ #define LOG_FACILITY(v)		((v) >> 3 & 0xff)
+@@ -720,27 +690,22 @@ static ssize_t devkmsg_read(struct file
  	if (ret)
  		return ret;
  
@@ -130,7 +154,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  		goto out;
  	}
  
-@@ -796,7 +765,6 @@ static ssize_t devkmsg_read(struct file
+@@ -750,7 +715,6 @@ static ssize_t devkmsg_read(struct file
  				  &r->info->dev_info);
  
  	user->seq = r->info->seq + 1;
@@ -138,7 +162,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  
  	if (len > count) {
  		ret = -EINVAL;
-@@ -831,7 +799,6 @@ static loff_t devkmsg_llseek(struct file
+@@ -785,7 +749,6 @@ static loff_t devkmsg_llseek(struct file
  	if (offset)
  		return -ESPIPE;
  
@@ -146,7 +170,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	switch (whence) {
  	case SEEK_SET:
  		/* the first record */
-@@ -852,7 +819,6 @@ static loff_t devkmsg_llseek(struct file
+@@ -806,7 +769,6 @@ static loff_t devkmsg_llseek(struct file
  	default:
  		ret = -EINVAL;
  	}
@@ -154,7 +178,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	return ret;
  }
  
-@@ -866,7 +832,6 @@ static __poll_t devkmsg_poll(struct file
+@@ -820,7 +782,6 @@ static __poll_t devkmsg_poll(struct file
  
  	poll_wait(file, &log_wait, wait);
  
@@ -162,7 +186,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	if (prb_read_valid(prb, user->seq, NULL)) {
  		/* return error when data has vanished underneath us */
  		if (user->seq < prb_first_valid_seq(prb))
-@@ -874,7 +839,6 @@ static __poll_t devkmsg_poll(struct file
+@@ -828,7 +789,6 @@ static __poll_t devkmsg_poll(struct file
  		else
  			ret = EPOLLIN|EPOLLRDNORM;
  	}
@@ -170,7 +194,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  
  	return ret;
  }
-@@ -907,9 +871,7 @@ static int devkmsg_open(struct inode *in
+@@ -861,9 +821,7 @@ static int devkmsg_open(struct inode *in
  	prb_rec_init_rd(&user->record, &user->info,
  			&user->text_buf[0], sizeof(user->text_buf));
  
@@ -180,7 +204,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  
  	file->private_data = user;
  	return 0;
-@@ -1117,7 +1079,6 @@ void __init setup_log_buf(int early)
+@@ -1071,7 +1029,6 @@ void __init setup_log_buf(int early)
  	struct printk_record r;
  	size_t new_descs_size;
  	size_t new_infos_size;
@@ -188,7 +212,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	char *new_log_buf;
  	unsigned int free;
  	u64 seq;
-@@ -1175,8 +1136,6 @@ void __init setup_log_buf(int early)
+@@ -1129,8 +1086,6 @@ void __init setup_log_buf(int early)
  		 new_descs, ilog2(new_descs_count),
  		 new_infos);
  
@@ -197,7 +221,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	log_buf_len = new_log_buf_len;
  	log_buf = new_log_buf;
  	new_log_buf_len = 0;
-@@ -1192,8 +1151,6 @@ void __init setup_log_buf(int early)
+@@ -1146,8 +1101,6 @@ void __init setup_log_buf(int early)
  	 */
  	prb = &printk_rb_dynamic;
  
@@ -206,28 +230,28 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	if (seq != prb_next_seq(&printk_rb_static)) {
  		pr_err("dropped %llu messages\n",
  		       prb_next_seq(&printk_rb_static) - seq);
-@@ -1469,9 +1426,9 @@ static int syslog_print(char __user *buf
+@@ -1423,9 +1376,9 @@ static int syslog_print(char __user *buf
  		size_t n;
  		size_t skip;
  
 -		logbuf_lock_irq();
-+		syslog_lock_irq();
++		spin_lock_irq(&syslog_lock);
  		if (!prb_read_valid(prb, syslog_seq, &r)) {
 -			logbuf_unlock_irq();
-+			syslog_unlock_irq();
++			spin_unlock_irq(&syslog_lock);
  			break;
  		}
  		if (r.info->seq != syslog_seq) {
-@@ -1500,7 +1457,7 @@ static int syslog_print(char __user *buf
+@@ -1454,7 +1407,7 @@ static int syslog_print(char __user *buf
  			syslog_partial += n;
  		} else
  			n = 0;
 -		logbuf_unlock_irq();
-+		syslog_unlock_irq();
++		spin_unlock_irq(&syslog_lock);
  
  		if (!n)
  			break;
-@@ -1525,6 +1482,7 @@ static int syslog_print_all(char __user
+@@ -1479,6 +1432,7 @@ static int syslog_print_all(char __user
  	struct printk_info info;
  	unsigned int line_count;
  	struct printk_record r;
@@ -235,7 +259,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	u64 clr_seq;
  	char *text;
  	int len = 0;
-@@ -1536,19 +1494,30 @@ static int syslog_print_all(char __user
+@@ -1490,19 +1444,30 @@ static int syslog_print_all(char __user
  		return -ENOMEM;
  
  	time = printk_time;
@@ -269,7 +293,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  			break;
  		len -= get_record_print_text_size(&info, line_count, true, time);
  	}
-@@ -1566,12 +1535,10 @@ static int syslog_print_all(char __user
+@@ -1520,12 +1485,10 @@ static int syslog_print_all(char __user
  			break;
  		}
  
@@ -282,7 +306,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  
  		if (len < 0)
  			break;
-@@ -1579,7 +1546,6 @@ static int syslog_print_all(char __user
+@@ -1533,7 +1496,6 @@ static int syslog_print_all(char __user
  
  	if (clear)
  		atomic64_set(&clear_seq, seq);
@@ -290,7 +314,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  
  	kfree(text);
  	return len;
-@@ -1587,9 +1553,7 @@ static int syslog_print_all(char __user
+@@ -1541,9 +1503,7 @@ static int syslog_print_all(char __user
  
  static void syslog_clear(void)
  {
@@ -300,7 +324,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  }
  
  int do_syslog(int type, char __user *buf, int len, int source)
-@@ -1597,6 +1561,7 @@ int do_syslog(int type, char __user *buf
+@@ -1551,6 +1511,7 @@ int do_syslog(int type, char __user *buf
  	bool clear = false;
  	static int saved_console_loglevel = LOGLEVEL_DEFAULT;
  	int error;
@@ -308,46 +332,249 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  
  	error = check_syslog_permissions(type, source);
  	if (error)
-@@ -1614,8 +1579,11 @@ int do_syslog(int type, char __user *buf
+@@ -1568,8 +1529,11 @@ int do_syslog(int type, char __user *buf
  			return 0;
  		if (!access_ok(buf, len))
  			return -EFAULT;
-+		syslog_lock_irq();
++		spin_lock_irq(&syslog_lock);
 +		seq = syslog_seq;
-+		syslog_unlock_irq();
++		spin_unlock_irq(&syslog_lock);
  		error = wait_event_interruptible(log_wait,
 -				prb_read_valid(prb, syslog_seq, NULL));
 +				prb_read_valid(prb, seq, NULL));
  		if (error)
  			return error;
  		error = syslog_print(buf, len);
-@@ -1663,7 +1631,7 @@ int do_syslog(int type, char __user *buf
+@@ -1617,7 +1581,7 @@ int do_syslog(int type, char __user *buf
  		break;
  	/* Number of chars in the log buffer */
  	case SYSLOG_ACTION_SIZE_UNREAD:
 -		logbuf_lock_irq();
-+		syslog_lock_irq();
++		spin_lock_irq(&syslog_lock);
  		if (syslog_seq < prb_first_valid_seq(prb)) {
  			/* messages are gone, move to first one */
  			syslog_seq = prb_first_valid_seq(prb);
-@@ -1690,7 +1658,7 @@ int do_syslog(int type, char __user *buf
+@@ -1644,7 +1608,7 @@ int do_syslog(int type, char __user *buf
  			}
  			error -= syslog_partial;
  		}
 -		logbuf_unlock_irq();
-+		syslog_unlock_irq();
++		spin_unlock_irq(&syslog_lock);
  		break;
  	/* Size of the log buffer */
  	case SYSLOG_ACTION_SIZE_BUFFER:
-@@ -2065,7 +2033,6 @@ static size_t log_output(int facility, i
- 			 dev_info, text, text_len);
+@@ -1847,6 +1811,65 @@ static void call_console_drivers(const c
+ 	}
+ }
+ 
++#ifdef CONFIG_PRINTK_NMI
++#define NUM_RECURSION_CTX 2
++#else
++#define NUM_RECURSION_CTX 1
++#endif
++
++struct printk_recursion {
++	char	count[NUM_RECURSION_CTX];
++};
++
++static DEFINE_PER_CPU(struct printk_recursion, percpu_printk_recursion);
++static char printk_recursion_count[NUM_RECURSION_CTX];
++
++static char *get_printk_count(void)
++{
++	struct printk_recursion *rec;
++	char *count;
++
++	if (!printk_percpu_data_ready()) {
++		count = &printk_recursion_count[0];
++	} else {
++		rec = this_cpu_ptr(&percpu_printk_recursion);
++
++		count = &rec->count[0];
++	}
++
++#ifdef CONFIG_PRINTK_NMI
++	if (in_nmi())
++		count++;
++#endif
++
++	return count;
++}
++
++static bool printk_enter(unsigned long *flags)
++{
++	char *count;
++
++	local_irq_save(*flags);
++	count = get_printk_count();
++	/* Only 1 level of recursion allowed. */
++	if (*count > 1) {
++		local_irq_restore(*flags);
++		return false;
++	}
++	(*count)++;
++
++	return true;
++}
++
++static void printk_exit(unsigned long flags)
++{
++	char *count;
++
++	count = get_printk_count();
++	(*count)--;
++	local_irq_restore(flags);
++}
++
+ int printk_delay_msec __read_mostly;
+ 
+ static inline void printk_delay(void)
+@@ -1867,40 +1890,75 @@ static inline u32 printk_caller_id(void)
+ 		0x80000000 + raw_smp_processor_id();
  }
  
 -/* Must be called under logbuf_lock. */
++static u16 printk_sprint(char *text, u16 size, int facility, enum log_flags *lflags,
++			 const char *fmt, va_list args)
++{
++	char *orig_text = text;
++	u16 text_len;
++
++	text_len = vscnprintf(text, size, fmt, args);
++
++	/* Mark and strip a trailing newline. */
++	if (text_len && text[text_len - 1] == '\n') {
++		text_len--;
++		*lflags |= LOG_NEWLINE;
++	}
++
++	/* Strip kernel syslog prefix. */
++	if (facility == 0) {
++		while (text_len >= 2 && printk_get_level(text)) {
++			text_len -= 2;
++			text += 2;
++		}
++
++		if (text != orig_text)
++			memmove(orig_text, text, text_len);
++	}
++
++	return text_len;
++}
++
++__printf(4, 0)
  int vprintk_store(int facility, int level,
  		  const struct dev_printk_info *dev_info,
  		  const char *fmt, va_list args)
-@@ -2131,7 +2098,6 @@ asmlinkage int vprintk_emit(int facility
+ {
+ 	const u32 caller_id = printk_caller_id();
+-	static char textbuf[LOG_LINE_MAX];
+ 	struct prb_reserved_entry e;
+ 	enum log_flags lflags = 0;
+ 	struct printk_record r;
++	unsigned long irqflags;
+ 	u16 trunc_msg_len = 0;
+-	char *text = textbuf;
++	char lvlbuf[8];
++	va_list args2;
+ 	u16 text_len;
++	int ret = 0;
+ 	u64 ts_nsec;
+ 
+ 	ts_nsec = local_clock();
+ 
++	if (!printk_enter(&irqflags))
++		return 0;
++
++	va_copy(args2, args);
++
+ 	/*
+ 	 * The printf needs to come first; we need the syslog
+ 	 * prefix which might be passed-in as a parameter.
+ 	 */
+-	text_len = vscnprintf(text, sizeof(textbuf), fmt, args);
++	text_len = vsnprintf(&lvlbuf[0], sizeof(lvlbuf), fmt, args) + 1;
++	if (text_len > CONSOLE_LOG_MAX)
++		text_len = CONSOLE_LOG_MAX;
+ 
+-	/* mark and strip a trailing newline */
+-	if (text_len && text[text_len-1] == '\n') {
+-		text_len--;
+-		lflags |= LOG_NEWLINE;
+-	}
+-
+-	/* strip kernel syslog prefix and extract log level or control flags */
++	/* Extract log level or control flags. */
+ 	if (facility == 0) {
+ 		int kern_level;
++		int i;
+ 
+-		while ((kern_level = printk_get_level(text)) != 0) {
++		for (i = 0; i < sizeof(lvlbuf); i += 2) {
++			kern_level = printk_get_level(&lvlbuf[i]);
++			if (!kern_level)
++				break;
+ 			switch (kern_level) {
+ 			case '0' ... '7':
+ 				if (level == LOGLEVEL_DEFAULT)
+@@ -1909,9 +1967,6 @@ int vprintk_store(int facility, int leve
+ 			case 'c':	/* KERN_CONT */
+ 				lflags |= LOG_CONT;
+ 			}
+-
+-			text_len -= 2;
+-			text += 2;
+ 		}
+ 	}
+ 
+@@ -1924,7 +1979,8 @@ int vprintk_store(int facility, int leve
+ 	if (lflags & LOG_CONT) {
+ 		prb_rec_init_wr(&r, text_len);
+ 		if (prb_reserve_in_last(&e, prb, &r, caller_id, LOG_LINE_MAX)) {
+-			memcpy(&r.text_buf[r.info->text_len], text, text_len);
++			text_len = printk_sprint(&r.text_buf[r.info->text_len], text_len,
++						 facility, &lflags, fmt, args2);
+ 			r.info->text_len += text_len;
+ 
+ 			if (lflags & LOG_NEWLINE) {
+@@ -1934,7 +1990,8 @@ int vprintk_store(int facility, int leve
+ 				prb_commit(&e);
+ 			}
+ 
+-			return text_len;
++			ret = text_len;
++			goto out;
+ 		}
+ 	}
+ 
+@@ -1945,11 +2002,11 @@ int vprintk_store(int facility, int leve
+ 
+ 		prb_rec_init_wr(&r, text_len + trunc_msg_len);
+ 		if (!prb_reserve(&e, prb, &r))
+-			return 0;
++			goto out;
+ 	}
+ 
+ 	/* fill message */
+-	memcpy(&r.text_buf[0], text, text_len);
++	text_len = printk_sprint(&r.text_buf[0], text_len, facility, &lflags, fmt, args2);
+ 	if (trunc_msg_len)
+ 		memcpy(&r.text_buf[text_len], trunc_msg, trunc_msg_len);
+ 	r.info->text_len = text_len + trunc_msg_len;
+@@ -1967,7 +2024,11 @@ int vprintk_store(int facility, int leve
+ 	else
+ 		prb_final_commit(&e);
+ 
+-	return (text_len + trunc_msg_len);
++	ret = text_len + trunc_msg_len;
++out:
++	va_end(args2);
++	printk_exit(irqflags);
++	return ret;
+ }
+ 
+ asmlinkage int vprintk_emit(int facility, int level,
+@@ -1976,7 +2037,6 @@ asmlinkage int vprintk_emit(int facility
  {
  	int printed_len;
  	bool in_sched = false;
@@ -355,7 +582,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  
  	/* Suppress unimportant messages after panic happens */
  	if (unlikely(suppress_printk))
-@@ -2146,9 +2112,7 @@ asmlinkage int vprintk_emit(int facility
+@@ -1991,9 +2051,7 @@ asmlinkage int vprintk_emit(int facility
  	printk_delay();
  
  	/* This stops the holder of console_sem just where we want him */
@@ -365,7 +592,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  
  	/* If called from the scheduler, we can not call up(). */
  	if (!in_sched) {
-@@ -2580,7 +2544,6 @@ void console_unlock(void)
+@@ -2425,7 +2483,6 @@ void console_unlock(void)
  		size_t len;
  
  		printk_safe_enter_irqsave(flags);
@@ -373,7 +600,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  skip:
  		if (!prb_read_valid(prb, console_seq, &r))
  			break;
-@@ -2624,7 +2587,6 @@ void console_unlock(void)
+@@ -2469,7 +2526,6 @@ void console_unlock(void)
  				console_msg_format & MSG_FORMAT_SYSLOG,
  				printk_time);
  		console_seq++;
@@ -381,7 +608,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  
  		/*
  		 * While actively printing out messages, if another printk()
-@@ -2651,8 +2613,6 @@ void console_unlock(void)
+@@ -2496,8 +2552,6 @@ void console_unlock(void)
  
  	console_locked = 0;
  
@@ -390,7 +617,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	up_console_sem();
  
  	/*
-@@ -2661,9 +2621,7 @@ void console_unlock(void)
+@@ -2506,9 +2560,7 @@ void console_unlock(void)
  	 * there's a new owner and the console_unlock() from them will do the
  	 * flush, no worries.
  	 */
@@ -400,7 +627,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	printk_safe_exit_irqrestore(flags);
  
  	if (retry && console_trylock())
-@@ -2727,13 +2685,8 @@ void console_flush_on_panic(enum con_flu
+@@ -2572,13 +2624,8 @@ void console_flush_on_panic(enum con_flu
  	console_trylock();
  	console_may_schedule = 0;
  
@@ -415,7 +642,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	console_unlock();
  }
  
-@@ -2957,11 +2910,7 @@ void register_console(struct console *ne
+@@ -2802,11 +2849,7 @@ void register_console(struct console *ne
  		nr_ext_console_drivers++;
  
  	if (newcon->flags & CON_PRINTBUFFER) {
@@ -424,20 +651,20 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 -		 * for us.
 -		 */
 -		logbuf_lock_irqsave(flags);
-+		syslog_lock_irqsave(flags);
++		spin_lock_irqsave(&syslog_lock, flags);
  		/*
  		 * We're about to replay the log buffer.  Only do this to the
  		 * just-registered console to avoid excessive message spam to
-@@ -2974,7 +2923,7 @@ void register_console(struct console *ne
+@@ -2819,7 +2862,7 @@ void register_console(struct console *ne
  		exclusive_console = newcon;
  		exclusive_console_stop_seq = console_seq;
  		console_seq = syslog_seq;
 -		logbuf_unlock_irqrestore(flags);
-+		syslog_unlock_irqrestore(flags);
++		spin_unlock_irqrestore(&syslog_lock, flags);
  	}
  	console_unlock();
  	console_sysfs_notify();
-@@ -3340,7 +3289,6 @@ EXPORT_SYMBOL_GPL(kmsg_dump_reason_str);
+@@ -3185,7 +3228,6 @@ EXPORT_SYMBOL_GPL(kmsg_dump_reason_str);
  void kmsg_dump(enum kmsg_dump_reason reason)
  {
  	struct kmsg_dumper *dumper;
@@ -445,7 +672,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  
  	rcu_read_lock();
  	list_for_each_entry_rcu(dumper, &dump_list, list) {
-@@ -3360,10 +3308,7 @@ void kmsg_dump(enum kmsg_dump_reason rea
+@@ -3205,10 +3247,7 @@ void kmsg_dump(enum kmsg_dump_reason rea
  		/* initialize iterator with data about the stored records */
  		dumper->active = true;
  
@@ -457,7 +684,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  
  		/* invoke dumper which will iterate over records */
  		dumper->dump(dumper, reason);
-@@ -3450,14 +3395,7 @@ bool kmsg_dump_get_line_nolock(struct km
+@@ -3295,14 +3334,7 @@ bool kmsg_dump_get_line_nolock(struct km
  bool kmsg_dump_get_line(struct kmsg_dumper *dumper, bool syslog,
  			char *line, size_t size, size_t *len)
  {
@@ -473,7 +700,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  }
  EXPORT_SYMBOL_GPL(kmsg_dump_get_line);
  
-@@ -3486,7 +3424,6 @@ bool kmsg_dump_get_buffer(struct kmsg_du
+@@ -3331,7 +3363,6 @@ bool kmsg_dump_get_buffer(struct kmsg_du
  	struct printk_info info;
  	unsigned int line_count;
  	struct printk_record r;
@@ -481,7 +708,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	u64 seq;
  	u64 next_seq;
  	size_t len = 0;
-@@ -3496,17 +3433,14 @@ bool kmsg_dump_get_buffer(struct kmsg_du
+@@ -3341,17 +3372,14 @@ bool kmsg_dump_get_buffer(struct kmsg_du
  	if (!dumper->active || !buf || !size)
  		goto out;
  
@@ -500,7 +727,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  
  	/*
  	 * Find first record that fits, including all following records,
-@@ -3549,7 +3483,6 @@ bool kmsg_dump_get_buffer(struct kmsg_du
+@@ -3394,7 +3422,6 @@ bool kmsg_dump_get_buffer(struct kmsg_du
  
  	dumper->next_seq = next_seq;
  	ret = true;
@@ -508,7 +735,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  out:
  	if (len_out)
  		*len_out = len;
-@@ -3564,8 +3497,6 @@ EXPORT_SYMBOL_GPL(kmsg_dump_get_buffer);
+@@ -3409,8 +3436,6 @@ EXPORT_SYMBOL_GPL(kmsg_dump_get_buffer);
   * Reset the dumper's iterator so that kmsg_dump_get_line() and
   * kmsg_dump_get_buffer() can be called again and used multiple
   * times within the same dumper.dump() callback.
@@ -517,7 +744,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
   */
  void kmsg_dump_rewind_nolock(struct kmsg_dumper *dumper)
  {
-@@ -3583,11 +3514,7 @@ void kmsg_dump_rewind_nolock(struct kmsg
+@@ -3428,11 +3453,7 @@ void kmsg_dump_rewind_nolock(struct kmsg
   */
  void kmsg_dump_rewind(struct kmsg_dumper *dumper)
  {
diff --git a/patches/0005-printk-remove-safe-buffers.patch b/patches/0005-printk-remove-safe-buffers.patch
index ba8805748b07..874938b4efeb 100644
--- a/patches/0005-printk-remove-safe-buffers.patch
+++ b/patches/0005-printk-remove-safe-buffers.patch
@@ -1,6 +1,6 @@
 From: John Ogness <john.ogness@linutronix.de>
-Date: Wed, 14 Oct 2020 20:00:11 +0200
-Subject: [PATCH 05/15] printk: remove safe buffers
+Date: Mon, 30 Nov 2020 01:42:00 +0106
+Subject: [PATCH 05/16] printk: remove safe buffers
 
 With @logbuf_lock removed, the high level printk functions for
 storing messages are lockless. Messages can be stored from any
@@ -50,7 +50,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  
 --- a/include/linux/printk.h
 +++ b/include/linux/printk.h
-@@ -207,8 +207,6 @@ void __init setup_log_buf(int early);
+@@ -208,8 +208,6 @@ void __init setup_log_buf(int early);
  void dump_stack_print_info(const char *log_lvl);
  void show_regs_print_info(const char *log_lvl);
  extern asmlinkage void dump_stack(void) __cold;
@@ -59,7 +59,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  #else
  static inline __printf(1, 0)
  int vprintk(const char *s, va_list args)
-@@ -272,14 +270,6 @@ static inline void show_regs_print_info(
+@@ -273,14 +271,6 @@ static inline void show_regs_print_info(
  static inline void dump_stack(void)
  {
  }
@@ -122,7 +122,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  #endif /* CONFIG_PRINTK */
 --- a/kernel/printk/printk.c
 +++ b/kernel/printk/printk.c
-@@ -1037,9 +1037,6 @@ static inline void log_buf_add_cpu(void)
+@@ -987,9 +987,6 @@ static inline void log_buf_add_cpu(void)
  
  static void __init set_percpu_data_ready(void)
  {
diff --git a/patches/0006-console-add-write_atomic-interface.patch b/patches/0006-console-add-write_atomic-interface.patch
index 0c25e4ae99c2..b1d6bdd94f72 100644
--- a/patches/0006-console-add-write_atomic-interface.patch
+++ b/patches/0006-console-add-write_atomic-interface.patch
@@ -1,6 +1,6 @@
 From: John Ogness <john.ogness@linutronix.de>
-Date: Wed, 14 Oct 2020 20:26:35 +0200
-Subject: [PATCH 06/15] console: add write_atomic interface
+Date: Mon, 30 Nov 2020 01:42:01 +0106
+Subject: [PATCH 06/16] console: add write_atomic interface
 
 Add a write_atomic() callback to the console. This is an optional
 function for console drivers. The function must be atomic (including
@@ -34,7 +34,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  struct console {
  	char	name[16];
  	void	(*write)(struct console *, const char *, unsigned);
-+	void	(*write_atomic)(struct console *, const char *, unsigned);
++	void	(*write_atomic)(struct console *co, const char *s, unsigned int count);
  	int	(*read)(struct console *, char *, unsigned);
  	struct tty_driver *(*device)(struct console *, int *);
  	void	(*unblank)(void);
@@ -48,7 +48,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  #endif /* _LINUX_CONSOLE_H */
 --- a/kernel/printk/printk.c
 +++ b/kernel/printk/printk.c
-@@ -3516,3 +3516,103 @@ void kmsg_dump_rewind(struct kmsg_dumper
+@@ -3455,3 +3455,103 @@ void kmsg_dump_rewind(struct kmsg_dumper
  EXPORT_SYMBOL_GPL(kmsg_dump_rewind);
  
  #endif
@@ -105,7 +105,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 + *
 + * It is safe to call this function from any context and state.
 + */
-+void prb_lock(struct prb_cpulock *cpu_lock, unsigned int *cpu_store)
++static void prb_lock(struct prb_cpulock *cpu_lock, unsigned int *cpu_store)
 +{
 +	for (;;) {
 +		if (__prb_trylock(cpu_lock, cpu_store))
@@ -123,7 +123,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 + *
 + * It is safe to call this function from any context and state.
 + */
-+void prb_unlock(struct prb_cpulock *cpu_lock, unsigned int cpu_store)
++static void prb_unlock(struct prb_cpulock *cpu_lock, unsigned int cpu_store)
 +{
 +	unsigned long *flags;
 +	unsigned int cpu;
diff --git a/patches/0007-serial-8250-implement-write_atomic.patch b/patches/0007-serial-8250-implement-write_atomic.patch
index 1b88e78b4d7c..b1aef776d287 100644
--- a/patches/0007-serial-8250-implement-write_atomic.patch
+++ b/patches/0007-serial-8250-implement-write_atomic.patch
@@ -1,6 +1,6 @@
 From: John Ogness <john.ogness@linutronix.de>
-Date: Wed, 14 Oct 2020 20:31:46 +0200
-Subject: [PATCH 07/15] serial: 8250: implement write_atomic
+Date: Mon, 30 Nov 2020 01:42:02 +0106
+Subject: [PATCH 07/16] serial: 8250: implement write_atomic
 
 Implement a non-sleeping NMI-safe write_atomic() console function in
 order to support emergency console printing.
diff --git a/patches/0009-printk-relocate-printk_delay-and-vprintk_default.patch b/patches/0008-printk-relocate-printk_delay-and-vprintk_default.patch
index ffd29dfd11af..89139600b8fd 100644
--- a/patches/0009-printk-relocate-printk_delay-and-vprintk_default.patch
+++ b/patches/0008-printk-relocate-printk_delay-and-vprintk_default.patch
@@ -1,11 +1,11 @@
 From: John Ogness <john.ogness@linutronix.de>
-Date: Mon, 19 Oct 2020 21:02:40 +0206
-Subject: [PATCH 09/15] printk: relocate printk_delay() and vprintk_default()
+Date: Mon, 30 Nov 2020 01:42:03 +0106
+Subject: [PATCH 08/16] printk: relocate printk_delay() and vprintk_default()
 
 Move printk_delay() and vprintk_default() "as is" further up so that
 they can be used by new functions in an upcoming commit.
 
-Signed-off-by: John Ogness <john.ogness@linutornix.de>
+Signed-off-by: John Ogness <john.ogness@linutronix.de>
 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 ---
  kernel/printk/printk.c |   40 ++++++++++++++++++++--------------------
@@ -13,8 +13,8 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 
 --- a/kernel/printk/printk.c
 +++ b/kernel/printk/printk.c
-@@ -1751,6 +1751,20 @@ static void put_sprint_buf(int id, unsig
- 	local_irq_restore(flags);
+@@ -1624,6 +1624,20 @@ SYSCALL_DEFINE3(syslog, int, type, char
+ 	return do_syslog(type, buf, len, SYSLOG_FROM_READER);
  }
  
 +int printk_delay_msec __read_mostly;
@@ -34,8 +34,8 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  /*
   * Special console_lock variants that help to reduce the risk of soft-lockups.
   * They allow to pass console_lock to another printk() call using a busy wait.
-@@ -1935,20 +1949,6 @@ static void call_console_drivers(const c
- 	}
+@@ -1867,20 +1881,6 @@ static void printk_exit(unsigned long fl
+ 	local_irq_restore(flags);
  }
  
 -int printk_delay_msec __read_mostly;
@@ -55,7 +55,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  static inline u32 printk_caller_id(void)
  {
  	return in_task() ? task_pid_nr(current) :
-@@ -2119,18 +2119,18 @@ asmlinkage int vprintk_emit(int facility
+@@ -2073,18 +2073,18 @@ asmlinkage int vprintk_emit(int facility
  }
  EXPORT_SYMBOL(vprintk_emit);
  
diff --git a/patches/0010-printk-combine-boot_delay_msec-into-printk_delay.patch b/patches/0009-printk-combine-boot_delay_msec-into-printk_delay.patch
index 54892f3d062f..ed47f9da8faf 100644
--- a/patches/0010-printk-combine-boot_delay_msec-into-printk_delay.patch
+++ b/patches/0009-printk-combine-boot_delay_msec-into-printk_delay.patch
@@ -1,6 +1,6 @@
 From: John Ogness <john.ogness@linutronix.de>
-Date: Mon, 19 Oct 2020 22:11:31 +0206
-Subject: [PATCH 10/15] printk: combine boot_delay_msec() into printk_delay()
+Date: Mon, 30 Nov 2020 01:42:04 +0106
+Subject: [PATCH 09/16] printk: combine boot_delay_msec() into printk_delay()
 
 boot_delay_msec() is always called immediately before printk_delay()
 so just combine the two.
@@ -13,7 +13,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 
 --- a/kernel/printk/printk.c
 +++ b/kernel/printk/printk.c
-@@ -1753,8 +1753,10 @@ static void put_sprint_buf(int id, unsig
+@@ -1626,8 +1626,10 @@ SYSCALL_DEFINE3(syslog, int, type, char
  
  int printk_delay_msec __read_mostly;
  
@@ -25,7 +25,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	if (unlikely(printk_delay_msec)) {
  		int m = printk_delay_msec;
  
-@@ -2090,8 +2092,7 @@ asmlinkage int vprintk_emit(int facility
+@@ -2044,8 +2046,7 @@ asmlinkage int vprintk_emit(int facility
  		in_sched = true;
  	}
  
diff --git a/patches/0010-printk-change-console_seq-to-atomic64_t.patch b/patches/0010-printk-change-console_seq-to-atomic64_t.patch
new file mode 100644
index 000000000000..5299e29eecca
--- /dev/null
+++ b/patches/0010-printk-change-console_seq-to-atomic64_t.patch
@@ -0,0 +1,122 @@
+From: John Ogness <john.ogness@linutronix.de>
+Date: Mon, 30 Nov 2020 01:42:05 +0106
+Subject: [PATCH 10/16] printk: change @console_seq to atomic64_t
+
+In preparation for atomic printing, change @console_seq to atomic
+so that it can be accessed without requiring @console_sem.
+
+Signed-off-by: John Ogness <john.ogness@linutronix.de>
+Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+---
+ kernel/printk/printk.c |   34 +++++++++++++++++++---------------
+ 1 file changed, 19 insertions(+), 15 deletions(-)
+
+--- a/kernel/printk/printk.c
++++ b/kernel/printk/printk.c
+@@ -366,12 +366,13 @@ static u64 syslog_seq;
+ static size_t syslog_partial;
+ static bool syslog_time;
+ 
+-/* All 3 protected by @console_sem. */
+-/* the next printk record to write to the console */
+-static u64 console_seq;
++/* Both protected by @console_sem. */
+ static u64 exclusive_console_stop_seq;
+ static unsigned long console_dropped;
+ 
++/* the next printk record to write to the console */
++static atomic64_t console_seq = ATOMIC64_INIT(0);
++
+ /* the next printk record to read after the last 'clear' command */
+ static atomic64_t clear_seq = ATOMIC64_INIT(0);
+ 
+@@ -2130,7 +2131,7 @@ EXPORT_SYMBOL(printk);
+ #define prb_first_valid_seq(rb)		0
+ 
+ static u64 syslog_seq;
+-static u64 console_seq;
++static atomic64_t console_seq = ATOMIC64_INIT(0);
+ static u64 exclusive_console_stop_seq;
+ static unsigned long console_dropped;
+ 
+@@ -2439,6 +2440,7 @@ void console_unlock(void)
+ 	bool do_cond_resched, retry;
+ 	struct printk_info info;
+ 	struct printk_record r;
++	u64 seq;
+ 
+ 	if (console_suspended) {
+ 		up_console_sem();
+@@ -2482,12 +2484,14 @@ void console_unlock(void)
+ 
+ 		printk_safe_enter_irqsave(flags);
+ skip:
+-		if (!prb_read_valid(prb, console_seq, &r))
++		seq = atomic64_read(&console_seq);
++		if (!prb_read_valid(prb, seq, &r))
+ 			break;
+ 
+-		if (console_seq != r.info->seq) {
+-			console_dropped += r.info->seq - console_seq;
+-			console_seq = r.info->seq;
++		if (seq != r.info->seq) {
++			console_dropped += r.info->seq - seq;
++			atomic64_set(&console_seq, r.info->seq);
++			seq = r.info->seq;
+ 		}
+ 
+ 		if (suppress_message_printing(r.info->level)) {
+@@ -2496,13 +2500,13 @@ void console_unlock(void)
+ 			 * directly to the console when we received it, and
+ 			 * record that has level above the console loglevel.
+ 			 */
+-			console_seq++;
++			atomic64_set(&console_seq, seq + 1);
+ 			goto skip;
+ 		}
+ 
+ 		/* Output to all consoles once old messages replayed. */
+ 		if (unlikely(exclusive_console &&
+-			     console_seq >= exclusive_console_stop_seq)) {
++			     seq >= exclusive_console_stop_seq)) {
+ 			exclusive_console = NULL;
+ 		}
+ 
+@@ -2523,7 +2527,7 @@ void console_unlock(void)
+ 		len = record_print_text(&r,
+ 				console_msg_format & MSG_FORMAT_SYSLOG,
+ 				printk_time);
+-		console_seq++;
++		atomic64_set(&console_seq, seq + 1);
+ 
+ 		/*
+ 		 * While actively printing out messages, if another printk()
+@@ -2558,7 +2562,7 @@ void console_unlock(void)
+ 	 * there's a new owner and the console_unlock() from them will do the
+ 	 * flush, no worries.
+ 	 */
+-	retry = prb_read_valid(prb, console_seq, NULL);
++	retry = prb_read_valid(prb, atomic64_read(&console_seq), NULL);
+ 	printk_safe_exit_irqrestore(flags);
+ 
+ 	if (retry && console_trylock())
+@@ -2623,7 +2627,7 @@ void console_flush_on_panic(enum con_flu
+ 	console_may_schedule = 0;
+ 
+ 	if (mode == CONSOLE_REPLAY_ALL)
+-		console_seq = prb_first_valid_seq(prb);
++		atomic64_set(&console_seq, prb_first_valid_seq(prb));
+ 	console_unlock();
+ }
+ 
+@@ -2858,8 +2862,8 @@ void register_console(struct console *ne
+ 		 * ignores console_lock.
+ 		 */
+ 		exclusive_console = newcon;
+-		exclusive_console_stop_seq = console_seq;
+-		console_seq = syslog_seq;
++		exclusive_console_stop_seq = atomic64_read(&console_seq);
++		atomic64_set(&console_seq, syslog_seq);
+ 		spin_unlock_irqrestore(&syslog_lock, flags);
+ 	}
+ 	console_unlock();
diff --git a/patches/0011-printk-introduce-kernel-sync-mode.patch b/patches/0011-printk-introduce-kernel-sync-mode.patch
index 8d7107ee3df0..efcc95736dd9 100644
--- a/patches/0011-printk-introduce-kernel-sync-mode.patch
+++ b/patches/0011-printk-introduce-kernel-sync-mode.patch
@@ -1,20 +1,39 @@
 From: John Ogness <john.ogness@linutronix.de>
-Date: Wed, 14 Oct 2020 20:40:05 +0200
-Subject: [PATCH 11/15] printk: introduce kernel sync mode
+Date: Mon, 30 Nov 2020 01:42:06 +0106
+Subject: [PATCH 11/16] printk: introduce kernel sync mode
 
 When the kernel performs an OOPS, enter into "sync mode":
 
 - only atomic consoles (write_atomic() callback) will print
 - printing occurs within vprintk_store() instead of console_unlock()
 
-Change @console_seq to atomic64_t for atomic access.
-
 Signed-off-by: John Ogness <john.ogness@linutronix.de>
 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 ---
- kernel/printk/printk.c |  165 ++++++++++++++++++++++++++++++++++++++++++++-----
- 1 file changed, 150 insertions(+), 15 deletions(-)
+ include/linux/console.h |    4 +
+ kernel/printk/printk.c  |  142 +++++++++++++++++++++++++++++++++++++++++++++++-
+ 2 files changed, 144 insertions(+), 2 deletions(-)
 
+--- a/include/linux/console.h
++++ b/include/linux/console.h
+@@ -16,6 +16,7 @@
+ 
+ #include <linux/atomic.h>
+ #include <linux/types.h>
++#include <linux/printk.h>
+ 
+ struct vc_data;
+ struct console_font_op;
+@@ -151,6 +152,9 @@ struct console {
+ 	short	flags;
+ 	short	index;
+ 	int	cflag;
++#ifdef CONFIG_PRINTK
++	char	sync_buf[CONSOLE_LOG_MAX];
++#endif
+ 	void	*data;
+ 	struct	 console *next;
+ };
 --- a/kernel/printk/printk.c
 +++ b/kernel/printk/printk.c
 @@ -44,6 +44,7 @@
@@ -25,34 +44,17 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  #include <linux/sched/clock.h>
  #include <linux/sched/debug.h>
  #include <linux/sched/task_stack.h>
-@@ -78,6 +79,9 @@ EXPORT_SYMBOL(ignore_console_lock_warnin
- int oops_in_progress;
- EXPORT_SYMBOL(oops_in_progress);
+@@ -359,6 +360,9 @@ enum log_flags {
+ static DEFINE_SPINLOCK(syslog_lock);
  
+ #ifdef CONFIG_PRINTK
 +/* Set to enable sync mode. Once set, it is never cleared. */
 +static bool sync_mode;
 +
- /*
-  * console_sem protects the console_drivers list, and also
-  * provides serialisation for access to the entire console
-@@ -370,12 +374,13 @@ static u64 syslog_seq;
- static size_t syslog_partial;
- static bool syslog_time;
- 
--/* All 3 protected by @console_sem. */
--/* the next printk record to write to the console */
--static u64 console_seq;
-+/* Both protected by @console_sem. */
- static u64 exclusive_console_stop_seq;
- static unsigned long console_dropped;
- 
-+/* the next printk record to write to the console */
-+static atomic64_t console_seq = ATOMIC64_INIT(0);
-+
- /* the next printk record to read after the last 'clear' command */
- static atomic64_t clear_seq = ATOMIC64_INIT(0);
- 
-@@ -1767,6 +1772,110 @@ static inline void printk_delay(int leve
+ DECLARE_WAIT_QUEUE_HEAD(log_wait);
+ /* All 3 protected by @syslog_lock. */
+ /* the next printk record to read by syslog(READ) or /proc/kmsg */
+@@ -1641,6 +1645,110 @@ static inline void printk_delay(int leve
  	}
  }
  
@@ -106,20 +108,20 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 +	return false;
 +}
 +
-+static bool print_sync(struct console *con, char *buf, size_t buf_size, u64 *seq)
++static bool print_sync(struct console *con, u64 *seq)
 +{
 +	struct printk_info info;
 +	struct printk_record r;
 +	size_t text_len;
 +
-+	prb_rec_init_rd(&r, &info, buf, buf_size);
++	prb_rec_init_rd(&r, &info, &con->sync_buf[0], sizeof(con->sync_buf));
 +
 +	if (!prb_read_valid(prb, *seq, &r))
 +		return false;
 +
 +	text_len = record_print_text(&r, console_msg_format & MSG_FORMAT_SYSLOG, printk_time);
 +
-+	if (!call_sync_console_driver(con, buf, text_len))
++	if (!call_sync_console_driver(con, &con->sync_buf[0], text_len))
 +		return false;
 +
 +	*seq = r.info->seq;
@@ -135,7 +137,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 +	return true;
 +}
 +
-+static void print_sync_until(u64 seq, struct console *con, char *buf, size_t buf_size)
++static void print_sync_until(struct console *con, u64 seq)
 +{
 +	unsigned int flags;
 +	u64 printk_seq;
@@ -143,7 +145,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 +	if (!con) {
 +		for_each_console(con) {
 +			if (console_can_sync(con))
-+				print_sync_until(seq, con, buf, buf_size);
++				print_sync_until(con, seq);
 +		}
 +		return;
 +	}
@@ -153,7 +155,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 +		printk_seq = atomic64_read(&console_seq);
 +		if (printk_seq >= seq)
 +			break;
-+		if (!print_sync(con, buf, buf_size, &printk_seq))
++		if (!print_sync(con, &printk_seq))
 +			break;
 +		atomic64_set(&console_seq, printk_seq + 1);
 +	}
@@ -163,7 +165,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  /*
   * Special console_lock variants that help to reduce the risk of soft-lockups.
   * They allow to pass console_lock to another printk() call using a busy wait.
-@@ -1941,6 +2050,8 @@ static void call_console_drivers(const c
+@@ -1815,6 +1923,8 @@ static void call_console_drivers(const c
  		if (!cpu_online(smp_processor_id()) &&
  		    !(con->flags & CON_ANYTIME))
  			continue;
@@ -172,15 +174,31 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  		if (con->flags & CON_EXTENDED)
  			con->write(con, ext_text, ext_len);
  		else {
-@@ -1964,6 +2075,7 @@ int vprintk_store(int facility, int leve
+@@ -1926,6 +2036,7 @@ int vprintk_store(int facility, int leve
  	const u32 caller_id = printk_caller_id();
  	struct prb_reserved_entry e;
  	enum log_flags lflags = 0;
 +	bool final_commit = false;
- 	unsigned long irqflags;
  	struct printk_record r;
+ 	unsigned long irqflags;
  	u16 trunc_msg_len = 0;
-@@ -2027,6 +2139,7 @@ int vprintk_store(int facility, int leve
+@@ -1934,6 +2045,7 @@ int vprintk_store(int facility, int leve
+ 	u16 text_len;
+ 	int ret = 0;
+ 	u64 ts_nsec;
++	u64 seq;
+ 
+ 	ts_nsec = local_clock();
+ 
+@@ -1979,6 +2091,7 @@ int vprintk_store(int facility, int leve
+ 	if (lflags & LOG_CONT) {
+ 		prb_rec_init_wr(&r, text_len);
+ 		if (prb_reserve_in_last(&e, prb, &r, caller_id, LOG_LINE_MAX)) {
++			seq = r.info->seq;
+ 			text_len = printk_sprint(&r.text_buf[r.info->text_len], text_len,
+ 						 facility, &lflags, fmt, args2);
+ 			r.info->text_len += text_len;
+@@ -1986,6 +2099,7 @@ int vprintk_store(int facility, int leve
  			if (lflags & LOG_NEWLINE) {
  				r.info->flags |= LOG_NEWLINE;
  				prb_final_commit(&e);
@@ -188,32 +206,47 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  			} else {
  				prb_commit(&e);
  			}
-@@ -2068,10 +2181,15 @@ int vprintk_store(int facility, int leve
+@@ -2005,6 +2119,8 @@ int vprintk_store(int facility, int leve
+ 			goto out;
+ 	}
+ 
++	seq = r.info->seq;
++
+ 	/* fill message */
+ 	text_len = printk_sprint(&r.text_buf[0], text_len, facility, &lflags, fmt, args2);
+ 	if (trunc_msg_len)
+@@ -2019,13 +2135,19 @@ int vprintk_store(int facility, int leve
+ 		memcpy(&r.info->dev_info, dev_info, sizeof(r.info->dev_info));
+ 
+ 	/* A message without a trailing newline can be continued. */
+-	if (!(lflags & LOG_NEWLINE))
++	if (!(lflags & LOG_NEWLINE)) {
  		prb_commit(&e);
- 	} else {
+-	else
++	} else {
  		prb_final_commit(&e);
 +		final_commit = true;
- 	}
++	}
  
  	ret = text_len + trunc_msg_len;
  out:
 +	/* only the kernel may perform synchronous printing */
 +	if (facility == 0 && final_commit && any_console_can_sync())
-+		print_sync_until(seq + 1, NULL, text, PREFIX_MAX + LOG_LINE_MAX);
++		print_sync_until(NULL, seq + 1);
 +
- 	put_sprint_buf(sprint_id, irqflags);
+ 	va_end(args2);
+ 	printk_exit(irqflags);
  	return ret;
- }
-@@ -2176,7 +2294,7 @@ EXPORT_SYMBOL(printk);
+@@ -2130,6 +2252,8 @@ EXPORT_SYMBOL(printk);
+ #define prb_read_valid(rb, seq, r)	false
  #define prb_first_valid_seq(rb)		0
  
++#define kernel_sync_mode()	false
++
  static u64 syslog_seq;
--static u64 console_seq;
-+static atomic64_t console_seq = ATOMI64_INIT(0);
+ static atomic64_t console_seq = ATOMIC64_INIT(0);
  static u64 exclusive_console_stop_seq;
- static unsigned long console_dropped;
- 
-@@ -2460,6 +2578,8 @@ static int have_callable_console(void)
+@@ -2415,6 +2539,8 @@ static int have_callable_console(void)
   */
  static inline int can_use_console(void)
  {
@@ -222,88 +255,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	return cpu_online(raw_smp_processor_id()) || have_callable_console();
  }
  
-@@ -2485,6 +2605,7 @@ void console_unlock(void)
- 	bool do_cond_resched, retry;
- 	struct printk_info info;
- 	struct printk_record r;
-+	u64 seq;
- 
- 	if (console_suspended) {
- 		up_console_sem();
-@@ -2528,12 +2649,14 @@ void console_unlock(void)
- 
- 		printk_safe_enter_irqsave(flags);
- skip:
--		if (!prb_read_valid(prb, console_seq, &r))
-+		seq = atomic64_read(&console_seq);
-+		if (!prb_read_valid(prb, seq, &r))
- 			break;
- 
--		if (console_seq != r.info->seq) {
--			console_dropped += r.info->seq - console_seq;
--			console_seq = r.info->seq;
-+		if (seq != r.info->seq) {
-+			console_dropped += r.info->seq - seq;
-+			atomic64_set(&console_seq, r.info->seq);
-+			seq = r.info->seq;
- 		}
- 
- 		if (suppress_message_printing(r.info->level)) {
-@@ -2542,13 +2665,13 @@ void console_unlock(void)
- 			 * directly to the console when we received it, and
- 			 * record that has level above the console loglevel.
- 			 */
--			console_seq++;
-+			atomic64_set(&console_seq, seq + 1);
- 			goto skip;
- 		}
- 
- 		/* Output to all consoles once old messages replayed. */
- 		if (unlikely(exclusive_console &&
--			     console_seq >= exclusive_console_stop_seq)) {
-+			     seq >= exclusive_console_stop_seq)) {
- 			exclusive_console = NULL;
- 		}
- 
-@@ -2569,7 +2692,7 @@ void console_unlock(void)
- 		len = record_print_text(&r,
- 				console_msg_format & MSG_FORMAT_SYSLOG,
- 				printk_time);
--		console_seq++;
-+		atomic64_set(&console_seq, seq + 1);
- 
- 		/*
- 		 * While actively printing out messages, if another printk()
-@@ -2604,7 +2727,7 @@ void console_unlock(void)
- 	 * there's a new owner and the console_unlock() from them will do the
- 	 * flush, no worries.
- 	 */
--	retry = prb_read_valid(prb, console_seq, NULL);
-+	retry = prb_read_valid(prb, atomic64_read(&console_seq), NULL);
- 	printk_safe_exit_irqrestore(flags);
- 
- 	if (retry && console_trylock())
-@@ -2669,7 +2792,7 @@ void console_flush_on_panic(enum con_flu
- 	console_may_schedule = 0;
- 
- 	if (mode == CONSOLE_REPLAY_ALL)
--		console_seq = prb_first_valid_seq(prb);
-+		atomic64_set(&console_seq, prb_first_valid_seq(prb));
- 	console_unlock();
- }
- 
-@@ -2904,8 +3027,8 @@ void register_console(struct console *ne
- 		 * ignores console_lock.
- 		 */
- 		exclusive_console = newcon;
--		exclusive_console_stop_seq = console_seq;
--		console_seq = syslog_seq;
-+		exclusive_console_stop_seq = atomic64_read(&console_seq);
-+		atomic64_set(&console_seq, syslog_seq);
- 		syslog_unlock_irqrestore(flags);
- 	}
- 	console_unlock();
-@@ -3273,6 +3396,18 @@ void kmsg_dump(enum kmsg_dump_reason rea
+@@ -3231,6 +3357,18 @@ void kmsg_dump(enum kmsg_dump_reason rea
  {
  	struct kmsg_dumper *dumper;
  
diff --git a/patches/0012-printk-move-console-printing-to-kthreads.patch b/patches/0012-printk-move-console-printing-to-kthreads.patch
index 39df8851ff79..4f3310e13ed0 100644
--- a/patches/0012-printk-move-console-printing-to-kthreads.patch
+++ b/patches/0012-printk-move-console-printing-to-kthreads.patch
@@ -1,6 +1,6 @@
 From: John Ogness <john.ogness@linutronix.de>
-Date: Mon, 19 Oct 2020 22:30:38 +0206
-Subject: [PATCH 12/15] printk: move console printing to kthreads
+Date: Mon, 30 Nov 2020 01:42:07 +0106
+Subject: [PATCH 12/16] printk: move console printing to kthreads
 
 Create a kthread for each console to perform console printing. Now
 all console printing is fully asynchronous except for the boot
@@ -14,15 +14,15 @@ Signed-off-by: John Ogness <john.ogness@linutronix.de>
 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 ---
  include/linux/console.h |    2 
- kernel/printk/printk.c  |  586 +++++++++++++++---------------------------------
- 2 files changed, 190 insertions(+), 398 deletions(-)
+ kernel/printk/printk.c  |  635 ++++++++++++++----------------------------------
+ 2 files changed, 192 insertions(+), 445 deletions(-)
 
 --- a/include/linux/console.h
 +++ b/include/linux/console.h
-@@ -151,6 +151,8 @@ struct console {
- 	short	flags;
- 	short	index;
- 	int	cflag;
+@@ -155,6 +155,8 @@ struct console {
+ #ifdef CONFIG_PRINTK
+ 	char	sync_buf[CONSOLE_LOG_MAX];
+ #endif
 +	atomic64_t printk_seq;
 +	struct task_struct *thread;
  	void	*data;
@@ -38,7 +38,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  #include <linux/clocksource.h>
  #include <linux/sched/clock.h>
  #include <linux/sched/debug.h>
-@@ -271,11 +272,6 @@ static void __up_console_sem(unsigned lo
+@@ -268,11 +269,6 @@ static void __up_console_sem(unsigned lo
  static int console_locked, console_suspended;
  
  /*
@@ -50,7 +50,19 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
   *	Array of consoles built from command line options (console=)
   */
  
-@@ -374,13 +370,6 @@ static u64 syslog_seq;
+@@ -356,10 +352,10 @@ enum log_flags {
+ 	LOG_CONT	= 8,	/* text is a fragment of a continuation line */
+ };
+ 
++#ifdef CONFIG_PRINTK
+ /* The syslog_lock protects syslog_* variables. */
+ static DEFINE_SPINLOCK(syslog_lock);
+ 
+-#ifdef CONFIG_PRINTK
+ /* Set to enable sync mode. Once set, it is never cleared. */
+ static bool sync_mode;
+ 
+@@ -370,13 +366,6 @@ static u64 syslog_seq;
  static size_t syslog_partial;
  static bool syslog_time;
  
@@ -64,7 +76,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  /* the next printk record to read after the last 'clear' command */
  static atomic64_t clear_seq = ATOMIC64_INIT(0);
  
-@@ -1783,6 +1772,8 @@ static bool console_can_sync(struct cons
+@@ -1656,6 +1645,8 @@ static bool console_can_sync(struct cons
  		return false;
  	if (con->write_atomic && kernel_sync_mode())
  		return true;
@@ -73,7 +85,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	return false;
  }
  
-@@ -1792,6 +1783,8 @@ static bool call_sync_console_driver(str
+@@ -1665,6 +1656,8 @@ static bool call_sync_console_driver(str
  		return false;
  	if (con->write_atomic && kernel_sync_mode())
  		con->write_atomic(con, text, text_len);
@@ -82,7 +94,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	else
  		return false;
  
-@@ -1866,202 +1859,16 @@ static void print_sync_until(u64 seq, st
+@@ -1739,202 +1732,16 @@ static void print_sync_until(struct cons
  
  	console_atomic_lock(&flags);
  	for (;;) {
@@ -90,7 +102,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 +		printk_seq = atomic64_read(&con->printk_seq);
  		if (printk_seq >= seq)
  			break;
- 		if (!print_sync(con, buf, buf_size, &printk_seq))
+ 		if (!print_sync(con, &printk_seq))
  			break;
 -		atomic64_set(&console_seq, printk_seq + 1);
 +		atomic64_set(&con->printk_seq, printk_seq + 1);
@@ -284,10 +296,10 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 -	}
 -}
 -
- static inline u32 printk_caller_id(void)
- {
- 	return in_task() ? task_pid_nr(current) :
-@@ -2199,40 +2006,16 @@ asmlinkage int vprintk_emit(int facility
+ #ifdef CONFIG_PRINTK_NMI
+ #define NUM_RECURSION_CTX 2
+ #else
+@@ -2158,40 +1965,16 @@ asmlinkage int vprintk_emit(int facility
  			    const char *fmt, va_list args)
  {
  	int printed_len;
@@ -302,9 +314,9 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  		level = LOGLEVEL_DEFAULT;
 -		in_sched = true;
 -	}
--
--	printk_delay(level);
  
+-	printk_delay(level);
+-
 -	/* This stops the holder of console_sem just where we want him */
  	printed_len = vprintk_store(facility, level, dev_info, fmt, args);
  
@@ -329,35 +341,233 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	wake_up_klogd();
  	return printed_len;
  }
-@@ -2294,9 +2077,6 @@ EXPORT_SYMBOL(printk);
+@@ -2243,6 +2026,153 @@ asmlinkage __visible int printk(const ch
+ }
+ EXPORT_SYMBOL(printk);
+ 
++static int printk_kthread_func(void *data)
++{
++	struct console *con = data;
++	unsigned long dropped = 0;
++	char *dropped_text = NULL;
++	struct printk_info info;
++	struct printk_record r;
++	char *ext_text = NULL;
++	size_t dropped_len;
++	int ret = -ENOMEM;
++	char *text = NULL;
++	char *write_text;
++	u64 printk_seq;
++	size_t len;
++	int error;
++	u64 seq;
++
++	if (con->flags & CON_EXTENDED) {
++		ext_text = kmalloc(CONSOLE_EXT_LOG_MAX, GFP_KERNEL);
++		if (!ext_text)
++			goto out;
++	}
++	text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);
++	dropped_text = kmalloc(64, GFP_KERNEL);
++	if (!text || !dropped_text)
++		goto out;
++
++	if (con->flags & CON_EXTENDED)
++		write_text = ext_text;
++	else
++		write_text = text;
++
++	seq = atomic64_read(&con->printk_seq);
++
++	prb_rec_init_rd(&r, &info, text, LOG_LINE_MAX + PREFIX_MAX);
++
++	for (;;) {
++		error = wait_event_interruptible(log_wait,
++				prb_read_valid(prb, seq, &r) || kthread_should_stop());
++
++		if (kthread_should_stop())
++			break;
++
++		if (error)
++			continue;
++
++		if (seq != r.info->seq) {
++			dropped += r.info->seq - seq;
++			seq = r.info->seq;
++		}
++
++		seq++;
++
++		if (!(con->flags & CON_ENABLED))
++			continue;
++
++		if (suppress_message_printing(r.info->level))
++			continue;
++
++		if (con->flags & CON_EXTENDED) {
++			len = info_print_ext_header(ext_text,
++				CONSOLE_EXT_LOG_MAX,
++				r.info);
++			len += msg_print_ext_body(ext_text + len,
++				CONSOLE_EXT_LOG_MAX - len,
++				&r.text_buf[0], r.info->text_len,
++				&r.info->dev_info);
++		} else {
++			len = record_print_text(&r,
++				console_msg_format & MSG_FORMAT_SYSLOG,
++				printk_time);
++		}
++
++		printk_seq = atomic64_read(&con->printk_seq);
++
++		console_lock();
++		console_may_schedule = 0;
++
++		if (kernel_sync_mode() && con->write_atomic) {
++			console_unlock();
++			break;
++		}
++
++		if (!(con->flags & CON_EXTENDED) && dropped) {
++			dropped_len = snprintf(dropped_text, 64,
++					       "** %lu printk messages dropped **\n",
++					       dropped);
++			dropped = 0;
++
++			con->write(con, dropped_text, dropped_len);
++			printk_delay(r.info->level);
++		}
++
++		con->write(con, write_text, len);
++		if (len)
++			printk_delay(r.info->level);
++
++		atomic64_cmpxchg_relaxed(&con->printk_seq, printk_seq, seq);
++
++		console_unlock();
++	}
++out:
++	kfree(dropped_text);
++	kfree(text);
++	kfree(ext_text);
++	pr_info("%sconsole [%s%d]: printing thread stopped\n",
++		(con->flags & CON_BOOT) ? "boot" : "",
++		con->name, con->index);
++	return ret;
++}
++
++/* Must be called within console_lock(). */
++static void start_printk_kthread(struct console *con)
++{
++	con->thread = kthread_run(printk_kthread_func, con,
++				  "pr/%s%d", con->name, con->index);
++	if (IS_ERR(con->thread)) {
++		pr_err("%sconsole [%s%d]: unable to start printing thread\n",
++			(con->flags & CON_BOOT) ? "boot" : "",
++			con->name, con->index);
++		return;
++	}
++	pr_info("%sconsole [%s%d]: printing thread started\n",
++		(con->flags & CON_BOOT) ? "boot" : "",
++		con->name, con->index);
++}
++
++/* protected by console_lock */
++static bool kthreads_started;
++
++/* Must be called within console_lock(). */
++static void console_try_thread(struct console *con)
++{
++	if (kthreads_started) {
++		start_printk_kthread(con);
++		return;
++	}
++
++	/*
++	 * The printing threads have not been started yet. If this console
++	 * can print synchronously, print all unprinted messages.
++	 */
++
++	if (console_can_sync(con))
++		print_sync_until(con, prb_next_seq(prb));
++}
++
+ #else /* CONFIG_PRINTK */
+ 
+ #define LOG_LINE_MAX		0
+@@ -2251,32 +2181,11 @@ EXPORT_SYMBOL(printk);
+ 
+ #define prb_read_valid(rb, seq, r)	false
  #define prb_first_valid_seq(rb)		0
++#define prb_next_seq(rb)		0
  
- static u64 syslog_seq;
--static atomic64_t console_seq = ATOMI64_INIT(0);
+ #define kernel_sync_mode()	false
+ 
+-static u64 syslog_seq;
+-static atomic64_t console_seq = ATOMIC64_INIT(0);
 -static u64 exclusive_console_stop_seq;
 -static unsigned long console_dropped;
- 
- static size_t record_print_text(const struct printk_record *r,
- 				bool syslog, bool time)
-@@ -2311,8 +2091,6 @@ static ssize_t info_print_ext_header(cha
- static ssize_t msg_print_ext_body(char *buf, size_t size,
- 				  char *text, size_t text_len,
- 				  struct dev_printk_info *dev_info) { return 0; }
+-
+-static size_t record_print_text(const struct printk_record *r,
+-				bool syslog, bool time)
+-{
+-	return 0;
+-}
+-static ssize_t info_print_ext_header(char *buf, size_t size,
+-				     struct printk_info *info)
+-{
+-	return 0;
+-}
+-static ssize_t msg_print_ext_body(char *buf, size_t size,
+-				  char *text, size_t text_len,
+-				  struct dev_printk_info *dev_info) { return 0; }
 -static void console_lock_spinning_enable(void) { }
 -static int console_lock_spinning_disable_and_check(void) { return 0; }
- static void call_console_drivers(const char *ext_text, size_t ext_len,
- 				 const char *text, size_t len) {}
- static bool suppress_message_printing(int level) { return false; }
-@@ -2578,8 +2356,6 @@ static int have_callable_console(void)
-  */
- static inline int can_use_console(void)
- {
--	if (kernel_sync_mode())
--		return false;
- 	return cpu_online(raw_smp_processor_id()) || have_callable_console();
+-static void call_console_drivers(const char *ext_text, size_t ext_len,
+-				 const char *text, size_t len) {}
+-static bool suppress_message_printing(int level) { return false; }
++#define console_try_thread(con)
+ 
+ #endif /* CONFIG_PRINTK */
+ 
+@@ -2514,36 +2423,6 @@ int is_console_locked(void)
  }
+ EXPORT_SYMBOL(is_console_locked);
  
-@@ -2599,139 +2375,14 @@ static inline int can_use_console(void)
+-/*
+- * Check if we have any console that is capable of printing while cpu is
+- * booting or shutting down. Requires console_sem.
+- */
+-static int have_callable_console(void)
+-{
+-	struct console *con;
+-
+-	for_each_console(con)
+-		if ((con->flags & CON_ENABLED) &&
+-				(con->flags & CON_ANYTIME))
+-			return 1;
+-
+-	return 0;
+-}
+-
+-/*
+- * Can we actually use the console at this time on this cpu?
+- *
+- * Console drivers may assume that per-cpu resources have been allocated. So
+- * unless they're explicitly marked as being able to cope (CON_ANYTIME) don't
+- * call them until this CPU is officially up.
+- */
+-static inline int can_use_console(void)
+-{
+-	if (kernel_sync_mode())
+-		return false;
+-	return cpu_online(raw_smp_processor_id()) || have_callable_console();
+-}
+-
+ /**
+  * console_unlock - unlock the console system
+  *
+@@ -2560,139 +2439,14 @@ static inline int can_use_console(void)
   */
  void console_unlock(void)
  {
@@ -497,7 +707,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  }
  EXPORT_SYMBOL(console_unlock);
  
-@@ -2781,18 +2432,20 @@ void console_unblank(void)
+@@ -2742,18 +2496,20 @@ void console_unblank(void)
   */
  void console_flush_on_panic(enum con_flush_mode mode)
  {
@@ -528,16 +738,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	console_unlock();
  }
  
-@@ -2906,6 +2559,8 @@ static int try_enable_new_console(struct
- 	return -ENOENT;
- }
- 
-+static void console_try_thread(struct console *con);
-+
- /*
-  * The console driver calls this routine during kernel initialization
-  * to register the console printing procedure with printk() and to
-@@ -2927,7 +2582,6 @@ static int try_enable_new_console(struct
+@@ -2888,7 +2644,6 @@ static int try_enable_new_console(struct
   */
  void register_console(struct console *newcon)
  {
@@ -545,7 +746,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	struct console *bcon = NULL;
  	int err;
  
-@@ -2951,6 +2605,8 @@ void register_console(struct console *ne
+@@ -2912,6 +2667,8 @@ void register_console(struct console *ne
  		}
  	}
  
@@ -554,12 +755,12 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	if (console_drivers && console_drivers->flags & CON_BOOT)
  		bcon = console_drivers;
  
-@@ -3015,22 +2671,12 @@ void register_console(struct console *ne
+@@ -2976,22 +2733,12 @@ void register_console(struct console *ne
  	if (newcon->flags & CON_EXTENDED)
  		nr_ext_console_drivers++;
  
 -	if (newcon->flags & CON_PRINTBUFFER) {
--		syslog_lock_irqsave(flags);
+-		spin_lock_irqsave(&syslog_lock, flags);
 -		/*
 -		 * We're about to replay the log buffer.  Only do this to the
 -		 * just-registered console to avoid excessive message spam to
@@ -572,7 +773,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 -		exclusive_console = newcon;
 -		exclusive_console_stop_seq = atomic64_read(&console_seq);
 -		atomic64_set(&console_seq, syslog_seq);
--		syslog_unlock_irqrestore(flags);
+-		spin_unlock_irqrestore(&syslog_lock, flags);
 -	}
 +	if (newcon->flags & CON_PRINTBUFFER)
 +		atomic64_set(&newcon->printk_seq, 0);
@@ -583,7 +784,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	console_unlock();
  	console_sysfs_notify();
  
-@@ -3104,6 +2750,9 @@ int unregister_console(struct console *c
+@@ -3065,6 +2812,9 @@ int unregister_console(struct console *c
  	console_unlock();
  	console_sysfs_notify();
  
@@ -593,176 +794,23 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	if (console->exit)
  		res = console->exit(console);
  
-@@ -3147,6 +2796,154 @@ void __init console_init(void)
- 	}
- }
- 
-+static int printk_kthread_func(void *data)
-+{
-+	struct console *con = data;
-+	unsigned long dropped = 0;
-+	struct printk_info info;
-+	struct printk_record r;
-+	char *ext_text = NULL;
-+	size_t dropped_len;
-+	char *dropped_text;
-+	int ret = -ENOMEM;
-+	char *write_text;
-+	u64 printk_seq;
-+	size_t len;
-+	char *text;
-+	int error;
-+	u64 seq;
-+
-+	if (con->flags & CON_EXTENDED) {
-+		ext_text = kmalloc(CONSOLE_EXT_LOG_MAX, GFP_KERNEL);
-+		if (!ext_text)
-+			return ret;
-+	}
-+	text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);
-+	dropped_text = kmalloc(64, GFP_KERNEL);
-+	if (!text || !dropped_text)
-+		goto out;
-+
-+	if (con->flags & CON_EXTENDED)
-+		write_text = ext_text;
-+	else
-+		write_text = text;
-+
-+	seq = atomic64_read(&con->printk_seq);
-+
-+	prb_rec_init_rd(&r, &info, text, LOG_LINE_MAX + PREFIX_MAX);
-+
-+	for (;;) {
-+		error = wait_event_interruptible(log_wait,
-+				prb_read_valid(prb, seq, &r) || kthread_should_stop());
-+
-+		if (kthread_should_stop())
-+			break;
-+
-+		if (error)
-+			continue;
-+
-+		if (seq != r.info->seq) {
-+			dropped += r.info->seq - seq;
-+			seq = r.info->seq;
-+		}
-+
-+		seq++;
-+
-+		if (!(con->flags & CON_ENABLED))
-+			continue;
-+
-+		if (suppress_message_printing(r.info->level))
-+			continue;
-+
-+		if (con->flags & CON_EXTENDED) {
-+			len = info_print_ext_header(ext_text,
-+				CONSOLE_EXT_LOG_MAX,
-+				r.info);
-+			len += msg_print_ext_body(ext_text + len,
-+				CONSOLE_EXT_LOG_MAX - len,
-+				&r.text_buf[0], r.info->text_len,
-+				&r.info->dev_info);
-+		} else {
-+			len = record_print_text(&r,
-+				console_msg_format & MSG_FORMAT_SYSLOG,
-+				printk_time);
-+		}
-+
-+		printk_seq = atomic64_read(&con->printk_seq);
-+
-+		console_lock();
-+		console_may_schedule = 0;
-+
-+		if (kernel_sync_mode() && con->write_atomic) {
-+			console_unlock();
-+			break;
-+		}
-+
-+		if (!(con->flags & CON_EXTENDED) && dropped) {
-+			dropped_len = snprintf(dropped_text, 64,
-+					       "** %lu printk messages dropped **\n",
-+					       dropped);
-+			dropped = 0;
-+
-+			con->write(con, dropped_text, dropped_len);
-+			printk_delay(r.info->level);
-+		}
-+
-+		con->write(con, write_text, len);
-+		if (len)
-+			printk_delay(r.info->level);
-+
-+		atomic64_cmpxchg_relaxed(&con->printk_seq, printk_seq, seq);
-+
-+		console_unlock();
-+	}
-+out:
-+	kfree(dropped_text);
-+	kfree(text);
-+	kfree(ext_text);
-+	pr_info("%sconsole [%s%d]: printing thread stopped\n",
-+		(con->flags & CON_BOOT) ? "boot" : "" ,
-+		con->name, con->index);
-+	return ret;
-+}
-+
-+static void start_printk_kthread(struct console *con)
-+{
-+	con->thread = kthread_run(printk_kthread_func, con,
-+				  "pr/%s%d", con->name, con->index);
-+	if (IS_ERR(con->thread)) {
-+		pr_err("%sconsole [%s%d]: unable to start printing thread\n",
-+			(con->flags & CON_BOOT) ? "boot" : "" ,
-+			con->name, con->index);
-+		return;
-+	}
-+	pr_info("%sconsole [%s%d]: printing thread started\n",
-+		(con->flags & CON_BOOT) ? "boot" : "" ,
-+		con->name, con->index);
-+}
-+
-+static bool kthreads_started;
-+
-+static void console_try_thread(struct console *con)
-+{
-+	unsigned long irqflags;
-+	int sprint_id;
-+	char *buf;
-+
-+	if (kthreads_started) {
-+		start_printk_kthread(con);
-+		return;
-+	}
-+
-+	buf = get_sprint_buf(&sprint_id, &irqflags);
-+	if (!buf)
-+		return;
-+
-+	print_sync_until(prb_next_seq(prb), con, buf, PREFIX_MAX + LOG_LINE_MAX);
-+
-+	put_sprint_buf(sprint_id, irqflags);
-+}
-+
- /*
-  * Some boot consoles access data that is in the init section and which will
-  * be discarded after the initcalls have been run. To make sure that no code
-@@ -3186,6 +2983,13 @@ static int __init printk_late_init(void)
+@@ -3147,6 +2897,15 @@ static int __init printk_late_init(void)
  			unregister_console(con);
  		}
  	}
 +
++#ifdef CONFIG_PRINTK
 +	console_lock();
 +	for_each_console(con)
 +		start_printk_kthread(con);
 +	kthreads_started = true;
 +	console_unlock();
++#endif
 +
  	ret = cpuhp_setup_state_nocalls(CPUHP_PRINTK_DEAD, "printk:dead", NULL,
  					console_cpu_notify);
  	WARN_ON(ret < 0);
-@@ -3201,7 +3005,6 @@ late_initcall(printk_late_init);
+@@ -3162,7 +2921,6 @@ late_initcall(printk_late_init);
   * Delayed printk version, for scheduler-internal messages:
   */
  #define PRINTK_PENDING_WAKEUP	0x01
@@ -770,7 +818,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  
  static DEFINE_PER_CPU(int, printk_pending);
  
-@@ -3209,12 +3012,6 @@ static void wake_up_klogd_work_func(stru
+@@ -3170,12 +2928,6 @@ static void wake_up_klogd_work_func(stru
  {
  	int pending = __this_cpu_xchg(printk_pending, 0);
  
@@ -783,7 +831,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	if (pending & PRINTK_PENDING_WAKEUP)
  		wake_up_interruptible(&log_wait);
  }
-@@ -3239,13 +3036,6 @@ void wake_up_klogd(void)
+@@ -3200,13 +2952,6 @@ void wake_up_klogd(void)
  
  void defer_console_output(void)
  {
diff --git a/patches/0013-printk-remove-deferred-printing.patch b/patches/0013-printk-remove-deferred-printing.patch
index d0e55876f372..ca30c73593dd 100644
--- a/patches/0013-printk-remove-deferred-printing.patch
+++ b/patches/0013-printk-remove-deferred-printing.patch
@@ -1,6 +1,6 @@
 From: John Ogness <john.ogness@linutronix.de>
-Date: Mon, 19 Oct 2020 22:53:30 +0206
-Subject: [PATCH 13/15] printk: remove deferred printing
+Date: Mon, 30 Nov 2020 01:42:08 +0106
+Subject: [PATCH 13/16] printk: remove deferred printing
 
 Since printing occurs either atomically or from the printing
 kthread, there is no need for any deferring or tracking possible
@@ -15,10 +15,10 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  include/linux/printk.h      |   12 ------
  kernel/printk/Makefile      |    1 
  kernel/printk/internal.h    |   70 -----------------------------------
- kernel/printk/printk.c      |   40 ++++++--------------
+ kernel/printk/printk.c      |   57 +++++++++++------------------
  kernel/printk/printk_safe.c |   86 --------------------------------------------
  kernel/trace/trace.c        |    2 -
- 9 files changed, 12 insertions(+), 206 deletions(-)
+ 9 files changed, 22 insertions(+), 213 deletions(-)
  delete mode 100644 kernel/printk/internal.h
  delete mode 100644 kernel/printk/printk_safe.c
 
@@ -66,7 +66,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	} while (0)
 --- a/include/linux/printk.h
 +++ b/include/linux/printk.h
-@@ -149,18 +149,6 @@ static inline __printf(1, 2) __cold
+@@ -150,18 +150,6 @@ static inline __printf(1, 2) __cold
  void early_printk(const char *s, ...) { }
  #endif
  
@@ -168,7 +168,15 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 -#endif /* CONFIG_PRINTK */
 --- a/kernel/printk/printk.c
 +++ b/kernel/printk/printk.c
-@@ -60,7 +60,6 @@
+@@ -45,6 +45,7 @@
+ #include <linux/ctype.h>
+ #include <linux/uio.h>
+ #include <linux/kthread.h>
++#include <linux/kdb.h>
+ #include <linux/clocksource.h>
+ #include <linux/sched/clock.h>
+ #include <linux/sched/debug.h>
+@@ -60,7 +61,6 @@
  #include "printk_ringbuffer.h"
  #include "console_cmdline.h"
  #include "braille.h"
@@ -176,7 +184,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  
  int console_printk[4] = {
  	CONSOLE_LOGLEVEL_DEFAULT,	/* console_loglevel */
-@@ -230,19 +229,7 @@ static int nr_ext_console_drivers;
+@@ -227,19 +227,7 @@ static int nr_ext_console_drivers;
  
  static int __down_trylock_console_sem(unsigned long ip)
  {
@@ -197,7 +205,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  		return 1;
  	mutex_acquire(&console_lock_dep_map, 0, 1, ip);
  	return 0;
-@@ -251,13 +238,9 @@ static int __down_trylock_console_sem(un
+@@ -248,13 +236,9 @@ static int __down_trylock_console_sem(un
  
  static void __up_console_sem(unsigned long ip)
  {
@@ -211,11 +219,42 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  }
  #define up_console_sem() __up_console_sem(_RET_IP_)
  
-@@ -2027,6 +2010,16 @@ int vprintk_default(const char *fmt, va_
+@@ -411,7 +395,7 @@ static struct printk_ringbuffer *prb = &
+  */
+ static bool __printk_percpu_data_ready __read_mostly;
+ 
+-bool printk_percpu_data_ready(void)
++static bool printk_percpu_data_ready(void)
+ {
+ 	return __printk_percpu_data_ready;
+ }
+@@ -1836,9 +1820,9 @@ static u16 printk_sprint(char *text, u16
  }
- EXPORT_SYMBOL_GPL(vprintk_default);
  
-+__printf(1, 0) int vprintk_func(const char *fmt, va_list args)
+ __printf(4, 0)
+-int vprintk_store(int facility, int level,
+-		  const struct dev_printk_info *dev_info,
+-		  const char *fmt, va_list args)
++static int vprintk_store(int facility, int level,
++			 const struct dev_printk_info *dev_info,
++			 const char *fmt, va_list args)
+ {
+ 	const u32 caller_id = printk_caller_id();
+ 	struct prb_reserved_entry e;
+@@ -1980,11 +1964,22 @@ asmlinkage int vprintk_emit(int facility
+ }
+ EXPORT_SYMBOL(vprintk_emit);
+ 
+-int vprintk_default(const char *fmt, va_list args)
++__printf(1, 0)
++static int vprintk_default(const char *fmt, va_list args)
+ {
+ 	return vprintk_emit(0, LOGLEVEL_DEFAULT, NULL, fmt, args);
+ }
+-EXPORT_SYMBOL_GPL(vprintk_default);
++
++__printf(1, 0)
++static int vprintk_func(const char *fmt, va_list args)
 +{
 +#ifdef CONFIG_KGDB_KDB
 +	/* Allow to pass printk() to kdb but avoid a recursion. */
@@ -224,20 +263,21 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 +#endif
 +	return vprintk_default(fmt, args);
 +}
-+
+ 
  asmlinkage int vprintk(const char *fmt, va_list args)
  {
- 	return vprintk_func(fmt, args);
-@@ -3034,18 +3027,9 @@ void wake_up_klogd(void)
+@@ -2950,18 +2945,10 @@ void wake_up_klogd(void)
  	preempt_enable();
  }
  
 -void defer_console_output(void)
--{
++__printf(1, 0)
++static int vprintk_deferred(const char *fmt, va_list args)
+ {
 -}
 -
- int vprintk_deferred(const char *fmt, va_list args)
- {
+-int vprintk_deferred(const char *fmt, va_list args)
+-{
 -	int r;
 -
 -	r = vprintk_emit(0, LOGLEVEL_SCHED, NULL, fmt, args);
diff --git a/patches/0014-printk-add-console-handover.patch b/patches/0014-printk-add-console-handover.patch
index be2dfc39c3e2..20fc3125a4ce 100644
--- a/patches/0014-printk-add-console-handover.patch
+++ b/patches/0014-printk-add-console-handover.patch
@@ -1,6 +1,6 @@
 From: John Ogness <john.ogness@linutronix.de>
-Date: Mon, 19 Oct 2020 23:03:44 +0206
-Subject: [PATCH 14/15] printk: add console handover
+Date: Mon, 30 Nov 2020 01:42:09 +0106
+Subject: [PATCH 14/16] printk: add console handover
 
 If earlyprintk is used, a boot console will print directly to the
 console immediately. The boot console will unregister itself as soon
@@ -25,7 +25,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 
 --- a/include/linux/console.h
 +++ b/include/linux/console.h
-@@ -137,6 +137,7 @@ static inline int con_debug_leave(void)
+@@ -138,6 +138,7 @@ static inline int con_debug_leave(void)
  #define CON_ANYTIME	(16) /* Safe to call when cpu is offline */
  #define CON_BRL		(32) /* Used for a braille device */
  #define CON_EXTENDED	(64) /* Use the extended output format a la /dev/kmsg */
@@ -35,7 +35,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	char	name[16];
 --- a/kernel/printk/printk.c
 +++ b/kernel/printk/printk.c
-@@ -1755,6 +1755,8 @@ static bool console_can_sync(struct cons
+@@ -1629,6 +1629,8 @@ static bool console_can_sync(struct cons
  		return false;
  	if (con->write_atomic && kernel_sync_mode())
  		return true;
@@ -44,7 +44,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	if (con->write && (con->flags & CON_BOOT) && !con->thread)
  		return true;
  	return false;
-@@ -1766,6 +1768,8 @@ static bool call_sync_console_driver(str
+@@ -1640,6 +1642,8 @@ static bool call_sync_console_driver(str
  		return false;
  	if (con->write_atomic && kernel_sync_mode())
  		con->write_atomic(con, text, text_len);
@@ -53,7 +53,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	else if (con->write && (con->flags & CON_BOOT) && !con->thread)
  		con->write(con, text, text_len);
  	else
-@@ -2641,8 +2645,10 @@ void register_console(struct console *ne
+@@ -2705,8 +2709,10 @@ void register_console(struct console *ne
  	 * the real console are the same physical device, it's annoying to
  	 * see the beginning boot messages twice
  	 */
diff --git a/patches/0015-printk-add-pr_flush.patch b/patches/0015-printk-add-pr_flush.patch
new file mode 100644
index 000000000000..26a704450f72
--- /dev/null
+++ b/patches/0015-printk-add-pr_flush.patch
@@ -0,0 +1,103 @@
+From: John Ogness <john.ogness@linutronix.de>
+Date: Mon, 30 Nov 2020 01:42:10 +0106
+Subject: [PATCH 15/16] printk: add pr_flush()
+
+Provide a function to allow waiting for console printers to catch
+up to the latest logged message.
+
+Signed-off-by: John Ogness <john.ogness@linutronix.de>
+Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+---
+ include/linux/printk.h |    2 +
+ kernel/printk/printk.c |   72 +++++++++++++++++++++++++++++++++++++++++++++++++
+ 2 files changed, 74 insertions(+)
+
+--- a/include/linux/printk.h
++++ b/include/linux/printk.h
+@@ -476,6 +476,8 @@ extern int kptr_restrict;
+ 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
+ #endif
+ 
++bool pr_flush(bool may_sleep, int timeout_ms, bool reset_on_progress);
++
+ /*
+  * ratelimited messages with local ratelimit_state,
+  * no local ratelimit_state used in the !PRINTK case
+--- a/kernel/printk/printk.c
++++ b/kernel/printk/printk.c
+@@ -3436,3 +3436,75 @@ void console_atomic_unlock(unsigned int
+ 	prb_unlock(&printk_cpulock, flags);
+ }
+ EXPORT_SYMBOL(console_atomic_unlock);
++
++static void pr_msleep(bool may_sleep, int ms)
++{
++	if (may_sleep) {
++		msleep(ms);
++	} else {
++		while (ms--)
++			udelay(1000);
++	}
++}
++
++/**
++ * pr_flush() - Wait for printing threads to catch up.
++ *
++ * @may_sleep:         Context allows msleep() calls.
++ * @timeout_ms:        The maximum time (in ms) to wait.
++ * @reset_on_progress: Reset the timeout if forward progress is seen.
++ *
++ * A value of 0 for @timeout_ms means no waiting will occur. A value of -1
++ * represents infinite waiting.
++ *
++ * If @reset_on_progress is true, the timeout will be reset whenever any
++ * printer has been seen to make some forward progress.
++ *
++ * Context: Any context if @timeout_ms is 0 or @may_sleep is false. Otherwise
++ * process context.
++ * Return: true if all enabled printers are caught up.
++ */
++bool pr_flush(bool may_sleep, int timeout_ms, bool reset_on_progress)
++{
++	int remaining = timeout_ms;
++	struct console *con;
++	u64 last_diff = 0;
++	u64 printk_seq;
++	u64 diff;
++	u64 seq;
++
++	seq = prb_next_seq(prb);
++
++	for (;;) {
++		diff = 0;
++
++		for_each_console(con) {
++			if (!(con->flags & CON_ENABLED))
++				continue;
++			printk_seq = atomic64_read(&con->printk_seq);
++			if (printk_seq < seq)
++				diff += seq - printk_seq;
++		}
++
++		if (diff != last_diff && reset_on_progress)
++			remaining = timeout_ms;
++
++		if (!diff || remaining == 0)
++			break;
++
++		if (remaining < 0) {
++			pr_msleep(may_sleep, 100);
++		} else if (remaining < 100) {
++			pr_msleep(may_sleep, remaining);
++			remaining = 0;
++		} else {
++			pr_msleep(may_sleep, 100);
++			remaining -= 100;
++		}
++
++		last_diff = diff;
++	}
++
++	return (diff == 0);
++}
++EXPORT_SYMBOL(pr_flush);
diff --git a/patches/0016-printk-kmsg_dump-do_mounts-wait-for-printers.patch b/patches/0016-printk-kmsg_dump-do_mounts-wait-for-printers.patch
new file mode 100644
index 000000000000..1479af403f58
--- /dev/null
+++ b/patches/0016-printk-kmsg_dump-do_mounts-wait-for-printers.patch
@@ -0,0 +1,43 @@
+From: John Ogness <john.ogness@linutronix.de>
+Date: Mon, 30 Nov 2020 01:42:11 +0106
+Subject: [PATCH 16/16] printk: kmsg_dump,do_mounts wait for printers
+
+Use pr_flush() to give console printers a chance to finish if no
+atomic console is available. This should probably be implemented
+inside panic(), giving panic() an additional @may_sleep argument.
+But that would require evaluating every panic() caller. For now
+just call pr_flush() for kmsg_dump and when failing to mount the
+root filesystem, since these are both common error paths.
+
+Signed-off-by: John Ogness <john.ogness@linutronix.de>
+Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+---
+ init/do_mounts.c       |    1 +
+ kernel/printk/printk.c |    6 ++++++
+ 2 files changed, 7 insertions(+)
+
+--- a/init/do_mounts.c
++++ b/init/do_mounts.c
+@@ -457,6 +457,7 @@ void __init mount_block_root(char *name,
+ 		printk("DEBUG_BLOCK_EXT_DEVT is enabled, you need to specify "
+ 		       "explicit textual name for \"root=\" boot option.\n");
+ #endif
++		pr_flush(true, 1000, true);
+ 		panic("VFS: Unable to mount root fs on %s", b);
+ 	}
+ 	if (!(flags & SB_RDONLY)) {
+--- a/kernel/printk/printk.c
++++ b/kernel/printk/printk.c
+@@ -3105,6 +3105,12 @@ void kmsg_dump(enum kmsg_dump_reason rea
+ 			sync_mode = true;
+ 			pr_info("enabled sync mode\n");
+ 		}
++
++		/*
++		 * Give the printing threads time to flush, allowing up to 1
++		 * second of no printing forward progress before giving up.
++		 */
++		pr_flush(false, 100, true);
+ 	}
+ 
+ 	rcu_read_lock();
diff --git a/patches/localversion.patch b/patches/localversion.patch
index 12bd473a33f5..25e5fadbaae8 100644
--- a/patches/localversion.patch
+++ b/patches/localversion.patch
@@ -10,4 +10,4 @@ Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
 --- /dev/null
 +++ b/localversion-rt
 @@ -0,0 +1 @@
-+-rt12
++-rt13
diff --git a/patches/mm-zswap-Use-local-lock-to-protect-per-CPU-data.patch b/patches/mm-zswap-Use-local-lock-to-protect-per-CPU-data.patch
index 7d7180d74b41..0b624ecb1c9d 100644
--- a/patches/mm-zswap-Use-local-lock-to-protect-per-CPU-data.patch
+++ b/patches/mm-zswap-Use-local-lock-to-protect-per-CPU-data.patch
@@ -23,8 +23,8 @@ Cc: linux-mm@kvack.org
 Signed-off-by: Luis Claudio R. Goncalves <lgoncalv@redhat.com>
 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 ---
- mm/zswap.c |   41 ++++++++++++++++++++++++++---------------
- 1 file changed, 26 insertions(+), 15 deletions(-)
+ mm/zswap.c |   43 ++++++++++++++++++++++++++++---------------
+ 1 file changed, 28 insertions(+), 15 deletions(-)
 
 --- a/mm/zswap.c
 +++ b/mm/zswap.c
@@ -36,7 +36,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  #include <linux/types.h>
  #include <linux/atomic.h>
  #include <linux/frontswap.h>
-@@ -387,27 +388,35 @@ static struct zswap_entry *zswap_entry_f
+@@ -387,27 +388,37 @@ static struct zswap_entry *zswap_entry_f
  /*********************************
  * per-cpu code
  **********************************/
@@ -47,7 +47,9 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 +	u8 *dstmem;
 +};
 +
-+static DEFINE_PER_CPU(struct zswap_comp, zswap_comp);
++static DEFINE_PER_CPU(struct zswap_comp, zswap_comp) = {
++	.lock = INIT_LOCAL_LOCK(lock),
++};
  
  static int zswap_dstmem_prepare(unsigned int cpu)
  {
@@ -78,7 +80,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  
  	return 0;
  }
-@@ -919,10 +928,11 @@ static int zswap_writeback_entry(struct
+@@ -919,10 +930,11 @@ static int zswap_writeback_entry(struct
  		dlen = PAGE_SIZE;
  		src = (u8 *)zhdr + sizeof(struct zswap_header);
  		dst = kmap_atomic(page);
@@ -92,7 +94,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  		kunmap_atomic(dst);
  		BUG_ON(ret);
  		BUG_ON(dlen != PAGE_SIZE);
-@@ -1074,12 +1084,12 @@ static int zswap_frontswap_store(unsigne
+@@ -1074,12 +1086,12 @@ static int zswap_frontswap_store(unsigne
  	}
  
  	/* compress */
@@ -108,7 +110,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	if (ret) {
  		ret = -EINVAL;
  		goto put_dstmem;
-@@ -1103,7 +1113,7 @@ static int zswap_frontswap_store(unsigne
+@@ -1103,7 +1115,7 @@ static int zswap_frontswap_store(unsigne
  	memcpy(buf, &zhdr, hlen);
  	memcpy(buf + hlen, dst, dlen);
  	zpool_unmap_handle(entry->pool->zpool, handle);
@@ -117,7 +119,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  
  	/* populate entry */
  	entry->offset = offset;
-@@ -1131,7 +1141,7 @@ static int zswap_frontswap_store(unsigne
+@@ -1131,7 +1143,7 @@ static int zswap_frontswap_store(unsigne
  	return 0;
  
  put_dstmem:
@@ -126,7 +128,7 @@ Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
  	zswap_pool_put(entry->pool);
  freepage:
  	zswap_entry_cache_free(entry);
-@@ -1176,9 +1186,10 @@ static int zswap_frontswap_load(unsigned
+@@ -1176,9 +1188,10 @@ static int zswap_frontswap_load(unsigned
  	if (zpool_evictable(entry->pool->zpool))
  		src += sizeof(struct zswap_header);
  	dst = kmap_atomic(page);
diff --git a/patches/notifier-Make-atomic_notifiers-use-raw_spinlock.patch b/patches/notifier-Make-atomic_notifiers-use-raw_spinlock.patch
new file mode 100644
index 000000000000..3ef97ac3f0d1
--- /dev/null
+++ b/patches/notifier-Make-atomic_notifiers-use-raw_spinlock.patch
@@ -0,0 +1,123 @@
+From: Valentin Schneider <valentin.schneider@arm.com>
+Date: Sun, 22 Nov 2020 20:19:04 +0000
+Subject: [PATCH] notifier: Make atomic_notifiers use raw_spinlock
+
+Booting a recent PREEMPT_RT kernel (v5.10-rc3-rt7-rebase) on my arm64 Juno
+leads to the idle task blocking on an RT sleeping spinlock down some
+notifier path:
+
+  [    1.809101] BUG: scheduling while atomic: swapper/5/0/0x00000002
+  [    1.809116] Modules linked in:
+  [    1.809123] Preemption disabled at:
+  [    1.809125] secondary_start_kernel (arch/arm64/kernel/smp.c:227)
+  [    1.809146] CPU: 5 PID: 0 Comm: swapper/5 Tainted: G        W         5.10.0-rc3-rt7 #168
+  [    1.809153] Hardware name: ARM Juno development board (r0) (DT)
+  [    1.809158] Call trace:
+  [    1.809160] dump_backtrace (arch/arm64/kernel/stacktrace.c:100 (discriminator 1))
+  [    1.809170] show_stack (arch/arm64/kernel/stacktrace.c:198)
+  [    1.809178] dump_stack (lib/dump_stack.c:122)
+  [    1.809188] __schedule_bug (kernel/sched/core.c:4886)
+  [    1.809197] __schedule (./arch/arm64/include/asm/preempt.h:18 kernel/sched/core.c:4913 kernel/sched/core.c:5040)
+  [    1.809204] preempt_schedule_lock (kernel/sched/core.c:5365 (discriminator 1))
+  [    1.809210] rt_spin_lock_slowlock_locked (kernel/locking/rtmutex.c:1072)
+  [    1.809217] rt_spin_lock_slowlock (kernel/locking/rtmutex.c:1110)
+  [    1.809224] rt_spin_lock (./include/linux/rcupdate.h:647 kernel/locking/rtmutex.c:1139)
+  [    1.809231] atomic_notifier_call_chain_robust (kernel/notifier.c:71 kernel/notifier.c:118 kernel/notifier.c:186)
+  [    1.809240] cpu_pm_enter (kernel/cpu_pm.c:39 kernel/cpu_pm.c:93)
+  [    1.809249] psci_enter_idle_state (drivers/cpuidle/cpuidle-psci.c:52 drivers/cpuidle/cpuidle-psci.c:129)
+  [    1.809258] cpuidle_enter_state (drivers/cpuidle/cpuidle.c:238)
+  [    1.809267] cpuidle_enter (drivers/cpuidle/cpuidle.c:353)
+  [    1.809275] do_idle (kernel/sched/idle.c:132 kernel/sched/idle.c:213 kernel/sched/idle.c:273)
+  [    1.809282] cpu_startup_entry (kernel/sched/idle.c:368 (discriminator 1))
+  [    1.809288] secondary_start_kernel (arch/arm64/kernel/smp.c:273)
+
+Two points worth noting:
+
+1) That this is conceptually the same issue as pointed out in:
+   313c8c16ee62 ("PM / CPU: replace raw_notifier with atomic_notifier")
+2) Only the _robust() variant of atomic_notifier callchains suffer from
+   this
+
+AFAICT only the cpu_pm_notifier_chain really needs to be changed, but
+singling it out would mean introducing a new (truly) non-blocking API. At
+the same time, callers that are fine with any blocking within the call
+chain should use blocking notifiers, so patching up all atomic_notifier's
+doesn't seem *too* crazy to me.
+
+Fixes: 70d932985757 ("notifier: Fix broken error handling pattern")
+Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
+Reviewed-by: Daniel Bristot de Oliveira <bristot@redhat.com>
+Link: https://lkml.kernel.org/r/20201122201904.30940-1-valentin.schneider@arm.com
+Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+---
+ include/linux/notifier.h |    6 +++---
+ kernel/notifier.c        |   12 ++++++------
+ 2 files changed, 9 insertions(+), 9 deletions(-)
+
+--- a/include/linux/notifier.h
++++ b/include/linux/notifier.h
+@@ -58,7 +58,7 @@ struct notifier_block {
+ };
+ 
+ struct atomic_notifier_head {
+-	spinlock_t lock;
++	raw_spinlock_t lock;
+ 	struct notifier_block __rcu *head;
+ };
+ 
+@@ -78,7 +78,7 @@ struct srcu_notifier_head {
+ };
+ 
+ #define ATOMIC_INIT_NOTIFIER_HEAD(name) do {	\
+-		spin_lock_init(&(name)->lock);	\
++		raw_spin_lock_init(&(name)->lock);	\
+ 		(name)->head = NULL;		\
+ 	} while (0)
+ #define BLOCKING_INIT_NOTIFIER_HEAD(name) do {	\
+@@ -95,7 +95,7 @@ extern void srcu_init_notifier_head(stru
+ 		cleanup_srcu_struct(&(name)->srcu);
+ 
+ #define ATOMIC_NOTIFIER_INIT(name) {				\
+-		.lock = __SPIN_LOCK_UNLOCKED(name.lock),	\
++		.lock = __RAW_SPIN_LOCK_UNLOCKED(name.lock),	\
+ 		.head = NULL }
+ #define BLOCKING_NOTIFIER_INIT(name) {				\
+ 		.rwsem = __RWSEM_INITIALIZER((name).rwsem),	\
+--- a/kernel/notifier.c
++++ b/kernel/notifier.c
+@@ -142,9 +142,9 @@ int atomic_notifier_chain_register(struc
+ 	unsigned long flags;
+ 	int ret;
+ 
+-	spin_lock_irqsave(&nh->lock, flags);
++	raw_spin_lock_irqsave(&nh->lock, flags);
+ 	ret = notifier_chain_register(&nh->head, n);
+-	spin_unlock_irqrestore(&nh->lock, flags);
++	raw_spin_unlock_irqrestore(&nh->lock, flags);
+ 	return ret;
+ }
+ EXPORT_SYMBOL_GPL(atomic_notifier_chain_register);
+@@ -164,9 +164,9 @@ int atomic_notifier_chain_unregister(str
+ 	unsigned long flags;
+ 	int ret;
+ 
+-	spin_lock_irqsave(&nh->lock, flags);
++	raw_spin_lock_irqsave(&nh->lock, flags);
+ 	ret = notifier_chain_unregister(&nh->head, n);
+-	spin_unlock_irqrestore(&nh->lock, flags);
++	raw_spin_unlock_irqrestore(&nh->lock, flags);
+ 	synchronize_rcu();
+ 	return ret;
+ }
+@@ -182,9 +182,9 @@ int atomic_notifier_call_chain_robust(st
+ 	 * Musn't use RCU; because then the notifier list can
+ 	 * change between the up and down traversal.
+ 	 */
+-	spin_lock_irqsave(&nh->lock, flags);
++	raw_spin_lock_irqsave(&nh->lock, flags);
+ 	ret = notifier_call_chain_robust(&nh->head, val_up, val_down, v);
+-	spin_unlock_irqrestore(&nh->lock, flags);
++	raw_spin_unlock_irqrestore(&nh->lock, flags);
+ 
+ 	return ret;
+ }
diff --git a/patches/printk-Tiny-cleanup.patch b/patches/printk-Tiny-cleanup.patch
deleted file mode 100644
index 7408f2a7f869..000000000000
--- a/patches/printk-Tiny-cleanup.patch
+++ /dev/null
@@ -1,145 +0,0 @@
-From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
-Date: Tue, 20 Oct 2020 18:48:16 +0200
-Subject: [PATCH] printk: Tiny cleanup
-
-- mark functions and variables static which are used only in this file.
-- add printf annotation where appropriate
-- remove static functions without caller
-- add kdb header file for kgdb builds.
-
-Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
----
- kernel/printk/printk.c |   62 +++++++++++++++----------------------------------
- 1 file changed, 19 insertions(+), 43 deletions(-)
-
---- a/kernel/printk/printk.c
-+++ b/kernel/printk/printk.c
-@@ -49,6 +49,7 @@
- #include <linux/sched/clock.h>
- #include <linux/sched/debug.h>
- #include <linux/sched/task_stack.h>
-+#include <linux/kdb.h>
- 
- #include <linux/uaccess.h>
- #include <asm/sections.h>
-@@ -339,11 +340,11 @@ enum log_flags {
- };
- 
- /* The syslog_lock protects syslog_* variables. */
--DEFINE_RAW_SPINLOCK(syslog_lock);
--#define syslog_lock_irq() raw_spin_lock_irq(&syslog_lock)
--#define syslog_unlock_irq() raw_spin_unlock_irq(&syslog_lock)
--#define syslog_lock_irqsave(flags) raw_spin_lock_irqsave(&syslog_lock, flags)
--#define syslog_unlock_irqrestore(flags) raw_spin_unlock_irqrestore(&syslog_lock, flags)
-+static DEFINE_SPINLOCK(syslog_lock);
-+#define syslog_lock_irq() spin_lock_irq(&syslog_lock)
-+#define syslog_unlock_irq() spin_unlock_irq(&syslog_lock)
-+#define syslog_lock_irqsave(flags) spin_lock_irqsave(&syslog_lock, flags)
-+#define syslog_unlock_irqrestore(flags) spin_unlock_irqrestore(&syslog_lock, flags)
- 
- #ifdef CONFIG_PRINTK
- DECLARE_WAIT_QUEUE_HEAD(log_wait);
-@@ -398,7 +399,7 @@ static struct printk_ringbuffer *prb = &
-  */
- static bool __printk_percpu_data_ready __read_mostly;
- 
--bool printk_percpu_data_ready(void)
-+static bool printk_percpu_data_ready(void)
- {
- 	return __printk_percpu_data_ready;
- }
-@@ -1862,9 +1863,10 @@ static inline u32 printk_caller_id(void)
- 		0x80000000 + raw_smp_processor_id();
- }
- 
--int vprintk_store(int facility, int level,
--		  const struct dev_printk_info *dev_info,
--		  const char *fmt, va_list args)
-+__printf(4, 0)
-+static int vprintk_store(int facility, int level,
-+			 const struct dev_printk_info *dev_info,
-+			 const char *fmt, va_list args)
- {
- 	const u32 caller_id = printk_caller_id();
- 	struct prb_reserved_entry e;
-@@ -2008,13 +2010,14 @@ asmlinkage int vprintk_emit(int facility
- }
- EXPORT_SYMBOL(vprintk_emit);
- 
--int vprintk_default(const char *fmt, va_list args)
-+ __printf(1, 0)
-+static int vprintk_default(const char *fmt, va_list args)
- {
- 	return vprintk_emit(0, LOGLEVEL_DEFAULT, NULL, fmt, args);
- }
--EXPORT_SYMBOL_GPL(vprintk_default);
- 
--__printf(1, 0) int vprintk_func(const char *fmt, va_list args)
-+__printf(1, 0)
-+static int vprintk_func(const char *fmt, va_list args)
- {
- #ifdef CONFIG_KGDB_KDB
- 	/* Allow to pass printk() to kdb but avoid a recursion. */
-@@ -2328,34 +2331,6 @@ int is_console_locked(void)
- }
- EXPORT_SYMBOL(is_console_locked);
- 
--/*
-- * Check if we have any console that is capable of printing while cpu is
-- * booting or shutting down. Requires console_sem.
-- */
--static int have_callable_console(void)
--{
--	struct console *con;
--
--	for_each_console(con)
--		if ((con->flags & CON_ENABLED) &&
--				(con->flags & CON_ANYTIME))
--			return 1;
--
--	return 0;
--}
--
--/*
-- * Can we actually use the console at this time on this cpu?
-- *
-- * Console drivers may assume that per-cpu resources have been allocated. So
-- * unless they're explicitly marked as being able to cope (CON_ANYTIME) don't
-- * call them until this CPU is officially up.
-- */
--static inline int can_use_console(void)
--{
--	return cpu_online(raw_smp_processor_id()) || have_callable_console();
--}
--
- /**
-  * console_unlock - unlock the console system
-  *
-@@ -3033,7 +3008,8 @@ void wake_up_klogd(void)
- 	preempt_enable();
- }
- 
--int vprintk_deferred(const char *fmt, va_list args)
-+__printf(1, 0)
-+static int vprintk_deferred(const char *fmt, va_list args)
- {
- 	return vprintk_emit(0, LOGLEVEL_DEFAULT, NULL, fmt, args);
- }
-@@ -3470,7 +3446,7 @@ static bool __prb_trylock(struct prb_cpu
-  *
-  * It is safe to call this function from any context and state.
-  */
--void prb_lock(struct prb_cpulock *cpu_lock, unsigned int *cpu_store)
-+static void prb_lock(struct prb_cpulock *cpu_lock, unsigned int *cpu_store)
- {
- 	for (;;) {
- 		if (__prb_trylock(cpu_lock, cpu_store))
-@@ -3488,7 +3464,7 @@ void prb_lock(struct prb_cpulock *cpu_lo
-  *
-  * It is safe to call this function from any context and state.
-  */
--void prb_unlock(struct prb_cpulock *cpu_lock, unsigned int cpu_store)
-+static void prb_unlock(struct prb_cpulock *cpu_lock, unsigned int cpu_store)
- {
- 	unsigned long *flags;
- 	unsigned int cpu;
diff --git a/patches/series b/patches/series
index e65af8c36ba9..b2b8ba0b94bb 100644
--- a/patches/series
+++ b/patches/series
@@ -106,26 +106,30 @@ timers-Don-t-block-on-expiry_lock-for-TIMER_IRQSAFE.patch
 0001-kthread-Move-prio-affinite-change-into-the-newly-cre.patch
 0002-genirq-Move-prio-assignment-into-the-newly-created-t.patch
 
+# 20201122201904.30940-1-valentin.schneider@arm.com
+notifier-Make-atomic_notifiers-use-raw_spinlock.patch
+
 ############################################################
 # Ready for posting
 ############################################################
 
 # John's printk series.
 0001-printk-refactor-kmsg_dump_get_buffer.patch
-0002-printk-use-buffer-pools-for-sprint-buffers.patch
+0002-printk-inline-log_output-log_store-in-vprintk_store.patch
 0003-printk-change-clear_seq-to-atomic64_t.patch
 0004-printk-remove-logbuf_lock-add-syslog_lock.patch
 0005-printk-remove-safe-buffers.patch
 0006-console-add-write_atomic-interface.patch
 0007-serial-8250-implement-write_atomic.patch
-0008-printk-inline-log_output-log_store-in-vprintk_store.patch
-0009-printk-relocate-printk_delay-and-vprintk_default.patch
-0010-printk-combine-boot_delay_msec-into-printk_delay.patch
+0008-printk-relocate-printk_delay-and-vprintk_default.patch
+0009-printk-combine-boot_delay_msec-into-printk_delay.patch
+0010-printk-change-console_seq-to-atomic64_t.patch
 0011-printk-introduce-kernel-sync-mode.patch
 0012-printk-move-console-printing-to-kthreads.patch
 0013-printk-remove-deferred-printing.patch
 0014-printk-add-console-handover.patch
-printk-Tiny-cleanup.patch
+0015-printk-add-pr_flush.patch
+0016-printk-kmsg_dump-do_mounts-wait-for-printers.patch
 
 ############################################################
 # Needs to address review feedback
diff --git a/patches/x86-kvm-require-const-tsc-for-rt.patch b/patches/x86-kvm-require-const-tsc-for-rt.patch
index 0f7b158d2a09..c7cd925d4339 100644
--- a/patches/x86-kvm-require-const-tsc-for-rt.patch
+++ b/patches/x86-kvm-require-const-tsc-for-rt.patch
@@ -14,7 +14,7 @@ Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
 
 --- a/arch/x86/kvm/x86.c
 +++ b/arch/x86/kvm/x86.c
-@@ -7870,6 +7870,14 @@ int kvm_arch_init(void *opaque)
+@@ -7872,6 +7872,14 @@ int kvm_arch_init(void *opaque)
  		goto out;
  	}