[ANNOUNCE] v5.12-rc3-rt3v5.12-rc3-rt3-patches

Dear RT folks!

I'm pleased to announce the v5.12-rc3-rt3 patch set.

Changes since v5.12-rc3-rt2:

  - Update the softirq/tasklet patches to the latest version which has
    been merged into the tip tree. Only the comments have changed.

  - In certain conditions the SLAB_TYPESAFE_BY_RCU marked SLAB pages may
    have been returned to the page-allocator without waiting for
    required grace period. The problem has been introduced during the
    rework in v5.11.2-rt9.

  - Update John's printk patches.
    With this update I can strike
     - kdb/kgdb can easily deadlock.

    off the known issues list.

Known issues
     - netconsole triggers WARN.

The delta patch against v5.12-rc3-rt2 is appended below and can be found here:

     https://cdn.kernel.org/pub/linux/kernel/projects/rt/5.12/incr/patch-5.12-rc3-rt2-rt3.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 v5.12-rc3-rt3

The RT patch against v5.12-rc3 can be found here:

    https://cdn.kernel.org/pub/linux/kernel/projects/rt/5.12/older/patch-5.12-rc3-rt3.patch.xz

The split quilt queue is available at:

    https://cdn.kernel.org/pub/linux/kernel/projects/rt/5.12/older/patches-5.12-rc3-rt3.tar.xz

Sebastian

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

1 files changed, 84 insertions, 0 deletions

diff --git a/patches/0007-printk-introduce-CONSOLE_LOG_MAX.patch b/patches/0007-printk-introduce-CONSOLE_LOG_MAX.patch
new file mode 100644
index 000000000000..3fdf4b247277
--- /dev/null
+++ b/patches/0007-printk-introduce-CONSOLE_LOG_MAX.patch
@@ -0,0 +1,84 @@
+From: John Ogness <john.ogness@linutronix.de>
+Date: Wed, 3 Mar 2021 11:15:20 +0100
+Subject: [PATCH 07/29] printk: introduce CONSOLE_LOG_MAX
+
+Instead of using "LOG_LINE_MAX + PREFIX_MAX" for temporary buffer
+sizes, introduce CONSOLE_LOG_MAX. This represents the maximum size
+that is allowed to be printed to the console for a single record.
+
+Signed-off-by: John Ogness <john.ogness@linutronix.de>
+Reviewed-by: Petr Mladek <pmladek@suse.com>
+Signed-off-by: Petr Mladek <pmladek@suse.com>
+Link: https://lore.kernel.org/r/20210303101528.29901-8-john.ogness@linutronix.de
+Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+---
+ kernel/printk/printk.c |   20 ++++++++++++--------
+ 1 file changed, 12 insertions(+), 8 deletions(-)
+
+--- a/kernel/printk/printk.c
++++ b/kernel/printk/printk.c
+@@ -410,7 +410,12 @@ static u64 clear_seq;
+ #else
+ #define PREFIX_MAX		32
+ #endif
+-#define LOG_LINE_MAX		(1024 - PREFIX_MAX)
++
++/* the maximum size of a formatted record (i.e. with prefix added per line) */
++#define CONSOLE_LOG_MAX		1024
++
++/* the maximum size allowed to be reserved for a record */
++#define LOG_LINE_MAX		(CONSOLE_LOG_MAX - PREFIX_MAX)
+ 
+ #define LOG_LEVEL(v)		((v) & 0x07)
+ #define LOG_FACILITY(v)		((v) >> 3 & 0xff)
+@@ -1472,11 +1477,11 @@ static int syslog_print(char __user *buf
+ 	char *text;
+ 	int len = 0;
+ 
+-	text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);
++	text = kmalloc(CONSOLE_LOG_MAX, GFP_KERNEL);
+ 	if (!text)
+ 		return -ENOMEM;
+ 
+-	prb_rec_init_rd(&r, &info, text, LOG_LINE_MAX + PREFIX_MAX);
++	prb_rec_init_rd(&r, &info, text, CONSOLE_LOG_MAX);
+ 
+ 	while (size > 0) {
+ 		size_t n;
+@@ -1542,7 +1547,7 @@ static int syslog_print_all(char __user
+ 	u64 seq;
+ 	bool time;
+ 
+-	text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);
++	text = kmalloc(CONSOLE_LOG_MAX, GFP_KERNEL);
+ 	if (!text)
+ 		return -ENOMEM;
+ 
+@@ -1554,7 +1559,7 @@ static int syslog_print_all(char __user
+ 	 */
+ 	seq = find_first_fitting_seq(clear_seq, -1, size, true, time);
+ 
+-	prb_rec_init_rd(&r, &info, text, LOG_LINE_MAX + PREFIX_MAX);
++	prb_rec_init_rd(&r, &info, text, CONSOLE_LOG_MAX);
+ 
+ 	len = 0;
+ 	prb_for_each_record(seq, prb, seq, &r) {
+@@ -2187,8 +2192,7 @@ EXPORT_SYMBOL(printk);
+ 
+ #else /* CONFIG_PRINTK */
+ 
+-#define LOG_LINE_MAX		0
+-#define PREFIX_MAX		0
++#define CONSOLE_LOG_MAX		0
+ #define printk_time		false
+ 
+ #define prb_read_valid(rb, seq, r)	false
+@@ -2506,7 +2510,7 @@ static inline int can_use_console(void)
+ void console_unlock(void)
+ {
+ 	static char ext_text[CONSOLE_EXT_LOG_MAX];
+-	static char text[LOG_LINE_MAX + PREFIX_MAX];
++	static char text[CONSOLE_LOG_MAX];
+ 	unsigned long flags;
+ 	bool do_cond_resched, retry;
+ 	struct printk_info info;