diff options
Diffstat (limited to 'patches/0028-s390-Prevent-hotplug-rwsem-recursion.patch')
| -rw-r--r-- | patches/0028-s390-Prevent-hotplug-rwsem-recursion.patch | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/patches/0028-s390-Prevent-hotplug-rwsem-recursion.patch b/patches/0028-s390-Prevent-hotplug-rwsem-recursion.patch new file mode 100644 index 000000000000..ec94de3bbaec --- /dev/null +++ b/patches/0028-s390-Prevent-hotplug-rwsem-recursion.patch @@ -0,0 +1,65 @@ +From 5d5dbc4ef27e72104dea6102e4d1a1bf5a8ed971 Mon Sep 17 00:00:00 2001 +From: Thomas Gleixner <tglx@linutronix.de> +Date: Wed, 24 May 2017 10:15:39 +0200 +Subject: [PATCH 28/32] s390: Prevent hotplug rwsem recursion + +The text patching functions which are invoked from jump_label and kprobes +code are protected against cpu hotplug at the call sites. + +Use stop_machine_cpuslocked() to avoid recursion on the cpu hotplug +rwsem. stop_machine_cpuslocked() contains a lockdep assertion to catch any +unprotected callers. + +Signed-off-by: Thomas Gleixner <tglx@linutronix.de> +Acked-by: Ingo Molnar <mingo@kernel.org> +Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> +Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> +Cc: linux-s390@vger.kernel.org +Cc: Peter Zijlstra <peterz@infradead.org> +Cc: Sebastian Siewior <bigeasy@linutronix.de> +Cc: Steven Rostedt <rostedt@goodmis.org> +Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> +Link: http://lkml.kernel.org/r/20170524081549.354513406@linutronix.de +--- + arch/s390/kernel/jump_label.c | 2 +- + arch/s390/kernel/kprobes.c | 4 ++-- + 2 files changed, 3 insertions(+), 3 deletions(-) + +diff --git a/arch/s390/kernel/jump_label.c b/arch/s390/kernel/jump_label.c +index 6aa630a8d24f..262506cee4c3 100644 +--- a/arch/s390/kernel/jump_label.c ++++ b/arch/s390/kernel/jump_label.c +@@ -93,7 +93,7 @@ void arch_jump_label_transform(struct jump_entry *entry, + args.entry = entry; + args.type = type; + +- stop_machine(__sm_arch_jump_label_transform, &args, NULL); ++ stop_machine_cpuslocked(__sm_arch_jump_label_transform, &args, NULL); + } + + void arch_jump_label_transform_static(struct jump_entry *entry, +diff --git a/arch/s390/kernel/kprobes.c b/arch/s390/kernel/kprobes.c +index 3d6a99746454..6842e4501e2e 100644 +--- a/arch/s390/kernel/kprobes.c ++++ b/arch/s390/kernel/kprobes.c +@@ -196,7 +196,7 @@ void arch_arm_kprobe(struct kprobe *p) + { + struct swap_insn_args args = {.p = p, .arm_kprobe = 1}; + +- stop_machine(swap_instruction, &args, NULL); ++ stop_machine_cpuslocked(swap_instruction, &args, NULL); + } + NOKPROBE_SYMBOL(arch_arm_kprobe); + +@@ -204,7 +204,7 @@ void arch_disarm_kprobe(struct kprobe *p) + { + struct swap_insn_args args = {.p = p, .arm_kprobe = 0}; + +- stop_machine(swap_instruction, &args, NULL); ++ stop_machine_cpuslocked(swap_instruction, &args, NULL); + } + NOKPROBE_SYMBOL(arch_disarm_kprobe); + +-- +2.11.0 + |