Messages in this thread Patch in this message | | | Date | Thu, 28 Sep 2017 03:52:58 -0700 | From | tip-bot for Masami Hiramatsu <> | Subject | [tip:perf/core] kprobes/x86: Move the get_kprobe_ctlblk() into irq-disabled block |
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Commit-ID: cd52edad55fbcd8064877a77d31445b2fb4b85c3 Gitweb: https://git.kernel.org/tip/cd52edad55fbcd8064877a77d31445b2fb4b85c3 Author: Masami Hiramatsu <mhiramat@kernel.org> AuthorDate: Tue, 19 Sep 2017 18:59:39 +0900 Committer: Ingo Molnar <mingo@kernel.org> CommitDate: Thu, 28 Sep 2017 09:23:03 +0200
kprobes/x86: Move the get_kprobe_ctlblk() into irq-disabled block
Since get_kprobe_ctlblk() accesses per-cpu variables which calls smp_processor_id(), it must be called under preempt-disabled or irq-disabled.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Alexei Starovoitov <ast@fb.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/150581517952.32348.2655896843219158446.stgit@devbox Signed-off-by: Ingo Molnar <mingo@kernel.org> --- arch/x86/kernel/kprobes/opt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c index 0cae7c0..f558103 100644 --- a/arch/x86/kernel/kprobes/opt.c +++ b/arch/x86/kernel/kprobes/opt.c @@ -154,7 +154,6 @@ STACK_FRAME_NON_STANDARD(optprobe_template_func); static void optimized_callback(struct optimized_kprobe *op, struct pt_regs *regs) { - struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); unsigned long flags; /* This is possible if op is under delayed unoptimizing */ @@ -165,6 +164,7 @@ optimized_callback(struct optimized_kprobe *op, struct pt_regs *regs) if (kprobe_running()) { kprobes_inc_nmissed_count(&op->kp); } else { + struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); /* Save skipped registers */ #ifdef CONFIG_X86_64 regs->cs = __KERNEL_CS;
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