Commit-ID: 0f46efeb44e360b78f54a968b4d92e6877c35891 Gitweb: http://git.kernel.org/tip/0f46efeb44e360b78f54a968b4d92e6877c35891 Author: Masami Hiramatsu <[email protected]> AuthorDate: Thu, 17 Apr 2014 17:17:12 +0900 Committer: Ingo Molnar <[email protected]> CommitDate: Thu, 24 Apr 2014 10:02:57 +0200
kprobes, x86: Prohibit probing on debug_stack_*() Prohibit probing on debug_stack_reset and debug_stack_set_zero. Since the both functions are called from TRACE_IRQS_ON/OFF_DEBUG macros which run in int3 ist entry, probing it may cause a soft lockup. This happens when the kernel built with CONFIG_DYNAMIC_FTRACE=y and CONFIG_TRACE_IRQFLAGS=y. Signed-off-by: Masami Hiramatsu <[email protected]> Reviewed-by: Steven Rostedt <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Jan Beulich <[email protected]> Cc: Paul Gortmaker <[email protected]> Cc: Seiji Aguchi <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/kernel/cpu/common.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index a135239..5af696d 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -8,6 +8,7 @@ #include <linux/delay.h> #include <linux/sched.h> #include <linux/init.h> +#include <linux/kprobes.h> #include <linux/kgdb.h> #include <linux/smp.h> #include <linux/io.h> @@ -1160,6 +1161,7 @@ int is_debug_stack(unsigned long addr) (addr <= __get_cpu_var(debug_stack_addr) && addr > (__get_cpu_var(debug_stack_addr) - DEBUG_STKSZ)); } +NOKPROBE_SYMBOL(is_debug_stack); DEFINE_PER_CPU(u32, debug_idt_ctr); @@ -1168,6 +1170,7 @@ void debug_stack_set_zero(void) this_cpu_inc(debug_idt_ctr); load_current_idt(); } +NOKPROBE_SYMBOL(debug_stack_set_zero); void debug_stack_reset(void) { @@ -1176,6 +1179,7 @@ void debug_stack_reset(void) if (this_cpu_dec_return(debug_idt_ctr) == 0) load_current_idt(); } +NOKPROBE_SYMBOL(debug_stack_reset); #else /* CONFIG_X86_64 */ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
