From b0f51883f551b900a04a80f49fb0886caf7e9a12 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Mon, 24 Feb 2020 22:25:03 +0100 Subject: printk: Disallow instrumenting print_nmi_enter() It happens early in nmi_enter(), no tracing, probing or other funnies allowed. Specifically as nmi_enter() will be used in do_debug(), which would cause recursive exceptions when kprobed. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Thomas Gleixner Reviewed-by: Alexandre Chartre Link: https://lkml.kernel.org/r/20200505134101.139720912@linutronix.de --- kernel/printk/printk_safe.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'kernel/printk') diff --git a/kernel/printk/printk_safe.c b/kernel/printk/printk_safe.c index e8791f206417..4242403316bb 100644 --- a/kernel/printk/printk_safe.c +++ b/kernel/printk/printk_safe.c @@ -10,6 +10,7 @@ #include #include #include +#include #include "internal.h" @@ -293,12 +294,12 @@ static __printf(1, 0) int vprintk_nmi(const char *fmt, va_list args) return printk_safe_log_store(s, fmt, args); } -void notrace printk_nmi_enter(void) +void noinstr printk_nmi_enter(void) { this_cpu_add(printk_context, PRINTK_NMI_CONTEXT_OFFSET); } -void notrace printk_nmi_exit(void) +void noinstr printk_nmi_exit(void) { this_cpu_sub(printk_context, PRINTK_NMI_CONTEXT_OFFSET); } -- cgit v1.2.3-59-g8ed1b