xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

x86/nmi: Protect NMI entry against instrumentation

Browse Source 
Mark all functions in the fragile code parts noinstr or force inlining so
they can't be instrumented.

Also make the hardware latency tracer invocation explicit outside of
non-instrumentable section.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505135314.716186134@linutronix.de
This commit is contained in:
Thomas Gleixner
2020-04-06 15:55:06 +02:00
parent 6271fef00b
commit f051f69795
3 changed files with 15 additions and 14 deletions
Download Patch File Download Diff File Expand all files Collapse all files

6
arch/x86/kernel/cpu/common.c
View File

@@ -1709,21 +1709,19 @@ void syscall_init(void)
DEFINE_PER_CPU(int, debug_stack_usage);
DEFINE_PER_CPU(u32, debug_idt_ctr);
void debug_stack_set_zero(void)
noinstr 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)
noinstr void debug_stack_reset(void)
{
if (WARN_ON(!this_cpu_read(debug_idt_ctr)))
return;
if (this_cpu_dec_return(debug_idt_ctr) == 0)
load_current_idt();
}
NOKPROBE_SYMBOL(debug_stack_reset);
#else /* CONFIG_X86_64 */