lkml.org 
[lkml]   [2011]   [Aug]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] x86, perf: check that current->mm alive before getting user callchain
From
Date
On Tue, 2011-08-30 at 12:32 +0400, Andrey Vagin wrote:
> An event may occurs when mm is already released.

> Signed-off-by: Andrey Vagin <avagin@openvz.org>
> ---
> arch/x86/kernel/cpu/perf_event.c | 3 +++
> 1 files changed, 3 insertions(+), 0 deletions(-)
>
> diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
> index 4ee3abf..cfa62ec 100644
> --- a/arch/x86/kernel/cpu/perf_event.c
> +++ b/arch/x86/kernel/cpu/perf_event.c
> @@ -1900,6 +1900,9 @@ perf_callchain_user(struct perf_callchain_entry *entry, struct pt_regs *regs)
>
> perf_callchain_store(entry, regs->ip);
>
> + if (!current->mm)
> + return;
> +
> if (perf_callchain_user32(regs, entry))
> return;
>

Thanks!


\
 
 \ /
  Last update: 2011-08-30 15:17    [W:0.112 / U:0.024 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site