Messages in this thread | | | Date | Thu, 09 Dec 2010 09:06:37 -0800 | From | Corey Ashford <> | Subject | Re: [PATCH] perf_event: fix error handling path |
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On 12/07/2010 05:51 PM, jovi zhang wrote: > On Mon, Dec 6, 2010 at 9:59 AM, jovi zhang<bookjovi@gmail.com> wrote: >> On Sun, Dec 5, 2010 at 8:29 PM, Thiago Farina<tfransosi@gmail.com> wrote: >>> >>> On Sat, Dec 4, 2010 at 1:19 AM,<bookjovi@gmail.com> wrote: >>>> fix error handling path >>>> >>>> Signed-off-by: Jovi Zhang<bookjovi@gmail.com> >>>> kernel/perf_event.c | 2 -- >>>> 1 files changed, 0 insertions(+), 2 deletions(-) >>>> >>>> diff --git a/kernel/perf_event.c b/kernel/perf_event.c >>>> index cb6c0d2..62f9e9d 100644 >>>> --- a/kernel/perf_event.c >>>> +++ b/kernel/perf_event.c >>>> @@ -1918,8 +1918,6 @@ static int get_callchain_buffers(void) >>>> } >>>> >>>> err = alloc_callchain_buffers(); >>>> - if (err) >>>> - release_callchain_buffers(); >>> >>> Care to explain in the change log message? As I reader, is not clear >>> to me what is wrong with this. >> >> Sorry, the description should be as: >> fix error handling path. alloc_callchain_buffers() can return -ENOMEM, >> in this time callchain_cpus_entries maybe is NULL, It will oops if >> invoke release_callchain_buffers() when callchain_cpus_entries is >> NULL. >> > I hope my understanding is right, is it?
One possible problem here is what if it returns an error other than -ENOMEM, and the buffers do need to be released? Maybe you could change the code to
err = alloc_callchain_buffers(); if (err != -ENOMEM) release_callchain_buffers();
Currently, alloc_callchain_buffers cannot return any error code other than -ENOMEM, but that might change in the future.
- Corey
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