[lkml]   [2015]   [Apr]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH 1/4] perf tools: unwind: ensure unwind hooks return negative errorno.
On 2015/4/1 20:12, Jiri Olsa wrote:
> On Wed, Apr 01, 2015 at 10:33:12AM +0000, Wang Nan wrote:
>> According to man pages of libunwind, unwind hooks should return
>> 'negative value of one of the unw_error_t error-codes', they are
>> different from generic error code. In addition, access_dso_mem()
>> returns '!(size == sizeof(*data))', compiler never ensure it is
>> negative when failure, which causes libunwind get undesire value
>> when accessing //anon memory.
>> This patch fixes this problem by force returning negative value when
>> error, instead of returning 'ret' itself when it is non-zero.
> hum, how about find_proc_info callback.. should it follow the same rules?

Yes, but it only returns -EINVAL and dwarf_search_unwind_table(....). The latter
one is part of libunwind so we can trust it returns negative when fail.

> thanks,
> jirka

 \ /
  Last update: 2015-04-01 15:01    [W:0.106 / U:0.028 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site