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author | zijun_hu <zijun_hu@htc.com> | 2016-12-12 16:45:02 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-12-12 18:55:09 -0800 |
commit | 8f6066049c54ef0f726869c27d610cef5d15e084 (patch) | |
tree | f51e74b3a7158fdffa0c9f37f82fffe8fe3d537b /Documentation/cpu-freq | |
parent | c5caf21ab0cf884ef15b25af234f620e4a233139 (diff) |
mm/percpu.c: fix panic triggered by BUG_ON() falsely
As shown by pcpu_build_alloc_info(), the number of units within a percpu
group is deduced by rounding up the number of CPUs within the group to
@upa boundary/ Therefore, the number of CPUs isn't equal to the units's
if it isn't aligned to @upa normally. However, pcpu_page_first_chunk()
uses BUG_ON() to assert that one number is equal to the other roughly,
so a panic is maybe triggered by the BUG_ON() incorrectly.
In order to fix this issue, the number of CPUs is rounded up then
compared with units's and the BUG_ON() is replaced with a warning and
return of an error code as well, to keep system alive as much as
possible.
Link: http://lkml.kernel.org/r/57FCF07C.2020103@zoho.com
Signed-off-by: zijun_hu <zijun_hu@htc.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'Documentation/cpu-freq')
0 files changed, 0 insertions, 0 deletions