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| author | Matthew Wilcox (Oracle) <willy@infradead.org> | 2024-04-29 15:47:51 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-05-02 16:29:32 +0200 |
| commit | 9b7c5004d7c5ae062134052a85290869a015814c (patch) | |
| tree | 0a1959896ef8499ff93cc2c0dd4a75b007129c02 /kernel | |
| parent | 4e75e222d397c6752b229ed72fc4644c8c36ecde (diff) | |
| download | linux-9b7c5004d7c5ae062134052a85290869a015814c.tar.gz linux-9b7c5004d7c5ae062134052a85290869a015814c.tar.bz2 linux-9b7c5004d7c5ae062134052a85290869a015814c.zip | |
bounds: Use the right number of bits for power-of-two CONFIG_NR_CPUS
commit 5af385f5f4cddf908f663974847a4083b2ff2c79 upstream.
bits_per() rounds up to the next power of two when passed a power of
two. This causes crashes on some machines and configurations.
Reported-by: Михаил Новоселов <m.novosyolov@rosalinux.ru>
Tested-by: Ильфат Гаптрахманов <i.gaptrakhmanov@rosalinux.ru>
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/3347
Link: https://lore.kernel.org/all/1c978cf1-2934-4e66-e4b3-e81b04cb3571@rosalinux.ru/
Fixes: f2d5dcb48f7b (bounds: support non-power-of-two CONFIG_NR_CPUS)
Cc: <stable@vger.kernel.org>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bounds.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/bounds.c b/kernel/bounds.c index c5a9fcd2d622..29b2cd00df2c 100644 --- a/kernel/bounds.c +++ b/kernel/bounds.c @@ -19,7 +19,7 @@ int main(void) DEFINE(NR_PAGEFLAGS, __NR_PAGEFLAGS); DEFINE(MAX_NR_ZONES, __MAX_NR_ZONES); #ifdef CONFIG_SMP - DEFINE(NR_CPUS_BITS, bits_per(CONFIG_NR_CPUS)); + DEFINE(NR_CPUS_BITS, order_base_2(CONFIG_NR_CPUS)); #endif DEFINE(SPINLOCK_SIZE, sizeof(spinlock_t)); #ifdef CONFIG_LRU_GEN |