From: Yufen Yu Date: Thu, 20 Aug 2020 13:22:05 +0000 (-0400) Subject: md/raid5: make sure stripe_size as power of two X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=6af10a33c501b0b5878476501143c2cfbbfd63a2;p=linux.git md/raid5: make sure stripe_size as power of two Commit 3b5408b98e4d ("md/raid5: support config stripe_size by sysfs entry") make stripe_size as a configurable value. It just requires stripe_size as multiple of 4KB. In fact, we should make sure stripe_size as power of two. Otherwise, stripe_shift which is the result of ilog2 can not represent the real stripe_size. Then, stripe_hash() and stripe_hash_locks_hash() may get unexpected value. Fixes: 3b5408b98e4d ("md/raid5: support config stripe_size by sysfs entry") Signed-off-by: Yufen Yu Signed-off-by: Song Liu --- diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index ef0fd4830803f..a095c7a4cd7cb 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -6514,9 +6514,12 @@ raid5_store_stripe_size(struct mddev *mddev, const char *page, size_t len) /* * The value should not be bigger than PAGE_SIZE. It requires to - * be multiple of DEFAULT_STRIPE_SIZE. + * be multiple of DEFAULT_STRIPE_SIZE and the value should be power + * of two. */ - if (new % DEFAULT_STRIPE_SIZE != 0 || new > PAGE_SIZE || new == 0) + if (new % DEFAULT_STRIPE_SIZE != 0 || + new > PAGE_SIZE || new == 0 || + new != roundup_pow_of_two(new)) return -EINVAL; err = mddev_lock(mddev);