From: Chia-Ming Chang Date: Thu, 2 Apr 2026 06:14:06 +0000 (+0800) Subject: md/raid5: fix soft lockup in retry_aligned_read() X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=7f9f7c697474268d9ef9479df3ddfe7cdcfbbffc;p=thirdparty%2Flinux.git md/raid5: fix soft lockup in retry_aligned_read() When retry_aligned_read() encounters an overlapped stripe, it releases the stripe via raid5_release_stripe() which puts it on the lockless released_stripes llist. In the next raid5d loop iteration, release_stripe_list() drains the stripe onto handle_list (since STRIPE_HANDLE is set by the original IO), but retry_aligned_read() runs before handle_active_stripes() and removes the stripe from handle_list via find_get_stripe() -> list_del_init(). This prevents handle_stripe() from ever processing the stripe to resolve the overlap, causing an infinite loop and soft lockup. Fix this by using __release_stripe() with temp_inactive_list instead of raid5_release_stripe() in the failure path, so the stripe does not go through the released_stripes llist. This allows raid5d to break out of its loop, and the overlap will be resolved when the stripe is eventually processed by handle_stripe(). Fixes: 773ca82fa1ee ("raid5: make release_stripe lockless") Cc: stable@vger.kernel.org Signed-off-by: FengWei Shih Signed-off-by: Chia-Ming Chang Link: https://lore.kernel.org/linux-raid/20260402061406.455755-1-chiamingc@synology.com/ Signed-off-by: Yu Kuai --- diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 1f8360d4cdb77..6e79829c5acb6 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -6641,7 +6641,13 @@ static int retry_aligned_read(struct r5conf *conf, struct bio *raid_bio, } if (!add_stripe_bio(sh, raid_bio, dd_idx, 0, 0)) { - raid5_release_stripe(sh); + int hash; + + spin_lock_irq(&conf->device_lock); + hash = sh->hash_lock_index; + __release_stripe(conf, sh, + &conf->temp_inactive_list[hash]); + spin_unlock_irq(&conf->device_lock); conf->retry_read_aligned = raid_bio; conf->retry_read_offset = scnt; return handled;