From: Mikulas Patocka <mpatocka@redhat.com> mainline inclusion from mainline-v6.8-rc2 commit 9f3fe29d77ef4e7f7cb5c4c8c59f6dc373e57e78 category: bugfix bugzilla: https://atomgit.com/openeuler/kernel/issues/8374 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- RCU protection was removed in the commit 2d32777d60de ("raid1: remove rcu protection to access rdev from conf"). However, the code in fix_read_error does rcu_dereference outside rcu_read_lock - this triggers the following warning. The warning is triggered by a LVM2 test shell/integrity-caching.sh. This commit removes rcu_dereference. ============================= WARNING: suspicious RCU usage 6.7.0 #2 Not tainted ----------------------------- drivers/md/raid1.c:2265 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 no locks held by mdX_raid1/1859. stack backtrace: CPU: 2 PID: 1859 Comm: mdX_raid1 Not tainted 6.7.0 #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x60/0x70 lockdep_rcu_suspicious+0x153/0x1b0 raid1d+0x1732/0x1750 [raid1] ? lock_acquire+0x9f/0x270 ? finish_wait+0x3d/0x80 ? md_thread+0xf7/0x130 [md_mod] ? lock_release+0xaa/0x230 ? md_register_thread+0xd0/0xd0 [md_mod] md_thread+0xa0/0x130 [md_mod] ? housekeeping_test_cpu+0x30/0x30 kthread+0xdc/0x110 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x28/0x40 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork_asm+0x11/0x20 </TASK> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Fixes: ca294b34aaf3 ("md/raid1: support read error check") Reviewed-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/51539879-e1ca-fde3-b8b4-8934ddedcbc@redhat.com Signed-off-by: Li Nan <linan122@huawei.com> --- drivers/md/raid1.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 119ef331473d..8820ad4ae0a7 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -2247,7 +2247,7 @@ static void fix_read_error(struct r1conf *conf, struct r1bio *r1_bio) int sectors = r1_bio->sectors; int read_disk = r1_bio->read_disk; struct mddev *mddev = conf->mddev; - struct md_rdev *rdev = rcu_dereference(conf->mirrors[read_disk].rdev); + struct md_rdev *rdev = conf->mirrors[read_disk].rdev; if (exceed_read_errors(mddev, rdev)) { r1_bio->bios[r1_bio->read_disk] = IO_BLOCKED; -- 2.39.2