user/sven/linux.git/drivers/md, branch v6.9.5

md/raid5: fix deadlock that raid5d() wait for itself to clear MD_SB_CHANGE_PENDING

2024-06-16T11:50:57Z

commit 151f66bb618d1fd0eeb84acb61b4a9fa5d8bb0fa upstream. Xiao reported that lvm2 test lvconvert-raid-takeover.sh can hang with small possibility, the root cause is exactly the same as commit bed9e27baf52 ("Revert "md/raid5: Wait for MD_SB_CHANGE_PENDING in raid5d"") However, Dan reported another hang after that, and junxiao investigated the problem and found out that this is caused by plugged bio can't issue from raid5d(). Current implementation in raid5d() has a weird dependence: 1) md_check_recovery() from raid5d() must hold 'reconfig_mutex' to clear MD_SB_CHANGE_PENDING; 2) raid5d() handles IO in a deadloop, until all IO are issued; 3) IO from raid5d() must wait for MD_SB_CHANGE_PENDING to be cleared; This behaviour is introduce before v2.6, and for consequence, if other context hold 'reconfig_mutex', and md_check_recovery() can't update super_block, then raid5d() will waste one cpu 100% by the deadloop, until 'reconfig_mutex' is released. Refer to the implementation from raid1 and raid10, fix this problem by skipping issue IO if MD_SB_CHANGE_PENDING is still set after md_check_recovery(), daemon thread will be woken up when 'reconfig_mutex' is released. Meanwhile, the hang problem will be fixed as well. Fixes: 5e2cf333b7bd ("md/raid5: Wait for MD_SB_CHANGE_PENDING in raid5d") Cc: stable@vger.kernel.org # v5.19+ Reported-and-tested-by: Dan Moulding Closes: https://lore.kernel.org/all/20240123005700.9302-1-dan@danm.net/ Investigated-by: Junxiao Bi Signed-off-by: Yu Kuai Link: https://lore.kernel.org/r/20240322081005.1112401-1-yukuai1@huaweicloud.com Signed-off-by: Song Liu Signed-off-by: Greg Kroah-Hartman

bcache: fix variable length array abuse in btree_iter

2024-06-16T11:50:55Z

commit 3a861560ccb35f2a4f0a4b8207fa7c2a35fc7f31 upstream. btree_iter is used in two ways: either allocated on the stack with a fixed size MAX_BSETS, or from a mempool with a dynamic size based on the specific cache set. Previously, the struct had a fixed-length array of size MAX_BSETS which was indexed out-of-bounds for the dynamically-sized iterators, which causes UBSAN to complain. This patch uses the same approach as in bcachefs's sort_iter and splits the iterator into a btree_iter with a flexible array member and a btree_iter_stack which embeds a btree_iter as well as a fixed-length data array. Cc: stable@vger.kernel.org Closes: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2039368 Signed-off-by: Matthew Mirvish Signed-off-by: Coly Li Link: https://lore.kernel.org/r/20240509011117.2697-3-colyli@suse.de Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

dm-delay: fix max_delay calculations

2024-05-30T07:44:35Z

[ Upstream commit 64eb88d6caee2c8eb806a68dab3f184f14f818a4 ] delay_ctr() pointlessly compared max_delay in cases where multiple delay classes were initialized identically. Also, when write delays were configured different than read delays, delay_ctr() never compared their value against max_delay. Fix these issues. Fixes: 70bbeb29fab0 ("dm delay: for short delays, use kthread instead of timers and wq") Signed-off-by: Benjamin Marzinski Signed-off-by: Mike Snitzer Signed-off-by: Sasha Levin

dm-delay: fix hung task introduced by kthread mode

2024-05-30T07:44:35Z

[ Upstream commit d14646f23300a5fc85be867bafdc0702c2002789 ] If the worker thread is not woken due to a bio, then it is not woken at all. This causes the hung task check to trigger. This occurs, for instance, when no bios are submitted. Also when a delay of 0 is configured, delay_bio() returns without waking the worker. Prevent the hung task check from triggering by creating the thread with kthread_run() instead of using kthread_create() directly. Fixes: 70bbeb29fab0 ("dm delay: for short delays, use kthread instead of timers and wq") Signed-off-by: Joel Colledge Reviewed-by: Benjamin Marzinski Signed-off-by: Mike Snitzer Signed-off-by: Sasha Levin

dm-delay: fix workqueue delay_timer race

2024-05-30T07:44:35Z

[ Upstream commit 8d24790ed08ab4e619ce58ed4a1b353ab77ffdc5 ] delay_timer could be pending when delay_dtr() is called. It needs to be shut down before kdelayd_wq is destroyed, so it won't try queueing more work to kdelayd_wq while that's getting destroyed. Also the del_timer_sync() call in delay_presuspend() doesn't protect against the timer getting immediately rearmed by the queued call to flush_delayed_bios(), but there's no real harm if that does happen. timer_delete() is less work, and is basically just as likely to stop a pointless call to flush_delayed_bios(). Fixes: 26b9f228703f ("dm: delay target") Signed-off-by: Benjamin Marzinski Signed-off-by: Mike Snitzer Signed-off-by: Sasha Levin

md: fix resync softlockup when bitmap size is less than array size

2024-05-30T07:44:10Z

[ Upstream commit f0e729af2eb6bee9eb58c4df1087f14ebaefe26b ] Is is reported that for dm-raid10, lvextend + lvchange --syncaction will trigger following softlockup: kernel:watchdog: BUG: soft lockup - CPU#3 stuck for 26s! [mdX_resync:6976] CPU: 7 PID: 3588 Comm: mdX_resync Kdump: loaded Not tainted 6.9.0-rc4-next-20240419 #1 RIP: 0010:_raw_spin_unlock_irq+0x13/0x30 Call Trace: md_bitmap_start_sync+0x6b/0xf0 raid10_sync_request+0x25c/0x1b40 [raid10] md_do_sync+0x64b/0x1020 md_thread+0xa7/0x170 kthread+0xcf/0x100 ret_from_fork+0x30/0x50 ret_from_fork_asm+0x1a/0x30 And the detailed process is as follows: md_do_sync j = mddev->resync_min while (j < max_sectors) sectors = raid10_sync_request(mddev, j, &skipped) if (!md_bitmap_start_sync(..., &sync_blocks)) // md_bitmap_start_sync set sync_blocks to 0 return sync_blocks + sectors_skippe; // sectors = 0; j += sectors; // j never change Root cause is that commit 301867b1c168 ("md/raid10: check slab-out-of-bounds in md_bitmap_get_counter") return early from md_bitmap_get_counter(), without setting returned blocks. Fix this problem by always set returned blocks from md_bitmap_get_counter"(), as it used to be. Noted that this patch just fix the softlockup problem in kernel, the case that bitmap size doesn't match array size still need to be fixed. Fixes: 301867b1c168 ("md/raid10: check slab-out-of-bounds in md_bitmap_get_counter") Reported-and-tested-by: Nigel Croxon Closes: https://lore.kernel.org/all/71ba5272-ab07-43ba-8232-d2da642acb4e@redhat.com/ Signed-off-by: Yu Kuai Link: https://lore.kernel.org/r/20240422065824.2516-1-yukuai1@huaweicloud.com Signed-off-by: Song Liu Signed-off-by: Sasha Levin

Merge tag 'for-6.9/dm-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

2024-04-26T18:17:24Z

Pull device mapper fixes from Mike Snitzer: - Fix 6.9 regression so that DM device removal is performed synchronously by default. Asynchronous removal has always been possible but it isn't the default. It is important that synchronous removal be preserved, otherwise it is an interface change that breaks lvm2. - Remove errant semicolon in drivers/md/dm-vdo/murmurhash3.c * tag 'for-6.9/dm-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: dm: restore synchronous close of device mapper block device dm vdo murmurhash: remove unneeded semicolon

dm: restore synchronous close of device mapper block device

2024-04-16T15:32:07Z

'dmsetup remove' and 'dmsetup remove_all' require synchronous bdev release. Otherwise dm_lock_for_deletion() may return -EBUSY if the open count is > 0, because the open count is dropped in dm_blk_close() which occurs after fput() completes. So if dm_blk_close() is delayed because of asynchronous fput(), this device mapper device is skipped during remove, which is a regression. Fix the issue by using __fput_sync(). Also, DM device removal has long supported being made asynchronous by setting the DMF_DEFERRED_REMOVE flag on the DM device. So leverage using async fput() in close_table_device() if DMF_DEFERRED_REMOVE flag is set. Reported-by: Zhong Changhui Fixes: a28d893eb327 ("md: port block device access to file") Suggested-by: Christian Brauner Signed-off-by: Ming Lei [snitzer: editted commit header, use fput() if DMF_DEFERRED_REMOVE set] Signed-off-by: Mike Snitzer

dm vdo murmurhash: remove unneeded semicolon

2024-04-10T15:46:40Z

Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202404050327.4ebVLBD3-lkp@intel.com/ Signed-off-by: Matthew Sakai Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer

Merge tag 'md-6.9-20240408' of https://git.kernel.org/pub/scm/linux/kernel/git/song/md into block-6.9

2024-04-09T03:49:27Z

Pull MD fix from Song: "This change, by Yu Kuai, fixes a UAF in a corner case." * tag 'md-6.9-20240408' of https://git.kernel.org/pub/scm/linux/kernel/git/song/md: raid1: fix use-after-free for original bio in raid1_write_request()