6.18-stable review patch. If anyone has any objections, please let me know.
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From: Li Nan linan122@huawei.com
[ Upstream commit 0ce112d9171ad766d4c6716951e73f91a0bfc184 ]
'md_redundancy_group' are created in md_run() and deleted in del_gendisk(), but these are not paired. Writing inactive/active to sysfs array_state can trigger md_run() multiple times without del_gendisk(), leading to duplicate creation as below:
sysfs: cannot create duplicate filename '/devices/virtual/block/md0/md/sync_action' Call Trace: dump_stack_lvl+0x9f/0x120 dump_stack+0x14/0x20 sysfs_warn_dup+0x96/0xc0 sysfs_add_file_mode_ns+0x19c/0x1b0 internal_create_group+0x213/0x830 sysfs_create_group+0x17/0x20 md_run+0x856/0xe60 ? __x64_sys_openat+0x23/0x30 do_md_run+0x26/0x1d0 array_state_store+0x559/0x760 md_attr_store+0xc9/0x1e0 sysfs_kf_write+0x6f/0xa0 kernfs_fop_write_iter+0x141/0x2a0 vfs_write+0x1fc/0x5a0 ksys_write+0x79/0x180 __x64_sys_write+0x1d/0x30 x64_sys_call+0x2818/0x2880 do_syscall_64+0xa9/0x580 entry_SYSCALL_64_after_hwframe+0x4b/0x53 md: cannot register extra attributes for md0
Creation of it depends on 'pers', its lifecycle cannot be aligned with gendisk. So fix this issue by triggering 'md_redundancy_group' deletion when the array is becoming inactive.
Link: https://lore.kernel.org/linux-raid/20251103125757.1405796-2-linan666@huaweic... Fixes: 790abe4d77af ("md: remove/add redundancy group only in level change") Signed-off-by: Li Nan linan122@huawei.com Reviewed-by: Xiao Ni xni@redhat.com Signed-off-by: Yu Kuai yukuai@fnnas.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/md/md.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/drivers/md/md.c b/drivers/md/md.c index 5d40beaecc9c7..7b21eb1dbc533 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -6872,6 +6872,10 @@ static int do_md_stop(struct mddev *mddev, int mode) if (!md_is_rdwr(mddev)) set_disk_ro(disk, 0);
+ if (mode == 2 && mddev->pers->sync_request && + mddev->to_remove == NULL) + mddev->to_remove = &md_redundancy_group; + __md_stop_writes(mddev); __md_stop(mddev);