From b73eba2a867e10b9b4477738677341f3307c07bb Mon Sep 17 00:00:00 2001 From: Gang He Date: Sat, 4 Jan 2020 13:00:22 -0800 Subject: [PATCH] ocfs2: fix the crash due to call ocfs2_get_dlm_debug once less Because ocfs2_get_dlm_debug() function is called once less here, ocfs2 file system will trigger the system crash, usually after ocfs2 file system is unmounted. This system crash is caused by a generic memory corruption, these crash backtraces are not always the same, for exapmle, ocfs2: Unmounting device (253,16) on (node 172167785) general protection fault: 0000 [#1] SMP PTI CPU: 3 PID: 14107 Comm: fence_legacy Kdump: Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) RIP: 0010:__kmalloc+0xa5/0x2a0 Code: 00 00 4d 8b 07 65 4d 8b RSP: 0018:ffffaa1fc094bbe8 EFLAGS: 00010286 RAX: 0000000000000000 RBX: d310a8800d7a3faf RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000dc0 RDI: ffff96e68fc036c0 RBP: d310a8800d7a3faf R08: ffff96e6ffdb10a0 R09: 00000000752e7079 R10: 000000000001c513 R11: 0000000004091041 R12: 0000000000000dc0 R13: 0000000000000039 R14: ffff96e68fc036c0 R15: ffff96e68fc036c0 FS: 00007f699dfba540(0000) GS:ffff96e6ffd80000(0000) knlGS:00000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055f3a9d9b768 CR3: 000000002cd1c000 CR4: 00000000000006e0 Call Trace: ext4_htree_store_dirent+0x35/0x100 [ext4] htree_dirblock_to_tree+0xea/0x290 [ext4] ext4_htree_fill_tree+0x1c1/0x2d0 [ext4] ext4_readdir+0x67c/0x9d0 [ext4] iterate_dir+0x8d/0x1a0 __x64_sys_getdents+0xab/0x130 do_syscall_64+0x60/0x1f0 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f699d33a9fb This regression problem was introduced by commit e581595ea29c ("ocfs: no need to check return value of debugfs_create functions"). Link: http://lkml.kernel.org/r/20191225061501.13587-1-ghe@suse.com Fixes: e581595ea29c ("ocfs: no need to check return value of debugfs_create functions") Signed-off-by: Gang He Acked-by: Joseph Qi Cc: Mark Fasheh Cc: Joel Becker Cc: Junxiao Bi Cc: Changwei Ge Cc: Gang He Cc: Jun Piao Cc: [5.3+] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/ocfs2/dlmglue.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c index 1c4c51f3df60..cda1027d0819 100644 --- a/fs/ocfs2/dlmglue.c +++ b/fs/ocfs2/dlmglue.c @@ -3282,6 +3282,7 @@ static void ocfs2_dlm_init_debug(struct ocfs2_super *osb) debugfs_create_u32("locking_filter", 0600, osb->osb_debug_root, &dlm_debug->d_filter_secs); + ocfs2_get_dlm_debug(dlm_debug); } static void ocfs2_dlm_shutdown_debug(struct ocfs2_super *osb)