Hi Andrew, On 06/23/2017 05:24 AM, Andrew Morton wrote: > On Thu, 22 Jun 2017 14:10:38 +0800 Joseph Qi <jiangqi...@gmail.com> wrote: > >> Looks good. >> Reviewed-by: Joseph Qi <jiangqi...@gmail.com> > Should this fix be backported into -stable kernels?
No, I think, because the previous patches that this one needs to be on, - commit 439a36b8ef38 ("ocfs2/dlmglue: prepare tracking logic to avoid recursive cluster lock"). - commit b891fa5024a9 ("ocfs2: fix deadlock issue when taking inode lock at vfs entry points") is not in --stable too. I don't know if it's possible to make them all into stable. Thanks, Eric > >> On 17/6/22 09:47, Eric Ren wrote: >>> Another deadlock path caused by recursive locking is reported. >>> This kind of issue was introduced since commit 743b5f1434f5 ("ocfs2: >>> take inode lock in ocfs2_iop_set/get_acl()"). Two deadlock paths >>> have been fixed by commit b891fa5024a9 ("ocfs2: fix deadlock issue when >>> taking inode lock at vfs entry points"). Yes, we intend to fix this >>> kind of case in incremental way, because it's hard to find out all >>> possible paths at once. >>> >>> This one can be reproduced like this. On node1, cp a large file from >>> home directory to ocfs2 mountpoint. While on node2, run setfacl/getfacl. >>> Both nodes will hang up there. The backtraces: >>> >>> On node1: >>> [<ffffffffc06a1f67>] __ocfs2_cluster_lock.isra.39+0x357/0x740 [ocfs2] >>> [<ffffffffc06a2d3d>] ocfs2_inode_lock_full_nested+0x17d/0x840 [ocfs2] >>> [<ffffffffc0692043>] ocfs2_write_begin+0x43/0x1a0 [ocfs2] >>> [<ffffffffa21ac719>] generic_perform_write+0xa9/0x180 >>> [<ffffffffa21aecda>] __generic_file_write_iter+0x1aa/0x1d0 >>> [<ffffffffc06abc24>] ocfs2_file_write_iter+0x4f4/0xb40 [ocfs2] >>> [<ffffffffa223c3b3>] __vfs_write+0xc3/0x130 >>> [<ffffffffa223cae1>] vfs_write+0xb1/0x1a0 >>> [<ffffffffa223dfe6>] SyS_write+0x46/0xa0 >>> >>> On node2: >>> [<ffffffffc07b6f67>] __ocfs2_cluster_lock.isra.39+0x357/0x740 [ocfs2] >>> [<ffffffffc07b7d3d>] ocfs2_inode_lock_full_nested+0x17d/0x840 [ocfs2] >>> [<ffffffffc0815c1e>] ocfs2_xattr_set+0x12e/0xe80 [ocfs2] >>> [<ffffffffc081783d>] ocfs2_set_acl+0x22d/0x260 [ocfs2] >>> [<ffffffffc08178d5>] ocfs2_iop_set_acl+0x65/0xb0 [ocfs2] >>> [<ffffffffa62a43f5>] set_posix_acl+0x75/0xb0 >>> [<ffffffffa62a4479>] posix_acl_xattr_set+0x49/0xa0 >>> [<ffffffffa6265c69>] __vfs_setxattr+0x69/0x80 >>> [<ffffffffa6266832>] __vfs_setxattr_noperm+0x72/0x1a0 >>> [<ffffffffa6266a07>] vfs_setxattr+0xa7/0xb0 >>> [<ffffffffa6266b3d>] setxattr+0x12d/0x190 >>> [<ffffffffa6266c3f>] path_setxattr+0x9f/0xb0 >>> [<ffffffffa6266d74>] SyS_setxattr+0x14/0x20 >>> >>> Fixes this one by using ocfs2_inode_{lock|unlock}_tracker, which is >>> exported by commit 439a36b8ef38 ("ocfs2/dlmglue: prepare tracking >>> logic to avoid recursive cluster lock"). >>> >>> Changes since v1: >>> - Revised git commit description style in commit log. >>> >>> Reported-by: Thomas Voegtle <t...@lio96.de> >>> Tested-by: Thomas Voegtle <t...@lio96.de> >>> Signed-off-by: Eric Ren <z...@suse.com> >>> --- >>> fs/ocfs2/dlmglue.c | 4 ++++ >>> fs/ocfs2/xattr.c | 23 +++++++++++++---------- >>> 2 files changed, 17 insertions(+), 10 deletions(-) >>> >>> diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c >>> index 3b7c937..4689940 100644 >>> --- a/fs/ocfs2/dlmglue.c >>> +++ b/fs/ocfs2/dlmglue.c >>> @@ -2591,6 +2591,10 @@ void ocfs2_inode_unlock_tracker(struct inode *inode, >>> struct ocfs2_lock_res *lockres; >>> >>> lockres = &OCFS2_I(inode)->ip_inode_lockres; >>> + /* had_lock means that the currect process already takes the cluster >>> + * lock previously. If had_lock is 1, we have nothing to do here, and >>> + * it will get unlocked where we got the lock. >>> + */ >>> if (!had_lock) { >>> ocfs2_remove_holder(lockres, oh); >>> ocfs2_inode_unlock(inode, ex); >>> diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c >>> index 3c5384d..f70c377 100644 >>> --- a/fs/ocfs2/xattr.c >>> +++ b/fs/ocfs2/xattr.c >>> @@ -1328,20 +1328,21 @@ static int ocfs2_xattr_get(struct inode *inode, >>> void *buffer, >>> size_t buffer_size) >>> { >>> - int ret; >>> + int ret, had_lock; >>> struct buffer_head *di_bh = NULL; >>> + struct ocfs2_lock_holder oh; >>> >>> - ret = ocfs2_inode_lock(inode, &di_bh, 0); >>> - if (ret < 0) { >>> - mlog_errno(ret); >>> - return ret; >>> + had_lock = ocfs2_inode_lock_tracker(inode, &di_bh, 0, &oh); >>> + if (had_lock < 0) { >>> + mlog_errno(had_lock); >>> + return had_lock; >>> } >>> down_read(&OCFS2_I(inode)->ip_xattr_sem); >>> ret = ocfs2_xattr_get_nolock(inode, di_bh, name_index, >>> name, buffer, buffer_size); >>> up_read(&OCFS2_I(inode)->ip_xattr_sem); >>> >>> - ocfs2_inode_unlock(inode, 0); >>> + ocfs2_inode_unlock_tracker(inode, 0, &oh, had_lock); >>> >>> brelse(di_bh); >>> >>> @@ -3537,11 +3538,12 @@ int ocfs2_xattr_set(struct inode *inode, >>> { >>> struct buffer_head *di_bh = NULL; >>> struct ocfs2_dinode *di; >>> - int ret, credits, ref_meta = 0, ref_credits = 0; >>> + int ret, credits, had_lock, ref_meta = 0, ref_credits = 0; >>> struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); >>> struct inode *tl_inode = osb->osb_tl_inode; >>> struct ocfs2_xattr_set_ctxt ctxt = { NULL, NULL, NULL, }; >>> struct ocfs2_refcount_tree *ref_tree = NULL; >>> + struct ocfs2_lock_holder oh; >>> >>> struct ocfs2_xattr_info xi = { >>> .xi_name_index = name_index, >>> @@ -3572,8 +3574,9 @@ int ocfs2_xattr_set(struct inode *inode, >>> return -ENOMEM; >>> } >>> >>> - ret = ocfs2_inode_lock(inode, &di_bh, 1); >>> - if (ret < 0) { >>> + had_lock = ocfs2_inode_lock_tracker(inode, &di_bh, 1, &oh); >>> + if (had_lock < 0) { >>> + ret = had_lock; >>> mlog_errno(ret); >>> goto cleanup_nolock; >>> } >>> @@ -3670,7 +3673,7 @@ int ocfs2_xattr_set(struct inode *inode, >>> if (ret) >>> mlog_errno(ret); >>> } >>> - ocfs2_inode_unlock(inode, 1); >>> + ocfs2_inode_unlock_tracker(inode, 1, &oh, had_lock); >>> cleanup_nolock: >>> brelse(di_bh); >>> brelse(xbs.xattr_bh); >>> _______________________________________________ Ocfs2-devel mailing list Ocfs2-devel@oss.oracle.com https://oss.oracle.com/mailman/listinfo/ocfs2-devel