From: akpm@linux-foundation.org Subject: + vfs-fix-possible-deadlock-in-ext2-ext3-ext4-when-using-xattrs.patch added to -mm tree Date: Tue, 15 Apr 2008 11:04:21 -0700 Message-ID: <200804151804.m3FI4LYW007948@imap1.linux-foundation.org> Cc: jack@suse.cz, davej@redhat.com, linux-ext4@vger.kernel.org To: mm-commits@vger.kernel.org Return-path: Received: from smtp1.linux-foundation.org ([140.211.169.13]:50072 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752176AbYDOSEy (ORCPT ); Tue, 15 Apr 2008 14:04:54 -0400 Sender: linux-ext4-owner@vger.kernel.org List-ID: The patch titled vfs: fix possible deadlock in ext2, ext3, ext4 when using xattrs has been added to the -mm tree. Its filename is vfs-fix-possible-deadlock-in-ext2-ext3-ext4-when-using-xattrs.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: vfs: fix possible deadlock in ext2, ext3, ext4 when using xattrs From: Jan Kara mb_cache_entry_alloc() was allocating cache entries with GFP_KERNEL. But filesystems are calling this function while holding xattr_sem so possible recursion into the fs violates locking ordering of xattr_sem and transaction start / i_mutex for ext2-4. Change mb_cache_entry_alloc() so that filesystems can specify desired gfp mask and use GFP_NOFS from all of them. Signed-off-by: Jan Kara Reported-by: Dave Jones Cc: Signed-off-by: Andrew Morton --- fs/ext2/xattr.c | 2 +- fs/ext3/xattr.c | 2 +- fs/ext4/xattr.c | 2 +- fs/mbcache.c | 4 ++-- include/linux/mbcache.h | 2 +- 5 files changed, 6 insertions(+), 6 deletions(-) diff -puN fs/ext2/xattr.c~vfs-fix-possible-deadlock-in-ext2-ext3-ext4-when-using-xattrs fs/ext2/xattr.c --- a/fs/ext2/xattr.c~vfs-fix-possible-deadlock-in-ext2-ext3-ext4-when-using-xattrs +++ a/fs/ext2/xattr.c @@ -835,7 +835,7 @@ ext2_xattr_cache_insert(struct buffer_he struct mb_cache_entry *ce; int error; - ce = mb_cache_entry_alloc(ext2_xattr_cache); + ce = mb_cache_entry_alloc(ext2_xattr_cache, GFP_NOFS); if (!ce) return -ENOMEM; error = mb_cache_entry_insert(ce, bh->b_bdev, bh->b_blocknr, &hash); diff -puN fs/ext3/xattr.c~vfs-fix-possible-deadlock-in-ext2-ext3-ext4-when-using-xattrs fs/ext3/xattr.c --- a/fs/ext3/xattr.c~vfs-fix-possible-deadlock-in-ext2-ext3-ext4-when-using-xattrs +++ a/fs/ext3/xattr.c @@ -1126,7 +1126,7 @@ ext3_xattr_cache_insert(struct buffer_he struct mb_cache_entry *ce; int error; - ce = mb_cache_entry_alloc(ext3_xattr_cache); + ce = mb_cache_entry_alloc(ext3_xattr_cache, GFP_NOFS); if (!ce) { ea_bdebug(bh, "out of memory"); return; diff -puN fs/ext4/xattr.c~vfs-fix-possible-deadlock-in-ext2-ext3-ext4-when-using-xattrs fs/ext4/xattr.c --- a/fs/ext4/xattr.c~vfs-fix-possible-deadlock-in-ext2-ext3-ext4-when-using-xattrs +++ a/fs/ext4/xattr.c @@ -1386,7 +1386,7 @@ ext4_xattr_cache_insert(struct buffer_he struct mb_cache_entry *ce; int error; - ce = mb_cache_entry_alloc(ext4_xattr_cache); + ce = mb_cache_entry_alloc(ext4_xattr_cache, GFP_NOFS); if (!ce) { ea_bdebug(bh, "out of memory"); return; diff -puN fs/mbcache.c~vfs-fix-possible-deadlock-in-ext2-ext3-ext4-when-using-xattrs fs/mbcache.c --- a/fs/mbcache.c~vfs-fix-possible-deadlock-in-ext2-ext3-ext4-when-using-xattrs +++ a/fs/mbcache.c @@ -399,11 +399,11 @@ mb_cache_destroy(struct mb_cache *cache) * if no more memory was available. */ struct mb_cache_entry * -mb_cache_entry_alloc(struct mb_cache *cache) +mb_cache_entry_alloc(struct mb_cache *cache, gfp_t gfp_flags) { struct mb_cache_entry *ce; - ce = kmem_cache_alloc(cache->c_entry_cache, GFP_KERNEL); + ce = kmem_cache_alloc(cache->c_entry_cache, gfp_flags); if (ce) { atomic_inc(&cache->c_entry_count); INIT_LIST_HEAD(&ce->e_lru_list); diff -puN include/linux/mbcache.h~vfs-fix-possible-deadlock-in-ext2-ext3-ext4-when-using-xattrs include/linux/mbcache.h --- a/include/linux/mbcache.h~vfs-fix-possible-deadlock-in-ext2-ext3-ext4-when-using-xattrs +++ a/include/linux/mbcache.h @@ -34,7 +34,7 @@ void mb_cache_destroy(struct mb_cache *) /* Functions on cache entries */ -struct mb_cache_entry *mb_cache_entry_alloc(struct mb_cache *); +struct mb_cache_entry *mb_cache_entry_alloc(struct mb_cache *, gfp_t); int mb_cache_entry_insert(struct mb_cache_entry *, struct block_device *, sector_t, unsigned int[]); void mb_cache_entry_release(struct mb_cache_entry *); _ Patches currently in -mm which might be from jack@suse.cz are vfs-fix-possible-deadlock-in-ext2-ext3-ext4-when-using-xattrs.patch v4l-fix-concurrent-read-from-proc-videocodecs.patch git-udf.patch git-ocfs2.patch vfs-fix-lock-inversion-in-drop_pagecache_sb.patch vfs-skip-inodes-without-pages-to-free-in-drop_pagecache_sb.patch quota-do-not-allow-setting-of-quota-limits-to-too-high-values.patch quota-remove-superfluous-dquot_off-in-fs-namespacec.patch quota-various-style-cleanups.patch quota-various-style-cleanups-checkpatch-fixes.patch quota-quota-core-changes-for-quotaon-on-remount.patch quota-quota-core-changes-for-quotaon-on-remount-quota-ext3-make-ext3-handle-quotaon-on-remount.patch quota-quota-core-changes-for-quotaon-on-remount-quota-ext3-make-ext3-handle-quotaon-on-remount-checkpatch-fixes.patch quota-quota-core-changes-for-quotaon-on-remount-quota-ext4-make-ext4-handle-quotaon-on-remount.patch quota-quota-core-changes-for-quotaon-on-remount-quota-ext4-make-ext4-handle-quotaon-on-remount-checkpatch-fixes.patch quota-quota-core-changes-for-quotaon-on-remount-quota-reiserfs-make-reiserfs-handle-quotaon-on-remount.patch ext3-fdatasync-should-skip-metadata-writeout-when-overwriting.patch ext3-fix-update-of-mtime-and-ctime-on-rename.patch ext3-fix-hang-on-umount-with-quotas-when-journal-is-aborted.patch reiserfs-fix-hang-on-umount-with-quotas-when-journal-is-aborted.patch ext4-fix-update-of-mtime-and-ctime-on-rename.patch ext4-fix-hang-on-umount-with-quotas-when-journal-is-aborted.patch quota-le_add_cpu-conversion.patch