@@ -1810,11 +1810,16 @@ int reiserfs_new_inode(struct reiserfs_transaction_handle *th,
TYPE_STAT_DATA, SD_SIZE, MAX_US_INT);
memcpy(INODE_PKEY(inode), &(ih.ih_key), KEY_SIZE);
args.dirid = le32_to_cpu(ih.ih_key.k_dir_id);
- if (insert_inode_locked4(inode, args.objectid,
- reiserfs_find_actor, &args) < 0) {
+
+ reiserfs_write_unlock(inode->i_sb);
+ err = insert_inode_locked4(inode, args.objectid,
+ reiserfs_find_actor, &args);
+ reiserfs_write_lock(inode->i_sb);
+ if (err) {
err = -EINVAL;
goto out_bad_inode;
}
+
if (old_format_only(sb))
/* not a perfect generation count, as object ids can be reused, but
** this is as good as reiserfs can do right now.
This is a note to let you know that I have just added a patch titled reiserfs: fix deadlock with nfs racing on create/lookup to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue This patch is scheduled to be released in version 3.8.13.4. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.8.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From b81e986fc2c5e10744f5310704a5de83c9606489 Mon Sep 17 00:00:00 2001 From: Jeff Mahoney <jeffm@suse.com> Date: Fri, 31 May 2013 15:51:17 -0400 Subject: reiserfs: fix deadlock with nfs racing on create/lookup commit a1457c0ce976bad1356b9b0437f2a5c3ab8a9cfc upstream. Reiserfs is currently able to be deadlocked by having two NFS clients where one has removed and recreated a file and another is accessing the file with an open file handle. If one client deletes and recreates a file with timing such that the recreated file obtains the same [dirid, objectid] pair as the original file while another client accesses the file via file handle, the create and lookup can race and deadlock if the lookup manages to create the in-memory inode first. The create thread, in insert_inode_locked4, will hold the write lock while waiting on the other inode to be unlocked. The lookup thread, anywhere in the iget path, will release and reacquire the write lock while it schedules. If it needs to reacquire the lock while the create thread has it, it will never be able to make forward progress because it needs to reacquire the lock before ultimately unlocking the inode. This patch drops the write lock across the insert_inode_locked4 call so that the ordering of inode_wait -> write lock is retained. Since this would have been the case before the BKL push-down, this is safe. Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- fs/reiserfs/inode.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) -- 1.8.1.2