This is a note to let you know that I've just added the patch titled
vfs: use RCU in ilookup
to the 6.11-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
vfs-use-rcu-in-ilookup.patch
and it can be found in the queue-6.11 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit b873dca73a94b7dfa98b81a4e4783ce9e0b2702c
Author: Mateusz Guzik <mjguzik@xxxxxxxxx>
Date: Mon Jul 15 09:13:24 2024 +0200
vfs: use RCU in ilookup
[ Upstream commit 122381a46954ad592ee93d7da2bef5074b396247 ]
A soft lockup in ilookup was reported when stress-testing a 512-way
system [1] (see [2] for full context) and it was verified that not
taking the lock shifts issues back to mm.
[1] https://lore.kernel.org/linux-mm/56865e57-c250-44da-9713-cf1404595bcc@xxxxxxx/
[2] https://lore.kernel.org/linux-mm/d2841226-e27b-4d3d-a578-63587a3aa4f3@xxxxxxx/
Signed-off-by: Mateusz Guzik <mjguzik@xxxxxxxxx>
Link: https://lore.kernel.org/r/20240715071324.265879-1-mjguzik@xxxxxxxxx
Reviewed-by: Jan Kara <jack@xxxxxxx>
Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/inode.c b/fs/inode.c
index 551ba352072fa..30d42ab137f0a 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1578,9 +1578,7 @@ struct inode *ilookup(struct super_block *sb, unsigned long ino)
struct hlist_head *head = inode_hashtable + hash(sb, ino);
struct inode *inode;
again:
- spin_lock(&inode_hash_lock);
- inode = find_inode_fast(sb, head, ino, true);
- spin_unlock(&inode_hash_lock);
+ inode = find_inode_fast(sb, head, ino, false);
if (inode) {
if (IS_ERR(inode))
