This is a note to let you know that I've just added the patch titled
ext4: avoid excessive credit estimate in ext4_tmpfile()
to the 6.6-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:
ext4-avoid-excessive-credit-estimate-in-ext4_tmpfile.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit cb839779568509b327edb9a80e953450137ac909
Author: Jan Kara <jack@xxxxxxx>
Date: Thu Mar 7 12:53:20 2024 +0100
ext4: avoid excessive credit estimate in ext4_tmpfile()
[ Upstream commit 35a1f12f0ca857fee1d7a04ef52cbd5f1f84de13 ]
A user with minimum journal size (1024 blocks these days) complained
about the following error triggered by generic/697 test in
ext4_tmpfile():
run fstests generic/697 at 2024-02-28 05:34:46
JBD2: vfstest wants too many credits credits:260 rsv_credits:0 max:256
EXT4-fs error (device loop0) in __ext4_new_inode:1083: error 28
Indeed the credit estimate in ext4_tmpfile() is huge.
EXT4_MAXQUOTAS_INIT_BLOCKS() is 219, then 10 credits from ext4_tmpfile()
itself and then ext4_xattr_credits_for_new_inode() adds more credits
needed for security attributes and ACLs. Now the
EXT4_MAXQUOTAS_INIT_BLOCKS() is in fact unnecessary because we've
already initialized quotas with dquot_init() shortly before and so
EXT4_MAXQUOTAS_TRANS_BLOCKS() is enough (which boils down to 3 credits).
Fixes: af51a2ac36d1 ("ext4: ->tmpfile() support")
Signed-off-by: Jan Kara <jack@xxxxxxx>
Tested-by: Luis Henriques <lhenriques@xxxxxxx>
Tested-by: Disha Goel <disgoel@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240307115320.28949-1-jack@xxxxxxx
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index bbda587f76b85..a2ee882e5ebb0 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -2901,7 +2901,7 @@ static int ext4_tmpfile(struct mnt_idmap *idmap, struct inode *dir,
inode = ext4_new_inode_start_handle(idmap, dir, mode,
NULL, 0, NULL,
EXT4_HT_DIR,
- EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) +
+ EXT4_MAXQUOTAS_TRANS_BLOCKS(dir->i_sb) +
4 + EXT4_XATTR_TRANS_BLOCKS);
handle = ext4_journal_current_handle();
err = PTR_ERR(inode);
