The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x 46f881b5b1758dc4a35fba4a643c10717d0cf427
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023072433-obsessed-limeade-e4b9@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
46f881b5b175 ("jbd2: fix a race when checking checkpoint buffer busy")
b98dba273a0e ("jbd2: remove journal_clean_one_cp_list()")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 46f881b5b1758dc4a35fba4a643c10717d0cf427 Mon Sep 17 00:00:00 2001
From: Zhang Yi <yi.zhang(a)huawei.com>
Date: Tue, 6 Jun 2023 21:59:27 +0800
Subject: [PATCH] jbd2: fix a race when checking checkpoint buffer busy
Before removing checkpoint buffer from the t_checkpoint_list, we have to
check both BH_Dirty and BH_Lock bits together to distinguish buffers
have not been or were being written back. But __cp_buffer_busy() checks
them separately, it first check lock state and then check dirty, the
window between these two checks could be raced by writing back
procedure, which locks buffer and clears buffer dirty before I/O
completes. So it cannot guarantee checkpointing buffers been written
back to disk if some error happens later. Finally, it may clean
checkpoint transactions and lead to inconsistent filesystem.
jbd2_journal_forget() and __journal_try_to_free_buffer() also have the
same problem (journal_unmap_buffer() escape from this issue since it's
running under the buffer lock), so fix them through introducing a new
helper to try holding the buffer lock and remove really clean buffer.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217490
Cc: stable(a)vger.kernel.org
Suggested-by: Jan Kara <jack(a)suse.cz>
Signed-off-by: Zhang Yi <yi.zhang(a)huawei.com>
Reviewed-by: Jan Kara <jack(a)suse.cz>
Link: https://lore.kernel.org/r/20230606135928.434610-6-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso(a)mit.edu>
diff --git a/fs/jbd2/checkpoint.c b/fs/jbd2/checkpoint.c
index 42b34cab64fb..9ec91017a7f3 100644
--- a/fs/jbd2/checkpoint.c
+++ b/fs/jbd2/checkpoint.c
@@ -376,11 +376,15 @@ static unsigned long journal_shrink_one_cp_list(struct journal_head *jh,
jh = next_jh;
next_jh = jh->b_cpnext;
- if (!destroy && __cp_buffer_busy(jh))
- continue;
+ if (destroy) {
+ ret = __jbd2_journal_remove_checkpoint(jh);
+ } else {
+ ret = jbd2_journal_try_remove_checkpoint(jh);
+ if (ret < 0)
+ continue;
+ }
nr_freed++;
- ret = __jbd2_journal_remove_checkpoint(jh);
if (ret) {
*released = true;
break;
@@ -616,6 +620,34 @@ int __jbd2_journal_remove_checkpoint(struct journal_head *jh)
return 1;
}
+/*
+ * Check the checkpoint buffer and try to remove it from the checkpoint
+ * list if it's clean. Returns -EBUSY if it is not clean, returns 1 if
+ * it frees the transaction, 0 otherwise.
+ *
+ * This function is called with j_list_lock held.
+ */
+int jbd2_journal_try_remove_checkpoint(struct journal_head *jh)
+{
+ struct buffer_head *bh = jh2bh(jh);
+
+ if (!trylock_buffer(bh))
+ return -EBUSY;
+ if (buffer_dirty(bh)) {
+ unlock_buffer(bh);
+ return -EBUSY;
+ }
+ unlock_buffer(bh);
+
+ /*
+ * Buffer is clean and the IO has finished (we held the buffer
+ * lock) so the checkpoint is done. We can safely remove the
+ * buffer from this transaction.
+ */
+ JBUFFER_TRACE(jh, "remove from checkpoint list");
+ return __jbd2_journal_remove_checkpoint(jh);
+}
+
/*
* journal_insert_checkpoint: put a committed buffer onto a checkpoint
* list so that we know when it is safe to clean the transaction out of
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index 18611241f451..6ef5022949c4 100644
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -1784,8 +1784,7 @@ int jbd2_journal_forget(handle_t *handle, struct buffer_head *bh)
* Otherwise, if the buffer has been written to disk,
* it is safe to remove the checkpoint and drop it.
*/
- if (!buffer_dirty(bh)) {
- __jbd2_journal_remove_checkpoint(jh);
+ if (jbd2_journal_try_remove_checkpoint(jh) >= 0) {
spin_unlock(&journal->j_list_lock);
goto drop;
}
@@ -2112,20 +2111,14 @@ __journal_try_to_free_buffer(journal_t *journal, struct buffer_head *bh)
jh = bh2jh(bh);
- if (buffer_locked(bh) || buffer_dirty(bh))
- goto out;
-
if (jh->b_next_transaction != NULL || jh->b_transaction != NULL)
- goto out;
+ return;
spin_lock(&journal->j_list_lock);
- if (jh->b_cp_transaction != NULL) {
- /* written-back checkpointed metadata buffer */
- JBUFFER_TRACE(jh, "remove from checkpoint list");
- __jbd2_journal_remove_checkpoint(jh);
- }
+ /* Remove written-back checkpointed metadata buffer */
+ if (jh->b_cp_transaction != NULL)
+ jbd2_journal_try_remove_checkpoint(jh);
spin_unlock(&journal->j_list_lock);
-out:
return;
}
diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index bd660aac8e07..44c298aa58d4 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -1443,6 +1443,7 @@ extern void jbd2_journal_commit_transaction(journal_t *);
void __jbd2_journal_clean_checkpoint_list(journal_t *journal, bool destroy);
unsigned long jbd2_journal_shrink_checkpoint_list(journal_t *journal, unsigned long *nr_to_scan);
int __jbd2_journal_remove_checkpoint(struct journal_head *);
+int jbd2_journal_try_remove_checkpoint(struct journal_head *jh);
void jbd2_journal_destroy_checkpoint(journal_t *journal);
void __jbd2_journal_insert_checkpoint(struct journal_head *, transaction_t *);
The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.19.y
git checkout FETCH_HEAD
git cherry-pick -x 5d5460fa7932bed3a9082a6a8852cfbdb46acbe8
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023072434-stylist-reflex-c474@gregkh' --subject-prefix 'PATCH 4.19.y' HEAD^..
Possible dependencies:
5d5460fa7932 ("ext4: fix off by one issue in ext4_mb_choose_next_group_best_avail()")
f52f3d2b9fba ("ext4: Give symbolic names to mballoc criterias")
7e170922f06b ("ext4: Add allocation criteria 1.5 (CR1_5)")
1b4200112108 ("ext4: Avoid scanning smaller extents in BG during CR1")
3ef5d2638796 ("ext4: Add counter to track successful allocation of goal length")
fdd9a00943a5 ("ext4: Add per CR extent scanned counter")
4eb7a4a1a33b ("ext4: Convert mballoc cr (criteria) to enum")
c3defd99d58c ("ext4: treat stripe in block unit")
361eb69fc99f ("ext4: Remove the logic to trim inode PAs")
3872778664e3 ("ext4: Use rbtrees to manage PAs instead of inode i_prealloc_list")
a8e38fd37cff ("ext4: Convert pa->pa_inode_list and pa->pa_obj_lock into a union")
93cdf49f6eca ("ext4: Fix best extent lstart adjustment logic in ext4_mb_new_inode_pa()")
0830344c953a ("ext4: Abstract out overlap fix/check logic in ext4_mb_normalize_request()")
7692094ac513 ("ext4: Move overlap assert logic into a separate function")
bcf434992145 ("ext4: Refactor code in ext4_mb_normalize_request() and ext4_mb_use_preallocated()")
e86a718228b6 ("ext4: Stop searching if PA doesn't satisfy non-extent file")
91a48aaf59d0 ("ext4: avoid unnecessary pointer dereference in ext4_mb_normalize_request")
83e80a6e3543 ("ext4: use buckets for cr 1 block scan instead of rbtree")
4fca50d440cc ("ext4: make mballoc try target group first even with mb_optimize_scan")
cf4ff938b47f ("ext4: correct the judgment of BUG in ext4_mb_normalize_request")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 5d5460fa7932bed3a9082a6a8852cfbdb46acbe8 Mon Sep 17 00:00:00 2001
From: Ojaswin Mujoo <ojaswin(a)linux.ibm.com>
Date: Fri, 9 Jun 2023 16:04:03 +0530
Subject: [PATCH] ext4: fix off by one issue in
ext4_mb_choose_next_group_best_avail()
In ext4_mb_choose_next_group_best_avail(), we want the start order to be
1 less than goal length and the min_order to be, at max, 1 more than the
original length. This commit fixes an off by one issue that arose due to
the fact that 1 << fls(n) > (n).
After all the processing:
order = 1 order below goal len
min_order = maximum of the three:-
- order - trim_order
- 1 order below B2C(s_stripe)
- 1 order above original len
Cc: stable(a)kernel.org
Fixes: 33122aa930 ("ext4: Add allocation criteria 1.5 (CR1_5)")
Signed-off-by: Ojaswin Mujoo <ojaswin(a)linux.ibm.com>
Link: https://lore.kernel.org/r/20230609103403.112807-1-ojaswin@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso(a)mit.edu>
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index a2475b8c9fb5..456150ef6111 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -1006,14 +1006,11 @@ static void ext4_mb_choose_next_group_best_avail(struct ext4_allocation_context
* fls() instead since we need to know the actual length while modifying
* goal length.
*/
- order = fls(ac->ac_g_ex.fe_len);
+ order = fls(ac->ac_g_ex.fe_len) - 1;
min_order = order - sbi->s_mb_best_avail_max_trim_order;
if (min_order < 0)
min_order = 0;
- if (1 << min_order < ac->ac_o_ex.fe_len)
- min_order = fls(ac->ac_o_ex.fe_len) + 1;
-
if (sbi->s_stripe > 0) {
/*
* We are assuming that stripe size is always a multiple of
@@ -1021,9 +1018,16 @@ static void ext4_mb_choose_next_group_best_avail(struct ext4_allocation_context
*/
num_stripe_clusters = EXT4_NUM_B2C(sbi, sbi->s_stripe);
if (1 << min_order < num_stripe_clusters)
- min_order = fls(num_stripe_clusters);
+ /*
+ * We consider 1 order less because later we round
+ * up the goal len to num_stripe_clusters
+ */
+ min_order = fls(num_stripe_clusters) - 1;
}
+ if (1 << min_order < ac->ac_o_ex.fe_len)
+ min_order = fls(ac->ac_o_ex.fe_len);
+
for (i = order; i >= min_order; i--) {
int frag_order;
/*
The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x 5d5460fa7932bed3a9082a6a8852cfbdb46acbe8
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023072427-curler-operate-a8d0@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
5d5460fa7932 ("ext4: fix off by one issue in ext4_mb_choose_next_group_best_avail()")
f52f3d2b9fba ("ext4: Give symbolic names to mballoc criterias")
7e170922f06b ("ext4: Add allocation criteria 1.5 (CR1_5)")
1b4200112108 ("ext4: Avoid scanning smaller extents in BG during CR1")
3ef5d2638796 ("ext4: Add counter to track successful allocation of goal length")
fdd9a00943a5 ("ext4: Add per CR extent scanned counter")
4eb7a4a1a33b ("ext4: Convert mballoc cr (criteria) to enum")
c3defd99d58c ("ext4: treat stripe in block unit")
361eb69fc99f ("ext4: Remove the logic to trim inode PAs")
3872778664e3 ("ext4: Use rbtrees to manage PAs instead of inode i_prealloc_list")
a8e38fd37cff ("ext4: Convert pa->pa_inode_list and pa->pa_obj_lock into a union")
93cdf49f6eca ("ext4: Fix best extent lstart adjustment logic in ext4_mb_new_inode_pa()")
0830344c953a ("ext4: Abstract out overlap fix/check logic in ext4_mb_normalize_request()")
7692094ac513 ("ext4: Move overlap assert logic into a separate function")
bcf434992145 ("ext4: Refactor code in ext4_mb_normalize_request() and ext4_mb_use_preallocated()")
e86a718228b6 ("ext4: Stop searching if PA doesn't satisfy non-extent file")
91a48aaf59d0 ("ext4: avoid unnecessary pointer dereference in ext4_mb_normalize_request")
83e80a6e3543 ("ext4: use buckets for cr 1 block scan instead of rbtree")
4fca50d440cc ("ext4: make mballoc try target group first even with mb_optimize_scan")
cf4ff938b47f ("ext4: correct the judgment of BUG in ext4_mb_normalize_request")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 5d5460fa7932bed3a9082a6a8852cfbdb46acbe8 Mon Sep 17 00:00:00 2001
From: Ojaswin Mujoo <ojaswin(a)linux.ibm.com>
Date: Fri, 9 Jun 2023 16:04:03 +0530
Subject: [PATCH] ext4: fix off by one issue in
ext4_mb_choose_next_group_best_avail()
In ext4_mb_choose_next_group_best_avail(), we want the start order to be
1 less than goal length and the min_order to be, at max, 1 more than the
original length. This commit fixes an off by one issue that arose due to
the fact that 1 << fls(n) > (n).
After all the processing:
order = 1 order below goal len
min_order = maximum of the three:-
- order - trim_order
- 1 order below B2C(s_stripe)
- 1 order above original len
Cc: stable(a)kernel.org
Fixes: 33122aa930 ("ext4: Add allocation criteria 1.5 (CR1_5)")
Signed-off-by: Ojaswin Mujoo <ojaswin(a)linux.ibm.com>
Link: https://lore.kernel.org/r/20230609103403.112807-1-ojaswin@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso(a)mit.edu>
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index a2475b8c9fb5..456150ef6111 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -1006,14 +1006,11 @@ static void ext4_mb_choose_next_group_best_avail(struct ext4_allocation_context
* fls() instead since we need to know the actual length while modifying
* goal length.
*/
- order = fls(ac->ac_g_ex.fe_len);
+ order = fls(ac->ac_g_ex.fe_len) - 1;
min_order = order - sbi->s_mb_best_avail_max_trim_order;
if (min_order < 0)
min_order = 0;
- if (1 << min_order < ac->ac_o_ex.fe_len)
- min_order = fls(ac->ac_o_ex.fe_len) + 1;
-
if (sbi->s_stripe > 0) {
/*
* We are assuming that stripe size is always a multiple of
@@ -1021,9 +1018,16 @@ static void ext4_mb_choose_next_group_best_avail(struct ext4_allocation_context
*/
num_stripe_clusters = EXT4_NUM_B2C(sbi, sbi->s_stripe);
if (1 << min_order < num_stripe_clusters)
- min_order = fls(num_stripe_clusters);
+ /*
+ * We consider 1 order less because later we round
+ * up the goal len to num_stripe_clusters
+ */
+ min_order = fls(num_stripe_clusters) - 1;
}
+ if (1 << min_order < ac->ac_o_ex.fe_len)
+ min_order = fls(ac->ac_o_ex.fe_len);
+
for (i = order; i >= min_order; i--) {
int frag_order;
/*
The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 46f881b5b1758dc4a35fba4a643c10717d0cf427
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023072424-dejected-raisin-2dd7@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
46f881b5b175 ("jbd2: fix a race when checking checkpoint buffer busy")
b98dba273a0e ("jbd2: remove journal_clean_one_cp_list()")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 46f881b5b1758dc4a35fba4a643c10717d0cf427 Mon Sep 17 00:00:00 2001
From: Zhang Yi <yi.zhang(a)huawei.com>
Date: Tue, 6 Jun 2023 21:59:27 +0800
Subject: [PATCH] jbd2: fix a race when checking checkpoint buffer busy
Before removing checkpoint buffer from the t_checkpoint_list, we have to
check both BH_Dirty and BH_Lock bits together to distinguish buffers
have not been or were being written back. But __cp_buffer_busy() checks
them separately, it first check lock state and then check dirty, the
window between these two checks could be raced by writing back
procedure, which locks buffer and clears buffer dirty before I/O
completes. So it cannot guarantee checkpointing buffers been written
back to disk if some error happens later. Finally, it may clean
checkpoint transactions and lead to inconsistent filesystem.
jbd2_journal_forget() and __journal_try_to_free_buffer() also have the
same problem (journal_unmap_buffer() escape from this issue since it's
running under the buffer lock), so fix them through introducing a new
helper to try holding the buffer lock and remove really clean buffer.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217490
Cc: stable(a)vger.kernel.org
Suggested-by: Jan Kara <jack(a)suse.cz>
Signed-off-by: Zhang Yi <yi.zhang(a)huawei.com>
Reviewed-by: Jan Kara <jack(a)suse.cz>
Link: https://lore.kernel.org/r/20230606135928.434610-6-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso(a)mit.edu>
diff --git a/fs/jbd2/checkpoint.c b/fs/jbd2/checkpoint.c
index 42b34cab64fb..9ec91017a7f3 100644
--- a/fs/jbd2/checkpoint.c
+++ b/fs/jbd2/checkpoint.c
@@ -376,11 +376,15 @@ static unsigned long journal_shrink_one_cp_list(struct journal_head *jh,
jh = next_jh;
next_jh = jh->b_cpnext;
- if (!destroy && __cp_buffer_busy(jh))
- continue;
+ if (destroy) {
+ ret = __jbd2_journal_remove_checkpoint(jh);
+ } else {
+ ret = jbd2_journal_try_remove_checkpoint(jh);
+ if (ret < 0)
+ continue;
+ }
nr_freed++;
- ret = __jbd2_journal_remove_checkpoint(jh);
if (ret) {
*released = true;
break;
@@ -616,6 +620,34 @@ int __jbd2_journal_remove_checkpoint(struct journal_head *jh)
return 1;
}
+/*
+ * Check the checkpoint buffer and try to remove it from the checkpoint
+ * list if it's clean. Returns -EBUSY if it is not clean, returns 1 if
+ * it frees the transaction, 0 otherwise.
+ *
+ * This function is called with j_list_lock held.
+ */
+int jbd2_journal_try_remove_checkpoint(struct journal_head *jh)
+{
+ struct buffer_head *bh = jh2bh(jh);
+
+ if (!trylock_buffer(bh))
+ return -EBUSY;
+ if (buffer_dirty(bh)) {
+ unlock_buffer(bh);
+ return -EBUSY;
+ }
+ unlock_buffer(bh);
+
+ /*
+ * Buffer is clean and the IO has finished (we held the buffer
+ * lock) so the checkpoint is done. We can safely remove the
+ * buffer from this transaction.
+ */
+ JBUFFER_TRACE(jh, "remove from checkpoint list");
+ return __jbd2_journal_remove_checkpoint(jh);
+}
+
/*
* journal_insert_checkpoint: put a committed buffer onto a checkpoint
* list so that we know when it is safe to clean the transaction out of
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index 18611241f451..6ef5022949c4 100644
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -1784,8 +1784,7 @@ int jbd2_journal_forget(handle_t *handle, struct buffer_head *bh)
* Otherwise, if the buffer has been written to disk,
* it is safe to remove the checkpoint and drop it.
*/
- if (!buffer_dirty(bh)) {
- __jbd2_journal_remove_checkpoint(jh);
+ if (jbd2_journal_try_remove_checkpoint(jh) >= 0) {
spin_unlock(&journal->j_list_lock);
goto drop;
}
@@ -2112,20 +2111,14 @@ __journal_try_to_free_buffer(journal_t *journal, struct buffer_head *bh)
jh = bh2jh(bh);
- if (buffer_locked(bh) || buffer_dirty(bh))
- goto out;
-
if (jh->b_next_transaction != NULL || jh->b_transaction != NULL)
- goto out;
+ return;
spin_lock(&journal->j_list_lock);
- if (jh->b_cp_transaction != NULL) {
- /* written-back checkpointed metadata buffer */
- JBUFFER_TRACE(jh, "remove from checkpoint list");
- __jbd2_journal_remove_checkpoint(jh);
- }
+ /* Remove written-back checkpointed metadata buffer */
+ if (jh->b_cp_transaction != NULL)
+ jbd2_journal_try_remove_checkpoint(jh);
spin_unlock(&journal->j_list_lock);
-out:
return;
}
diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index bd660aac8e07..44c298aa58d4 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -1443,6 +1443,7 @@ extern void jbd2_journal_commit_transaction(journal_t *);
void __jbd2_journal_clean_checkpoint_list(journal_t *journal, bool destroy);
unsigned long jbd2_journal_shrink_checkpoint_list(journal_t *journal, unsigned long *nr_to_scan);
int __jbd2_journal_remove_checkpoint(struct journal_head *);
+int jbd2_journal_try_remove_checkpoint(struct journal_head *jh);
void jbd2_journal_destroy_checkpoint(journal_t *journal);
void __jbd2_journal_insert_checkpoint(struct journal_head *, transaction_t *);
The patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x 5d5460fa7932bed3a9082a6a8852cfbdb46acbe8
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023072419-silt-kinswoman-c896@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..
Possible dependencies:
5d5460fa7932 ("ext4: fix off by one issue in ext4_mb_choose_next_group_best_avail()")
f52f3d2b9fba ("ext4: Give symbolic names to mballoc criterias")
7e170922f06b ("ext4: Add allocation criteria 1.5 (CR1_5)")
1b4200112108 ("ext4: Avoid scanning smaller extents in BG during CR1")
3ef5d2638796 ("ext4: Add counter to track successful allocation of goal length")
fdd9a00943a5 ("ext4: Add per CR extent scanned counter")
4eb7a4a1a33b ("ext4: Convert mballoc cr (criteria) to enum")
c3defd99d58c ("ext4: treat stripe in block unit")
361eb69fc99f ("ext4: Remove the logic to trim inode PAs")
3872778664e3 ("ext4: Use rbtrees to manage PAs instead of inode i_prealloc_list")
a8e38fd37cff ("ext4: Convert pa->pa_inode_list and pa->pa_obj_lock into a union")
93cdf49f6eca ("ext4: Fix best extent lstart adjustment logic in ext4_mb_new_inode_pa()")
0830344c953a ("ext4: Abstract out overlap fix/check logic in ext4_mb_normalize_request()")
7692094ac513 ("ext4: Move overlap assert logic into a separate function")
bcf434992145 ("ext4: Refactor code in ext4_mb_normalize_request() and ext4_mb_use_preallocated()")
e86a718228b6 ("ext4: Stop searching if PA doesn't satisfy non-extent file")
91a48aaf59d0 ("ext4: avoid unnecessary pointer dereference in ext4_mb_normalize_request")
83e80a6e3543 ("ext4: use buckets for cr 1 block scan instead of rbtree")
4fca50d440cc ("ext4: make mballoc try target group first even with mb_optimize_scan")
cf4ff938b47f ("ext4: correct the judgment of BUG in ext4_mb_normalize_request")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 5d5460fa7932bed3a9082a6a8852cfbdb46acbe8 Mon Sep 17 00:00:00 2001
From: Ojaswin Mujoo <ojaswin(a)linux.ibm.com>
Date: Fri, 9 Jun 2023 16:04:03 +0530
Subject: [PATCH] ext4: fix off by one issue in
ext4_mb_choose_next_group_best_avail()
In ext4_mb_choose_next_group_best_avail(), we want the start order to be
1 less than goal length and the min_order to be, at max, 1 more than the
original length. This commit fixes an off by one issue that arose due to
the fact that 1 << fls(n) > (n).
After all the processing:
order = 1 order below goal len
min_order = maximum of the three:-
- order - trim_order
- 1 order below B2C(s_stripe)
- 1 order above original len
Cc: stable(a)kernel.org
Fixes: 33122aa930 ("ext4: Add allocation criteria 1.5 (CR1_5)")
Signed-off-by: Ojaswin Mujoo <ojaswin(a)linux.ibm.com>
Link: https://lore.kernel.org/r/20230609103403.112807-1-ojaswin@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso(a)mit.edu>
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index a2475b8c9fb5..456150ef6111 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -1006,14 +1006,11 @@ static void ext4_mb_choose_next_group_best_avail(struct ext4_allocation_context
* fls() instead since we need to know the actual length while modifying
* goal length.
*/
- order = fls(ac->ac_g_ex.fe_len);
+ order = fls(ac->ac_g_ex.fe_len) - 1;
min_order = order - sbi->s_mb_best_avail_max_trim_order;
if (min_order < 0)
min_order = 0;
- if (1 << min_order < ac->ac_o_ex.fe_len)
- min_order = fls(ac->ac_o_ex.fe_len) + 1;
-
if (sbi->s_stripe > 0) {
/*
* We are assuming that stripe size is always a multiple of
@@ -1021,9 +1018,16 @@ static void ext4_mb_choose_next_group_best_avail(struct ext4_allocation_context
*/
num_stripe_clusters = EXT4_NUM_B2C(sbi, sbi->s_stripe);
if (1 << min_order < num_stripe_clusters)
- min_order = fls(num_stripe_clusters);
+ /*
+ * We consider 1 order less because later we round
+ * up the goal len to num_stripe_clusters
+ */
+ min_order = fls(num_stripe_clusters) - 1;
}
+ if (1 << min_order < ac->ac_o_ex.fe_len)
+ min_order = fls(ac->ac_o_ex.fe_len);
+
for (i = order; i >= min_order; i--) {
int frag_order;
/*
The patch below does not apply to the 6.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.4.y
git checkout FETCH_HEAD
git cherry-pick -x 46f881b5b1758dc4a35fba4a643c10717d0cf427
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023072415-dyslexic-spoilage-fb58@gregkh' --subject-prefix 'PATCH 6.4.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 46f881b5b1758dc4a35fba4a643c10717d0cf427 Mon Sep 17 00:00:00 2001
From: Zhang Yi <yi.zhang(a)huawei.com>
Date: Tue, 6 Jun 2023 21:59:27 +0800
Subject: [PATCH] jbd2: fix a race when checking checkpoint buffer busy
Before removing checkpoint buffer from the t_checkpoint_list, we have to
check both BH_Dirty and BH_Lock bits together to distinguish buffers
have not been or were being written back. But __cp_buffer_busy() checks
them separately, it first check lock state and then check dirty, the
window between these two checks could be raced by writing back
procedure, which locks buffer and clears buffer dirty before I/O
completes. So it cannot guarantee checkpointing buffers been written
back to disk if some error happens later. Finally, it may clean
checkpoint transactions and lead to inconsistent filesystem.
jbd2_journal_forget() and __journal_try_to_free_buffer() also have the
same problem (journal_unmap_buffer() escape from this issue since it's
running under the buffer lock), so fix them through introducing a new
helper to try holding the buffer lock and remove really clean buffer.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217490
Cc: stable(a)vger.kernel.org
Suggested-by: Jan Kara <jack(a)suse.cz>
Signed-off-by: Zhang Yi <yi.zhang(a)huawei.com>
Reviewed-by: Jan Kara <jack(a)suse.cz>
Link: https://lore.kernel.org/r/20230606135928.434610-6-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso(a)mit.edu>
diff --git a/fs/jbd2/checkpoint.c b/fs/jbd2/checkpoint.c
index 42b34cab64fb..9ec91017a7f3 100644
--- a/fs/jbd2/checkpoint.c
+++ b/fs/jbd2/checkpoint.c
@@ -376,11 +376,15 @@ static unsigned long journal_shrink_one_cp_list(struct journal_head *jh,
jh = next_jh;
next_jh = jh->b_cpnext;
- if (!destroy && __cp_buffer_busy(jh))
- continue;
+ if (destroy) {
+ ret = __jbd2_journal_remove_checkpoint(jh);
+ } else {
+ ret = jbd2_journal_try_remove_checkpoint(jh);
+ if (ret < 0)
+ continue;
+ }
nr_freed++;
- ret = __jbd2_journal_remove_checkpoint(jh);
if (ret) {
*released = true;
break;
@@ -616,6 +620,34 @@ int __jbd2_journal_remove_checkpoint(struct journal_head *jh)
return 1;
}
+/*
+ * Check the checkpoint buffer and try to remove it from the checkpoint
+ * list if it's clean. Returns -EBUSY if it is not clean, returns 1 if
+ * it frees the transaction, 0 otherwise.
+ *
+ * This function is called with j_list_lock held.
+ */
+int jbd2_journal_try_remove_checkpoint(struct journal_head *jh)
+{
+ struct buffer_head *bh = jh2bh(jh);
+
+ if (!trylock_buffer(bh))
+ return -EBUSY;
+ if (buffer_dirty(bh)) {
+ unlock_buffer(bh);
+ return -EBUSY;
+ }
+ unlock_buffer(bh);
+
+ /*
+ * Buffer is clean and the IO has finished (we held the buffer
+ * lock) so the checkpoint is done. We can safely remove the
+ * buffer from this transaction.
+ */
+ JBUFFER_TRACE(jh, "remove from checkpoint list");
+ return __jbd2_journal_remove_checkpoint(jh);
+}
+
/*
* journal_insert_checkpoint: put a committed buffer onto a checkpoint
* list so that we know when it is safe to clean the transaction out of
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index 18611241f451..6ef5022949c4 100644
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -1784,8 +1784,7 @@ int jbd2_journal_forget(handle_t *handle, struct buffer_head *bh)
* Otherwise, if the buffer has been written to disk,
* it is safe to remove the checkpoint and drop it.
*/
- if (!buffer_dirty(bh)) {
- __jbd2_journal_remove_checkpoint(jh);
+ if (jbd2_journal_try_remove_checkpoint(jh) >= 0) {
spin_unlock(&journal->j_list_lock);
goto drop;
}
@@ -2112,20 +2111,14 @@ __journal_try_to_free_buffer(journal_t *journal, struct buffer_head *bh)
jh = bh2jh(bh);
- if (buffer_locked(bh) || buffer_dirty(bh))
- goto out;
-
if (jh->b_next_transaction != NULL || jh->b_transaction != NULL)
- goto out;
+ return;
spin_lock(&journal->j_list_lock);
- if (jh->b_cp_transaction != NULL) {
- /* written-back checkpointed metadata buffer */
- JBUFFER_TRACE(jh, "remove from checkpoint list");
- __jbd2_journal_remove_checkpoint(jh);
- }
+ /* Remove written-back checkpointed metadata buffer */
+ if (jh->b_cp_transaction != NULL)
+ jbd2_journal_try_remove_checkpoint(jh);
spin_unlock(&journal->j_list_lock);
-out:
return;
}
diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index bd660aac8e07..44c298aa58d4 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -1443,6 +1443,7 @@ extern void jbd2_journal_commit_transaction(journal_t *);
void __jbd2_journal_clean_checkpoint_list(journal_t *journal, bool destroy);
unsigned long jbd2_journal_shrink_checkpoint_list(journal_t *journal, unsigned long *nr_to_scan);
int __jbd2_journal_remove_checkpoint(struct journal_head *);
+int jbd2_journal_try_remove_checkpoint(struct journal_head *jh);
void jbd2_journal_destroy_checkpoint(journal_t *journal);
void __jbd2_journal_insert_checkpoint(struct journal_head *, transaction_t *);
The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x 5d5460fa7932bed3a9082a6a8852cfbdb46acbe8
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023072412-raft-circle-8700@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
5d5460fa7932 ("ext4: fix off by one issue in ext4_mb_choose_next_group_best_avail()")
f52f3d2b9fba ("ext4: Give symbolic names to mballoc criterias")
7e170922f06b ("ext4: Add allocation criteria 1.5 (CR1_5)")
1b4200112108 ("ext4: Avoid scanning smaller extents in BG during CR1")
3ef5d2638796 ("ext4: Add counter to track successful allocation of goal length")
fdd9a00943a5 ("ext4: Add per CR extent scanned counter")
4eb7a4a1a33b ("ext4: Convert mballoc cr (criteria) to enum")
c3defd99d58c ("ext4: treat stripe in block unit")
361eb69fc99f ("ext4: Remove the logic to trim inode PAs")
3872778664e3 ("ext4: Use rbtrees to manage PAs instead of inode i_prealloc_list")
a8e38fd37cff ("ext4: Convert pa->pa_inode_list and pa->pa_obj_lock into a union")
93cdf49f6eca ("ext4: Fix best extent lstart adjustment logic in ext4_mb_new_inode_pa()")
0830344c953a ("ext4: Abstract out overlap fix/check logic in ext4_mb_normalize_request()")
7692094ac513 ("ext4: Move overlap assert logic into a separate function")
bcf434992145 ("ext4: Refactor code in ext4_mb_normalize_request() and ext4_mb_use_preallocated()")
e86a718228b6 ("ext4: Stop searching if PA doesn't satisfy non-extent file")
91a48aaf59d0 ("ext4: avoid unnecessary pointer dereference in ext4_mb_normalize_request")
83e80a6e3543 ("ext4: use buckets for cr 1 block scan instead of rbtree")
4fca50d440cc ("ext4: make mballoc try target group first even with mb_optimize_scan")
cf4ff938b47f ("ext4: correct the judgment of BUG in ext4_mb_normalize_request")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 5d5460fa7932bed3a9082a6a8852cfbdb46acbe8 Mon Sep 17 00:00:00 2001
From: Ojaswin Mujoo <ojaswin(a)linux.ibm.com>
Date: Fri, 9 Jun 2023 16:04:03 +0530
Subject: [PATCH] ext4: fix off by one issue in
ext4_mb_choose_next_group_best_avail()
In ext4_mb_choose_next_group_best_avail(), we want the start order to be
1 less than goal length and the min_order to be, at max, 1 more than the
original length. This commit fixes an off by one issue that arose due to
the fact that 1 << fls(n) > (n).
After all the processing:
order = 1 order below goal len
min_order = maximum of the three:-
- order - trim_order
- 1 order below B2C(s_stripe)
- 1 order above original len
Cc: stable(a)kernel.org
Fixes: 33122aa930 ("ext4: Add allocation criteria 1.5 (CR1_5)")
Signed-off-by: Ojaswin Mujoo <ojaswin(a)linux.ibm.com>
Link: https://lore.kernel.org/r/20230609103403.112807-1-ojaswin@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso(a)mit.edu>
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index a2475b8c9fb5..456150ef6111 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -1006,14 +1006,11 @@ static void ext4_mb_choose_next_group_best_avail(struct ext4_allocation_context
* fls() instead since we need to know the actual length while modifying
* goal length.
*/
- order = fls(ac->ac_g_ex.fe_len);
+ order = fls(ac->ac_g_ex.fe_len) - 1;
min_order = order - sbi->s_mb_best_avail_max_trim_order;
if (min_order < 0)
min_order = 0;
- if (1 << min_order < ac->ac_o_ex.fe_len)
- min_order = fls(ac->ac_o_ex.fe_len) + 1;
-
if (sbi->s_stripe > 0) {
/*
* We are assuming that stripe size is always a multiple of
@@ -1021,9 +1018,16 @@ static void ext4_mb_choose_next_group_best_avail(struct ext4_allocation_context
*/
num_stripe_clusters = EXT4_NUM_B2C(sbi, sbi->s_stripe);
if (1 << min_order < num_stripe_clusters)
- min_order = fls(num_stripe_clusters);
+ /*
+ * We consider 1 order less because later we round
+ * up the goal len to num_stripe_clusters
+ */
+ min_order = fls(num_stripe_clusters) - 1;
}
+ if (1 << min_order < ac->ac_o_ex.fe_len)
+ min_order = fls(ac->ac_o_ex.fe_len);
+
for (i = order; i >= min_order; i--) {
int frag_order;
/*
The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 5d5460fa7932bed3a9082a6a8852cfbdb46acbe8
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023072404-hubcap-railroad-9c52@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
5d5460fa7932 ("ext4: fix off by one issue in ext4_mb_choose_next_group_best_avail()")
f52f3d2b9fba ("ext4: Give symbolic names to mballoc criterias")
7e170922f06b ("ext4: Add allocation criteria 1.5 (CR1_5)")
1b4200112108 ("ext4: Avoid scanning smaller extents in BG during CR1")
3ef5d2638796 ("ext4: Add counter to track successful allocation of goal length")
fdd9a00943a5 ("ext4: Add per CR extent scanned counter")
4eb7a4a1a33b ("ext4: Convert mballoc cr (criteria) to enum")
c3defd99d58c ("ext4: treat stripe in block unit")
361eb69fc99f ("ext4: Remove the logic to trim inode PAs")
3872778664e3 ("ext4: Use rbtrees to manage PAs instead of inode i_prealloc_list")
a8e38fd37cff ("ext4: Convert pa->pa_inode_list and pa->pa_obj_lock into a union")
93cdf49f6eca ("ext4: Fix best extent lstart adjustment logic in ext4_mb_new_inode_pa()")
0830344c953a ("ext4: Abstract out overlap fix/check logic in ext4_mb_normalize_request()")
7692094ac513 ("ext4: Move overlap assert logic into a separate function")
bcf434992145 ("ext4: Refactor code in ext4_mb_normalize_request() and ext4_mb_use_preallocated()")
e86a718228b6 ("ext4: Stop searching if PA doesn't satisfy non-extent file")
91a48aaf59d0 ("ext4: avoid unnecessary pointer dereference in ext4_mb_normalize_request")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 5d5460fa7932bed3a9082a6a8852cfbdb46acbe8 Mon Sep 17 00:00:00 2001
From: Ojaswin Mujoo <ojaswin(a)linux.ibm.com>
Date: Fri, 9 Jun 2023 16:04:03 +0530
Subject: [PATCH] ext4: fix off by one issue in
ext4_mb_choose_next_group_best_avail()
In ext4_mb_choose_next_group_best_avail(), we want the start order to be
1 less than goal length and the min_order to be, at max, 1 more than the
original length. This commit fixes an off by one issue that arose due to
the fact that 1 << fls(n) > (n).
After all the processing:
order = 1 order below goal len
min_order = maximum of the three:-
- order - trim_order
- 1 order below B2C(s_stripe)
- 1 order above original len
Cc: stable(a)kernel.org
Fixes: 33122aa930 ("ext4: Add allocation criteria 1.5 (CR1_5)")
Signed-off-by: Ojaswin Mujoo <ojaswin(a)linux.ibm.com>
Link: https://lore.kernel.org/r/20230609103403.112807-1-ojaswin@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso(a)mit.edu>
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index a2475b8c9fb5..456150ef6111 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -1006,14 +1006,11 @@ static void ext4_mb_choose_next_group_best_avail(struct ext4_allocation_context
* fls() instead since we need to know the actual length while modifying
* goal length.
*/
- order = fls(ac->ac_g_ex.fe_len);
+ order = fls(ac->ac_g_ex.fe_len) - 1;
min_order = order - sbi->s_mb_best_avail_max_trim_order;
if (min_order < 0)
min_order = 0;
- if (1 << min_order < ac->ac_o_ex.fe_len)
- min_order = fls(ac->ac_o_ex.fe_len) + 1;
-
if (sbi->s_stripe > 0) {
/*
* We are assuming that stripe size is always a multiple of
@@ -1021,9 +1018,16 @@ static void ext4_mb_choose_next_group_best_avail(struct ext4_allocation_context
*/
num_stripe_clusters = EXT4_NUM_B2C(sbi, sbi->s_stripe);
if (1 << min_order < num_stripe_clusters)
- min_order = fls(num_stripe_clusters);
+ /*
+ * We consider 1 order less because later we round
+ * up the goal len to num_stripe_clusters
+ */
+ min_order = fls(num_stripe_clusters) - 1;
}
+ if (1 << min_order < ac->ac_o_ex.fe_len)
+ min_order = fls(ac->ac_o_ex.fe_len);
+
for (i = order; i >= min_order; i--) {
int frag_order;
/*
The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.14.y
git checkout FETCH_HEAD
git cherry-pick -x c2d6fd9d6f35079f1669f0100f05b46708c74b7f
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023072459-unmolded-serrated-1862@gregkh' --subject-prefix 'PATCH 4.14.y' HEAD^..
Possible dependencies:
c2d6fd9d6f35 ("jbd2: recheck chechpointing non-dirty buffer")
4ba3fcdde7e3 ("jbd2,ext4: add a shrinker to release checkpointed buffers")
214eb5a4d8a2 ("jbd2: remove redundant buffer io error checks")
2bf31d94423c ("jbd2: fix kernel-doc markups")
60ed633f51d0 ("jbd2: fix incorrect code style")
ccd3c4373eac ("jbd2: fix use after free in jbd2_log_do_checkpoint()")
f69120ce6c02 ("jbd2: fix sphinx kernel-doc build warnings")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From c2d6fd9d6f35079f1669f0100f05b46708c74b7f Mon Sep 17 00:00:00 2001
From: Zhang Yi <yi.zhang(a)huawei.com>
Date: Tue, 6 Jun 2023 21:59:23 +0800
Subject: [PATCH] jbd2: recheck chechpointing non-dirty buffer
There is a long-standing metadata corruption issue that happens from
time to time, but it's very difficult to reproduce and analyse, benefit
from the JBD2_CYCLE_RECORD option, we found out that the problem is the
checkpointing process miss to write out some buffers which are raced by
another do_get_write_access(). Looks below for detail.
jbd2_log_do_checkpoint() //transaction X
//buffer A is dirty and not belones to any transaction
__buffer_relink_io() //move it to the IO list
__flush_batch()
write_dirty_buffer()
do_get_write_access()
clear_buffer_dirty
__jbd2_journal_file_buffer()
//add buffer A to a new transaction Y
lock_buffer(bh)
//doesn't write out
__jbd2_journal_remove_checkpoint()
//finish checkpoint except buffer A
//filesystem corrupt if the new transaction Y isn't fully write out.
Due to the t_checkpoint_list walking loop in jbd2_log_do_checkpoint()
have already handles waiting for buffers under IO and re-added new
transaction to complete commit, and it also removing cleaned buffers,
this makes sure the list will eventually get empty. So it's fine to
leave buffers on the t_checkpoint_list while flushing out and completely
stop using the t_checkpoint_io_list.
Cc: stable(a)vger.kernel.org
Suggested-by: Jan Kara <jack(a)suse.cz>
Signed-off-by: Zhang Yi <yi.zhang(a)huawei.com>
Tested-by: Zhihao Cheng <chengzhihao1(a)huawei.com>
Reviewed-by: Jan Kara <jack(a)suse.cz>
Link: https://lore.kernel.org/r/20230606135928.434610-2-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso(a)mit.edu>
diff --git a/fs/jbd2/checkpoint.c b/fs/jbd2/checkpoint.c
index 51bd38da21cd..25e3c20eb19f 100644
--- a/fs/jbd2/checkpoint.c
+++ b/fs/jbd2/checkpoint.c
@@ -57,28 +57,6 @@ static inline void __buffer_unlink(struct journal_head *jh)
}
}
-/*
- * Move a buffer from the checkpoint list to the checkpoint io list
- *
- * Called with j_list_lock held
- */
-static inline void __buffer_relink_io(struct journal_head *jh)
-{
- transaction_t *transaction = jh->b_cp_transaction;
-
- __buffer_unlink_first(jh);
-
- if (!transaction->t_checkpoint_io_list) {
- jh->b_cpnext = jh->b_cpprev = jh;
- } else {
- jh->b_cpnext = transaction->t_checkpoint_io_list;
- jh->b_cpprev = transaction->t_checkpoint_io_list->b_cpprev;
- jh->b_cpprev->b_cpnext = jh;
- jh->b_cpnext->b_cpprev = jh;
- }
- transaction->t_checkpoint_io_list = jh;
-}
-
/*
* Check a checkpoint buffer could be release or not.
*
@@ -183,6 +161,7 @@ __flush_batch(journal_t *journal, int *batch_count)
struct buffer_head *bh = journal->j_chkpt_bhs[i];
BUFFER_TRACE(bh, "brelse");
__brelse(bh);
+ journal->j_chkpt_bhs[i] = NULL;
}
*batch_count = 0;
}
@@ -242,6 +221,11 @@ int jbd2_log_do_checkpoint(journal_t *journal)
jh = transaction->t_checkpoint_list;
bh = jh2bh(jh);
+ /*
+ * The buffer may be writing back, or flushing out in the
+ * last couple of cycles, or re-adding into a new transaction,
+ * need to check it again until it's unlocked.
+ */
if (buffer_locked(bh)) {
get_bh(bh);
spin_unlock(&journal->j_list_lock);
@@ -287,28 +271,32 @@ int jbd2_log_do_checkpoint(journal_t *journal)
}
if (!buffer_dirty(bh)) {
BUFFER_TRACE(bh, "remove from checkpoint");
- if (__jbd2_journal_remove_checkpoint(jh))
- /* The transaction was released; we're done */
+ /*
+ * If the transaction was released or the checkpoint
+ * list was empty, we're done.
+ */
+ if (__jbd2_journal_remove_checkpoint(jh) ||
+ !transaction->t_checkpoint_list)
goto out;
- continue;
+ } else {
+ /*
+ * We are about to write the buffer, it could be
+ * raced by some other transaction shrink or buffer
+ * re-log logic once we release the j_list_lock,
+ * leave it on the checkpoint list and check status
+ * again to make sure it's clean.
+ */
+ BUFFER_TRACE(bh, "queue");
+ get_bh(bh);
+ J_ASSERT_BH(bh, !buffer_jwrite(bh));
+ journal->j_chkpt_bhs[batch_count++] = bh;
+ transaction->t_chp_stats.cs_written++;
+ transaction->t_checkpoint_list = jh->b_cpnext;
}
- /*
- * Important: we are about to write the buffer, and
- * possibly block, while still holding the journal
- * lock. We cannot afford to let the transaction
- * logic start messing around with this buffer before
- * we write it to disk, as that would break
- * recoverability.
- */
- BUFFER_TRACE(bh, "queue");
- get_bh(bh);
- J_ASSERT_BH(bh, !buffer_jwrite(bh));
- journal->j_chkpt_bhs[batch_count++] = bh;
- __buffer_relink_io(jh);
- transaction->t_chp_stats.cs_written++;
+
if ((batch_count == JBD2_NR_BATCH) ||
- need_resched() ||
- spin_needbreak(&journal->j_list_lock))
+ need_resched() || spin_needbreak(&journal->j_list_lock) ||
+ jh2bh(transaction->t_checkpoint_list) == journal->j_chkpt_bhs[0])
goto unlock_and_flush;
}
@@ -322,38 +310,6 @@ int jbd2_log_do_checkpoint(journal_t *journal)
goto restart;
}
- /*
- * Now we issued all of the transaction's buffers, let's deal
- * with the buffers that are out for I/O.
- */
-restart2:
- /* Did somebody clean up the transaction in the meanwhile? */
- if (journal->j_checkpoint_transactions != transaction ||
- transaction->t_tid != this_tid)
- goto out;
-
- while (transaction->t_checkpoint_io_list) {
- jh = transaction->t_checkpoint_io_list;
- bh = jh2bh(jh);
- if (buffer_locked(bh)) {
- get_bh(bh);
- spin_unlock(&journal->j_list_lock);
- wait_on_buffer(bh);
- /* the journal_head may have gone by now */
- BUFFER_TRACE(bh, "brelse");
- __brelse(bh);
- spin_lock(&journal->j_list_lock);
- goto restart2;
- }
-
- /*
- * Now in whatever state the buffer currently is, we
- * know that it has been written out and so we can
- * drop it from the list
- */
- if (__jbd2_journal_remove_checkpoint(jh))
- break;
- }
out:
spin_unlock(&journal->j_list_lock);
result = jbd2_cleanup_journal_tail(journal);
The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.19.y
git checkout FETCH_HEAD
git cherry-pick -x c2d6fd9d6f35079f1669f0100f05b46708c74b7f
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023072457-patio-doornail-5f44@gregkh' --subject-prefix 'PATCH 4.19.y' HEAD^..
Possible dependencies:
c2d6fd9d6f35 ("jbd2: recheck chechpointing non-dirty buffer")
4ba3fcdde7e3 ("jbd2,ext4: add a shrinker to release checkpointed buffers")
214eb5a4d8a2 ("jbd2: remove redundant buffer io error checks")
2bf31d94423c ("jbd2: fix kernel-doc markups")
60ed633f51d0 ("jbd2: fix incorrect code style")
ccd3c4373eac ("jbd2: fix use after free in jbd2_log_do_checkpoint()")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From c2d6fd9d6f35079f1669f0100f05b46708c74b7f Mon Sep 17 00:00:00 2001
From: Zhang Yi <yi.zhang(a)huawei.com>
Date: Tue, 6 Jun 2023 21:59:23 +0800
Subject: [PATCH] jbd2: recheck chechpointing non-dirty buffer
There is a long-standing metadata corruption issue that happens from
time to time, but it's very difficult to reproduce and analyse, benefit
from the JBD2_CYCLE_RECORD option, we found out that the problem is the
checkpointing process miss to write out some buffers which are raced by
another do_get_write_access(). Looks below for detail.
jbd2_log_do_checkpoint() //transaction X
//buffer A is dirty and not belones to any transaction
__buffer_relink_io() //move it to the IO list
__flush_batch()
write_dirty_buffer()
do_get_write_access()
clear_buffer_dirty
__jbd2_journal_file_buffer()
//add buffer A to a new transaction Y
lock_buffer(bh)
//doesn't write out
__jbd2_journal_remove_checkpoint()
//finish checkpoint except buffer A
//filesystem corrupt if the new transaction Y isn't fully write out.
Due to the t_checkpoint_list walking loop in jbd2_log_do_checkpoint()
have already handles waiting for buffers under IO and re-added new
transaction to complete commit, and it also removing cleaned buffers,
this makes sure the list will eventually get empty. So it's fine to
leave buffers on the t_checkpoint_list while flushing out and completely
stop using the t_checkpoint_io_list.
Cc: stable(a)vger.kernel.org
Suggested-by: Jan Kara <jack(a)suse.cz>
Signed-off-by: Zhang Yi <yi.zhang(a)huawei.com>
Tested-by: Zhihao Cheng <chengzhihao1(a)huawei.com>
Reviewed-by: Jan Kara <jack(a)suse.cz>
Link: https://lore.kernel.org/r/20230606135928.434610-2-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso(a)mit.edu>
diff --git a/fs/jbd2/checkpoint.c b/fs/jbd2/checkpoint.c
index 51bd38da21cd..25e3c20eb19f 100644
--- a/fs/jbd2/checkpoint.c
+++ b/fs/jbd2/checkpoint.c
@@ -57,28 +57,6 @@ static inline void __buffer_unlink(struct journal_head *jh)
}
}
-/*
- * Move a buffer from the checkpoint list to the checkpoint io list
- *
- * Called with j_list_lock held
- */
-static inline void __buffer_relink_io(struct journal_head *jh)
-{
- transaction_t *transaction = jh->b_cp_transaction;
-
- __buffer_unlink_first(jh);
-
- if (!transaction->t_checkpoint_io_list) {
- jh->b_cpnext = jh->b_cpprev = jh;
- } else {
- jh->b_cpnext = transaction->t_checkpoint_io_list;
- jh->b_cpprev = transaction->t_checkpoint_io_list->b_cpprev;
- jh->b_cpprev->b_cpnext = jh;
- jh->b_cpnext->b_cpprev = jh;
- }
- transaction->t_checkpoint_io_list = jh;
-}
-
/*
* Check a checkpoint buffer could be release or not.
*
@@ -183,6 +161,7 @@ __flush_batch(journal_t *journal, int *batch_count)
struct buffer_head *bh = journal->j_chkpt_bhs[i];
BUFFER_TRACE(bh, "brelse");
__brelse(bh);
+ journal->j_chkpt_bhs[i] = NULL;
}
*batch_count = 0;
}
@@ -242,6 +221,11 @@ int jbd2_log_do_checkpoint(journal_t *journal)
jh = transaction->t_checkpoint_list;
bh = jh2bh(jh);
+ /*
+ * The buffer may be writing back, or flushing out in the
+ * last couple of cycles, or re-adding into a new transaction,
+ * need to check it again until it's unlocked.
+ */
if (buffer_locked(bh)) {
get_bh(bh);
spin_unlock(&journal->j_list_lock);
@@ -287,28 +271,32 @@ int jbd2_log_do_checkpoint(journal_t *journal)
}
if (!buffer_dirty(bh)) {
BUFFER_TRACE(bh, "remove from checkpoint");
- if (__jbd2_journal_remove_checkpoint(jh))
- /* The transaction was released; we're done */
+ /*
+ * If the transaction was released or the checkpoint
+ * list was empty, we're done.
+ */
+ if (__jbd2_journal_remove_checkpoint(jh) ||
+ !transaction->t_checkpoint_list)
goto out;
- continue;
+ } else {
+ /*
+ * We are about to write the buffer, it could be
+ * raced by some other transaction shrink or buffer
+ * re-log logic once we release the j_list_lock,
+ * leave it on the checkpoint list and check status
+ * again to make sure it's clean.
+ */
+ BUFFER_TRACE(bh, "queue");
+ get_bh(bh);
+ J_ASSERT_BH(bh, !buffer_jwrite(bh));
+ journal->j_chkpt_bhs[batch_count++] = bh;
+ transaction->t_chp_stats.cs_written++;
+ transaction->t_checkpoint_list = jh->b_cpnext;
}
- /*
- * Important: we are about to write the buffer, and
- * possibly block, while still holding the journal
- * lock. We cannot afford to let the transaction
- * logic start messing around with this buffer before
- * we write it to disk, as that would break
- * recoverability.
- */
- BUFFER_TRACE(bh, "queue");
- get_bh(bh);
- J_ASSERT_BH(bh, !buffer_jwrite(bh));
- journal->j_chkpt_bhs[batch_count++] = bh;
- __buffer_relink_io(jh);
- transaction->t_chp_stats.cs_written++;
+
if ((batch_count == JBD2_NR_BATCH) ||
- need_resched() ||
- spin_needbreak(&journal->j_list_lock))
+ need_resched() || spin_needbreak(&journal->j_list_lock) ||
+ jh2bh(transaction->t_checkpoint_list) == journal->j_chkpt_bhs[0])
goto unlock_and_flush;
}
@@ -322,38 +310,6 @@ int jbd2_log_do_checkpoint(journal_t *journal)
goto restart;
}
- /*
- * Now we issued all of the transaction's buffers, let's deal
- * with the buffers that are out for I/O.
- */
-restart2:
- /* Did somebody clean up the transaction in the meanwhile? */
- if (journal->j_checkpoint_transactions != transaction ||
- transaction->t_tid != this_tid)
- goto out;
-
- while (transaction->t_checkpoint_io_list) {
- jh = transaction->t_checkpoint_io_list;
- bh = jh2bh(jh);
- if (buffer_locked(bh)) {
- get_bh(bh);
- spin_unlock(&journal->j_list_lock);
- wait_on_buffer(bh);
- /* the journal_head may have gone by now */
- BUFFER_TRACE(bh, "brelse");
- __brelse(bh);
- spin_lock(&journal->j_list_lock);
- goto restart2;
- }
-
- /*
- * Now in whatever state the buffer currently is, we
- * know that it has been written out and so we can
- * drop it from the list
- */
- if (__jbd2_journal_remove_checkpoint(jh))
- break;
- }
out:
spin_unlock(&journal->j_list_lock);
result = jbd2_cleanup_journal_tail(journal);