[PATCH AUTOSEL 6.18-6.1] gfs2: Fix use of bio_chain

[PATCH AUTOSEL 6.18-6.1] gfs2: Fix use of bio_chain

[Sasha Levin]

From: Andreas Gruenbacher <agruenba@redhat.com>

[ Upstream commit 8a157e0a0aa5143b5d94201508c0ca1bb8cfb941 ]

In gfs2_chain_bio(), the call to bio_chain() has its arguments swapped.
The result is leaked bios and incorrect synchronization (only the last
bio will actually be waited for).  This code is only used during mount
and filesystem thaw, so the bug normally won't be noticeable.

Reported-by: Stephen Zhang <starzhangzsd@gmail.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

LLM Generated explanations, may be completely bogus:



 fs/gfs2/lops.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/gfs2/lops.c b/fs/gfs2/lops.c
index 9c8c305a75c46..914d03f6c4e82 100644
--- a/fs/gfs2/lops.c
+++ b/fs/gfs2/lops.c
@@ -487,7 +487,7 @@ static struct bio *gfs2_chain_bio(struct bio *prev, unsigned int nr_iovecs)
 	new = bio_alloc(prev->bi_bdev, nr_iovecs, prev->bi_opf, GFP_NOIO);
 	bio_clone_blkg_association(new, prev);
 	new->bi_iter.bi_sector = bio_end_sector(prev);
-	bio_chain(new, prev);
+	bio_chain(prev, new);
 	submit_bio(prev);
 	return new;
 }
-- 
2.51.0

[PATCH AUTOSEL 6.18-6.6] gfs2: fix remote evict for read-only filesystems

[Sasha Levin]

From: Andreas Gruenbacher <agruenba@redhat.com>

[ Upstream commit 64c10ed9274bc46416f502afea48b4ae11279669 ]

When a node tries to delete an inode, it first requests exclusive access
to the iopen glock.  This triggers demote requests on all remote nodes
currently holding the iopen glock.  To satisfy those requests, the
remote nodes evict the inode in question, or they poke the corresponding
inode glock to signal that the inode is still in active use.

This behavior doesn't depend on whether or not a filesystem is
read-only, so remove the incorrect read-only check.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

LLM Generated explanations, may be completely bogus:



 fs/gfs2/glops.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c
index 0c0a80b3bacab..0c68ab4432b08 100644
--- a/fs/gfs2/glops.c
+++ b/fs/gfs2/glops.c
@@ -630,8 +630,7 @@ static void iopen_go_callback(struct gfs2_glock *gl, bool remote)
 	struct gfs2_inode *ip = gl->gl_object;
 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
 
-	if (!remote || sb_rdonly(sdp->sd_vfs) ||
-	    test_bit(SDF_KILL, &sdp->sd_flags))
+	if (!remote || test_bit(SDF_KILL, &sdp->sd_flags))
 		return;
 
 	if (gl->gl_demote_state == LM_ST_UNLOCKED &&
-- 
2.51.0

[PATCH AUTOSEL 6.18-6.12] gfs2: Fix "gfs2: Switch to wait_event in gfs2_quotad"

[Sasha Levin]

From: Andreas Gruenbacher <agruenba@redhat.com>

[ Upstream commit dff1fb6d8b7abe5b1119fa060f5d6b3370bf10ac ]

Commit e4a8b5481c59a ("gfs2: Switch to wait_event in gfs2_quotad") broke
cyclic statfs syncing, so the numbers reported by "df" could easily get
completely out of sync with reality.  Fix this by reverting part of
commit e4a8b5481c59a for now.

A follow-up commit will clean this code up later.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

LLM Generated explanations, may be completely bogus:



 fs/gfs2/quota.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c
index 2298e06797ac3..f2df01f801b81 100644
--- a/fs/gfs2/quota.c
+++ b/fs/gfs2/quota.c
@@ -1616,7 +1616,7 @@ int gfs2_quotad(void *data)
 
 		t = min(quotad_timeo, statfs_timeo);
 
-		t = wait_event_freezable_timeout(sdp->sd_quota_wait,
+		t -= wait_event_freezable_timeout(sdp->sd_quota_wait,
 				sdp->sd_statfs_force_sync ||
 				gfs2_withdrawing_or_withdrawn(sdp) ||
 				kthread_should_stop(),
-- 
2.51.0

[PATCH AUTOSEL 6.18-6.12] gfs2: Fix "gfs2: Switch to wait_event in gfs2_quotad"

[Sasha Levin]

From: Andreas Gruenbacher <agruenba@redhat.com>

[ Upstream commit dff1fb6d8b7abe5b1119fa060f5d6b3370bf10ac ]

Commit e4a8b5481c59a ("gfs2: Switch to wait_event in gfs2_quotad") broke
cyclic statfs syncing, so the numbers reported by "df" could easily get
completely out of sync with reality.  Fix this by reverting part of
commit e4a8b5481c59a for now.

A follow-up commit will clean this code up later.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

LLM Generated explanations, may be completely bogus:

### 7. STABILITY INDICATORS

- **Author**: Andreas Gruenbacher (GFS2 maintainer) - same person who
  introduced the bug
- **Fix type**: Partial revert - restores known-working behavior
- **Commit message**: Clear acknowledgment of the problem and solution
- **Testing**: Maintainer would have verified the fix given the severity

### Summary Assessment

| Criteria | Assessment |
|----------|------------|
| Fixes real bug | ✅ Yes - broken statfs sync breaks "df" reporting |
| Obviously correct | ✅ Yes - single character change restoring original
logic |
| Small and contained | ✅ Yes - 1 character change in 1 file |
| No new features | ✅ Yes - pure regression fix |
| User impact | HIGH - affects all GFS2 users |
| Risk | VERY LOW - restores proven behavior |
| Dependencies | Needs commit e4a8b5481c59a (in 6.6+) |

### Conclusion

This commit is an excellent candidate for stable backport:

1. **Fixes a real, user-visible bug**: Disk usage reporting being
   "completely out of sync with reality" is a serious issue for any
   filesystem.

2. **Minimal, surgical fix**: A single character change (`=` → `-=`)
   with zero risk of collateral damage.

3. **Restores original behavior**: This is a partial revert, returning
   to the proven timing logic that worked before the buggy conversion.

4. **Critical subsystem**: GFS2 is a clustered filesystem used in
   enterprise environments where correct disk space reporting is
   essential.

5. **Clear provenance**: Written by the GFS2 maintainer who introduced
   the original bug, so he understands exactly what went wrong.

The only consideration is that this fix requires the buggy commit
e4a8b5481c59a to be present (v6.6+). For stable trees 6.6.y and later,
this fix should be backported.

**YES**

 fs/gfs2/quota.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c
index 2298e06797ac3..f2df01f801b81 100644
--- a/fs/gfs2/quota.c
+++ b/fs/gfs2/quota.c
@@ -1616,7 +1616,7 @@ int gfs2_quotad(void *data)
 
 		t = min(quotad_timeo, statfs_timeo);
 
-		t = wait_event_freezable_timeout(sdp->sd_quota_wait,
+		t -= wait_event_freezable_timeout(sdp->sd_quota_wait,
 				sdp->sd_statfs_force_sync ||
 				gfs2_withdrawing_or_withdrawn(sdp) ||
 				kthread_should_stop(),
-- 
2.51.0