3 files changed, 69 insertions, 17 deletions

diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c
index 7839efe050bf..000cc7f4a3ce 100644
--- a/fs/xfs/libxfs/xfs_alloc.c
+++ b/fs/xfs/libxfs/xfs_alloc.c
@@ -3444,16 +3444,41 @@ xfs_alloc_read_agf(
 
 		set_bit(XFS_AGSTATE_AGF_INIT, &pag->pag_opstate);
 	}
+
 #ifdef DEBUG
-	else if (!xfs_is_shutdown(mp)) {
-		ASSERT(pag->pagf_freeblks == be32_to_cpu(agf->agf_freeblks));
-		ASSERT(pag->pagf_btreeblks == be32_to_cpu(agf->agf_btreeblks));
-		ASSERT(pag->pagf_flcount == be32_to_cpu(agf->agf_flcount));
-		ASSERT(pag->pagf_longest == be32_to_cpu(agf->agf_longest));
-		ASSERT(pag->pagf_bno_level == be32_to_cpu(agf->agf_bno_level));
-		ASSERT(pag->pagf_cnt_level == be32_to_cpu(agf->agf_cnt_level));
+	/*
+	 * It's possible for the AGF to be out of sync if the block device is
+	 * silently dropping writes. This can happen in fstests with dmflakey
+	 * enabled, which allows the buffer to be cleaned and reclaimed by
+	 * memory pressure and then re-read from disk here. We will get a
+	 * stale version of the AGF from disk, and nothing good can happen from
+	 * here. Hence if we detect this situation, immediately shut down the
+	 * filesystem.
+	 *
+	 * This can also happen if we are already in the middle of a forced
+	 * shutdown, so don't bother checking if we are already shut down.
+	 */
+	if (!xfs_is_shutdown(pag_mount(pag))) {
+		bool	ok = true;
+
+		ok &= pag->pagf_freeblks == be32_to_cpu(agf->agf_freeblks);
+		ok &= pag->pagf_freeblks == be32_to_cpu(agf->agf_freeblks);
+		ok &= pag->pagf_btreeblks == be32_to_cpu(agf->agf_btreeblks);
+		ok &= pag->pagf_flcount == be32_to_cpu(agf->agf_flcount);
+		ok &= pag->pagf_longest == be32_to_cpu(agf->agf_longest);
+		ok &= pag->pagf_bno_level == be32_to_cpu(agf->agf_bno_level);
+		ok &= pag->pagf_cnt_level == be32_to_cpu(agf->agf_cnt_level);
+
+		if (XFS_IS_CORRUPT(pag_mount(pag), !ok)) {
+			xfs_ag_mark_sick(pag, XFS_SICK_AG_AGF);
+			xfs_trans_brelse(tp, agfbp);
+			xfs_force_shutdown(pag_mount(pag),
+					SHUTDOWN_CORRUPT_ONDISK);
+			return -EFSCORRUPTED;
+		}
 	}
-#endif
+#endif /* DEBUG */
+
 	if (agfbpp)
 		*agfbpp = agfbp;
 	else
diff --git a/fs/xfs/libxfs/xfs_group.c b/fs/xfs/libxfs/xfs_group.c
index e9d76bcdc820..20ad7c309489 100644
--- a/fs/xfs/libxfs/xfs_group.c
+++ b/fs/xfs/libxfs/xfs_group.c
@@ -163,7 +163,8 @@ xfs_group_free(
 
 	xfs_defer_drain_free(&xg->xg_intents_drain);
 #ifdef __KERNEL__
-	kfree(xg->xg_busy_extents);
+	if (xfs_group_has_extent_busy(xg->xg_mount, xg->xg_type))
+		kfree(xg->xg_busy_extents);
 #endif
 
 	if (uninit)
@@ -189,9 +190,11 @@ xfs_group_insert(
 	xg->xg_type = type;
 
 #ifdef __KERNEL__
-	xg->xg_busy_extents = xfs_extent_busy_alloc();
-	if (!xg->xg_busy_extents)
-		return -ENOMEM;
+	if (xfs_group_has_extent_busy(mp, type)) {
+		xg->xg_busy_extents = xfs_extent_busy_alloc();
+		if (!xg->xg_busy_extents)
+			return -ENOMEM;
+	}
 	spin_lock_init(&xg->xg_state_lock);
 	xfs_hooks_init(&xg->xg_rmap_update_hooks);
 #endif
@@ -210,7 +213,8 @@ xfs_group_insert(
 out_drain:
 	xfs_defer_drain_free(&xg->xg_intents_drain);
 #ifdef __KERNEL__
-	kfree(xg->xg_busy_extents);
+	if (xfs_group_has_extent_busy(xg->xg_mount, xg->xg_type))
+		kfree(xg->xg_busy_extents);
 #endif
 	return error;
 }
diff --git a/fs/xfs/libxfs/xfs_ialloc.c b/fs/xfs/libxfs/xfs_ialloc.c
index 0c47b5c6ca7d..750111634d9f 100644
--- a/fs/xfs/libxfs/xfs_ialloc.c
+++ b/fs/xfs/libxfs/xfs_ialloc.c
@@ -2801,12 +2801,35 @@ xfs_ialloc_read_agi(
 		set_bit(XFS_AGSTATE_AGI_INIT, &pag->pag_opstate);
 	}
 
+#ifdef DEBUG
 	/*
-	 * It's possible for these to be out of sync if
-	 * we are in the middle of a forced shutdown.
+	 * It's possible for the AGF to be out of sync if the block device is
+	 * silently dropping writes. This can happen in fstests with dmflakey
+	 * enabled, which allows the buffer to be cleaned and reclaimed by
+	 * memory pressure and then re-read from disk here. We will get a
+	 * stale version of the AGF from disk, and nothing good can happen from
+	 * here. Hence if we detect this situation, immediately shut down the
+	 * filesystem.
+	 *
+	 * This can also happen if we are already in the middle of a forced
+	 * shutdown, so don't bother checking if we are already shut down.
 	 */
-	ASSERT(pag->pagi_freecount == be32_to_cpu(agi->agi_freecount) ||
-		xfs_is_shutdown(pag_mount(pag)));
+	if (!xfs_is_shutdown(pag_mount(pag))) {
+		bool	ok = true;
+
+		ok &= pag->pagi_freecount == be32_to_cpu(agi->agi_freecount);
+		ok &= pag->pagi_count == be32_to_cpu(agi->agi_count);
+
+		if (XFS_IS_CORRUPT(pag_mount(pag), !ok)) {
+			xfs_ag_mark_sick(pag, XFS_SICK_AG_AGI);
+			xfs_trans_brelse(tp, agibp);
+			xfs_force_shutdown(pag_mount(pag),
+					SHUTDOWN_CORRUPT_ONDISK);
+			return -EFSCORRUPTED;
+		}
+	}
+#endif /* DEBUG */
+
 	if (agibpp)
 		*agibpp = agibp;
 	else