Patch "xfs: error out when a superblock buffer update reduces the agcount" has been added to the 6.6-stable tree

This is a note to let you know that I've just added the patch titled

    xfs: error out when a superblock buffer update reduces the agcount

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:
     xfs-error-out-when-a-superblock-buffer-update-reduces-the-agcount.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 <[email protected]> know about it.


From [email protected] Wed Feb  5 22:41:18 2025
From: Catherine Hoang <[email protected]>
Date: Wed,  5 Feb 2025 13:40:20 -0800
Subject: xfs: error out when a superblock buffer update reduces the agcount
To: [email protected]
Cc: [email protected]
Message-ID: <[email protected]>

From: Christoph Hellwig <[email protected]>

commit b882b0f8138ffa935834e775953f1630f89bbb62 upstream.

XFS currently does not support reducing the agcount, so error out if
a logged sb buffer tries to shrink the agcount.

Signed-off-by: Christoph Hellwig <[email protected]>
Reviewed-by: Brian Foster <[email protected]>
Reviewed-by: Darrick J. Wong <[email protected]>
Signed-off-by: Carlos Maiolino <[email protected]>
Signed-off-by: Catherine Hoang <[email protected]>
Acked-by: Darrick J. Wong <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
 fs/xfs/xfs_buf_item_recover.c |    5 +++++
 1 file changed, 5 insertions(+)

--- a/fs/xfs/xfs_buf_item_recover.c
+++ b/fs/xfs/xfs_buf_item_recover.c
@@ -713,6 +713,11 @@ xlog_recover_do_primary_sb_buffer(
 	 */
 	xfs_sb_from_disk(&mp->m_sb, dsb);
 
+	if (mp->m_sb.sb_agcount < orig_agcount) {
+		xfs_alert(mp, "Shrinking AG count in log recovery not supported");
+		return -EFSCORRUPTED;
+	}
+
 	/*
 	 * Initialize the new perags, and also update various block and inode
 	 * allocator setting based off the number of AGs or total blocks.


Patches currently in stable-queue which might be from [email protected] are

queue-6.6/xfs-return-bool-from-xfs_attr3_leaf_add.patch
queue-6.6/xfs-fix-a-sloppy-memory-handling-bug-in-xfs_iroot_realloc.patch
queue-6.6/xfs-streamline-xfs_filestream_pick_ag.patch
queue-6.6/xfs-merge-xfs_attr_leaf_try_add-into-xfs_attr_leaf_addname.patch
queue-6.6/xfs-don-t-free-cowblocks-from-under-dirty-pagecache-on-unshare.patch
queue-6.6/xfs-pass-the-exact-range-to-initialize-to-xfs_initialize_perag.patch
queue-6.6/xfs-assert-a-valid-limit-in-xfs_rtfind_forw.patch
queue-6.6/xfs-don-t-use-__gfp_retry_mayfail-in-xfs_initialize_perag.patch
queue-6.6/xfs-use-try_cmpxchg-in-xlog_cil_insert_pcp_aggregate.patch
queue-6.6/xfs-don-t-ifdef-around-the-exact-minlen-allocations.patch
queue-6.6/xfs-reduce-unnecessary-searches-when-searching-for-the-best-extents.patch
queue-6.6/xfs-validate-inumber-in-xfs_iget.patch
queue-6.6/xfs-support-lowmode-allocations-in-xfs_bmap_exact_minlen_extent_alloc.patch
queue-6.6/xfs-skip-background-cowblock-trims-on-inodes-open-for-write.patch
queue-6.6/xfs-remove-empty-declartion-in-header-file.patch
queue-6.6/xfs-fold-xfs_bmap_alloc_userdata-into-xfs_bmapi_allocate.patch
queue-6.6/xfs-update-the-file-system-geometry-after-recoverying-superblock-buffers.patch
queue-6.6/xfs-call-xfs_bmap_exact_minlen_extent_alloc-from-xfs_bmap_btalloc.patch
queue-6.6/xfs-distinguish-extra-split-from-real-enospc-from-xfs_attr_node_try_addname.patch
queue-6.6/xfs-error-out-when-a-superblock-buffer-update-reduces-the-agcount.patch
queue-6.6/xfs-update-the-pag-for-the-last-ag-at-recovery-time.patch
queue-6.6/xfs-check-for-delayed-allocations-before-setting-extsize.patch
queue-6.6/xfs-fix-a-typo.patch
queue-6.6/xfs-distinguish-extra-split-from-real-enospc-from-xfs_attr3_leaf_split.patch