linux-kernel - [PATCH] ext4/060: Skip for dax devices on non-4k page sizes

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Message-ID: <20251011134708.2426769-1-ojaswin@linux.ibm.com>
Date: Sat, 11 Oct 2025 19:17:08 +0530
From: Ojaswin Mujoo <ojaswin@...ux.ibm.com>
To: Zorro Lang <zlang@...hat.com>, fstests@...r.kernel.org
Cc: srivathsa.d.dara@...cle.com, linux-kernel@...r.kernel.org,
        Disha Goel <disgoel@...ux.ibm.com>
Subject: [PATCH] ext4/060: Skip for dax devices on non-4k page sizes

This test tries to trigger an ext4 corruption by resizing past the
meta_bg size (8GB on 4k blocksize) in ext4. Since the test is sensistive
to the size and FS layout it hardcodes the 4kb blocksize ignoring user's
$MKFS_OPTIONS. While this is okay for most cases it fails for dax based
filesystems where system pagesize is non-4k.

One way to work past this is to make the test blocksize agnostic, but
since we still need the disk to be as big as the meta_bg size, this
means for blocksize=64kb filesystems we need a scratch disk of ~4TB
which is not feasible.

Hence, just skip the test if fsdax is used in a non-4k page size system.

Reported-by: Disha Goel <disgoel@...ux.ibm.com>
Signed-off-by: Ojaswin Mujoo <ojaswin@...ux.ibm.com>
---
 tests/ext4/060 | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tests/ext4/060 b/tests/ext4/060
index b8cc542f..565f8601 100755
--- a/tests/ext4/060
+++ b/tests/ext4/060
@@ -17,6 +17,10 @@ _begin_fstest auto resize quick
 _exclude_fs ext2
 _exclude_fs ext3

+if __scratch_uses_fsdax && [[ $(_get_page_size) -ne 4096 ]]; then
+    _notrun "Test does not support dax on non-4k pagesize systems"
+fi
+
 _fixed_by_kernel_commit a6b3bfe176e8 \
 	"ext4: fix corruption during on-line resize"

-- 
2.49.0