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Hallyn" , "Darrick J. Wong" , Christian Brauner , Josef Bacik , Jeff Layton , linux-kernel@vger.kernel.org, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, kernel-team@cloudflare.com In-Reply-To: References: <20260130-xfs-ima-fixup-v5-0-57e84ea91712@cloudflare.com> <20260130-xfs-ima-fixup-v5-3-57e84ea91712@cloudflare.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Date: Wed, 04 Feb 2026 23:26:27 -0500 Precedence: bulk X-Mailing-List: linux-integrity@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Evolution 3.56.2 (3.56.2-2.fc42) X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: isB5NKNz9U_iFU1lLWLg7WY9YxRtM4db X-Authority-Analysis: v=2.4 cv=VcX6/Vp9 c=1 sm=1 tr=0 ts=69841bf8 cx=c_pps a=3Bg1Hr4SwmMryq2xdFQyZA==:117 a=3Bg1Hr4SwmMryq2xdFQyZA==:17 a=IkcTkHD0fZMA:10 a=HzLeVaNsDn8A:10 a=VkNPw1HP01LnGYTKEx00:22 a=RobKdUFHg6JuvS5dcHMA:9 a=QEXdDO2ut3YA:10 X-Proofpoint-GUID: ZnH4SyeQhBDME7XvwUD8PyCjWpuOZnnL X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwMjA1MDAyNyBTYWx0ZWRfXzo6jxa4pO7Vu JIchXLuNAFTu1HXj9YCRR58m0H3qWnmshmHdBYp9Ov1BhGoAxG0ygNIBse54jGGxVb28ikGEPeO tzWbbovSIUvJ7Tq+nVusS/HDoMGWDlOVnFkHZwBeNz3bEwk3nmWYEFdAREwSEHqpaONdQAdWZQU BR0wKuyOjf2BQVtrDob2vU2mIO1DfU8hMctVZHR6jw+3vake0edezrsHRAI4ReWa8o0Ilx6oFla qxPZZ1Kdfwsji3k5pWEYhhFtnZ1SGxUwEEBHjk8MJfoFI5gXUsvVjRRkb7aE8Yk8g0JTDJU4k8A A/06ndAb7JfFeu6t+VNwYGQlAHJNkJtUR84z3zynm0CBE3V6FABsY0BtoOyTUvD+qNaFBizWI0v 3gYW6R2ZyKzNd8TT82a8jQt4mYIChyItPbu4Oe5FvTlIi9ONDbNFn4y06jqv+nZ5jD7KTcZmopZ MZ3UqHe6R0IqiS7aBjw== X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1121,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-02-04_08,2026-02-04_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 spamscore=0 adultscore=0 bulkscore=0 phishscore=0 lowpriorityscore=0 impostorscore=0 clxscore=1015 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2601150000 definitions=main-2602050027 On Wed, 2026-02-04 at 15:22 -0600, Frederick Lawler wrote: > That said, I think Mimi pointed out in an email [2] where multi-grain > file systems are impacted regardless of stacked fs or not due to the last > writer check. >=20 > I don't recall coming across that in my tests, but perhaps I did that > specific test wrong? To be sure, I created the C program, and on the VM, > created a XFS disk, mounted it on loopback, ran the rdwr program on > "somefile" multiple times, and only got 1 audit log for it, until I > mutated it with touch, and only got 2 hits: original + after mutation > after running the program multiple times.=20 >=20 > I'm not sure what's going on there, so I'll look into that a bit more, > but so far the impact is stacked file systems & multigrain ctime AFAIK. Make sure you're testing without your patch set applied or at least the las= t patch. Mimi