On Fri, 15 Nov 2024, Andrew Morton wrote:

The patch titled Subject: mm: revert "mm: shmem: fix data-race in shmem_getattr()" has been added to the -mm mm-hotfixes-unstable branch. Its filename is mm-revert-mm-shmem-fix-data-race-in-shmem_getattr.patch

This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...

This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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From: Andrew Morton akpm@linux-foundation.org Subject: mm: revert "mm: shmem: fix data-race in shmem_getattr()" Date: Fri Nov 15 04:57:24 PM PST 2024

Revert d949d1d14fa2 ("mm: shmem: fix data-race in shmem_getattr()") as suggested by Chuck [1]. It is causing deadlocks when accessing tmpfs over NFS.

Link: https://lkml.kernel.org/r/ZzdxKF39VEmXSSyN@tissot.1015granger.net [1] Fixes: https://lkml.kernel.org/r/ZzdxKF39VEmXSSyN@tissot.1015granger.net Cc: Chuck Lever chuck.lever@oracle.com Cc: Hugh Dickins hughd@google.com

Acked-by: Hugh Dickins hughd@google.com

Thanks Andrew, I was just in the course of preparing the same to rush to Linus: I'll leave that to you now.

Cc: Jeongjun Park aha310510@gmail.com Cc: Yu Zhao yuzhao@google.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org

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mm/shmem.c | 2 -- 1 file changed, 2 deletions(-)

--- a/mm/shmem.c~mm-revert-mm-shmem-fix-data-race-in-shmem_getattr +++ a/mm/shmem.c @@ -1166,9 +1166,7 @@ static int shmem_getattr(struct mnt_idma stat->attributes_mask |= (STATX_ATTR_APPEND | STATX_ATTR_IMMUTABLE | STATX_ATTR_NODUMP);

• inode_lock_shared(inode); generic_fillattr(idmap, request_mask, inode, stat);
• inode_unlock_shared(inode);

if (shmem_huge_global_enabled(inode, 0, 0, false, NULL, 0)) stat->blksize = HPAGE_PMD_SIZE; _

Patches currently in -mm which might be from akpm@linux-foundation.org are

fs-proc-vmcorec-fix-warning-when-config_mmu=n.patch mm-revert-mm-shmem-fix-data-race-in-shmem_getattr.patch