The patch titled Subject: cifs: drop the incorrect assertion in cifs_swap_rw() has been added to the -mm mm-hotfixes-unstable branch. Its filename is cifs-drop-the-incorrect-assertion-in-cifs_swap_rw.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: Barry Song v-songbaohua@oppo.com Subject: cifs: drop the incorrect assertion in cifs_swap_rw() Date: Tue, 18 Jun 2024 19:22:58 +1200

Since commit 2282679fb20b ("mm: submit multipage write for SWP_FS_OPS swap-space"), we can plug multiple pages then unplug them all together. That means iov_iter_count(iter) could be way bigger than PAGE_SIZE, it actually equals the size of iov_iter_npages(iter, INT_MAX).

Note this issue has nothing to do with large folios as we don't support THP_SWPOUT to non-block devices.

Link: https://lkml.kernel.org/r/20240618072258.33128-1-21cnbao@gmail.com Fixes: 2282679fb20b ("mm: submit multipage write for SWP_FS_OPS swap-space") Signed-off-by: Barry Song v-songbaohua@oppo.com Reported-by: Christoph Hellwig hch@lst.de Closes: https://lore.kernel.org/linux-mm/20240614100329.1203579-1-hch@lst.de/ Cc: NeilBrown neilb@suse.de Cc: Anna Schumaker anna@kernel.org Cc: Steve French sfrench@samba.org Cc: Trond Myklebust trondmy@kernel.org Cc: Chuanhua Han hanchuanhua@oppo.com Cc: Ryan Roberts ryan.roberts@arm.com Cc: Chris Li chrisl@kernel.org Cc: "Huang, Ying" ying.huang@intel.com Cc: Jeff Layton jlayton@kernel.org Cc: Paulo Alcantara pc@manguebit.com Cc: Ronnie Sahlberg ronniesahlberg@gmail.com Cc: Shyam Prasad N sprasad@microsoft.com Cc: Tom Talpey tom@talpey.com Cc: Bharath SM bharathsm@microsoft.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

fs/smb/client/file.c | 2 -- 1 file changed, 2 deletions(-)

--- a/fs/smb/client/file.c~cifs-drop-the-incorrect-assertion-in-cifs_swap_rw +++ a/fs/smb/client/file.c @@ -3200,8 +3200,6 @@ static int cifs_swap_rw(struct kiocb *io { ssize_t ret;

- WARN_ON_ONCE(iov_iter_count(iter) != PAGE_SIZE); - if (iov_iter_rw(iter) == READ) ret = netfs_unbuffered_read_iter_locked(iocb, iter); else _

Patches currently in -mm which might be from v-songbaohua@oppo.com are

cifs-drop-the-incorrect-assertion-in-cifs_swap_rw.patch mm-remove-the-implementation-of-swap_free-and-always-use-swap_free_nr.patch mm-introduce-pte_move_swp_offset-helper-which-can-move-offset-bidirectionally.patch mm-introduce-arch_do_swap_page_nr-which-allows-restore-metadata-for-nr-pages.patch mm-swap-reuse-exclusive-folio-directly-instead-of-wp-page-faults.patch mm-introduce-pmdpte_needs_soft_dirty_wp-helpers-for-softdirty-write-protect.patch mm-set-pte-writable-while-pte_soft_dirty-is-true-in-do_swap_page.patch