6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Christoph Hellwig <hch@xxxxxx> commit 54e7d59841dab977f6cb1183d658b1b82c9f4e94 upstream. 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. [v-songbaohua@xxxxxxxx: figure out the cause and correct the commit message] Link: https://lkml.kernel.org/r/20240618065647.21791-1-21cnbao@xxxxxxxxx Fixes: 2282679fb20b ("mm: submit multipage write for SWP_FS_OPS swap-space") Signed-off-by: Christoph Hellwig <hch@xxxxxx> Signed-off-by: Barry Song <v-songbaohua@xxxxxxxx> Closes: https://lore.kernel.org/linux-mm/20240617053201.GA16852@xxxxxx/ Reviewed-by: Martin Wege <martin.l.wege@xxxxxxxxx> Cc: NeilBrown <neilb@xxxxxxx> Cc: Anna Schumaker <anna@xxxxxxxxxx> Cc: Steve French <sfrench@xxxxxxxxx> Cc: Trond Myklebust <trondmy@xxxxxxxxxx> Cc: Chuanhua Han <hanchuanhua@xxxxxxxx> Cc: Ryan Roberts <ryan.roberts@xxxxxxx> Cc: Chris Li <chrisl@xxxxxxxxxx> Cc: "Huang, Ying" <ying.huang@xxxxxxxxx> Cc: Jeff Layton <jlayton@xxxxxxxxxx> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/nfs/direct.c | 2 -- 1 file changed, 2 deletions(-) --- a/fs/nfs/direct.c +++ b/fs/nfs/direct.c @@ -131,8 +131,6 @@ int nfs_swap_rw(struct kiocb *iocb, stru { ssize_t ret; - VM_BUG_ON(iov_iter_count(iter) != PAGE_SIZE); - if (iov_iter_rw(iter) == READ) ret = nfs_file_direct_read(iocb, iter, true); else