when AOP_WRITEPAGE_ACTIVATE is returned (as NFS does when it detects congestion) it is important that the page is redirtied. nfs_writepage_locked() doesn't do this, so files can become corrupted as writes can be lost.

Note that this is not needed in v6.8 as AOP_WRITEPAGE_ACTIVATE cannot be returned. It is needed for kernels v5.18..v6.7. From 6.3 onward the patch is different as it needs to mention "folio", not "page".

Reported-and-tested-by: Jacek Tomaka Jacek.Tomaka@poczta.fm Fixes: 6df25e58532b ("nfs: remove reliance on bdi congestion") Signed-off-by: NeilBrown neilb@suse.de --- fs/nfs/write.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/nfs/write.c b/fs/nfs/write.c index f41d24b54fd1..6a0606668417 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -667,8 +667,10 @@ static int nfs_writepage_locked(struct page *page, int err;

if (wbc->sync_mode == WB_SYNC_NONE && - NFS_SERVER(inode)->write_congested) + NFS_SERVER(inode)->write_congested) { + redirty_page_for_writepage(wbc, page); return AOP_WRITEPAGE_ACTIVATE; + }

nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE); nfs_pageio_init_write(&pgio, inode, 0,