The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From f4340e9314dbfadc48758945f85fc3b16612d06f Mon Sep 17 00:00:00 2001
From: Trond Myklebust trond.myklebust@hammerspace.com Date: Mon, 12 Aug 2019 15:19:54 -0400 Subject: [PATCH] NFSv4/pnfs: Fix a page lock leak in nfs_pageio_resend()
If the attempt to resend the pages fails, we need to ensure that we clean up those pages that were not transmitted.
Fixes: d600ad1f2bdb ("NFS41: pop some layoutget errors to application") Signed-off-by: Trond Myklebust trond.myklebust@hammerspace.com Cc: stable@vger.kernel.org # v4.5+
diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c index ed4e1b07447b..15c254753f88 100644 --- a/fs/nfs/pagelist.c +++ b/fs/nfs/pagelist.c @@ -1251,20 +1251,22 @@ static void nfs_pageio_complete_mirror(struct nfs_pageio_descriptor *desc, int nfs_pageio_resend(struct nfs_pageio_descriptor *desc, struct nfs_pgio_header *hdr) { - LIST_HEAD(failed); + LIST_HEAD(pages);
desc->pg_io_completion = hdr->io_completion; desc->pg_dreq = hdr->dreq; - while (!list_empty(&hdr->pages)) { - struct nfs_page *req = nfs_list_entry(hdr->pages.next); + list_splice_init(&hdr->pages, &pages); + while (!list_empty(&pages)) { + struct nfs_page *req = nfs_list_entry(pages.next);
if (!nfs_pageio_add_request(desc, req)) - nfs_list_move_request(req, &failed); + break; } nfs_pageio_complete(desc); - if (!list_empty(&failed)) { - list_move(&failed, &hdr->pages); - return desc->pg_error < 0 ? desc->pg_error : -EIO; + if (!list_empty(&pages)) { + int err = desc->pg_error < 0 ? desc->pg_error : -EIO; + hdr->completion_ops->error_cleanup(&pages, err); + return err; } return 0; }