5.8-stable patches

added patches:
	io_uring-no-read-write-retry-on-eagain-error-and-o_nonblock-marked-file.patch

diff --git a/queue-5.8/io_uring-no-read-write-retry-on-eagain-error-and-o_nonblock-marked-file.patch b/queue-5.8/io_uring-no-read-write-retry-on-eagain-error-and-o_nonblock-marked-file.patch
new file mode 100644 (file)
index 0000000..f7f7dfa
--- /dev/null
+++ b/queue-5.8/io_uring-no-read-write-retry-on-eagain-error-and-o_nonblock-marked-file.patch
@@ -0,0 +1,59 @@
+From 355afaeb578abac907217c256a844cfafb0337b2 Mon Sep 17 00:00:00 2001
+From: Jens Axboe <axboe@kernel.dk>
+Date: Wed, 2 Sep 2020 09:30:31 -0600
+Subject: io_uring: no read/write-retry on -EAGAIN error and O_NONBLOCK marked file
+
+From: Jens Axboe <axboe@kernel.dk>
+
+commit 355afaeb578abac907217c256a844cfafb0337b2 upstream.
+
+Actually two things that need fixing up here:
+
+- The io_rw_reissue() -EAGAIN retry is explicit to block devices and
+  regular files, so don't ever attempt to do that on other types of
+  files.
+
+- If we hit -EAGAIN on a nonblock marked file, don't arm poll handler for
+  it. It should just complete with -EAGAIN.
+
+Cc: stable@vger.kernel.org
+Reported-by: Norman Maurer <norman.maurer@googlemail.com>
+Signed-off-by: Jens Axboe <axboe@kernel.dk>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ fs/io_uring.c |   13 +++++++++++++
+ 1 file changed, 13 insertions(+)
+
+--- a/fs/io_uring.c
++++ b/fs/io_uring.c
+@@ -2697,8 +2697,15 @@ static int io_read(struct io_kiocb *req,
+               else
+                       ret2 = -EINVAL;
+ 
++              /* no retry on NONBLOCK marked file */
++              if (ret2 == -EAGAIN && (req->file->f_flags & O_NONBLOCK)) {
++                      ret = 0;
++                      goto done;
++              }
++
+               /* Catch -EAGAIN return for forced non-blocking submission */
+               if (!force_nonblock || ret2 != -EAGAIN) {
++      done:
+                       kiocb_done(kiocb, ret2);
+               } else {
+ copy_iov:
+@@ -2823,7 +2830,13 @@ static int io_write(struct io_kiocb *req
+                */
+               if (ret2 == -EOPNOTSUPP && (kiocb->ki_flags & IOCB_NOWAIT))
+                       ret2 = -EAGAIN;
++              /* no retry on NONBLOCK marked file */
++              if (ret2 == -EAGAIN && (req->file->f_flags & O_NONBLOCK)) {
++                      ret = 0;
++                      goto done;
++              }
+               if (!force_nonblock || ret2 != -EAGAIN) {
++done:
+                       kiocb_done(kiocb, ret2);
+               } else {
+ copy_iov:

diff --git a/queue-5.8/series b/queue-5.8/series
index a3c67d9e3ddea19649274643e9c3a0a433e5f847..855127a5dd9dbe0e955895c165b02479823eb270 100644 (file)
--- a/queue-5.8/series
+++ b/queue-5.8/series
@@ -173,3 +173,4 @@ mm-slub-fix-conversion-of-freelist_corrupted.patch
 mm-track-page-table-modifications-in-__apply_to_page_range.patch
 mm-madvise-fix-vma-user-after-free.patch
 mm-rmap-fixup-copying-of-soft-dirty-and-uffd-ptes.patch
+io_uring-no-read-write-retry-on-eagain-error-and-o_nonblock-marked-file.patch