This is a note to let you know that I've just added the patch titled
xen-netback: respect gnttab_map_refs()'s return value
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
xen-netback-respect-gnttab_map_refs-s-return-value.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 2991397d23ec597405b116d96de3813420bdcbc3 Mon Sep 17 00:00:00 2001
From: Jan Beulich <jbeulich@xxxxxxxx>
Date: Thu, 25 Feb 2021 16:35:15 +0100
Subject: xen-netback: respect gnttab_map_refs()'s return value
From: Jan Beulich <jbeulich@xxxxxxxx>
commit 2991397d23ec597405b116d96de3813420bdcbc3 upstream.
Commit 3194a1746e8a ("xen-netback: don't "handle" error by BUG()")
dropped respective a BUG_ON() without noticing that with this the
variable's value wouldn't be consumed anymore. With gnttab_set_map_op()
setting all status fields to a non-zero value, in case of an error no
slot should have a status of GNTST_okay (zero).
This is part of XSA-367.
Cc: <stable@xxxxxxxxxxxxxxx>
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
Reviewed-by: Juergen Gross <jgross@xxxxxxxx>
Link: https://lore.kernel.org/r/d933f495-619a-0086-5fb4-1ec3cf81a8fc@xxxxxxxx
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/xen-netback/netback.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
--- a/drivers/net/xen-netback/netback.c
+++ b/drivers/net/xen-netback/netback.c
@@ -1792,11 +1792,21 @@ int xenvif_tx_action(struct xenvif_queue
return 0;
gnttab_batch_copy(queue->tx_copy_ops, nr_cops);
- if (nr_mops != 0)
+ if (nr_mops != 0) {
ret = gnttab_map_refs(queue->tx_map_ops,
NULL,
queue->pages_to_map,
nr_mops);
+ if (ret) {
+ unsigned int i;
+
+ netdev_err(queue->vif->dev, "Map fail: nr %u ret %d\n",
+ nr_mops, ret);
+ for (i = 0; i < nr_mops; ++i)
+ WARN_ON_ONCE(queue->tx_map_ops[i].status ==
+ GNTST_okay);
+ }
+ }
work_done = xenvif_tx_submit(queue);
Patches currently in stable-queue which might be from jbeulich@xxxxxxxx are
queue-4.4/xen-netback-respect-gnttab_map_refs-s-return-value.patch
queue-4.4/xen-gnttab-handle-p2m-update-errors-on-a-per-slot-basis.patch
