[PATCH v3 2/4] xen/balloon: make the balloon wait interruptible

From: Roger Pau Monne
Date: Mon Jul 27 2020 - 05:15:10 EST


So it can be killed, or else processes can get hung indefinitely
waiting for balloon pages.

Signed-off-by: Roger Pau Monnà <roger.pau@xxxxxxxxxx>
Reviewed-by: Juergen Gross <jgross@xxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
---
Cc: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
Cc: Juergen Gross <jgross@xxxxxxxx>
Cc: Stefano Stabellini <sstabellini@xxxxxxxxxx>
Cc: xen-devel@xxxxxxxxxxxxxxxxxxxx
---
drivers/xen/balloon.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c
index 3cb10ed32557..292413b27575 100644
--- a/drivers/xen/balloon.c
+++ b/drivers/xen/balloon.c
@@ -568,11 +568,13 @@ static int add_ballooned_pages(int nr_pages)
if (xen_hotplug_unpopulated) {
st = reserve_additional_memory();
if (st != BP_ECANCELED) {
+ int rc;
+
mutex_unlock(&balloon_mutex);
- wait_event(balloon_wq,
+ rc = wait_event_interruptible(balloon_wq,
!list_empty(&ballooned_pages));
mutex_lock(&balloon_mutex);
- return 0;
+ return rc ? -ENOMEM : 0;
}
}

--
2.27.0