From: Roger Pau Monne <roger.pau@citrix.com> commit 88a479ff6ef8af7f07e11593d58befc644244ff7 upstream. So it can be killed, or else processes can get hung indefinitely waiting for balloon pages. Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200727091342.52325-3-roger.pau@citrix.com Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> --- 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 6e89b6ab1d3e8..b23edf64c2b21 100644 --- a/drivers/xen/balloon.c +++ b/drivers/xen/balloon.c @@ -570,11 +570,13 @@ 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; } } -- 2.25.1