| Message ID | 1407358476-21758-1-git-send-email-kamal@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/drivers/xen/manage.c b/drivers/xen/manage.c index 624e8dc..0bc8086 100644 --- a/drivers/xen/manage.c +++ b/drivers/xen/manage.c @@ -95,7 +95,6 @@ static int xen_suspend(void *data) if (!si->cancelled) { xen_irq_resume(); - xen_console_resume(); xen_timer_resume(); } @@ -152,6 +151,10 @@ static void do_suspend(void) err = stop_machine(xen_suspend, &si, cpumask_of(0)); + /* Resume console as early as possible. */ + if (!si.cancelled) + xen_console_resume(); + dpm_resume_start(si.cancelled ? PMSG_THAW : PMSG_RESTORE); if (err) {
This is a note to let you know that I have just added a patch titled xen/manage: fix potential deadlock when resuming the console to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue This patch is scheduled to be released in version 3.13.11.6. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.13.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From f88169fedd5e3530b687bfe01f5907b981ef6b4f Mon Sep 17 00:00:00 2001 From: David Vrabel <david.vrabel@citrix.com> Date: Wed, 2 Jul 2014 17:25:23 +0100 Subject: xen/manage: fix potential deadlock when resuming the console commit 1b6478231c6f5f844185acb32045cf195028cfce upstream. Calling xen_console_resume() in xen_suspend() causes a warning because it locks irq_mapping_update_lock (a mutex) and this may sleep. If a userspace process is using the evtchn device then this mutex may be locked at the point of the stop_machine() call and xen_console_resume() would then deadlock. Resuming the console after stop_machine() returns avoids this deadlock. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/xen/manage.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) -- 1.9.1