Module Name: src
Committed By: bouyer
Date: Sun Sep 4 11:20:33 UTC 2022
Modified Files:
src/sys/arch/xen/xen: xenevt.c
Log Message:
Release mutexes earlier in xenevt_free(), to call *destroy and kmem_free
without holding spin locks. Fixes an occasional deadlock seen when the qemu
backing a HVM domU exits.
To generate a diff of this commit:
cvs rdiff -u -r1.65 -r1.66 src/sys/arch/xen/xen/xenevt.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/xen/xen/xenevt.c
diff -u src/sys/arch/xen/xen/xenevt.c:1.65 src/sys/arch/xen/xen/xenevt.c:1.66
--- src/sys/arch/xen/xen/xenevt.c:1.65 Fri May 27 18:35:38 2022
+++ src/sys/arch/xen/xen/xenevt.c Sun Sep 4 11:20:33 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: xenevt.c,v 1.65 2022/05/27 18:35:38 bouyer Exp $ */
+/* $NetBSD: xenevt.c,v 1.66 2022/09/04 11:20:33 bouyer Exp $ */
/*
* Copyright (c) 2005 Manuel Bouyer.
@@ -26,7 +26,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: xenevt.c,v 1.65 2022/05/27 18:35:38 bouyer Exp $");
+__KERNEL_RCSID(0, "$NetBSD: xenevt.c,v 1.66 2022/09/04 11:20:33 bouyer Exp $");
#include "opt_xen.h"
#include <sys/param.h>
@@ -278,8 +278,7 @@ xenevt_notify(void)
d->pending = false;
mutex_enter(&d->lock);
if (d->flags & XENEVT_F_FREE) {
- xenevt_free(d);
- mutex_exit(&devevent_lock);
+ xenevt_free(d); /* releases devevent_lock */
} else {
mutex_exit(&devevent_lock);
selnotify(&d->sel, 0, 1);
@@ -402,7 +401,6 @@ xenevt_free(struct xenevt_d *d)
hypervisor_mask_event(i);
xen_atomic_clear_bit(&d->ci->ci_evtmask[0], i);
devevent[i] = NULL;
-
op.cmd = EVTCHNOP_close;
op.u.close.port = i;
if ((error = HYPERVISOR_event_channel_op(&op))) {
@@ -412,6 +410,7 @@ xenevt_free(struct xenevt_d *d)
}
}
mutex_exit(&d->lock);
+ mutex_exit(&devevent_lock);
seldestroy(&d->sel);
cv_destroy(&d->cv);
mutex_destroy(&d->lock);
@@ -428,11 +427,11 @@ xenevt_fclose(struct file *fp)
if (d->pending) {
d->flags |= XENEVT_F_FREE;
mutex_exit(&d->lock);
+ mutex_exit(&devevent_lock);
} else {
- xenevt_free(d);
+ xenevt_free(d); /* releases devevent_lock */
}
- mutex_exit(&devevent_lock);
fp->f_data = NULL;
return (0);
}
