Module Name: src
Committed By: bouyer
Date: Mon Jul 17 10:12:54 UTC 2023
Modified Files:
src/sys/arch/xen/xen: xen_clock.c
Log Message:
Unmask event after arming the one-shot timer in clock initialisation,
to avoid a possible race with xen_timer_handler() updating
ci_xen_hardclock_systime_ns while we're reading it.
Pointed out by Taylor R Campbell
To generate a diff of this commit:
cvs rdiff -u -r1.11 -r1.12 src/sys/arch/xen/xen/xen_clock.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/xen_clock.c
diff -u src/sys/arch/xen/xen/xen_clock.c:1.11 src/sys/arch/xen/xen/xen_clock.c:1.12
--- src/sys/arch/xen/xen/xen_clock.c:1.11 Thu Jul 13 13:34:15 2023
+++ src/sys/arch/xen/xen/xen_clock.c Mon Jul 17 10:12:54 2023
@@ -1,4 +1,4 @@
-/* $NetBSD: xen_clock.c,v 1.11 2023/07/13 13:34:15 riastradh Exp $ */
+/* $NetBSD: xen_clock.c,v 1.12 2023/07/17 10:12:54 bouyer Exp $ */
/*-
* Copyright (c) 2017, 2018 The NetBSD Foundation, Inc.
@@ -36,7 +36,7 @@
#endif
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: xen_clock.c,v 1.11 2023/07/13 13:34:15 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: xen_clock.c,v 1.12 2023/07/17 10:12:54 bouyer Exp $");
#include <sys/param.h>
#include <sys/types.h>
@@ -729,12 +729,12 @@ xen_resumeclocks(struct cpu_info *ci)
/* Pretend the last hardclock happened right now. */
ci->ci_xen_hardclock_systime_ns = xen_vcputime_systime_ns();
- hypervisor_unmask_event(evtch);
/* Arm the one-shot timer. */
error = HYPERVISOR_set_timer_op(ci->ci_xen_hardclock_systime_ns +
NS_PER_TICK);
KASSERT(error == 0);
+ hypervisor_unmask_event(evtch);
/* We'd better not have switched CPUs. */
KASSERT(ci == curcpu());
