xen: improve error handling in do_suspend. (65f63384) · Commits · 戴 / test

The existing error handling has a few issues: - If freeze_processes() fails it exits with shutting_down = SHUTDOWN_SUSPEND. - If dpm_suspend_noirq() fails it exits without resuming xenbus. - If stop_machine() fails it exits without resuming xenbus or calling dpm_resume_end(). - xs_suspend()/xs_resume() and dpm_suspend_noirq()/dpm_resume_noirq() were not nested in the obvious way. Fix by ensuring each failure case goto's the correct label. Treat a failure of stop_machine() as a cancelled suspend in order to follow the correct resume path. Signed-off-by:

Ian Campbell <ian.campbell@citrix.com> Signed-off-by:

Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: Stable Kernel <stable@kernel.org>

drivers/xen/manage.c

+11 −9

Original line number	Diff line number	Diff line
		@@ -86,32 +86,32 @@ static void do_suspend(void)
		err = freeze_processes();
		if (err) {
		printk(KERN_ERR "xen suspend: freeze failed %d\n", err);
		return;
		goto out;
		}
		#endif

		err = dpm_suspend_start(PMSG_SUSPEND);
		if (err) {
		printk(KERN_ERR "xen suspend: dpm_suspend_start %d\n", err);
		goto out;
		goto out_thaw;
		}

		printk(KERN_DEBUG "suspending xenstore...\n");
		xs_suspend();

		err = dpm_suspend_noirq(PMSG_SUSPEND);
		if (err) {
		printk(KERN_ERR "dpm_suspend_noirq failed: %d\n", err);
		goto resume_devices;
		goto out_resume;
		}

		printk(KERN_DEBUG "suspending xenstore...\n");
		xs_suspend();

		err = stop_machine(xen_suspend, &cancelled, cpumask_of(0));

		dpm_resume_noirq(PMSG_RESUME);

		if (err) {
		printk(KERN_ERR "failed to start xen_suspend: %d\n", err);
		goto out;
		cancelled = 1;
		}

		if (!cancelled) {
		@@ -120,15 +120,17 @@ static void do_suspend(void)
		} else
		xs_suspend_cancel();

		resume_devices:
		out_resume:
		dpm_resume_end(PMSG_RESUME);

		/* Make sure timer events get retriggered on all CPUs */
		clock_was_set();
		out:

		out_thaw:
		#ifdef CONFIG_PREEMPT
		thaw_processes();
		#endif
		out:
		shutting_down = SHUTDOWN_INVALID;
		}
		#endif /* CONFIG_PM_SLEEP */

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