Re: [PATCH 1/2] Freezer: Fix s2disk resume from initrd (rev. 2)

Pavel Machek
2007-11-22T09:50:59Z

Hi!

> Add appropriate freezer annotations to handle_initrd(), so that it's possible
> to resume from disk from an initrd.
>
> This patch fixes Bug #9345: http://bugzilla.kernel.org/show_bug.cgi?id=9345

Unfortunately, bugzilla does not help me in understanding this.

> Index: linux-2.6/init/do_mounts_initrd.c
> ===================================================================
> --- linux-2.6.orig/init/do_mounts_initrd.c
> +++ linux-2.6/init/do_mounts_initrd.c
> @@ -55,12 +55,18 @@ static void __init handle_initrd(void)
> sys_mount(".", "/", NULL, MS_MOVE, NULL);
> sys_chroot(".");
>
> + /*
> + * In case that a resume from disk is carried out by linuxrc or one of
> + * its children, we need to tell the freezer not to wait for us.
> + */
> + current->flags |= PF_FREEZER_SKIP;
> +
> pid = kernel_thread(do_linuxrc, "/linuxrc", SIGCHLD);
> if (pid > 0)
> - while (pid != sys_wait4(-1, NULL, 0, NULL)) {
> - try_to_freeze();
> + while (pid != sys_wait4(-1, NULL, 0, NULL))
> yield();
> - }
> +
> + current->flags &= ~PF_FREEZER_SKIP;

New code should work (but it is uglier than the old one). What was
wrong with the old one? Refrigerator should make sys_wait4() return,
and that it turn should put handle_initrd() into refrigerator...

Pavel
--
(english) http://www.livejournal.com/~pavelmachek
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