Re: [PATCH 2/2] resume: wait for device probing to finish

["Rafael J. Wysocki" <rjw@sisk.pl>]

On Saturday 10 January 2009, Arjan van de Ven wrote:
> (this patch needs testing on a few different machines; compile tested only)
> 
> 
> From 10b3e25671c817933e232498a56640fd48964345 Mon Sep 17 00:00:00 2001
> From: Arjan van de Ven <arjan@linux.intel.com>
> Date: Fri, 9 Jan 2009 21:11:23 -0800
> Subject: [PATCH] resume: wait for device probing to finish
> 
> the resume code does not currently wait for device probing to finish.
> Even without async function calls this is dicey and not correct,
> but with async function calls during the boot sequence this is going
> to get hit more...
> 
> This patch adds the synchronization using the newly introduced helper.
> 
> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>

Sorry for the delay, but I only could do the testing today.

It appears that 2.6.29-rc1 with the two patches in this series applied resumes
from hibernation correctly.

Please push the second one to Len with my ack.

Thanks,
Rafael


> ---
>  kernel/power/disk.c |   11 +++++++++++
>  1 files changed, 11 insertions(+), 0 deletions(-)
> 
> diff --git a/kernel/power/disk.c b/kernel/power/disk.c
> index 45e8541..d2d24b7 100644
> --- a/kernel/power/disk.c
> +++ b/kernel/power/disk.c
> @@ -585,6 +585,12 @@ static int software_resume(void)
>  	unsigned int flags;
>  
>  	/*
> +	 * If the user said "noresume".. bail out early.
> +	 */
> +	if (noresume)
> +		return 0;
> +
> +	/*
>  	 * name_to_dev_t() below takes a sysfs buffer mutex when sysfs
>  	 * is configured into the kernel. Since the regular hibernate
>  	 * trigger path is via sysfs which takes a buffer mutex before
> @@ -600,6 +606,11 @@ static int software_resume(void)
>  			mutex_unlock(&pm_mutex);
>  			return -ENOENT;
>  		}
> +		/*
> +		 * Some device discovery might still be in progress; we need
> +		 * to wait for this to finish.
> +		 */
> +		wait_for_device_probe();
>  		swsusp_resume_device = name_to_dev_t(resume_file);
>  		pr_debug("PM: Resume from partition %s\n", resume_file);
>  	} else {
> -- 
> 1.6.0.6