Re: [PATCH 2/2] pm_trace: Add sysfs attr for rechecking dev hash.

[Pavel Machek <pavel@ucw.cz>]

Hi!

> If the device which fails to resume is part of a loadable kernel module
> it won't be checked at startup against the magic number stored in the
> RTC.
> 
> Add a read-only sysfs attribute /sys/power/pm_trace_dev_hash which
> contains a list of newline separated devices (usually just the one)
> which currently match the last magic number. This allows the device
> which is failing to resume to be found after the modules are loaded
> again.

> --- a/Documentation/power/s2ram.txt
> +++ b/Documentation/power/s2ram.txt
> @@ -49,6 +49,13 @@ machine that doesn't boot) is:
>     device (lspci and /sys/devices/pci* is your friend), and see if you can
>     fix it, disable it, or trace into its resume function.
>  
> +   If no device matches the hash, it may be a device from a loadable kernel
> +   module that is not loaded until after the hash is checked. You can check
> +   the hash against the current devices again after more modules are loaded
> +   using sysfs:
> +
> +	cat /sys/power/pm_trace_dev_hash
> +

Yep, but exact semantics of that sysfs file should probably be linked
in the sysfs documentation...
								Pavel
-- 
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