[PATCH]Teach drivers don't call may-sleep routines in resume code

[PATCH]Teach drivers don't call may-sleep routines in resume code

[Li Shaohua]

Hi,
We already found one driver (PCI link device driver) does the odd thing, so alert other drivers.

Thanks,
Shaohua

--- 2.6/Documentation/power/devices.txt.orig	2004-11-17 10:42:25.160212832 +0800
+++ 2.6/Documentation/power/devices.txt	2004-11-17 10:46:11.070869192 +0800
@@ -70,6 +70,9 @@ System devices will only be suspended wi
 after all other devices have been suspended. On resume, they will be
 resumed before any other devices, and also with interrupts disabled.
 
+*CAUTION*: The resume methods of drivers (normal devices and system devices)
+should never use any may-sleep methods, since when resume from memory (S3),
+no task is running.
 
 Runtime Power Management
 

Re: [PATCH]Teach drivers don't call may-sleep routines in resume code

[Li Shaohua]

On Wed, 2004-11-17 at 11:04, Li Shaohua wrote:
> Hi,
> We already found one driver (PCI link device driver) does the odd thing, so alert other drivers.
> 
> Thanks,
> Shaohua
> 
> --- 2.6/Documentation/power/devices.txt.orig	2004-11-17 10:42:25.160212832 +0800
> +++ 2.6/Documentation/power/devices.txt	2004-11-17 10:46:11.070869192 +0800
> @@ -70,6 +70,9 @@ System devices will only be suspended wi
>  after all other devices have been suspended. On resume, they will be
>  resumed before any other devices, and also with interrupts disabled.
>  
> +*CAUTION*: The resume methods of drivers (normal devices and system devices)
> +should never use any may-sleep methods, since when resume from memory (S3),
> +no task is running.
Oops, the description isn't precise. Some may-sleep routines such as
waiting a sempahore are ok in resume routines, but some (kmalloc) are
bad. Please ignore it till I get a precise description.

Thanks,
Shaohua