Re: [PATCH] Disable Bus Master on PCI device shutdown

[Andi Kleen]

Alan Cox <alan@xxxxxxxxxxxxxxxxxxx> writes:

>> This protects against the case where a piece of hardware is continuing 
>> to DMA even after the driver shutdown method has been called? I'm not 
>
> It doesn't. We also have hardware which craps itself if you clear the bus
> mastering bit and we have platforms where the BIOS gets most upset if you
> do that on suspend paths. There are also lots of devices that simply
> ignore the bus mastering bit !

But it also makes my system do kexec successfully for the first time.

Maybe can make it an option.

n-Andi

-- 
ak@xxxxxxxxxxxxxxx -- Speaking for myself only
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