Re: [PATCH 3/5] libata: Implement disk shock protection support

From: Tejun Heo
Date: Mon Aug 04 2008 - 10:36:36 EST


Gabor Gombas wrote:
> On Fri, Aug 01, 2008 at 04:19:26PM +0900, Tejun Heo wrote:
>
>> However, SATA or not, there simply isn't a way to abort commands in ATA.
>> Issuing random command while other commands are in progress simply is
>> state machine violation and there will be many interesting results
>> including complete system lockup (ATA controller dying while holding the
>> PCI bus).
>
> A system lockup may be an acceptable compromise if that saves the
> hardware. Maybe the kernel should explicitely panic unless the
> controller/drive is known to be able to recover.

Such lockups usually would occur before the intervening command is
successfully issued. HSM violation occurs when the driver asks the
controller to send another command while it's already processing another
command. Heh... panicking on accelerometer would be fun tho. We're
gonna get ourselves really flamewars on just about every linux news site.

--
tejun
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