Re: Regression in suspend to ram in 2.6.31-rc kernels

Zdenek Kabelac
2009-09-14T08:39:42Z

2009/9/12 Rafael J. Wysocki <rjw@sisk.pl>:
> On Saturday 12 September 2009, Chris Ball wrote:
>> Hi,
>>
>>    > Well system could check basic card ids if they match after resume
>>
>> No.  That (arguably) guarantees that it's the same card, but not that
>> it wasn't modified in another machine during the suspend.
>
> Generally speaking, we'd also need to check superblocks for this to work.
>
>>    > if some users wants to crash his card by randomly swapping it
>>    > during suspend/resume - I'd have no problem with that....
>>
>> You should have a problem with it.  Taking a card from a suspended
>> machine and working on it with a different machine is not a bizarre
>> thing to want to do.
>
> Agreed.

Well - ok - so let me ask this question - if I'll replace local hard
drive during suspend - what will happen - is this prohibited by hw
(e.i. to switch SATA cables) ?

IMHO filesystem should be able to detect corruption of its data
structures - (assuming fs is notified about suspend/resume operation)

Also there could be one simple quick solution/hack - to require to
have at least all remote drives unmounted - so suspend would be
refused if it runs mounted card/usb drive - this would be 100% better
than current solution which effectively kills my laptop if I forget to
unmount card in mmc reader - especially if dmesg contains message with
the reason why my suspend fails.

Zdenek