Re: [PATCH] hibernate: unlock swap bdev for writing when uswsusp is active

Domenico Andreoli
2020-03-04T08:34:15Z

On Tue, Mar 03, 2020 at 05:18:40PM -0800, Darrick J. Wong wrote:
> On Tue, Mar 03, 2020 at 10:51:22PM +0000, Domenico Andreoli wrote:
> >
> > I don't see the need of reverting anything, I can deal with these
> > issues if you are busy on something else.
>
> If you want to work on the patch, please do! Starting from the revert
> patch I sent earlier, I /think/ only the first chunk (the one that
> touches blkdev_write_iter) of that patch actually has to be applied to
> re-enable uswsusp. That could probably be turned into:
>
> if (IS_SWAPFILE(...) && !IS_ENABLED(HIBERNATION))
> return -ETXTBSY;

I've just sent such patch, I don't know how it will play with the whole
revert of yesterday and that akpm has already taken in his tree.

Ideally this should go in 5.6-rc and also in stable kernels > 5.2.

>
> Though perhaps a better thing to check here rather than the Kconfig
> option is whether or not the system is locked out against hibernation?
> e.g.,
>
> if (IS_SWAPFILE(...) && !hibernation_available())
> return -EXTBSY;

This is the kind of improved fix I'm going to prepare for a coming
merge window.

Regards,
Domenico

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