Re: [PATCH] pm-hibernate: flush block device cache when hibernating

Mikulas Patocka <[email protected]> Fri, 31 Oct 2025 20:29:58 +0100 (CET)

Newsgroups	dev.linux.lists.lvm-devel,dev.linux.lists.dm-devel,dev.linux.lists.linux-lvm,org.kernel.vger.linux-block,org.kernel.vger.linux-btrfs,org.kernel.vger.linux-crypto,org.kernel.vger.linux-pm,org.kernel.vger.linux-raid,org.kvack.linux-mm
Message-ID	<[email protected]>


On Mon, 27 Oct 2025, Askar Safin wrote:

> Mikulas Patocka <[email protected]>:
> > Hi
> > 
> > Does this patch fix it?
> > 
> > Mikulas
> > 
> > 
> > From: Mikulas Patocka <[email protected]>
> > 
> > There was reported failure that hibernation doesn't work with 
> > dm-integrity. The reason for the failure is that the hibernation code 
> > doesn't issue the FLUSH bio - the data still sits in the dm-integrity 
> > cache and they are lost when poweroff happens.
> 
> I tested this patch in Qemu on current master (43e9ad0c55a3). Also I
> applied Mario's patch
> https://lore.kernel.org/linux-pm/[email protected]/ .
> It is needed, otherwise you get WARNING when you try to hibernate.
> 
> The patch doesn't work.

Yes, I see - the problem is harder than I thought.

I've created two patches and I tested them that they work. So, you can try 
them.

Mikulas