Re: Intel QAT on A2SDi-8C-HLN4F causes massive data corruption with dm-crypt + xfs

[Greg KH <gregkh@linuxfoundation.org>]

On Wed, Mar 02, 2022 at 11:49:16AM +0000, Giovanni Cabiddu wrote:
> Hi Greg,
> 
> On Wed, Mar 02, 2022 at 11:29:00AM +0100, Greg KH wrote:
> > On Tue, Mar 01, 2022 at 04:11:13PM +1200, Herbert Xu wrote:
> > > On Mon, Feb 28, 2022 at 05:12:20PM -0800, Linus Torvalds wrote:
> > > > 
> > > > It sounds like it was incidental and almost accidental that it fixed
> > > > that thing, and nobody realized it should perhaps be also moved to
> > > > stable.
> > > 
> > > Yes this was incidental.  The patch in question fixes an issue in
> > > OOM situations where drivers that must allocate memory on each
> > > request may lead to dead-lock so it's not really targeted at qat.
> > 
> > Ok, so what commits should I backport to kernels older than 5.10 to
> > resolve this?
> Is it possible to wait for a set that resolves the problem rather than
> backporting the patches that disables the use-case?

It's already disabled in newer kernels, so we should do so for older
ones to prevent problems and the delay in getting those potential fixes
merged some day in the future.

> I have a patchset that fixes the actual issue and we are doing an
> internal review before submission to the mailing list.
> I should be able to send a V1 out between today and tomorrow.
> 
> If not, then these are the patches that should be backported:
>     7bcb2c99f8ed crypto: algapi - use common mechanism for inheriting flags
>     2eb27c11937e crypto: algapi - add NEED_FALLBACK to INHERITED_FLAGS
>     fbb6cda44190 crypto: algapi - introduce the flag CRYPTO_ALG_ALLOCATES_MEMORY
>     b8aa7dc5c753 crypto: drivers - set the flag CRYPTO_ALG_ALLOCATES_MEMORY
>     cd74693870fb dm crypt: don't use drivers that have CRYPTO_ALG_ALLOCATES_MEMORY
> Herbert, correct me if I'm wrong here.

These need to be manually backported as they do not apply cleanly.  Can
you provide such a set?  Or should I just disable a specific driver here
instead which would be easier overall?

thanks,

greg k-h