Re: [PATCH] xen/arm: optee: Fix arm_smccc_smc's a0 for OPTEE_SMC_DISABLE_SHM_CACHE

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Wed, 6 Oct 2021, Julien Grall wrote:
> Hi Stefano,
> 
> On 28/09/2021 06:52, Stefano Stabellini wrote:
> > On Mon, 27 Sep 2021, Oleksandr Tyshchenko wrote:
> > > From: Oleksandr Tyshchenko <oleksandr_tyshchenko@xxxxxxxx>
> > > 
> > > Fix a possible copy-paste error in arm_smccc_smc's first argument (a0)
> > > for OPTEE_SMC_DISABLE_SHM_CACHE case.
> > > 
> > > This error causes Linux > v5.14-rc5
> > > (b5c10dd04b7418793517e3286cde5c04759a86de
> > > optee: Clear stale cache entries during initialization) to stuck
> > > repeatedly issuing OPTEE_SMC_DISABLE_SHM_CACHE call and waiting for
> > > the result to be OPTEE_SMC_RETURN_ENOTAVAIL which will never happen.
> > > 
> > > Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@xxxxxxxx>
> > 
> > Acked-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>
> > 
> > I added Fixes: and Backport: tags to the commit
> Per SUPPORT.MD, OP-TEE is still a technical preview. So I would argue that we
> should not do any backport because the feature itself is not officially
> considered supported.

Good point!


> That said, what's missing to make the feature officially supported?

If Oleksandr is also happy to make OP-TEE support in Xen "Supported" in
SUPPORT.md I'd be happy with that too. Specifically I suggest to change
it to:

Status: Supported, not security supported

Security Support is a bit of a heavy process and I am thinking that
"Supported, not security supported" would be an excellent next step.