Re: [PATCH 2/3] xen/arm: Advertise workaround 1 if we apply 3

[Julien Grall <julien@xxxxxxx>]

On 04/05/2022 08:25, Bertrand Marquis wrote:
> Hi Julien,
Hi Bertrand,

> > On 3 May 2022, at 19:17, Julien Grall <julien@xxxxxxx> wrote:
> >
> > Hi Bertrand,
> >
> > On 03/05/2022 10:38, Bertrand Marquis wrote:
> > > SMCC_WORKAROUND_3 is handling both Spectre v2 and spectre BHB.
> > > So when a guest is asking if we support workaround 1, tell yes if we
> > > apply workaround 3 on exception entry as it handles it.
> > > This will allow guests not supporting Spectre BHB but impacted by
> > > spectre v2 to still handle it correctly.
> > > The modified behaviour is coherent with what the Linux kernel does in
> > > KVM for guests.
> > > While there use ARM_SMCCC_SUCCESS instead of 0 for the return code value
> > > for workaround detection to be coherent with Workaround 2 handling.
> > > Signed-off-by: Bertrand Marquis <bertrand.marquis@xxxxxxx>
> > Acked-by: Julien Grall <jgrall@xxxxxxxxxx>
> Thanks
>
> > I think we should also consider for backport.
> Agree.
I have committed this patch and added to my list of backport candidate.

Cheers,

--
Julien Grall