Hi Marc,
On 2018/11/23 17:10, Marc Zyngier wrote:
> On 23/11/2018 01:25, Hanjun Guo wrote:
>> On 2018/10/31 22:04, David Long wrote:
>>> From: "David A. Long" <dave.long@xxxxxxxxxx>
>>>
>>> V4.4 backport of spectre patches from Russell M. King's spectre branch.
>>> Most KVM patches are excluded. Patches not yet in upstream are excluded.
>>
>> I tested this patch set on top of stable 4.4 kernel, running on boards with
>> A9 and A15 based Hisilicon SoCs, didn't see boot regression and other function
>> regressions in our CI system,
>>
>> Tested-by: Hanjun Guo <hanjun.guo@xxxxxxxxxx>
>>
>> Since this patch set didn't include PSCI based hardening for arm32, so
>> bugfix 6282e916f774 ("ARM: 8809/1: proc-v7: fix Thumb annotation of
>> cpu_v7_hvc_switch_mm") is not needed for this patch set and this patch
>> set is in a good shape I think. So what's the plan for this patch set?
>
> Well, not having these patches means that a 32bit kernel won't be get
> any Spectre-v2 mitigation when run as a guest on an arm64 platform. It
> turns out that this is a pretty common setup among people building large
> pieces of SW, such as distributions.
I almost miss this point, that makes sense to me :)
>
> Not having KVM host mitigation on 32bit ARM is probably OK (let's face
> it, I'm the only user), but not mitigating it as a guest doesn't seem
> completely OK to me.
We are working on a patch set which is backported from mainline to fix
ARM64 spectre-v1, spectre-v2 and SSBD for stable 4.4 kernel, and that
patch set (almost done) has PSCI patches which is needed by 32bit ARM,
so how about posting those ARM64 spectre fixes then backport all those
kvm patches for 32bit ARM spectre fix as well?
Thanks
Hanjun
