Re: [PATCH v2 2/5] arm64: Work around Falkor erratum 1003

From: Christoffer Dall
Date: Wed Jan 04 2017 - 05:33:36 EST


On Thu, Dec 29, 2016 at 05:43:32PM -0500, Christopher Covington wrote:
> From: Shanker Donthineni <shankerd@xxxxxxxxxxxxxx>
>
> On the Qualcomm Datacenter Technologies Falkor v1 CPU, memory accesses may
> allocate TLB entries using an incorrect ASID when TTBRx_EL1 is being
> updated. Changing the TTBRx_EL1[ASID] and TTBRx_EL1[BADDR] fields
> separately using a reserved ASID will ensure that there are no TLB entries
> with incorrect ASID after changing the the ASID.

When we restore guest state in KVM, we completely save and restore
TTBRx_EL1 from EL2. Would that be affected by this erratum?

Thanks,
-Christoffer