Hi Christoffer,

On 01/04/2017 05:33 AM, Christoffer Dall wrote:

On Thu, Dec 29, 2016 at 05:43:32PM -0500, Christopher Covington wrote:

quoted

From: Shanker Donthineni <redacted>

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?

Good question, but apparently not. I'll add the following explanation to the
v3 commit message.

"EL2 and EL3 code changing the EL1&0 ASID is not subject to this erratum
because hardware is prohibited from performing translations from an
out-of-context translation regime."

Thanks,
Cov

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