Re: [PATCH v11 9/9] arm64: armv8_deprecated: apply FEAT_LSUI for swpX emulation.

Hi Arnd,

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apply FEAT_LSUI instruction to emulate deprecated swpX instruction.

Can you explain in the changrelog why you do this?

In particular, is this a performance optimization or is this required for correctness in some scenario?

I think the main purpose using for this is to "remove the toggling the PSTATE.PAN" bit. so that remove some *potential* problem which can happen when PAN bit is cleared.

Ok, I see. This should definitely be part of the commit log for the patch in addition to the cover letter.

Thanks. I'll add detail in next spin after receving other comments.

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-- Sincerely, Yeoreum Yun