Messages in this thread |  | | Date | Fri, 27 Nov 2020 18:16:35 +0000 | From | Marc Zyngier <> | Subject | Re: [PATCH v4 03/14] KVM: arm64: Kill 32-bit vCPUs on systems with mismatched EL0 support |
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On 2020-11-27 17:24, Quentin Perret wrote: > On Friday 27 Nov 2020 at 17:14:11 (+0000), Marc Zyngier wrote:
[...]
>> Yeah, the sanitized read feels better, if only because that is >> what we are going to read in all the valid cases, unfortunately. >> read_sanitised_ftr_reg() is sadly not designed to be called on >> a fast path, meaning that 32bit guests will do a bsearch() on >> the ID-regs every time they exit... >> >> I guess we will have to evaluate how much we loose with this. > > Could we use the trick we have for arm64_ftr_reg_ctrel0 to speed this > up?
Maybe. I want to first verify whether this has any measurable impact. Another possibility would be to cache the last read_sanitised_ftr_reg() access, just to see if that helps. There shouldn't be that many code paths hammering it.
Thanks,
M. -- Jazz is not dead. It just smells funny...
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