UPSTREAM: arm/arm64: KVM: Optimize handling of Access Flag faults
Now that we have page aging in Stage-2, it becomes obvious that
we're doing way too much work handling the fault.
The page is not going anywhere (it is still mapped), the page
tables are already allocated, and all we want is to flip a bit
in the PMD or PTE. Also, we can avoid any form of TLB invalidation,
since a page with the AF bit off is not allowed to be cached.
An obvious solution is to have a separate handler for FSC_ACCESS,
where we pride ourselves to only do the very minimum amount of
work.
BUG=chromium:846515
TEST=build/boot on hana with USE=kvm_host
Change-Id: Ic73af1c5df560f1d52c6e03235feab7edca74c23
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
(cherry picked from commit aeda9130c38e2e0e77c1aaa65292c2f5a81107a8)
Signed-off-by: Sonny Rao <sonnyrao@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/1088065
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
2 files changed
