tree 6cfdd09210d75fd2144e44700e6d6a4a3ccde084
parent f5cb6bf173ea17e35466ad35c36b4fa70f1655cb
author Marc Zyngier <marc.zyngier@arm.com> 1527595877 +0100
committer Marc Zyngier <marc.zyngier@arm.com> 1532079289 +0100

arm64: KVM: Handle guest's ARCH_WORKAROUND_2 requests

commit b4f18c063a13dfb33e3a63fe1844823e19c2265e upstream.

In order to forward the guest's ARCH_WORKAROUND_2 calls to EL3,
add a small(-ish) sequence to handle it at EL2. Special care must
be taken to track the state of the guest itself by updating the
workaround flags. We also rely on patching to enable calls into
the firmware.

Note that since we need to execute branches, this always executes
after the Spectre-v2 mitigation has been applied.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>