The kprobe enablement work has uncovered that changes made by
a guest to MDSCR_EL1 were propagated to the host when VHE was
enabled, leading to unexpected exception being delivered.
Moving this register to the list of registers that are always
context-switched fixes the issue.
Fixes: 9c6c356832 ("arm64: KVM: VHE: Split save/restore of registers shared between guest and host")
Cc: stable@vger.kernel.org #4.6
Reported-by: Tirumalesh Chalamarla <Tirumalesh.Chalamarla@cavium.com>
Tested-by: Tirumalesh Chalamarla <Tirumalesh.Chalamarla@cavium.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
In order to be able to move code outside of kvm/hyp, we need to make
the global hyp.h file accessible from a standard location.
include/asm/kvm_hyp.h seems good enough.
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
We're now in a position where we can introduce VHE's minimal
save/restore, which is limited to the handful of shared sysregs.
Add the required alternative function calls that result in a
"do nothing" call on VHE, and the normal save/restore for non-VHE.
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Use the recently introduced unified system register accessors for
those sysregs that behave differently depending on VHE being in
use or not.
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
A handful of system registers are still shared between host and guest,
even while using VHE (tpidr*_el[01] and actlr_el1).
Also, some of the vcpu state (sp_el0, PC and PSTATE) must be
save/restored on entry/exit, as they are used on the host as well.
In order to facilitate the introduction of a VHE-specific sysreg
save/restore, make move the access to these registers to their
own save/restore functions.
No functional change.
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
With ARMv8, host and guest share the same system register file,
making the save/restore procedure completely symetrical.
With VHE, host and guest now have different requirements, as they
use different sysregs.
In order to prepare for this, add split sysreg save/restore functions
for both host and guest. No functional changes yet.
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Having the system register numbers as #defines has been a pain
since day one, as the ordering is pretty fragile, and moving
things around leads to renumbering and epic conflict resolutions.
Now that we're mostly acessing the sysreg file in C, an enum is
a much better type to use, and we can clean things up a bit.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Implement the fpsimd save restore, keeping the lazy part in
assembler (as returning to C would be overkill).
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Implement the 32bit system register save/restore as a direct
translation of the assembly code version.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Implement the system register save/restore as a direct translation of
the assembly code version.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Marc Zyngier