| Message ID | 1472740143-40061-1-git-send-email-vladimir.murzin@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 01/09/16 15:29, Vladimir Murzin wrote: > SCTLR_EL2.SPAN bit controls what happens with the PSTATE.PAN bit on an > exception. However, this bit has no effect on the PSTATE.PAN when > HCR_EL2.E2H or HCR_EL2.TGE is unset. Thus when VHE is used and > exception taken from a guest PSTATE.PAN bit left unchanged and we > continue with a value guest has set. > > To address that always reset PSTATE.PAN on entry from EL1. > > Fixes: 1f364c8c48a0 ("arm64: VHE: Add support for running Linux in EL2 mode") > > Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> > Reviewed-by: James Morse <james.morse@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> M.
diff --git a/arch/arm64/kvm/hyp/entry.S b/arch/arm64/kvm/hyp/entry.S index ce9e5e5..eaf08d3 100644 --- a/arch/arm64/kvm/hyp/entry.S +++ b/arch/arm64/kvm/hyp/entry.S @@ -98,6 +98,8 @@ ENTRY(__guest_exit) // x4-x29,lr: vcpu regs // vcpu x0-x3 on the stack + ALTERNATIVE(nop, SET_PSTATE_PAN(1), ARM64_HAS_PAN, CONFIG_ARM64_PAN) + add x2, x0, #VCPU_CONTEXT stp x4, x5, [x2, #CPU_XREG_OFFSET(4)]
SCTLR_EL2.SPAN bit controls what happens with the PSTATE.PAN bit on an exception. However, this bit has no effect on the PSTATE.PAN when HCR_EL2.E2H or HCR_EL2.TGE is unset. Thus when VHE is used and exception taken from a guest PSTATE.PAN bit left unchanged and we continue with a value guest has set. To address that always reset PSTATE.PAN on entry from EL1. Fixes: 1f364c8c48a0 ("arm64: VHE: Add support for running Linux in EL2 mode") Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Reviewed-by: James Morse <james.morse@arm.com> --- arch/arm64/kvm/hyp/entry.S | 2 ++ 1 file changed, 2 insertions(+)