From d9552fe133f9f7c357460b041e2d3b20310adf8d Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Thu, 9 Feb 2023 17:58:16 +0000 Subject: KVM: arm64: nv: Emulate PSTATE.M for a guest hypervisor We can no longer blindly copy the VCPU's PSTATE into SPSR_EL2 and return to the guest and vice versa when taking an exception to the hypervisor, because we emulate virtual EL2 in EL1 and therefore have to translate the mode field from EL2 to EL1 and vice versa. This requires keeping track of the state we enter the guest, for which we transiently use a dedicated flag. Reviewed-by: Russell King (Oracle) Reviewed-by: Alexandru Elisei Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20230209175820.1939006-15-maz@kernel.org Signed-off-by: Oliver Upton --- arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) (limited to 'arch/arm64/kvm/hyp/include') diff --git a/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h b/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h index baa5b9b3dde5..0fbbf2870b7b 100644 --- a/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h +++ b/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h @@ -156,9 +156,26 @@ static inline void __sysreg_restore_el1_state(struct kvm_cpu_context *ctxt) write_sysreg_el1(ctxt_sys_reg(ctxt, SPSR_EL1), SYS_SPSR); } +/* Read the VCPU state's PSTATE, but translate (v)EL2 to EL1. */ +static inline u64 to_hw_pstate(const struct kvm_cpu_context *ctxt) +{ + u64 mode = ctxt->regs.pstate & (PSR_MODE_MASK | PSR_MODE32_BIT); + + switch (mode) { + case PSR_MODE_EL2t: + mode = PSR_MODE_EL1t; + break; + case PSR_MODE_EL2h: + mode = PSR_MODE_EL1h; + break; + } + + return (ctxt->regs.pstate & ~(PSR_MODE_MASK | PSR_MODE32_BIT)) | mode; +} + static inline void __sysreg_restore_el2_return_state(struct kvm_cpu_context *ctxt) { - u64 pstate = ctxt->regs.pstate; + u64 pstate = to_hw_pstate(ctxt); u64 mode = pstate & PSR_AA32_MODE_MASK; /* -- cgit v1.2.3-70-g09d2