diff options
| author | Oliver Upton <oliver.upton@linux.dev> | 2024-12-19 14:41:11 -0800 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2024-12-20 09:02:51 +0000 |
| commit | 4ad3a0b87f2ec4714fdfa6bd5de57b4c30e15753 (patch) | |
| tree | 20adfeb8016ea10554c953c485a698e61d92bee4 /arch/arm64/kvm/hyp/include | |
| parent | 75a5fbaf6623328d3ac69719145c2247f7b4e299 (diff) | |
KVM: arm64: Don't hijack guest context MDSCR_EL1
Stealing MDSCR_EL1 in the guest's kvm_cpu_context for external debugging
is rather gross. Just add a field for this instead and let the context
switch code pick the correct one based on the debug owner.
Tested-by: James Clark <james.clark@linaro.org>
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20241219224116.3941496-15-oliver.upton@linux.dev
Signed-off-by: Marc Zyngier <maz@kernel.org>
Diffstat (limited to 'arch/arm64/kvm/hyp/include')
| -rw-r--r-- | arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h | 39 |
1 files changed, 27 insertions, 12 deletions
diff --git a/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h b/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h index a998b2f6abcb..76ff095c6b6e 100644 --- a/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h +++ b/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h @@ -18,9 +18,34 @@ static inline bool ctxt_has_s1poe(struct kvm_cpu_context *ctxt); +static inline struct kvm_vcpu *ctxt_to_vcpu(struct kvm_cpu_context *ctxt) +{ + struct kvm_vcpu *vcpu = ctxt->__hyp_running_vcpu; + + if (!vcpu) + vcpu = container_of(ctxt, struct kvm_vcpu, arch.ctxt); + + return vcpu; +} + +static inline bool ctxt_is_guest(struct kvm_cpu_context *ctxt) +{ + return host_data_ptr(host_ctxt) != ctxt; +} + +static inline u64 *ctxt_mdscr_el1(struct kvm_cpu_context *ctxt) +{ + struct kvm_vcpu *vcpu = ctxt_to_vcpu(ctxt); + + if (ctxt_is_guest(ctxt) && kvm_host_owns_debug_regs(vcpu)) + return &vcpu->arch.external_mdscr_el1; + + return &ctxt_sys_reg(ctxt, MDSCR_EL1); +} + static inline void __sysreg_save_common_state(struct kvm_cpu_context *ctxt) { - ctxt_sys_reg(ctxt, MDSCR_EL1) = read_sysreg(mdscr_el1); + *ctxt_mdscr_el1(ctxt) = read_sysreg(mdscr_el1); // POR_EL0 can affect uaccess, so must be saved/restored early. if (ctxt_has_s1poe(ctxt)) @@ -33,16 +58,6 @@ static inline void __sysreg_save_user_state(struct kvm_cpu_context *ctxt) ctxt_sys_reg(ctxt, TPIDRRO_EL0) = read_sysreg(tpidrro_el0); } -static inline struct kvm_vcpu *ctxt_to_vcpu(struct kvm_cpu_context *ctxt) -{ - struct kvm_vcpu *vcpu = ctxt->__hyp_running_vcpu; - - if (!vcpu) - vcpu = container_of(ctxt, struct kvm_vcpu, arch.ctxt); - - return vcpu; -} - static inline bool ctxt_has_mte(struct kvm_cpu_context *ctxt) { struct kvm_vcpu *vcpu = ctxt_to_vcpu(ctxt); @@ -139,7 +154,7 @@ static inline void __sysreg_save_el2_return_state(struct kvm_cpu_context *ctxt) static inline void __sysreg_restore_common_state(struct kvm_cpu_context *ctxt) { - write_sysreg(ctxt_sys_reg(ctxt, MDSCR_EL1), mdscr_el1); + write_sysreg(*ctxt_mdscr_el1(ctxt), mdscr_el1); // POR_EL0 can affect uaccess, so must be saved/restored early. if (ctxt_has_s1poe(ctxt)) |