From e8679fedd026eb3b4655af83829d9036e32c9b97 Mon Sep 17 00:00:00 2001 From: James Morse Date: Fri, 29 May 2020 15:06:56 +0000 Subject: KVM: arm64: Stop save/restoring ACTLR_EL1 KVM sets HCR_EL2.TACR via HCR_GUEST_FLAGS. This means ACTLR* accesses from the guest are always trapped, and always return the value in the sys_regs array. The guest can't change the value of these registers, so we are save restoring the reset value, which came from the host. Stop save/restoring this register. Keep the storage for this register in sys_regs[] as this is how the value is exposed to user-space, removing it would break migration. Signed-off-by: James Morse Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20200529150656.7339-4-james.morse@arm.com --- arch/arm64/kvm/hyp/sysreg-sr.c | 2 -- arch/arm64/kvm/sys_regs.c | 2 -- 2 files changed, 4 deletions(-) (limited to 'arch/arm64') diff --git a/arch/arm64/kvm/hyp/sysreg-sr.c b/arch/arm64/kvm/hyp/sysreg-sr.c index 6d2df9fe0b5d..0d60e6ee96b2 100644 --- a/arch/arm64/kvm/hyp/sysreg-sr.c +++ b/arch/arm64/kvm/hyp/sysreg-sr.c @@ -39,7 +39,6 @@ static void __hyp_text __sysreg_save_el1_state(struct kvm_cpu_context *ctxt) { ctxt->sys_regs[CSSELR_EL1] = read_sysreg(csselr_el1); ctxt->sys_regs[SCTLR_EL1] = read_sysreg_el1(SYS_SCTLR); - ctxt->sys_regs[ACTLR_EL1] = read_sysreg(actlr_el1); ctxt->sys_regs[CPACR_EL1] = read_sysreg_el1(SYS_CPACR); ctxt->sys_regs[TTBR0_EL1] = read_sysreg_el1(SYS_TTBR0); ctxt->sys_regs[TTBR1_EL1] = read_sysreg_el1(SYS_TTBR1); @@ -122,7 +121,6 @@ static void __hyp_text __sysreg_restore_el1_state(struct kvm_cpu_context *ctxt) isb(); } - write_sysreg(ctxt->sys_regs[ACTLR_EL1], actlr_el1); write_sysreg_el1(ctxt->sys_regs[CPACR_EL1], SYS_CPACR); write_sysreg_el1(ctxt->sys_regs[TTBR0_EL1], SYS_TTBR0); write_sysreg_el1(ctxt->sys_regs[TTBR1_EL1], SYS_TTBR1); diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 12f8d57a3cb8..dfb966f3863a 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -78,7 +78,6 @@ static bool __vcpu_read_sys_reg_from_cpu(int reg, u64 *val) switch (reg) { case CSSELR_EL1: *val = read_sysreg_s(SYS_CSSELR_EL1); break; case SCTLR_EL1: *val = read_sysreg_s(SYS_SCTLR_EL12); break; - case ACTLR_EL1: *val = read_sysreg_s(SYS_ACTLR_EL1); break; case CPACR_EL1: *val = read_sysreg_s(SYS_CPACR_EL12); break; case TTBR0_EL1: *val = read_sysreg_s(SYS_TTBR0_EL12); break; case TTBR1_EL1: *val = read_sysreg_s(SYS_TTBR1_EL12); break; @@ -118,7 +117,6 @@ static bool __vcpu_write_sys_reg_to_cpu(u64 val, int reg) switch (reg) { case CSSELR_EL1: write_sysreg_s(val, SYS_CSSELR_EL1); break; case SCTLR_EL1: write_sysreg_s(val, SYS_SCTLR_EL12); break; - case ACTLR_EL1: write_sysreg_s(val, SYS_ACTLR_EL1); break; case CPACR_EL1: write_sysreg_s(val, SYS_CPACR_EL12); break; case TTBR0_EL1: write_sysreg_s(val, SYS_TTBR0_EL12); break; case TTBR1_EL1: write_sysreg_s(val, SYS_TTBR1_EL12); break; -- cgit v1.2.3