From mboxrd@z Thu Jan 1 00:00:00 1970 From: julien.thierry@arm.com (Julien Thierry) Date: Wed, 15 Nov 2017 09:25:08 +0000 Subject: [PATCH 24/37] KVM: arm64: Prepare to handle traps on deferred EL0 sysregs In-Reply-To: <20171012104141.26902-25-christoffer.dall@linaro.org> References: <20171012104141.26902-1-christoffer.dall@linaro.org> <20171012104141.26902-25-christoffer.dall@linaro.org> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 12/10/17 11:41, Christoffer Dall wrote: > We can trap access to ACTLR_EL1 which we can later defer to only > save/restore during vcpu_load and vcpu_put, so let's read the value > directly from the CPU when necessary. > > Signed-off-by: Christoffer Dall > --- > arch/arm64/kvm/sys_regs_generic_v8.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/arch/arm64/kvm/sys_regs_generic_v8.c b/arch/arm64/kvm/sys_regs_generic_v8.c > index 969ade1..348f227 100644 > --- a/arch/arm64/kvm/sys_regs_generic_v8.c > +++ b/arch/arm64/kvm/sys_regs_generic_v8.c > @@ -38,7 +38,10 @@ static bool access_actlr(struct kvm_vcpu *vcpu, > if (p->is_write) > return ignore_write(vcpu, p); > > - p->regval = vcpu_sys_reg(vcpu, ACTLR_EL1); > + if (vcpu->arch.sysregs_loaded_on_cpu) > + read_sysreg(actlr_el1); Did you mean "p->regval = read_sysreg(actlr_el1);" ? > + else > + p->regval = vcpu_sys_reg(vcpu, ACTLR_EL1); > return true; > } > > -- Julien Thierry