From mboxrd@z Thu Jan 1 00:00:00 1970 From: Punit Agrawal Subject: Re: [PATCH V3 10/10] arm64: KVM: add guest SEA support Date: Thu, 13 Oct 2016 14:14:48 +0100 Message-ID: <87h98gs853.fsf@e105922-lin.cambridge.arm.com> References: <1475875882-2604-1-git-send-email-tbaicar@codeaurora.org> <1475875882-2604-11-git-send-email-tbaicar@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1475875882-2604-11-git-send-email-tbaicar@codeaurora.org> (Tyler Baicar's message of "Fri, 7 Oct 2016 15:31:22 -0600") List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu To: Tyler Baicar Cc: linux-efi@vger.kernel.org, matt@codeblueprint.co.uk, catalin.marinas@arm.com, will.deacon@arm.com, robert.moore@intel.com, paul.gortmaker@windriver.com, lv.zheng@intel.com, kvmarm@lists.cs.columbia.edu, fu.wei@linaro.org, linux@armlinux.org.uk, linux-acpi@vger.kernel.org, shijie.huang@arm.com, lenb@kernel.org, marc.zyngier@arm.com, tomasz.nowicki@linaro.org, rostedt@goodmis.org, sandeepa.s.prabhu@gmail.com, Dkvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, devel@acpica.org, rjw@rjwysocki.net, linux-kernel@vger.kernel.org, pbonzini@redhat.com, akpm@linux-foundation.org, bristot@redhat.com List-Id: linux-acpi@vger.kernel.org Hi Tyler, I know I've had my last comment already ;), but I thought I'd rather raise the question than stay confused... Tyler Baicar writes: > Currently external aborts are unsupported by the guest abort > handling. Add handling for SEAs so that the host kernel reports > SEAs which occur in the guest kernel. > > Signed-off-by: Tyler Baicar > --- > arch/arm/include/asm/kvm_arm.h | 1 + > arch/arm/include/asm/system_misc.h | 5 +++++ > arch/arm/kvm/mmu.c | 15 +++++++++++++-- > arch/arm64/include/asm/kvm_arm.h | 1 + > arch/arm64/include/asm/system_misc.h | 2 ++ > arch/arm64/mm/fault.c | 13 +++++++++++++ > 6 files changed, 35 insertions(+), 2 deletions(-) > > diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h > index e22089f..33a77509 100644 > --- a/arch/arm/include/asm/kvm_arm.h > +++ b/arch/arm/include/asm/kvm_arm.h > @@ -187,6 +187,7 @@ > #define FSC_FAULT (0x04) > #define FSC_ACCESS (0x08) > #define FSC_PERM (0x0c) > +#define FSC_EXTABT (0x10) > > /* Hyp Prefetch Fault Address Register (HPFAR/HDFAR) */ > #define HPFAR_MASK (~0xf) > diff --git a/arch/arm/include/asm/system_misc.h b/arch/arm/include/asm/system_misc.h > index a3d61ad..86e1faa 100644 > --- a/arch/arm/include/asm/system_misc.h > +++ b/arch/arm/include/asm/system_misc.h > @@ -24,4 +24,9 @@ extern unsigned int user_debug; > > #endif /* !__ASSEMBLY__ */ > > +inline int handle_guest_sea(unsigned long addr, unsigned int esr) > +{ > + return -1; > +} > + > #endif /* __ASM_ARM_SYSTEM_MISC_H */ > diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c > index e9a5c0e..24cde84 100644 > --- a/arch/arm/kvm/mmu.c > +++ b/arch/arm/kvm/mmu.c > @@ -29,6 +29,7 @@ > #include > #include > #include > +#include > > #include "trace.h" > > @@ -1441,8 +1442,18 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run) > > /* Check the stage-2 fault is trans. fault or write fault */ > fault_status = kvm_vcpu_trap_get_fault_type(vcpu); > - if (fault_status != FSC_FAULT && fault_status != FSC_PERM && > - fault_status != FSC_ACCESS) { > + > + if (fault_status == FSC_EXTABT) { > + if(handle_guest_sea((unsigned long)fault_ipa, > + kvm_vcpu_get_hsr(vcpu))) { > + kvm_err("Failed to handle guest SEA, FSC: EC=%#x xFSC=%#lx ESR_EL2=%#lx\n", > + kvm_vcpu_trap_get_class(vcpu), > + (unsigned long)kvm_vcpu_trap_get_fault(vcpu), > + (unsigned long)kvm_vcpu_get_hsr(vcpu)); > + return -EFAULT; > + } > + } else if (fault_status != FSC_FAULT && fault_status != FSC_PERM && > + fault_status != FSC_ACCESS) { > kvm_err("Unsupported FSC: EC=%#x xFSC=%#lx ESR_EL2=%#lx\n", > kvm_vcpu_trap_get_class(vcpu), > (unsigned long)kvm_vcpu_trap_get_fault(vcpu), > diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h > index 4b5c977..be0efb6 100644 > --- a/arch/arm64/include/asm/kvm_arm.h > +++ b/arch/arm64/include/asm/kvm_arm.h > @@ -201,6 +201,7 @@ > #define FSC_FAULT ESR_ELx_FSC_FAULT > #define FSC_ACCESS ESR_ELx_FSC_ACCESS > #define FSC_PERM ESR_ELx_FSC_PERM > +#define FSC_EXTABT ESR_ELx_FSC_EXTABT > > /* Hyp Prefetch Fault Address Register (HPFAR/HDFAR) */ > #define HPFAR_MASK (~UL(0xf)) > diff --git a/arch/arm64/include/asm/system_misc.h b/arch/arm64/include/asm/system_misc.h > index 90daf4a..8522fff 100644 > --- a/arch/arm64/include/asm/system_misc.h > +++ b/arch/arm64/include/asm/system_misc.h > @@ -77,4 +77,6 @@ extern void (*arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd); > int sea_register_handler_chain(struct notifier_block *nb); > void sea_unregister_handler_chain(struct notifier_block *nb); > > +int handle_guest_sea(unsigned long addr, unsigned int esr); > + > #endif /* __ASM_SYSTEM_MISC_H */ > diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c > index 81cb7ad..d714432 100644 > --- a/arch/arm64/mm/fault.c > +++ b/arch/arm64/mm/fault.c > @@ -597,6 +597,19 @@ static const char *fault_name(unsigned int esr) > } > > /* > + * Handle Synchronous External Aborts that occur in a guest kernel. > + */ > +int handle_guest_sea(unsigned long addr, unsigned int esr) > +{ > + atomic_notifier_call_chain(&sea_handler_chain, 0, NULL); > + > + pr_err("Synchronous External Abort: %s (0x%08x) at 0x%016lx\n", > + fault_name(esr), esr, addr); > + > + return 0; > +} Don't we need to pass the abort to the guest? Thanks, Punit > + > +/* > * Dispatch a data abort to the relevant handler. > */ > asmlinkage void __exception do_mem_abort(unsigned long addr, unsigned int esr,