When guest OS happens SError interrupt(SEI), it will trap to host. Host check the Asynchronous Error Type(ESR_ELx.AET). If it the error has not been propagated and has not (yet) been architecturally consumed by the PE, it will return to use space with error code KVM_SEI_SEV_RECOVERABLE. Qemu receive this exception exit, check whether KVM support to set ESR(exception syndrome registers) value. If support, it sets the ESR value using a new IOCTL. This handling is only supported in AArch64 platform, not supported in AArch32 platform. Signed-off-by: Dongjiu Geng <gengdongjiu@xxxxxxxxxx> Signed-off-by: Quanming Wu <wuquanming@xxxxxxxxxx> --- Address James and Marc's comments to set ESR and inject SEI by user space in [1] [1]: https://lkml.org/lkml/2017/3/20/441 https://lkml.org/lkml/2017/3/20/516 Below is the log that Qemu inject SError with specify ESR and guest happen exception: Bad mode in Error handler detected, code 0xbe000c11 -- SError CPU: 0 PID: 539 Comm: devmem Tainted: G D 4.1.0+ #20 Hardware name: linux,dummy-virt (DT) task: ffffffc019aad600 ti: ffffffc008134000 task.ti: ffffffc008134000 PC is at 0x405cc0 LR is at 0x40ce80 pc : [<0000000000405cc0>] lr : [<000000000040ce80>] pstate: 60000000 sp : ffffffc008137ff0 x29: 0000007fd9e80790 x28: 0000000000000000 x27: 00000000000000ad x26: 000000000049c000 x25: 000000000048904b x24: 000000000049c000 x23: 0000000040600000 x22: 0000007fd9e808d0 x21: 0000000000000002 x20: 0000000000000000 x19: 0000000000000020 x18: 0000000000000000 x17: 0000000000405cc0 x16: 000000000049c698 x15: 0000000000005798 x14: 0000007f93875f1c x13: 0000007f93a8ccb0 x12: 0000000000000137 x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000 x8 : 00000000000000de x7 : 0000000000000000 x6 : 0000000000002000 x5 : 0000000040600000 x4 : 0000000000000003 x3 : 0000000000000001 x2 : 00000000000f123b x1 : 0000000000000008 x0 : 000000000047a048 --- target/arm/internals.h | 4 ++++ target/arm/kvm.c | 3 +++ target/arm/kvm32.c | 6 ++++++ target/arm/kvm64.c | 34 ++++++++++++++++++++++++++++++++++ target/arm/kvm_arm.h | 8 ++++++++ 5 files changed, 55 insertions(+) diff --git a/target/arm/internals.h b/target/arm/internals.h index 1f6efef..cd26a9d 100644 --- a/target/arm/internals.h +++ b/target/arm/internals.h @@ -233,9 +233,13 @@ enum arm_exception_class { #define ARM_EL_EC_SHIFT 26 #define ARM_EL_IL_SHIFT 25 #define ARM_EL_ISV_SHIFT 24 +#define ARM_EL_AET_SHIFT 10 #define ARM_EL_IL (1 << ARM_EL_IL_SHIFT) #define ARM_EL_ISV (1 << ARM_EL_ISV_SHIFT) +/* Asynchronous Error Type */ +#define KVM_SEI_SEV_RECOVERABLE 1 + /* Utility functions for constructing various kinds of syndrome value. * Note that in general we follow the AArch64 syndrome values; in a * few cases the value in HSR for exceptions taken to AArch32 Hyp diff --git a/target/arm/kvm.c b/target/arm/kvm.c index 7c17f0d..d85e36a 100644 --- a/target/arm/kvm.c +++ b/target/arm/kvm.c @@ -593,6 +593,9 @@ int kvm_arch_handle_exit(CPUState *cs, struct kvm_run *run) ret = EXCP_DEBUG; } /* otherwise return to guest */ break; + case KVM_EXIT_EXCEPTION: + kvm_arm_handle_exception(cs, run); + break; default: qemu_log_mask(LOG_UNIMP, "%s: un-handled exit reason %d\n", __func__, run->exit_reason); diff --git a/target/arm/kvm32.c b/target/arm/kvm32.c index 069da0c..8ce56fd 100644 --- a/target/arm/kvm32.c +++ b/target/arm/kvm32.c @@ -493,6 +493,12 @@ bool kvm_arm_handle_debug(CPUState *cs, struct kvm_debug_exit_arch *debug_exit) return false; } +bool kvm_arm_handle_exception(CPUState *cs, struct kvm_run *run) +{ + qemu_log_mask(LOG_UNIMP, "%s: not implemented\n", __func__); + return false; +} + int kvm_arch_insert_hw_breakpoint(target_ulong addr, target_ulong len, int type) { diff --git a/target/arm/kvm64.c b/target/arm/kvm64.c index af8ebc9..2d0eb32 100644 --- a/target/arm/kvm64.c +++ b/target/arm/kvm64.c @@ -986,3 +986,37 @@ static bool kvm_can_set_vcpu_esr(struct KVMState *state) int ret = kvm_check_extension(state, KVM_CAP_ARM_INJECT_SERROR_ESR); return (ret) ? true : false; } + +static bool kvm_inject_arm_sei(CPUState *cs, unsigned int error_code) +{ + int ret; + /* IMPLEMENTATION DEFINED syndrome by default */ + uint32_t syndrome = ARM_EL_ISV; + + if (kvm_can_set_vcpu_esr(cs->kvm_state)) { + if (error_code == KVM_SEI_SEV_RECOVERABLE) { + /* Set Recoverable Asynchronous SError interrupt Type */ + syndrome = (3 << ARM_EL_AET_SHIFT) | 0x11; + } + ret = kvm_vcpu_ioctl(cs, KVM_ARM_INJECT_SERROR_ESR, &syndrome); + if (ret < 0) { + fprintf(stderr, "KVM_ARM_SET_SERROR_ESR failed: %s\n", + strerror(-ret)); + abort(); + } + + return true; + } + + return false; +} + +bool kvm_arm_handle_exception(CPUState *cs, struct kvm_run *run) +{ + int exception = run->ex.exception; + unsigned int error_code = run->ex.error_code; + if (exception == EC_SERROR) { + return kvm_inject_arm_sei(cs, error_code); + } + return false; +} diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h index 633d088..b2a7933 100644 --- a/target/arm/kvm_arm.h +++ b/target/arm/kvm_arm.h @@ -288,4 +288,12 @@ static inline const char *its_class_name(void) } } +/** + * kvm_arm_handle_exception: + * @cs: CPUState + * @run: KVM RUN structure + * + * Returns: TRUE if the SError exception was successfully handled + */ +bool kvm_arm_handle_exception(CPUState *cs, struct kvm_run *run); #endif -- 1.8.3.1
