On Thu, 28 Dec 2017 13:54:18 +0800 Dongjiu Geng <gengdongjiu@xxxxxxxxxx> wrote: > Add SIGBUS signal handler. In this handler, it checks the SIGBUS type, > translates the host VA which is delivered by host to guest PA, then fill > this PA to CPER and fill the CPER to guest APEI GHES memory, finally > notify guest according to the SIGBUS type. There are two kinds of SIGBUS > that QEMU needs to handle, which are BUS_MCEERR_AO and BUS_MCEERR_AR. > > If guest accesses the poisoned memory, it generates Synchronous External > Abort(SEA). Then host kernel gets an APEI notification and call memory_failure() > to unmapped the affected page from the guest's stage2, and SIGBUS_MCEERR_AO s/unmapped/unmap/ > is delivered to Qemu's main thread. If Qemu receives this SIGBUS, it will > create a new CPER and add it to guest APEI GHES memory, then notify the > guest with a GPIO-Signal notification. too long sentence, it's hard get what goes on here, pls split it in simple sentences/rephrase so it would be easy to understand behavior. > > When guest hits a PG_hwpoison page, it will trap to KVM as stage2 fault, then a > SIGBUS_MCEERR_AR synchronous signal is delivered to Qemu, Qemu record this error > into guest APEI GHES memory and notify guest using Synchronous-External-Abort(SEA). > > Suggested-by: James Morse <james.morse@xxxxxxx> > Signed-off-by: Dongjiu Geng <gengdongjiu@xxxxxxxxxx> > --- > Address James's comments to record CPER and notify guest for SIGBUS signal handling. > Shown some discussion in [1]. > > [1]: > https://lkml.org/lkml/2017/2/27/246 > https://lkml.org/lkml/2017/9/14/241 > https://lkml.org/lkml/2017/9/22/499 > --- > include/sysemu/kvm.h | 2 +- > target/arm/kvm.c | 2 ++ > target/arm/kvm64.c | 34 ++++++++++++++++++++++++++++++++++ > 3 files changed, 37 insertions(+), 1 deletion(-) > > diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h > index 3a458f5..90c1605 100644 > --- a/include/sysemu/kvm.h > +++ b/include/sysemu/kvm.h > @@ -361,7 +361,7 @@ bool kvm_vcpu_id_is_valid(int vcpu_id); > /* Returns VCPU ID to be used on KVM_CREATE_VCPU ioctl() */ > unsigned long kvm_arch_vcpu_id(CPUState *cpu); > > -#ifdef TARGET_I386 > +#if defined(TARGET_I386) || defined(TARGET_AARCH64) > #define KVM_HAVE_MCE_INJECTION 1 > void kvm_arch_on_sigbus_vcpu(CPUState *cpu, int code, void *addr); > #endif > diff --git a/target/arm/kvm.c b/target/arm/kvm.c > index 7c17f0d..9d25f51 100644 > --- a/target/arm/kvm.c > +++ b/target/arm/kvm.c > @@ -26,6 +26,7 @@ > #include "exec/address-spaces.h" > #include "hw/boards.h" > #include "qemu/log.h" > +#include "exec/ram_addr.h" > > const KVMCapabilityInfo kvm_arch_required_capabilities[] = { > KVM_CAP_LAST_INFO > @@ -182,6 +183,7 @@ int kvm_arch_init(MachineState *ms, KVMState *s) > > cap_has_mp_state = kvm_check_extension(s, KVM_CAP_MP_STATE); > > + qemu_register_reset(kvm_unpoison_all, NULL); > type_register_static(&host_arm_cpu_type_info); > > return 0; > diff --git a/target/arm/kvm64.c b/target/arm/kvm64.c > index c00450d..6955d85 100644 > --- a/target/arm/kvm64.c > +++ b/target/arm/kvm64.c > @@ -27,6 +27,9 @@ > #include "kvm_arm.h" > #include "internals.h" > #include "hw/arm/arm.h" > +#include "exec/ram_addr.h" > +#include "hw/acpi/acpi-defs.h" > +#include "hw/acpi/hest_ghes.h" > > static bool have_guest_debug; > > @@ -944,6 +947,37 @@ int kvm_arch_get_registers(CPUState *cs) > return ret; > } > > +void kvm_arch_on_sigbus_vcpu(CPUState *c, int code, void *addr) > +{ > + ram_addr_t ram_addr; > + hwaddr paddr; > + > + assert(code == BUS_MCEERR_AR || code == BUS_MCEERR_AO); > + if (addr) { > + ram_addr = qemu_ram_addr_from_host(addr); > + if (ram_addr != RAM_ADDR_INVALID && > + kvm_physical_memory_addr_from_host(c->kvm_state, addr, &paddr)) { > + kvm_hwpoison_page_add(ram_addr); > + if (code == BUS_MCEERR_AR) { > + kvm_cpu_synchronize_state(c); > + ghes_record_errors(ACPI_HEST_NOTIFY_SEA, paddr); > + kvm_inject_arm_sea(c); > + } else if (code == BUS_MCEERR_AO) { > + ghes_record_errors(ACPI_HEST_NOTIFY_GPIO, paddr); > + qemu_hardware_error_notify(); > + } > + return; > + } > + fprintf(stderr, "Hardware memory error for memory used by " > + "QEMU itself instead of guest system!\n"); not quite sure what above message means, also fprintf() probably shouldn't be used by new code. > + } > + > + if (code == BUS_MCEERR_AR) { > + fprintf(stderr, "Hardware memory error!\n"); > + exit(1); > + } > +} > + > /* C6.6.29 BRK instruction */ > static const uint32_t brk_insn = 0xd4200000; >
