Commit a16fc07e authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

cpus: reorganize signal handling code 



Move the KVM "eat signals" code under CONFIG_LINUX, in preparation
for moving it to kvm-all.c; reraise non-MCE SIGBUS immediately,
without passing it to KVM.

Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 20e0ff59

cpus.c

+32 −31
Original line number Diff line number Diff line
@@ -922,6 +922,10 @@ static void sigbus_reraise(void) 


static void sigbus_handler(int n, siginfo_t *siginfo, void *ctx)

{

    if (siginfo->si_code != BUS_MCEERR_AO && siginfo->si_code != BUS_MCEERR_AR) {

        sigbus_reraise();

    }



    if (kvm_on_sigbus(siginfo->si_code, siginfo->si_addr)) {

        sigbus_reraise();

    }
@@ -939,6 +943,30 @@ static void qemu_init_sigbus(void) 
    prctl(PR_MCE_KILL, PR_MCE_KILL_SET, PR_MCE_KILL_EARLY, 0, 0);

}



static void dummy_signal(int sig)

{

}



static void qemu_kvm_init_cpu_signals(CPUState *cpu)

{

    int r;

    sigset_t set;

    struct sigaction sigact;



    memset(&sigact, 0, sizeof(sigact));

    sigact.sa_handler = dummy_signal;

    sigaction(SIG_IPI, &sigact, NULL);



    pthread_sigmask(SIG_BLOCK, NULL, &set);

    sigdelset(&set, SIG_IPI);

    sigdelset(&set, SIGBUS);

    r = kvm_set_signal_mask(cpu, &set);

    if (r) {

        fprintf(stderr, "kvm_set_signal_mask: %s\n", strerror(-r));

        exit(1);

    }

}



static void qemu_kvm_eat_signals(CPUState *cpu)

{

    struct timespec ts = { 0, 0 };
@@ -960,6 +988,9 @@ static void qemu_kvm_eat_signals(CPUState *cpu) 


        switch (r) {

        case SIGBUS:

            if (siginfo.si_code != BUS_MCEERR_AO && siginfo.si_code != BUS_MCEERR_AR) {

                sigbus_reraise();

            }

            if (kvm_on_sigbus_vcpu(cpu, siginfo.si_code, siginfo.si_addr)) {

                sigbus_reraise();

            }
@@ -975,9 +1006,7 @@ static void qemu_kvm_eat_signals(CPUState *cpu) 
        }

    } while (sigismember(&chkset, SIG_IPI) || sigismember(&chkset, SIGBUS));

}



#else /* !CONFIG_LINUX */



static void qemu_init_sigbus(void)

{

}
@@ -985,39 +1014,11 @@ static void qemu_init_sigbus(void) 
static void qemu_kvm_eat_signals(CPUState *cpu)

{

}

#endif /* !CONFIG_LINUX */



#ifndef _WIN32

static void dummy_signal(int sig)

{

}



static void qemu_kvm_init_cpu_signals(CPUState *cpu)

{

    int r;

    sigset_t set;

    struct sigaction sigact;



    memset(&sigact, 0, sizeof(sigact));

    sigact.sa_handler = dummy_signal;

    sigaction(SIG_IPI, &sigact, NULL);



    pthread_sigmask(SIG_BLOCK, NULL, &set);

    sigdelset(&set, SIG_IPI);

    sigdelset(&set, SIGBUS);

    r = kvm_set_signal_mask(cpu, &set);

    if (r) {

        fprintf(stderr, "kvm_set_signal_mask: %s\n", strerror(-r));

        exit(1);

    }

}



#else /* _WIN32 */

static void qemu_kvm_init_cpu_signals(CPUState *cpu)

{

    abort();

}

#endif /* _WIN32 */

#endif /* !CONFIG_LINUX */



static QemuMutex qemu_global_mutex;

include/qemu/osdep.h

+9 −0
Original line number Diff line number Diff line
@@ -284,6 +284,15 @@ void qemu_anon_ram_free(void *ptr, size_t size); 


#endif



#if defined(CONFIG_LINUX)

#ifndef BUS_MCEERR_AR

#define BUS_MCEERR_AR 4

#endif

#ifndef BUS_MCEERR_AO

#define BUS_MCEERR_AO 5

#endif

#endif



#if defined(__linux__) && \

    (defined(__x86_64__) || defined(__arm__) || defined(__aarch64__))

   /* Use 2 MiB alignment so transparent hugepages can be used by KVM.

target/i386/kvm.c

+2 −13
Original line number Diff line number Diff line
@@ -64,13 +64,6 @@ 
 * 255 kvm_msr_entry structs */

#define MSR_BUF_SIZE 4096



#ifndef BUS_MCEERR_AR

#define BUS_MCEERR_AR 4

#endif

#ifndef BUS_MCEERR_AO

#define BUS_MCEERR_AO 5

#endif



const KVMCapabilityInfo kvm_arch_required_capabilities[] = {

    KVM_CAP_INFO(SET_TSS_ADDR),

    KVM_CAP_INFO(EXT_CPUID),
@@ -469,9 +462,7 @@ int kvm_arch_on_sigbus_vcpu(CPUState *c, int code, void *addr) 
    ram_addr_t ram_addr;

    hwaddr paddr;



    if (code != BUS_MCEERR_AR && code != BUS_MCEERR_AO) {

        return 1;

    }

    assert(code == BUS_MCEERR_AR || code == BUS_MCEERR_AO);



    /* Because the MCE happened while running the VCPU, KVM could have

     * injected action required MCEs too.  Action optional MCEs should
@@ -504,9 +495,7 @@ int kvm_arch_on_sigbus(int code, void *addr) 
{

    X86CPU *cpu = X86_CPU(first_cpu);



    if (code != BUS_MCEERR_AR && code != BUS_MCEERR_AO) {

        return 1;

    }

    assert(code == BUS_MCEERR_AR || code == BUS_MCEERR_AO);



    if (code == BUS_MCEERR_AR) {

        hardware_memory_error();