Commit 1a03675d authored by Glauber Costa's avatar Glauber Costa Committed by Anthony Liguori
Browse files

v2: properly save kvm system time msr registers 



Currently, the msrs involved in setting up pvclock are not saved over
migration and/or save/restore. This patch puts their value in special
fields in our CPUState, and deal with them using vmstate.

kvm also has to account for it, by including them in the msr list
for the ioctls.

This is a backport from qemu-kvm.git

[v2: sucessfully build without kerneldir ]

Signed-off-by: default avatarGlauber Costa <glommer@redhat.com>
Signed-off-by: default avatarMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: default avatarAnthony Liguori <aliguori@us.ibm.com>
parent d96fd29c

target-i386/cpu.h

+2 −0
Original line number Diff line number Diff line
@@ -651,6 +651,8 @@ typedef struct CPUX86State { 
    target_ulong fmask;

    target_ulong kernelgsbase;

#endif

    uint64_t system_time_msr;

    uint64_t wall_clock_msr;



    uint64_t tsc;

target-i386/kvm.c

+15 −0
Original line number Diff line number Diff line
@@ -35,6 +35,9 @@ 
    do { } while (0)

#endif



#define MSR_KVM_WALL_CLOCK  0x11

#define MSR_KVM_SYSTEM_TIME 0x12



#ifdef KVM_CAP_EXT_CPUID



static struct kvm_cpuid2 *try_get_cpuid(KVMState *s, int max)
@@ -494,6 +497,9 @@ static int kvm_put_msrs(CPUState *env) 
    kvm_msr_entry_set(&msrs[n++], MSR_FMASK, env->fmask);

    kvm_msr_entry_set(&msrs[n++], MSR_LSTAR, env->lstar);

#endif

    kvm_msr_entry_set(&msrs[n++], MSR_KVM_SYSTEM_TIME,  env->system_time_msr);

    kvm_msr_entry_set(&msrs[n++], MSR_KVM_WALL_CLOCK,  env->wall_clock_msr);



    msr_data.info.nmsrs = n;



    return kvm_vcpu_ioctl(env, KVM_SET_MSRS, &msr_data);
@@ -634,6 +640,9 @@ static int kvm_get_msrs(CPUState *env) 
    msrs[n++].index = MSR_FMASK;

    msrs[n++].index = MSR_LSTAR;

#endif

    msrs[n++].index = MSR_KVM_SYSTEM_TIME;

    msrs[n++].index = MSR_KVM_WALL_CLOCK;



    msr_data.info.nmsrs = n;

    ret = kvm_vcpu_ioctl(env, KVM_GET_MSRS, &msr_data);

    if (ret < 0)
@@ -670,6 +679,12 @@ static int kvm_get_msrs(CPUState *env) 
        case MSR_IA32_TSC:

            env->tsc = msrs[i].data;

            break;

        case MSR_KVM_SYSTEM_TIME:

            env->system_time_msr = msrs[i].data;

            break;

        case MSR_KVM_WALL_CLOCK:

            env->wall_clock_msr = msrs[i].data;

            break;

        }

    }

target-i386/machine.c

+3 −0
Original line number Diff line number Diff line
@@ -461,6 +461,9 @@ static const VMStateDescription vmstate_cpu = { 
        VMSTATE_UINT64_ARRAY_V(mce_banks, CPUState, MCE_BANKS_DEF *4, 10),

        /* rdtscp */

        VMSTATE_UINT64_V(tsc_aux, CPUState, 11),

        /* KVM pvclock msr */

        VMSTATE_UINT64_V(system_time_msr, CPUState, 11),

        VMSTATE_UINT64_V(wall_clock_msr, CPUState, 11),

        VMSTATE_END_OF_LIST()

        /* The above list is not sorted /wrt version numbers, watch out! */

    }