• Radim Krčmář's avatar
    x86: vdso: fix pvclock races with task migration · 80f7fdb1
    Radim Krčmář authored
    If we were migrated right after __getcpu, but before reading the
    migration_count, we wouldn't notice that we read TSC of a different
    VCPU, nor that KVM's bug made pvti invalid, as only migration_count
    on source VCPU is increased.
    
    Change vdso instead of updating migration_count on destination.
    
    Cc: stable@vger.kernel.org
    Signed-off-by: default avatarRadim Krčmář <rkrcmar@redhat.com>
    Fixes: 0a4e6be9 ("x86: kvm: Revert "remove sched notifier for cross-cpu migrations"")
    Message-Id: <1428000263-11892-1-git-send-email-rkrcmar@redhat.com>
    Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
    80f7fdb1
vclock_gettime.c 8.22 KB