lkml.org 
[lkml]   [2009]   [Dec]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    Subject[033/151] KVM: x86: include pvclock MSRs in msrs_to_save
    2.6.32-stable review patch.  If anyone has any objections, please let us know.

    ------------------

    From: Glauber Costa <glommer@redhat.com>

    commit e3267cbbbfbcbe9c18833e89b10beabb1117cb55 upstream.

    For a while now, we are issuing a rdmsr instruction to find out which
    msrs in our save list are really supported by the underlying machine.
    However, it fails to account for kvm-specific msrs, such as the pvclock
    ones.

    This patch moves then to the beginning of the list, and skip testing them.

    Signed-off-by: Glauber Costa <glommer@redhat.com>
    Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
    Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

    ---
    arch/x86/kvm/x86.c | 12 ++++++++----
    1 file changed, 8 insertions(+), 4 deletions(-)

    --- a/arch/x86/kvm/x86.c
    +++ b/arch/x86/kvm/x86.c
    @@ -484,16 +484,19 @@ static inline u32 bit(int bitno)
    * and KVM_SET_MSRS, and KVM_GET_MSR_INDEX_LIST.
    *
    * This list is modified at module load time to reflect the
    - * capabilities of the host cpu.
    + * capabilities of the host cpu. This capabilities test skips MSRs that are
    + * kvm-specific. Those are put in the beginning of the list.
    */
    +
    +#define KVM_SAVE_MSRS_BEGIN 2
    static u32 msrs_to_save[] = {
    + MSR_KVM_SYSTEM_TIME, MSR_KVM_WALL_CLOCK,
    MSR_IA32_SYSENTER_CS, MSR_IA32_SYSENTER_ESP, MSR_IA32_SYSENTER_EIP,
    MSR_K6_STAR,
    #ifdef CONFIG_X86_64
    MSR_CSTAR, MSR_KERNEL_GS_BASE, MSR_SYSCALL_MASK, MSR_LSTAR,
    #endif
    - MSR_IA32_TSC, MSR_KVM_SYSTEM_TIME, MSR_KVM_WALL_CLOCK,
    - MSR_IA32_PERF_STATUS, MSR_IA32_CR_PAT, MSR_VM_HSAVE_PA
    + MSR_IA32_TSC, MSR_IA32_PERF_STATUS, MSR_IA32_CR_PAT, MSR_VM_HSAVE_PA
    };

    static unsigned num_msrs_to_save;
    @@ -2433,7 +2436,8 @@ static void kvm_init_msr_list(void)
    u32 dummy[2];
    unsigned i, j;

    - for (i = j = 0; i < ARRAY_SIZE(msrs_to_save); i++) {
    + /* skip the first msrs in the list. KVM-specific */
    + for (i = j = KVM_SAVE_MSRS_BEGIN; i < ARRAY_SIZE(msrs_to_save); i++) {
    if (rdmsr_safe(msrs_to_save[i], &dummy[0], &dummy[1]) < 0)
    continue;
    if (j < i)



    \
     
     \ /
      Last update: 2009-12-17 05:47    [W:4.122 / U:0.152 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site