提交 6e0e0a7e 编写于 作者: Z Zelin Deng 提交者: Zheng Zengkai

KVM: x86: Update vCPU's hv_clock before back to guest when tsc_offset is adjusted

stable inclusion
from stable-5.10.65
commit c06e6ff2fcc34476eda29c5c14ca0db962f500cf
bugzilla: 182361 https://gitee.com/openeuler/kernel/issues/I4EH3U

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=c06e6ff2fcc34476eda29c5c14ca0db962f500cf

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

commit d9130a2d upstream.

When MSR_IA32_TSC_ADJUST is written by guest due to TSC ADJUST feature
especially there's a big tsc warp (like a new vCPU is hot-added into VM
which has been up for a long time), tsc_offset is added by a large value
then go back to guest. This causes system time jump as tsc_timestamp is
not adjusted in the meantime and pvclock monotonic character.
To fix this, just notify kvm to update vCPU's guest time before back to
guest.

Cc: stable@vger.kernel.org
Signed-off-by: NZelin Deng <zelin.deng@linux.alibaba.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-Id: <1619576521-81399-2-git-send-email-zelin.deng@linux.alibaba.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Acked-by: NWeilong Chen <chenweilong@huawei.com>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>
上级 3f91b80c
......@@ -3183,6 +3183,10 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
if (!msr_info->host_initiated) {
s64 adj = data - vcpu->arch.ia32_tsc_adjust_msr;
adjust_tsc_offset_guest(vcpu, adj);
/* Before back to guest, tsc_timestamp must be adjusted
* as well, otherwise guest's percpu pvclock time could jump.
*/
kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
}
vcpu->arch.ia32_tsc_adjust_msr = data;
}
......
Markdown is supported
0% .
You are about to add 0 people to the discussion. Proceed with caution.
先完成此消息的编辑!
想要评论请 注册