On 1/5/21 11:20 AM, Sean Christopherson wrote:
On Tue, Jan 05, 2021, Michael Roth wrote:
@@ -3703,16 +3688,9 @@ static noinstr void svm_vcpu_enter_exit(struct kvm_vcpu *vcpu,
if (sev_es_guest(svm->vcpu.kvm)) {
__svm_sev_es_vcpu_run(svm->vmcb_pa);
} else {
- __svm_vcpu_run(svm->vmcb_pa, (unsigned long *)&svm->vcpu.arch.regs);
-
-#ifdef CONFIG_X86_64
- native_wrmsrl(MSR_GS_BASE, svm->host.gs_base);
-#else
- loadsegment(fs, svm->host.fs);
-#ifndef CONFIG_X86_32_LAZY_GS
- loadsegment(gs, svm->host.gs);
-#endif
-#endif
+ __svm_vcpu_run(svm->vmcb_pa, (unsigned long *)&svm->vcpu.arch.regs,
+ page_to_phys(per_cpu(svm_data,
+ vcpu->cpu)->save_area));
Does this need to use __sme_page_pa()?
Yes, it should now. The SEV-ES support added the SME encryption bit to the
MSR_VM_HSAVE_PA MSR, so we need to be consistent in how the data is read
and written.
Thanks,
Tom
}
/*
...
diff --git a/arch/x86/kvm/svm/vmenter.S b/arch/x86/kvm/svm/vmenter.S
index 6feb8c08f45a..89f4e8e7bf0e 100644
--- a/arch/x86/kvm/svm/vmenter.S
+++ b/arch/x86/kvm/svm/vmenter.S
@@ -33,6 +33,7 @@
* __svm_vcpu_run - Run a vCPU via a transition to SVM guest mode
* @vmcb_pa: unsigned long
* @regs: unsigned long * (to guest registers)
+ * @hostsa_pa: unsigned long
*/
SYM_FUNC_START(__svm_vcpu_run)
push %_ASM_BP
@@ -47,6 +48,9 @@ SYM_FUNC_START(__svm_vcpu_run)
#endif
push %_ASM_BX
+ /* Save @hostsa_pa */
+ push %_ASM_ARG3
+
/* Save @regs. */
push %_ASM_ARG2
@@ -154,6 +158,12 @@ SYM_FUNC_START(__svm_vcpu_run)
xor %r15d, %r15d
#endif
+ /* "POP" @hostsa_pa to RAX. */
+ pop %_ASM_AX
+
+ /* Restore host user state and FS/GS base */
+ vmload %_ASM_AX
This VMLOAD needs the "handle fault on reboot" goo. Seeing the code, I think
I'd prefer to handle this in C code, especially if Paolo takes the svm_ops.h
patch[*]. Actually, I think with that patch it'd make sense to move the
existing VMSAVE+VMLOAD for the guest into svm.c, too. And completely unrelated,
the fault handling in svm/vmenter.S can be cleaned up a smidge to eliminate the
JMPs.
Paolo, what do you think about me folding these patches into my series to do the
above cleanups? And maybe sending a pull request for the end result? (I'd also
like to add on a patch to use the user return MSR mechanism for MSR_TSC_AUX).
[*] https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Flkml.kernel.org%2Fr%2F20201231002702.2223707-8-seanjc%40google.com&data=04%7C01%7Cthomas.lendacky%40amd.com%7C5125acb3a3384ee75a5c08d8b19e2888%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637454640159484993%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=Q%2F%2B7kxE9pcV%2BelzHbeRpvs8wlQGQkirKUPg7fBP3QbU%3D&reserved=0
+
pop %_ASM_BX
#ifdef CONFIG_X86_64
--
2.25.1
