[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Xen-devel] [PATCH] x86/vvmx: virtualize x2APIC mode and APIC accesses can't both be enabled



According to the Intel SDM, "virtualize x2APIC mode" and "virtualize
APIC accesses" can't be enabled at the same time, or else a
vm{launch/entry} failure will happen. This was seen when running Xen
nested and with x2APIC enabled:

Dec 23 20:06:54.444025 (XEN) d3v0 VMLAUNCH error: 0x7
[...]
Dec 23 20:08:33.004078 (XEN) *** Control State ***
Dec 23 20:08:33.004086 (XEN) PinBased=0000003f CPUBased=b6a075fe 
SecondaryExec=000014fb
[...]

Fix this by making sure nvmx_update_secondary_exec_control clears the
incompatible bits from the host vmcs before merging it with the nested
vmcs.

This fixes a regression reported by osstest in the
test-amd64-amd64-qemuu-nested-intel job.

Signed-off-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>
---
 xen/arch/x86/hvm/vmx/vvmx.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/xen/arch/x86/hvm/vmx/vvmx.c b/xen/arch/x86/hvm/vmx/vvmx.c
index 5dd00e11b5..d8ab167d62 100644
--- a/xen/arch/x86/hvm/vmx/vvmx.c
+++ b/xen/arch/x86/hvm/vmx/vvmx.c
@@ -594,6 +594,7 @@ void nvmx_update_secondary_exec_control(struct vcpu *v,
     u32 shadow_cntrl;
     struct nestedvmx *nvmx = &vcpu_2_nvmx(v);
     u32 apicv_bit = SECONDARY_EXEC_APIC_REGISTER_VIRT |
+                    SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE |
                     SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY;
 
     host_cntrl &= ~apicv_bit;
-- 
2.24.1


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel

 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.