[xen stable-4.11] x86/msr: fix handling of MSR_IA32_PERF_{STATUS/CTL} (again, part 2)

[patchbot@xxxxxxx]

commit 1c7d984645f9ade9b47e862b5880734ad498fea8
Author:     Jan Beulich <jbeulich@xxxxxxxx>
AuthorDate: Fri Feb 5 08:54:03 2021 +0100
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Fri Feb 5 08:54:03 2021 +0100

    x86/msr: fix handling of MSR_IA32_PERF_{STATUS/CTL} (again, part 2)
    
    X86_VENDOR_* aren't bit masks in the older trees.
    
    Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
    Reviewed-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
---
 xen/arch/x86/msr.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/xen/arch/x86/msr.c b/xen/arch/x86/msr.c
index 1afb80427c..c028fbdcf4 100644
--- a/xen/arch/x86/msr.c
+++ b/xen/arch/x86/msr.c
@@ -393,7 +393,8 @@ int guest_wrmsr(struct vcpu *v, uint32_t msr, uint64_t val)
          * a cpufreq controller dom0 which has full access.
          */
     case MSR_IA32_PERF_CTL:
-        if ( !(cp->x86_vendor & (X86_VENDOR_INTEL | X86_VENDOR_CENTAUR)) )
+        if ( cp->x86_vendor != X86_VENDOR_INTEL &&
+             cp->x86_vendor != X86_VENDOR_CENTAUR )
             goto gp_fault;
 
         if ( likely(!is_cpufreq_controller(d)) || wrmsr_safe(msr, val) == 0 )
--
generated by git-patchbot for /home/xen/git/xen.git#stable-4.11