| Message ID | 20171213150945.24054-2-vkuznets@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, 13 Dec 2017, Vitaly Kuznetsov wrote: > In hyperv_init() we presume we always have access to VP index and hypercall > MSRs while according to the specification we should check if we're allowed > to access the corresponding MSRs before accessing them. > > Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> > --- > arch/x86/hyperv/hv_init.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c > index 189a398290db..21f9d53d9f00 100644 > --- a/arch/x86/hyperv/hv_init.c > +++ b/arch/x86/hyperv/hv_init.c > @@ -110,12 +110,19 @@ static int hv_cpu_init(unsigned int cpu) > */ > void hyperv_init(void) > { > - u64 guest_id; > + u64 guest_id, required_msrs; > union hv_x64_msr_hypercall_contents hypercall_msr; > > if (x86_hyper_type != X86_HYPER_MS_HYPERV) > return; > > + /* Absolutely required MSRs */ > + required_msrs = HV_X64_MSR_HYPERCALL_AVAILABLE | > + HV_X64_MSR_VP_INDEX_AVAILABLE; > + > + if ((ms_hyperv.features & required_msrs) != required_msrs) > + return; > + > /* Allocate percpu VP index */ > hv_vp_index = kmalloc_array(num_possible_cpus(), sizeof(*hv_vp_index), > GFP_KERNEL); > -- > 2.14.3 > >
diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c index 189a398290db..21f9d53d9f00 100644 --- a/arch/x86/hyperv/hv_init.c +++ b/arch/x86/hyperv/hv_init.c @@ -110,12 +110,19 @@ static int hv_cpu_init(unsigned int cpu) */ void hyperv_init(void) { - u64 guest_id; + u64 guest_id, required_msrs; union hv_x64_msr_hypercall_contents hypercall_msr; if (x86_hyper_type != X86_HYPER_MS_HYPERV) return; + /* Absolutely required MSRs */ + required_msrs = HV_X64_MSR_HYPERCALL_AVAILABLE | + HV_X64_MSR_VP_INDEX_AVAILABLE; + + if ((ms_hyperv.features & required_msrs) != required_msrs) + return; + /* Allocate percpu VP index */ hv_vp_index = kmalloc_array(num_possible_cpus(), sizeof(*hv_vp_index), GFP_KERNEL);
In hyperv_init() we presume we always have access to VP index and hypercall MSRs while according to the specification we should check if we're allowed to access the corresponding MSRs before accessing them. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> --- arch/x86/hyperv/hv_init.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)