diff mbox series

[v2,10/13] x86/mpx: Map/unmap xsave area in in read_bndcfgu()

Message ID 20241105143310.28301-11-alejandro.vallejo@cloud.com (mailing list archive)
State New
Headers show
Series x86: Address Space Isolation FPU preparations | expand

Commit Message

Alejandro Vallejo Nov. 5, 2024, 2:33 p.m. UTC 
No functional change.

Signed-off-by: Alejandro Vallejo <alejandro.vallejo@cloud.com>
---
v2:
  * s/ret/bndcfgu
---
 xen/arch/x86/xstate.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/xen/arch/x86/xstate.c b/xen/arch/x86/xstate.c
index 6db7ec2ea6a9..9ecbef760277 100644
--- a/xen/arch/x86/xstate.c
+++ b/xen/arch/x86/xstate.c
@@ -1022,9 +1022,10 @@  int handle_xsetbv(u32 index, u64 new_bv)
 
 uint64_t read_bndcfgu(void)
 {
+    uint64_t bndcfgu = 0;
     unsigned long cr0 = read_cr0();
-    struct xsave_struct *xstate
-        = idle_vcpu[smp_processor_id()]->arch.xsave_area;
+    struct vcpu *v = idle_vcpu[smp_processor_id()];
+    struct xsave_struct *xstate = VCPU_MAP_XSAVE_AREA(v);
     const struct xstate_bndcsr *bndcsr;
 
     ASSERT(cpu_has_mpx);
@@ -1050,7 +1051,12 @@  uint64_t read_bndcfgu(void)
     if ( cr0 & X86_CR0_TS )
         write_cr0(cr0);
 
-    return xstate->xsave_hdr.xstate_bv & X86_XCR0_BNDCSR ? bndcsr->bndcfgu : 0;
+    if ( xstate->xsave_hdr.xstate_bv & X86_XCR0_BNDCSR )
+        bndcfgu = bndcsr->bndcfgu;
+
+    VCPU_UNMAP_XSAVE_AREA(v, xstate);
+
+    return bndcfgu;
 }
 
 void xstate_set_init(uint64_t mask)