File xsa456-0o.patch of Package xen.33138

# Commit 45dac88e78e8a2d9d8738eef884fe6730faf9e67
# Date 2024-04-09 16:37:30 +0100
# Author Andrew Cooper <andrew.cooper3@citrix.com>
# Committer Andrew Cooper <andrew.cooper3@citrix.com>
x86/spec-ctrl: Widen the {xen,last,default}_spec_ctrl fields

Right now, they're all bytes, but MSR_SPEC_CTRL has been steadily gaining new
features.

No functional change.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>

--- a/xen/arch/x86/spec_ctrl.c
+++ b/xen/arch/x86/spec_ctrl.c
@@ -66,7 +66,7 @@ bool __read_mostly opt_branch_harden = t
 static bool __initdata opt_lock_harden;
 
 bool __initdata bsp_delay_spec_ctrl;
-uint8_t __read_mostly default_xen_spec_ctrl;
+unsigned int __read_mostly default_xen_spec_ctrl;
 uint8_t __read_mostly default_scf;
 
 paddr_t __read_mostly l1tf_addr_mask, __read_mostly l1tf_safe_maddr;
--- a/xen/include/asm-x86/current.h
+++ b/xen/include/asm-x86/current.h
@@ -55,7 +55,7 @@ struct cpu_info {
 
     /* See asm-x86/spec_ctrl_asm.h for usage. */
     unsigned int shadow_spec_ctrl;
-    uint8_t      xen_spec_ctrl;
+    unsigned int xen_spec_ctrl;
     uint8_t      scf; /* SCF_* */
 
     /*
@@ -73,7 +73,7 @@ struct cpu_info {
      */
     bool         use_pv_cr3;
 
-    unsigned long __pad;
+    /* unsigned long __pad; */
     /* get_stack_bottom() must be 16-byte aligned */
 };
 
--- a/xen/include/asm-x86/spec_ctrl.h
+++ b/xen/include/asm-x86/spec_ctrl.h
@@ -94,7 +94,7 @@ extern int8_t opt_l1d_flush;
 extern bool opt_branch_harden;
 
 extern bool bsp_delay_spec_ctrl;
-extern uint8_t default_xen_spec_ctrl;
+extern unsigned int default_xen_spec_ctrl;
 extern uint8_t default_scf;
 
 extern int8_t opt_xpti_hwdom, opt_xpti_domu;
--- a/xen/include/asm-x86/spec_ctrl_asm.h
+++ b/xen/include/asm-x86/spec_ctrl_asm.h
@@ -155,7 +155,7 @@
     andb $~SCF_use_shadow, CPUINFO_scf(%rsp)
 
     /* Load Xen's intended value. */
-    movzbl CPUINFO_xen_spec_ctrl(%rsp), %eax
+    mov CPUINFO_xen_spec_ctrl(%rsp), %eax
     wrmsr
 .endm
 
@@ -224,10 +224,10 @@
         setnz %al
         not %eax
         and %al, STACK_CPUINFO_FIELD(scf)(%r14)
-        movzbl STACK_CPUINFO_FIELD(xen_spec_ctrl)(%r14), %eax
+        mov STACK_CPUINFO_FIELD(xen_spec_ctrl)(%r14), %eax
     .else
         andb $~SCF_use_shadow, CPUINFO_scf(%rsp)
-        movzbl CPUINFO_xen_spec_ctrl(%rsp), %eax
+        mov  CPUINFO_xen_spec_ctrl(%rsp), %eax
     .endif
 
     wrmsr
@@ -425,7 +425,7 @@
 
     /* Load Xen's intended value. */
     mov $MSR_SPEC_CTRL, %ecx
-    movzbl STACK_CPUINFO_FIELD(xen_spec_ctrl)(%r14), %eax
+    mov STACK_CPUINFO_FIELD(xen_spec_ctrl)(%r14), %eax
     wrmsr
 
 .L\@_skip_msr_spec_ctrl: