diff mbox series

[5/9] x86/entry: Adjust restore_all_xen to hold stack_end in %r14

Message ID 20230915150038.602577-6-andrew.cooper3@citrix.com (mailing list archive)
State New, archived
Headers show
Series x86/spec-ctrl: AMD DIV fix, and VERW prerequisite bugfixes | expand

Commit Message

Andrew Cooper Sept. 15, 2023, 3 p.m. UTC 
All other SPEC_CTRL_{ENTRY,EXIT}_* helpers hold stack_end in %r14.  Adjust it
for consistency.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
---
CC: Jan Beulich <JBeulich@suse.com>
CC: Roger Pau Monné <roger.pau@citrix.com>
CC: Wei Liu <wl@xen.org>
---
 xen/arch/x86/include/asm/spec_ctrl_asm.h | 8 ++++----
 xen/arch/x86/x86_64/entry.S              | 8 ++++----
 2 files changed, 8 insertions(+), 8 deletions(-)
diff mbox series

Patch

diff --git a/xen/arch/x86/include/asm/spec_ctrl_asm.h b/xen/arch/x86/include/asm/spec_ctrl_asm.h
index 8996fe3fc0ef..b696033240e4 100644
--- a/xen/arch/x86/include/asm/spec_ctrl_asm.h
+++ b/xen/arch/x86/include/asm/spec_ctrl_asm.h
@@ -345,10 +345,10 @@  UNLIKELY_DISPATCH_LABEL(\@_serialise):
  */
 .macro SPEC_CTRL_EXIT_TO_XEN
 /*
- * Requires %rbx=stack_end
+ * Requires %r14=stack_end
  * Clobbers %rax, %rcx, %rdx
  */
-    testb $SCF_ist_sc_msr, STACK_CPUINFO_FIELD(spec_ctrl_flags)(%rbx)
+    testb $SCF_ist_sc_msr, STACK_CPUINFO_FIELD(spec_ctrl_flags)(%r14)
     jz .L\@_skip_sc_msr
 
     /*
@@ -359,10 +359,10 @@  UNLIKELY_DISPATCH_LABEL(\@_serialise):
      */
     xor %edx, %edx
 
-    testb $SCF_use_shadow, STACK_CPUINFO_FIELD(spec_ctrl_flags)(%rbx)
+    testb $SCF_use_shadow, STACK_CPUINFO_FIELD(spec_ctrl_flags)(%r14)
     jz .L\@_skip_sc_msr
 
-    mov STACK_CPUINFO_FIELD(shadow_spec_ctrl)(%rbx), %eax
+    mov STACK_CPUINFO_FIELD(shadow_spec_ctrl)(%r14), %eax
     mov $MSR_SPEC_CTRL, %ecx
     wrmsr
 
diff --git a/xen/arch/x86/x86_64/entry.S b/xen/arch/x86/x86_64/entry.S
index a1c860f56949..525877e97330 100644
--- a/xen/arch/x86/x86_64/entry.S
+++ b/xen/arch/x86/x86_64/entry.S
@@ -665,15 +665,15 @@  restore_all_xen:
          * Check whether we need to switch to the per-CPU page tables, in
          * case we return to late PV exit code (from an NMI or #MC).
          */
-        GET_STACK_END(bx)
-        cmpb  $0, STACK_CPUINFO_FIELD(use_pv_cr3)(%rbx)
+        GET_STACK_END(14)
+        cmpb  $0, STACK_CPUINFO_FIELD(use_pv_cr3)(%r14)
 UNLIKELY_START(ne, exit_cr3)
-        mov   STACK_CPUINFO_FIELD(pv_cr3)(%rbx), %rax
+        mov   STACK_CPUINFO_FIELD(pv_cr3)(%r14), %rax
         mov   %rax, %cr3
 UNLIKELY_END(exit_cr3)
 
         /* WARNING! `ret`, `call *`, `jmp *` not safe beyond this point. */
-        SPEC_CTRL_EXIT_TO_XEN     /* Req: %rbx=end, Clob: acd */
+        SPEC_CTRL_EXIT_TO_XEN     /* Req: %r14=end, Clob: acd */
 
         RESTORE_ALL adj=8
         iretq