File 5a4fd894-1-x86-rearrange-RESTORE_ALL-to-restore... of Package xen.10696

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File 5a4fd894-1-x86-rearrange-RESTORE_ALL-to-restore-in-stack-order.patch of Package xen.10696

# Commit f85d105e27735f0e20aa30d77f03774f3ed55ae5
# Date 2018-01-05 19:57:08 +0000
# Author Andrew Cooper <andrew.cooper3@citrix.com>
# Committer Andrew Cooper <andrew.cooper3@citrix.com>
x86/entry: Rearrange RESTORE_ALL to restore register in stack order

Results in a more predictable (i.e. linear) memory access pattern.

No functional change.

This is part of XSA-254.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>

--- a/xen/include/asm-x86/asm_defns.h
+++ b/xen/include/asm-x86/asm_defns.h
@@ -244,7 +244,6 @@ static always_inline void stac(void)
  * @compat: R8-R15 don't need reloading
  */
 .macro RESTORE_ALL adj=0 compat=0
-        LOAD_C_CLOBBERED \compat
 .if !\compat
         movq  UREGS_r15(%rsp),%r15
         movq  UREGS_r14(%rsp),%r14
@@ -253,6 +252,7 @@ static always_inline void stac(void)
 .endif
         movq  UREGS_rbp(%rsp),%rbp
         movq  UREGS_rbx(%rsp),%rbx
+        LOAD_C_CLOBBERED \compat
         subq  $-(UREGS_error_code-UREGS_r15+\adj), %rsp
 .endm

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File 5a4fd894-1-x86-rearrange-RESTORE_ALL-to-restore-in-stack-order.patch of Package xen.10696

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