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-rw-r--r--arch/x86/lib/copy_user_64.S7
-rw-r--r--arch/x86/lib/msr-reg.S8
-rw-r--r--arch/x86/lib/x86-opcode-map.txt2
3 files changed, 10 insertions, 7 deletions
diff --git a/arch/x86/lib/copy_user_64.S b/arch/x86/lib/copy_user_64.S
index c5959576c315..020f75cc8cf6 100644
--- a/arch/x86/lib/copy_user_64.S
+++ b/arch/x86/lib/copy_user_64.S
@@ -37,7 +37,7 @@ ENTRY(copy_user_generic_unrolled)
movl %edx,%ecx
andl $63,%edx
shrl $6,%ecx
- jz 17f
+ jz .L_copy_short_string
1: movq (%rsi),%r8
2: movq 1*8(%rsi),%r9
3: movq 2*8(%rsi),%r10
@@ -58,7 +58,8 @@ ENTRY(copy_user_generic_unrolled)
leaq 64(%rdi),%rdi
decl %ecx
jnz 1b
-17: movl %edx,%ecx
+.L_copy_short_string:
+ movl %edx,%ecx
andl $7,%edx
shrl $3,%ecx
jz 20f
@@ -174,6 +175,8 @@ EXPORT_SYMBOL(copy_user_generic_string)
*/
ENTRY(copy_user_enhanced_fast_string)
ASM_STAC
+ cmpl $64,%edx
+ jb .L_copy_short_string /* less then 64 bytes, avoid the costly 'rep' */
movl %edx,%ecx
1: rep
movsb
diff --git a/arch/x86/lib/msr-reg.S b/arch/x86/lib/msr-reg.S
index c81556409bbb..10ffa7e8519f 100644
--- a/arch/x86/lib/msr-reg.S
+++ b/arch/x86/lib/msr-reg.S
@@ -13,14 +13,14 @@
.macro op_safe_regs op
ENTRY(\op\()_safe_regs)
pushq %rbx
- pushq %rbp
+ pushq %r12
movq %rdi, %r10 /* Save pointer */
xorl %r11d, %r11d /* Return value */
movl (%rdi), %eax
movl 4(%rdi), %ecx
movl 8(%rdi), %edx
movl 12(%rdi), %ebx
- movl 20(%rdi), %ebp
+ movl 20(%rdi), %r12d
movl 24(%rdi), %esi
movl 28(%rdi), %edi
1: \op
@@ -29,10 +29,10 @@ ENTRY(\op\()_safe_regs)
movl %ecx, 4(%r10)
movl %edx, 8(%r10)
movl %ebx, 12(%r10)
- movl %ebp, 20(%r10)
+ movl %r12d, 20(%r10)
movl %esi, 24(%r10)
movl %edi, 28(%r10)
- popq %rbp
+ popq %r12
popq %rbx
ret
3:
diff --git a/arch/x86/lib/x86-opcode-map.txt b/arch/x86/lib/x86-opcode-map.txt
index 767be7c76034..12e377184ee4 100644
--- a/arch/x86/lib/x86-opcode-map.txt
+++ b/arch/x86/lib/x86-opcode-map.txt
@@ -1009,7 +1009,7 @@ GrpTable: Grp15
1: fxstor | RDGSBASE Ry (F3),(11B)
2: vldmxcsr Md (v1) | WRFSBASE Ry (F3),(11B)
3: vstmxcsr Md (v1) | WRGSBASE Ry (F3),(11B)
-4: XSAVE
+4: XSAVE | ptwrite Ey (F3),(11B)
5: XRSTOR | lfence (11B)
6: XSAVEOPT | clwb (66) | mfence (11B)
7: clflush | clflushopt (66) | sfence (11B)