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Diffstat (limited to 'arch/arm64/lib/copy_to_user.S')
-rw-r--r--arch/arm64/lib/copy_to_user.S25
1 files changed, 19 insertions, 6 deletions
diff --git a/arch/arm64/lib/copy_to_user.S b/arch/arm64/lib/copy_to_user.S
index a0aeeb9b7a28..a257b47e2dc4 100644
--- a/arch/arm64/lib/copy_to_user.S
+++ b/arch/arm64/lib/copy_to_user.S
@@ -15,7 +15,11 @@
*/
#include <linux/linkage.h>
+
+#include <asm/alternative.h>
#include <asm/assembler.h>
+#include <asm/cpufeature.h>
+#include <asm/sysreg.h>
/*
* Copy to user space from a kernel buffer (alignment handled by the hardware)
@@ -28,14 +32,21 @@
* x0 - bytes not copied
*/
ENTRY(__copy_to_user)
- add x4, x0, x2 // upper user buffer boundary
- subs x2, x2, #8
+ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(0)), ARM64_HAS_PAN, \
+ CONFIG_ARM64_PAN)
+ add x5, x0, x2 // upper user buffer boundary
+ subs x2, x2, #16
+ b.mi 1f
+0:
+ ldp x3, x4, [x1], #16
+ subs x2, x2, #16
+USER(9f, stp x3, x4, [x0], #16)
+ b.pl 0b
+1: adds x2, x2, #8
b.mi 2f
-1:
ldr x3, [x1], #8
- subs x2, x2, #8
+ sub x2, x2, #8
USER(9f, str x3, [x0], #8 )
- b.pl 1b
2: adds x2, x2, #4
b.mi 3f
ldr w3, [x1], #4
@@ -51,11 +62,13 @@ USER(9f, strh w3, [x0], #2 )
ldrb w3, [x1]
USER(9f, strb w3, [x0] )
5: mov x0, #0
+ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(1)), ARM64_HAS_PAN, \
+ CONFIG_ARM64_PAN)
ret
ENDPROC(__copy_to_user)
.section .fixup,"ax"
.align 2
-9: sub x0, x4, x0 // bytes not copied
+9: sub x0, x5, x0 // bytes not copied
ret
.previous