diff options
| author | Nicolas Pitre <nico@cam.org> | 2006-08-18 17:20:15 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2006-08-18 17:20:15 +0100 |
| commit | ba9b5d76372dc290b6ca04dad93927a22c2ac49a (patch) | |
| tree | da57578e06ded3b2384b4b2a53f32068b592bab1 /arch | |
| parent | 90af774ab150b97c0aa8ed0375f4652be986bdce (diff) | |
[ARM] 3746/2: Userspace helpers must be Thumb mode interworkable
Patch from Nicolas Pitre
The userspace helpers in clean/arch/arm/kernel/entry-armv.S are called
directly in/from userspace. They need to cope with being called from
Thumb code.
Patch below uses the bx interworking instruction when
CONFIG_ARM_THUMB=y.
Based on an earlier patch from Paul Brook <paul@codesourcery.com>
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm/kernel/entry-armv.S | 21 |
1 files changed, 12 insertions, 9 deletions
diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S index 7ea5f01dfc7..de4e3313790 100644 --- a/arch/arm/kernel/entry-armv.S +++ b/arch/arm/kernel/entry-armv.S @@ -634,6 +634,14 @@ ENTRY(__switch_to) * purpose. */ + .macro usr_ret, reg +#ifdef CONFIG_ARM_THUMB + bx \reg +#else + mov pc, \reg +#endif + .endm + .align 5 .globl __kuser_helper_start __kuser_helper_start: @@ -675,7 +683,7 @@ __kuser_memory_barrier: @ 0xffff0fa0 #if __LINUX_ARM_ARCH__ >= 6 && defined(CONFIG_SMP) mcr p15, 0, r0, c7, c10, 5 @ dmb #endif - mov pc, lr + usr_ret lr .align 5 @@ -778,7 +786,7 @@ __kuser_cmpxchg: @ 0xffff0fc0 mov r0, #-1 adds r0, r0, #0 #endif - mov pc, lr + usr_ret lr #else @@ -792,7 +800,7 @@ __kuser_cmpxchg: @ 0xffff0fc0 #ifdef CONFIG_SMP mcr p15, 0, r0, c7, c10, 5 @ dmb #endif - mov pc, lr + usr_ret lr #endif @@ -834,16 +842,11 @@ __kuser_cmpxchg: @ 0xffff0fc0 __kuser_get_tls: @ 0xffff0fe0 #if !defined(CONFIG_HAS_TLS_REG) && !defined(CONFIG_TLS_REG_EMUL) - ldr r0, [pc, #(16 - 8)] @ TLS stored at 0xffff0ff0 - mov pc, lr - #else - mrc p15, 0, r0, c13, c0, 3 @ read TLS register - mov pc, lr - #endif + usr_ret lr .rep 5 .word 0 @ pad up to __kuser_helper_version |