After "ARM: signal: sigreturn_codes should be endian neutral to work in BE8" commit, thumb only platforms, like armv7m, fails to compile sigreturn_codes.S. The reason is that for such arch values '.arm' directive and arm opcodes are not allowed.
Fix conditionally enables arm opcodes only if no CONFIG_CPU_THUMBONLY defined and it uses .org instructions to keep sigreturn_codes layout.
Suggested-by: Dave Martin Dave.Martin@arm.com Signed-off-by: Victor Kamensky victor.kamensky@linaro.org Tested-by: Uwe Kleine-König u.kleine-koenig@pengutronix.de --- arch/arm/kernel/sigreturn_codes.S | 40 ++++++++++++++++++++++++++++++--------- 1 file changed, 31 insertions(+), 9 deletions(-)
diff --git a/arch/arm/kernel/sigreturn_codes.S b/arch/arm/kernel/sigreturn_codes.S index 3c5d0f2..b84d0cb 100644 --- a/arch/arm/kernel/sigreturn_codes.S +++ b/arch/arm/kernel/sigreturn_codes.S @@ -30,6 +30,27 @@ * snippets. */
+/* + * In CPU_THUMBONLY case kernel arm opcodes are not allowed. + * Note in this case codes skips those instructions but it uses .org + * directive to keep correct layout of sigreturn_codes array. + */ +#ifndef CONFIG_CPU_THUMBONLY +#define ARM_OK(code...) code +#else +#define ARM_OK(code...) +#endif + + .macro arm_slot n + .org sigreturn_codes + 12 * (\n) +ARM_OK( .arm ) + .endm + + .macro thumb_slot n + .org sigreturn_codes + 12 * (\n) + 8 + .thumb + .endm + #if __LINUX_ARM_ARCH__ <= 4 /* * Note we manually set minimally required arch that supports @@ -45,26 +66,27 @@ .global sigreturn_codes .type sigreturn_codes, #object
- .arm + .align
sigreturn_codes:
/* ARM sigreturn syscall code snippet */ - mov r7, #(__NR_sigreturn - __NR_SYSCALL_BASE) - swi #(__NR_sigreturn)|(__NR_OABI_SYSCALL_BASE) + arm_slot 0 +ARM_OK( mov r7, #(__NR_sigreturn - __NR_SYSCALL_BASE) ) +ARM_OK( swi #(__NR_sigreturn)|(__NR_OABI_SYSCALL_BASE) )
/* Thumb sigreturn syscall code snippet */ - .thumb + thumb_slot 0 movs r7, #(__NR_sigreturn - __NR_SYSCALL_BASE) swi #0
/* ARM sigreturn_rt syscall code snippet */ - .arm - mov r7, #(__NR_rt_sigreturn - __NR_SYSCALL_BASE) - swi #(__NR_rt_sigreturn)|(__NR_OABI_SYSCALL_BASE) + arm_slot 1 +ARM_OK( mov r7, #(__NR_rt_sigreturn - __NR_SYSCALL_BASE) ) +ARM_OK( swi #(__NR_rt_sigreturn)|(__NR_OABI_SYSCALL_BASE) )
/* Thumb sigreturn_rt syscall code snippet */ - .thumb + thumb_slot 1 movs r7, #(__NR_rt_sigreturn - __NR_SYSCALL_BASE) swi #0
@@ -74,7 +96,7 @@ sigreturn_codes: * it is thumb case or not, so we need additional * word after real last entry. */ - .arm + arm_slot 2 .space 4
.size sigreturn_codes, . - sigreturn_codes