ARM: entry: allow ARM-private syscalls to be restarted

System calls will only be restarted after signal handling if they (a)
return an error code indicating that a restart is required and (b) have
`why' set to a non-zero value, to indicate that the signal interrupted
them.

This patch leaves `why' set to a non-zero value for ARM-private syscalls
, and only zeroes it for syscalls that are not implemented.

Signed-off-by: Will Deacon <will.deacon@arm.com>

diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S
index 94104bf69719f896e51836ca8a048077086fbb0a..74ad15d1a065fba97aac1d4ac43ff33a9e994470 100644 (file)
--- a/arch/arm/kernel/entry-common.S
+++ b/arch/arm/kernel/entry-common.S
@@ -442,10 +442,10 @@ local_restart:
        ldrcc   pc, [tbl, scno, lsl #2]         @ call sys_* routine
 
        add     r1, sp, #S_OFF
-2:     mov     why, #0                         @ no longer a real syscall
        cmp     scno, #(__ARM_NR_BASE - __NR_SYSCALL_BASE)
        eor     r0, scno, #__NR_SYSCALL_BASE    @ put OS number back
-       bcs     arm_syscall     
+       bcs     arm_syscall
+2:     mov     why, #0                         @ no longer a real syscall
        b       sys_ni_syscall                  @ not private func
 
 #if defined(CONFIG_OABI_COMPAT) || !defined(CONFIG_AEABI)