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mn10300: Fix crash just after starting userspace on !CONFIG_PREEMPT

The mn10300 kernel crashes just after starting userspace programs, if
CONFIG_PREEMPT is disabled:

  Freeing unused kernel memory: 96K (90286000 - 9029e000)
  MISALIGN: 97c33ff9: unsupported instruction f
  MISALIGN: 97c33ff9: unsupported instruction f
  MISALIGN: 97c33ff9: unsupported instruction f
  :

This fixes the problem that was introduced by commit d17fc238ac14
("MN10300: Enable IRQs more in system call exit work path").

Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Akira Takeuchi 11 years ago
parent
commit
3da06ed736
1 changed files with 4 additions and 2 deletions
  1. 4 2
      arch/mn10300/kernel/entry.S

+ 4 - 2
arch/mn10300/kernel/entry.S

@@ -171,10 +171,10 @@ ret_from_intr:
 	mov	(REG_EPSW,fp),d0	# need to deliver signals before
 					# returning to userspace
 	and	EPSW_nSL,d0
-	beq	resume_kernel		# returning to supervisor mode
+	bne	resume_userspace	# returning to userspace
 
 #ifdef CONFIG_PREEMPT
-ENTRY(resume_kernel)
+resume_kernel:
 	LOCAL_IRQ_DISABLE
 	mov	(TI_preempt_count,a2),d0	# non-zero preempt_count ?
 	cmp	0,d0
@@ -189,6 +189,8 @@ need_resched:
 	bne	restore_all
 	call	preempt_schedule_irq[],0
 	jmp	need_resched
+#else
+	jmp	resume_kernel
 #endif