ARM: entry: avoid enabling interrupts in prefetch/data abort handlers

Avoid enabling interrupts if the parent context had interrupts enabled
in the abort handler assembly code, and move this into the breakpoint/
page/alignment fault handlers instead.

This gets rid of some special-casing for the breakpoint fault handlers
from the low level abort handler path.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 19 insertions, 24 deletions

diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
index d644d0240ad3..c46bafa2f6dc 100644
--- a/arch/arm/kernel/entry-armv.S
+++ b/arch/arm/kernel/entry-armv.S
@@ -185,20 +185,15 @@ ENDPROC(__und_invalid)
 __dabt_svc:
         svc_entry
 
-        @
-        @ get ready to re-enable interrupts if appropriate
-        @
-        mrs     r9, cpsr
-        tst     r5, #PSR_I_BIT
-        biceq   r9, r9, #PSR_I_BIT
+#ifdef CONFIG_TRACE_IRQFLAGS
+        bl      trace_hardirqs_off
+#endif
 
         dabt_helper
 
         @
-        @ set desired IRQ state, then call main handler
+        @ call main handler
         @
-        debug_entry r1
-        msr     cpsr_c, r9
         mov     r2, sp
         bl      do_DataAbort
 
@@ -211,6 +206,12 @@ __dabt_svc:
         @ restore SPSR and restart the instruction
         @
         ldr     r5, [sp, #S_PSR]
+#ifdef CONFIG_TRACE_IRQFLAGS
+        tst     r5, #PSR_I_BIT
+        bleq    trace_hardirqs_on
+        tst     r5, #PSR_I_BIT
+        blne    trace_hardirqs_off
+#endif
         svc_exit r5                             @ return from exception
  UNWIND(.fnend          )
 ENDPROC(__dabt_svc)
@@ -307,16 +308,11 @@ ENDPROC(__und_svc)
 __pabt_svc:
         svc_entry
 
-        @
-        @ re-enable interrupts if appropriate
-        @
-        mrs     r9, cpsr
-        tst     r5, #PSR_I_BIT
-        biceq   r9, r9, #PSR_I_BIT
+#ifdef CONFIG_TRACE_IRQFLAGS
+        bl      trace_hardirqs_off
+#endif
 
         pabt_helper
-        debug_entry r1
-        msr     cpsr_c, r9                      @ Maybe enable interrupts
         mov     r2, sp                          @ regs
         bl      do_PrefetchAbort                @ call abort handler
 
@@ -329,6 +325,12 @@ __pabt_svc:
         @ restore SPSR and restart the instruction
         @
         ldr     r5, [sp, #S_PSR]
+#ifdef CONFIG_TRACE_IRQFLAGS
+        tst     r5, #PSR_I_BIT
+        bleq    trace_hardirqs_on
+        tst     r5, #PSR_I_BIT
+        blne    trace_hardirqs_off
+#endif
         svc_exit r5                             @ return from exception
  UNWIND(.fnend          )
 ENDPROC(__pabt_svc)
@@ -412,11 +414,6 @@ __dabt_usr:
         kuser_cmpxchg_check
         dabt_helper
 
-        @
-        @ IRQs on, then call the main handler
-        @
-        debug_entry r1
-        enable_irq
         mov     r2, sp
         adr     lr, BSYM(ret_from_exception)
         b       do_DataAbort
@@ -663,8 +660,6 @@ ENDPROC(__und_usr_unknown)
 __pabt_usr:
         usr_entry
         pabt_helper
-        debug_entry r1
-        enable_irq                              @ Enable interrupts
         mov     r2, sp                          @ regs
         bl      do_PrefetchAbort                @ call abort handler
  UNWIND(.fnend          )