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Commit d300627c authored by Benjamin Herrenschmidt's avatar Benjamin Herrenschmidt Committed by Michael Ellerman
Browse files

powerpc/6xx: Handle DABR match before calling do_page_fault 



On legacy 6xx 32-bit procesors, we checked for the DABR match bit
in DSISR from do_page_fault(), in the middle of a pile of ifdef's
because all other CPU types do it in assembly prior to calling
do_page_fault. Fix that.

Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
[mpe: Add #ifdef CONFIG_6xx]
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
parent c433ec04

arch/powerpc/kernel/entry_32.S

+15 −0
Original line number Diff line number Diff line
@@ -586,7 +586,11 @@ ppc_swapcontext: 
handle_page_fault:

	stw	r4,_DAR(r1)

	addi	r3,r1,STACK_FRAME_OVERHEAD

	andis.  r0,r5,DSISR_DABRMATCH@h

#ifdef CONFIG_6xx

	bne-    handle_dabr_fault

	bl	do_page_fault

#endif

	cmpwi	r3,0

	beq+	ret_from_except

	SAVE_NVGPRS(r1)
@@ -599,6 +603,17 @@ handle_page_fault: 
	bl	bad_page_fault

	b	ret_from_except_full



#ifdef CONFIG_6xx

	/* We have a data breakpoint exception - handle it */

handle_dabr_fault:

	SAVE_NVGPRS(r1)

	lwz	r0,_TRAP(r1)

	clrrwi	r0,r0,1

	stw	r0,_TRAP(r1)

	bl      do_break

	b	ret_from_except_full

#endif



/*

 * This routine switches between two different tasks.  The process

 * state of one is saved on its kernel stack.  Then the state

arch/powerpc/mm/fault.c

+0 −9
Original line number Diff line number Diff line
@@ -242,15 +242,6 @@ static int __do_page_fault(struct pt_regs *regs, unsigned long address, 
		goto bail;

	}



#if !(defined(CONFIG_4xx) || defined(CONFIG_BOOKE) || \

      defined(CONFIG_PPC_BOOK3S_64) || defined(CONFIG_PPC_8xx))

  	if (error_code & DSISR_DABRMATCH) {

		/* breakpoint match */

		do_break(regs, address, error_code);

		goto bail;

	}

#endif



	/* We restore the interrupt state now */

	if (!arch_irq_disabled_regs(regs))

		local_irq_enable();