From 4e2bf01b21054b9300d2e108f5b8b5e4b803b8b8 Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Tue, 15 Jul 2014 20:25:02 +1000 Subject: [PATCH] powerpc: Move bad_stack() below the fwnmi_data_area At the moment the allmodconfig build is failing because we run out of space between altivec_assist() at 0x5700 and the fwnmi_data_area at 0x7000. Fixing it permanently will take some more work, but a quick fix is to move bad_stack() below the fwnmi_data_area. That gives us just enough room with everything enabled. bad_stack() is called from the common exception handlers, but it's a non-conditional branch, so we have plenty of scope to move it further way. Signed-off-by: Michael Ellerman Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/exceptions-64s.S | 120 +++++++++++++-------------- 1 file changed, 60 insertions(+), 60 deletions(-) diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index b859b3665be6..647d6c75ed62 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -952,66 +952,6 @@ system_call_entry: ppc64_runlatch_on_trampoline: b __ppc64_runlatch_on -/* - * Here we have detected that the kernel stack pointer is bad. - * R9 contains the saved CR, r13 points to the paca, - * r10 contains the (bad) kernel stack pointer, - * r11 and r12 contain the saved SRR0 and SRR1. - * We switch to using an emergency stack, save the registers there, - * and call kernel_bad_stack(), which panics. - */ -bad_stack: - ld r1,PACAEMERGSP(r13) - subi r1,r1,64+INT_FRAME_SIZE - std r9,_CCR(r1) - std r10,GPR1(r1) - std r11,_NIP(r1) - std r12,_MSR(r1) - mfspr r11,SPRN_DAR - mfspr r12,SPRN_DSISR - std r11,_DAR(r1) - std r12,_DSISR(r1) - mflr r10 - mfctr r11 - mfxer r12 - std r10,_LINK(r1) - std r11,_CTR(r1) - std r12,_XER(r1) - SAVE_GPR(0,r1) - SAVE_GPR(2,r1) - ld r10,EX_R3(r3) - std r10,GPR3(r1) - SAVE_GPR(4,r1) - SAVE_4GPRS(5,r1) - ld r9,EX_R9(r3) - ld r10,EX_R10(r3) - SAVE_2GPRS(9,r1) - ld r9,EX_R11(r3) - ld r10,EX_R12(r3) - ld r11,EX_R13(r3) - std r9,GPR11(r1) - std r10,GPR12(r1) - std r11,GPR13(r1) -BEGIN_FTR_SECTION - ld r10,EX_CFAR(r3) - std r10,ORIG_GPR3(r1) -END_FTR_SECTION_IFSET(CPU_FTR_CFAR) - SAVE_8GPRS(14,r1) - SAVE_10GPRS(22,r1) - lhz r12,PACA_TRAP_SAVE(r13) - std r12,_TRAP(r1) - addi r11,r1,INT_FRAME_SIZE - std r11,0(r1) - li r12,0 - std r12,0(r11) - ld r2,PACATOC(r13) - ld r11,exception_marker@toc(r2) - std r12,RESULT(r1) - std r11,STACK_FRAME_OVERHEAD-16(r1) -1: addi r3,r1,STACK_FRAME_OVERHEAD - bl kernel_bad_stack - b 1b - /* * Here r13 points to the paca, r9 contains the saved CR, * SRR0 and SRR1 are saved in r11 and r12, @@ -1636,3 +1576,63 @@ handle_dabr_fault: li r5,SIGSEGV bl bad_page_fault b ret_from_except + +/* + * Here we have detected that the kernel stack pointer is bad. + * R9 contains the saved CR, r13 points to the paca, + * r10 contains the (bad) kernel stack pointer, + * r11 and r12 contain the saved SRR0 and SRR1. + * We switch to using an emergency stack, save the registers there, + * and call kernel_bad_stack(), which panics. + */ +bad_stack: + ld r1,PACAEMERGSP(r13) + subi r1,r1,64+INT_FRAME_SIZE + std r9,_CCR(r1) + std r10,GPR1(r1) + std r11,_NIP(r1) + std r12,_MSR(r1) + mfspr r11,SPRN_DAR + mfspr r12,SPRN_DSISR + std r11,_DAR(r1) + std r12,_DSISR(r1) + mflr r10 + mfctr r11 + mfxer r12 + std r10,_LINK(r1) + std r11,_CTR(r1) + std r12,_XER(r1) + SAVE_GPR(0,r1) + SAVE_GPR(2,r1) + ld r10,EX_R3(r3) + std r10,GPR3(r1) + SAVE_GPR(4,r1) + SAVE_4GPRS(5,r1) + ld r9,EX_R9(r3) + ld r10,EX_R10(r3) + SAVE_2GPRS(9,r1) + ld r9,EX_R11(r3) + ld r10,EX_R12(r3) + ld r11,EX_R13(r3) + std r9,GPR11(r1) + std r10,GPR12(r1) + std r11,GPR13(r1) +BEGIN_FTR_SECTION + ld r10,EX_CFAR(r3) + std r10,ORIG_GPR3(r1) +END_FTR_SECTION_IFSET(CPU_FTR_CFAR) + SAVE_8GPRS(14,r1) + SAVE_10GPRS(22,r1) + lhz r12,PACA_TRAP_SAVE(r13) + std r12,_TRAP(r1) + addi r11,r1,INT_FRAME_SIZE + std r11,0(r1) + li r12,0 + std r12,0(r11) + ld r2,PACATOC(r13) + ld r11,exception_marker@toc(r2) + std r12,RESULT(r1) + std r11,STACK_FRAME_OVERHEAD-16(r1) +1: addi r3,r1,STACK_FRAME_OVERHEAD + bl kernel_bad_stack + b 1b -- 2.20.1