From 9f2f79e3a3c19ae745d0439d6e0eed31df28de3c Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Thu, 1 Mar 2012 15:47:44 +1100 Subject: [PATCH] powerpc: Disable interrupts in 64-bit kernel FP and vector faults If we get a floating point, altivec or vsx unavaible interrupt in kernel, we trigger a kernel error. There is no point preserving the interrupt state, in fact, that can even make debugging harder as the processor state might change (we may even preempt) between taking the exception and landing in a debugger. So just make those 3 disable interrupts unconditionally. Signed-off-by: Benjamin Herrenschmidt --- v2: On BookE only disable when hitting the kernel unavailable path, otherwise it will fail to restore softe as fast_exception_return doesn't do it. --- arch/powerpc/kernel/exceptions-64e.S | 7 +++---- arch/powerpc/kernel/exceptions-64s.S | 6 +++--- arch/powerpc/kernel/traps.c | 3 +++ 3 files changed, 9 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S index 573613d747a..3de9993c5c6 100644 --- a/arch/powerpc/kernel/exceptions-64e.S +++ b/arch/powerpc/kernel/exceptions-64e.S @@ -354,9 +354,9 @@ interrupt_end_book3e: /* we can probably do a shorter exception entry for that one... */ EXCEPTION_COMMON(0x800, PACA_EXGEN, INTS_KEEP) bne 1f /* if from user, just load it up */ + INTS_DISABLE_ALL bl .save_nvgprs addi r3,r1,STACK_FRAME_OVERHEAD - INTS_RESTORE_HARD bl .kernel_fp_unavailable_exception BUG_OPCODE 1: ld r12,_MSR(r1) @@ -391,10 +391,9 @@ interrupt_end_book3e: /* Auxiliary Processor Unavailable Interrupt */ START_EXCEPTION(ap_unavailable); NORMAL_EXCEPTION_PROLOG(0xf20, PROLOG_ADDITION_NONE) - EXCEPTION_COMMON(0xf20, PACA_EXGEN, INTS_KEEP) - addi r3,r1,STACK_FRAME_OVERHEAD + EXCEPTION_COMMON(0xf20, PACA_EXGEN, INTS_DISABLE_ALL) bl .save_nvgprs - INTS_RESTORE_HARD + addi r3,r1,STACK_FRAME_OVERHEAD bl .unknown_exception b .ret_from_except diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index d8ff6d37fc4..0fb42ae2169 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -762,8 +762,8 @@ fp_unavailable_common: EXCEPTION_PROLOG_COMMON(0x800, PACA_EXGEN) bne 1f /* if from user, just load it up */ bl .save_nvgprs + DISABLE_INTS addi r3,r1,STACK_FRAME_OVERHEAD - ENABLE_INTS bl .kernel_fp_unavailable_exception BUG_OPCODE 1: bl .load_up_fpu @@ -782,8 +782,8 @@ BEGIN_FTR_SECTION END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC) #endif bl .save_nvgprs + DISABLE_INTS addi r3,r1,STACK_FRAME_OVERHEAD - ENABLE_INTS bl .altivec_unavailable_exception b .ret_from_except @@ -798,8 +798,8 @@ BEGIN_FTR_SECTION END_FTR_SECTION_IFSET(CPU_FTR_VSX) #endif bl .save_nvgprs + DISABLE_INTS addi r3,r1,STACK_FRAME_OVERHEAD - ENABLE_INTS bl .vsx_unavailable_exception b .ret_from_except diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 5d40e592ffc..a750409ccc4 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -247,6 +247,9 @@ void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr) addr, regs->nip, regs->link, code); } + if (!arch_irq_disabled_regs(regs)) + local_irq_enable(); + memset(&info, 0, sizeof(info)); info.si_signo = signr; info.si_code = code; -- 2.39.5