From 1f9b8936f36f4a8e1d9923f5d03295d668cdf098 Mon Sep 17 00:00:00 2001 From: Julien Thierry Date: Fri, 4 Aug 2017 09:31:42 +0100 Subject: arm64: Decode information from ESR upon mem faults When receiving unhandled faults from the CPU, description is very sparse. Adding information about faults decoded from ESR. Added defines to esr.h corresponding ESR fields. Values are based on ARM Archtecture Reference Manual (DDI 0487B.a), section D7.2.28 ESR_ELx, Exception Syndrome Register (ELx) (pages D7-2275 to D7-2280). New output is of the form: [ 77.818059] Mem abort info: [ 77.820826] Exception class = DABT (current EL), IL = 32 bits [ 77.826706] SET = 0, FnV = 0 [ 77.829742] EA = 0, S1PTW = 0 [ 77.832849] Data abort info: [ 77.835713] ISV = 0, ISS = 0x00000070 [ 77.839522] CM = 0, WnR = 1 Signed-off-by: Julien Thierry Cc: Will Deacon Cc: Mark Rutland [catalin.marinas@arm.com: fix "%lu" in a pr_alert() call] Signed-off-by: Catalin Marinas --- arch/arm64/mm/fault.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) (limited to 'arch/arm64/mm') diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index 2509e4fe6992..52ee273afeec 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -82,6 +82,49 @@ static inline int notify_page_fault(struct pt_regs *regs, unsigned int esr) } #endif +static void data_abort_decode(unsigned int esr) +{ + pr_alert("Data abort info:\n"); + + if (esr & ESR_ELx_ISV) { + pr_alert(" Access size = %u byte(s)\n", + 1U << ((esr & ESR_ELx_SAS) >> ESR_ELx_SAS_SHIFT)); + pr_alert(" SSE = %lu, SRT = %lu\n", + (esr & ESR_ELx_SSE) >> ESR_ELx_SSE_SHIFT, + (esr & ESR_ELx_SRT_MASK) >> ESR_ELx_SRT_SHIFT); + pr_alert(" SF = %lu, AR = %lu\n", + (esr & ESR_ELx_SF) >> ESR_ELx_SF_SHIFT, + (esr & ESR_ELx_AR) >> ESR_ELx_AR_SHIFT); + } else { + pr_alert(" ISV = 0, ISS = 0x%08lu\n", esr & ESR_ELx_ISS_MASK); + } + + pr_alert(" CM = %lu, WnR = %lu\n", + (esr & ESR_ELx_CM) >> ESR_ELx_CM_SHIFT, + (esr & ESR_ELx_WNR) >> ESR_ELx_WNR_SHIFT); +} + +/* + * Decode mem abort information + */ +static void mem_abort_decode(unsigned int esr) +{ + pr_alert("Mem abort info:\n"); + + pr_alert(" Exception class = %s, IL = %u bits\n", + esr_get_class_string(esr), + (esr & ESR_ELx_IL) ? 32 : 16); + pr_alert(" SET = %lu, FnV = %lu\n", + (esr & ESR_ELx_SET_MASK) >> ESR_ELx_SET_SHIFT, + (esr & ESR_ELx_FnV) >> ESR_ELx_FnV_SHIFT); + pr_alert(" EA = %lu, S1PTW = %lu\n", + (esr & ESR_ELx_EA) >> ESR_ELx_EA_SHIFT, + (esr & ESR_ELx_S1PTW) >> ESR_ELx_S1PTW_SHIFT); + + if (esr_is_data_abort(esr)) + data_abort_decode(esr); +} + /* * Dump out the page tables associated with 'addr' in the currently active mm. */ @@ -248,6 +291,8 @@ static void __do_kernel_fault(unsigned long addr, unsigned int esr, pr_alert("Unable to handle kernel %s at virtual address %08lx\n", msg, addr); + mem_abort_decode(esr); + show_pte(addr); die("Oops", regs, esr); bust_spinlocks(0); @@ -702,6 +747,8 @@ asmlinkage void __exception do_mem_abort(unsigned long addr, unsigned int esr, pr_alert("Unhandled fault: %s (0x%08x) at 0x%016lx\n", inf->name, esr, addr); + mem_abort_decode(esr); + info.si_signo = inf->sig; info.si_errno = 0; info.si_code = inf->code; -- cgit v1.2.3-59-g8ed1b