diff options
Diffstat (limited to 'arch/blackfin/kernel/traps.c')
| -rw-r--r-- | arch/blackfin/kernel/traps.c | 128 |
1 files changed, 78 insertions, 50 deletions
diff --git a/arch/blackfin/kernel/traps.c b/arch/blackfin/kernel/traps.c index aa76dfb0226..d279552fe9b 100644 --- a/arch/blackfin/kernel/traps.c +++ b/arch/blackfin/kernel/traps.c @@ -27,6 +27,7 @@ * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ +#include <linux/bug.h> #include <linux/uaccess.h> #include <linux/interrupt.h> #include <linux/module.h> @@ -238,6 +239,11 @@ asmlinkage void double_fault_c(struct pt_regs *fp) } +static int kernel_mode_regs(struct pt_regs *regs) +{ + return regs->ipend & 0xffc0; +} + asmlinkage void trap_c(struct pt_regs *fp) { #ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON @@ -246,6 +252,7 @@ asmlinkage void trap_c(struct pt_regs *fp) #ifdef CONFIG_DEBUG_HUNT_FOR_ZERO unsigned int cpu = smp_processor_id(); #endif + const char *strerror = NULL; int sig = 0; siginfo_t info; unsigned long trapnr = fp->seqstat & SEQSTAT_EXCAUSE; @@ -259,27 +266,10 @@ asmlinkage void trap_c(struct pt_regs *fp) * double faults if the stack has become corrupt */ - /* If the fault was caused by a kernel thread, or interrupt handler - * we will kernel panic, so the system reboots. - * If KGDB is enabled, don't set this for kernel breakpoints - */ - - /* TODO: check to see if we are in some sort of deferred HWERR - * that we should be able to recover from, not kernel panic - */ - if ((bfin_read_IPEND() & 0xFFC0) && (trapnr != VEC_STEP) -#ifdef CONFIG_KGDB - && (trapnr != VEC_EXCPT02) +#ifndef CONFIG_KGDB + /* IPEND is skipped if KGDB isn't enabled (see entry code) */ + fp->ipend = bfin_read_IPEND(); #endif - ){ - console_verbose(); - oops_in_progress = 1; - } else if (current) { - if (current->mm == NULL) { - console_verbose(); - oops_in_progress = 1; - } - } /* trap_c() will be called for exceptions. During exceptions * processing, the pc value should be set with retx value. @@ -307,15 +297,15 @@ asmlinkage void trap_c(struct pt_regs *fp) sig = SIGTRAP; CHK_DEBUGGER_TRAP_MAYBE(); /* Check if this is a breakpoint in kernel space */ - if (fp->ipend & 0xffc0) - return; + if (kernel_mode_regs(fp)) + goto traps_done; else break; /* 0x03 - User Defined, userspace stack overflow */ case VEC_EXCPT03: info.si_code = SEGV_STACKFLOW; sig = SIGSEGV; - verbose_printk(KERN_NOTICE EXC_0x03(KERN_NOTICE)); + strerror = KERN_NOTICE EXC_0x03(KERN_NOTICE); CHK_DEBUGGER_TRAP_MAYBE(); break; /* 0x02 - KGDB initial connection and break signal trap */ @@ -324,7 +314,7 @@ asmlinkage void trap_c(struct pt_regs *fp) info.si_code = TRAP_ILLTRAP; sig = SIGTRAP; CHK_DEBUGGER_TRAP(); - return; + goto traps_done; #endif /* 0x04 - User Defined */ /* 0x05 - User Defined */ @@ -344,7 +334,7 @@ asmlinkage void trap_c(struct pt_regs *fp) case VEC_EXCPT04 ... VEC_EXCPT15: info.si_code = ILL_ILLPARAOP; sig = SIGILL; - verbose_printk(KERN_NOTICE EXC_0x04(KERN_NOTICE)); + strerror = KERN_NOTICE EXC_0x04(KERN_NOTICE); CHK_DEBUGGER_TRAP_MAYBE(); break; /* 0x10 HW Single step, handled here */ @@ -353,15 +343,15 @@ asmlinkage void trap_c(struct pt_regs *fp) sig = SIGTRAP; CHK_DEBUGGER_TRAP_MAYBE(); /* Check if this is a single step in kernel space */ - if (fp->ipend & 0xffc0) - return; + if (kernel_mode_regs(fp)) + goto traps_done; else break; /* 0x11 - Trace Buffer Full, handled here */ case VEC_OVFLOW: info.si_code = TRAP_TRACEFLOW; sig = SIGTRAP; - verbose_printk(KERN_NOTICE EXC_0x11(KERN_NOTICE)); + strerror = KERN_NOTICE EXC_0x11(KERN_NOTICE); CHK_DEBUGGER_TRAP_MAYBE(); break; /* 0x12 - Reserved, Caught by default */ @@ -381,37 +371,54 @@ asmlinkage void trap_c(struct pt_regs *fp) /* 0x20 - Reserved, Caught by default */ /* 0x21 - Undefined Instruction, handled here */ case VEC_UNDEF_I: +#ifdef CONFIG_BUG + if (kernel_mode_regs(fp)) { + switch (report_bug(fp->pc, fp)) { + case BUG_TRAP_TYPE_NONE: + break; + case BUG_TRAP_TYPE_WARN: + dump_bfin_trace_buffer(); + fp->pc += 2; + goto traps_done; + case BUG_TRAP_TYPE_BUG: + /* call to panic() will dump trace, and it is + * off at this point, so it won't be clobbered + */ + panic("BUG()"); + } + } +#endif info.si_code = ILL_ILLOPC; sig = SIGILL; - verbose_printk(KERN_NOTICE EXC_0x21(KERN_NOTICE)); + strerror = KERN_NOTICE EXC_0x21(KERN_NOTICE); CHK_DEBUGGER_TRAP_MAYBE(); break; /* 0x22 - Illegal Instruction Combination, handled here */ case VEC_ILGAL_I: info.si_code = ILL_ILLPARAOP; sig = SIGILL; - verbose_printk(KERN_NOTICE EXC_0x22(KERN_NOTICE)); + strerror = KERN_NOTICE EXC_0x22(KERN_NOTICE); CHK_DEBUGGER_TRAP_MAYBE(); break; /* 0x23 - Data CPLB protection violation, handled here */ case VEC_CPLB_VL: info.si_code = ILL_CPLB_VI; sig = SIGBUS; - verbose_printk(KERN_NOTICE EXC_0x23(KERN_NOTICE)); + strerror = KERN_NOTICE EXC_0x23(KERN_NOTICE); CHK_DEBUGGER_TRAP_MAYBE(); break; /* 0x24 - Data access misaligned, handled here */ case VEC_MISALI_D: info.si_code = BUS_ADRALN; sig = SIGBUS; - verbose_printk(KERN_NOTICE EXC_0x24(KERN_NOTICE)); + strerror = KERN_NOTICE EXC_0x24(KERN_NOTICE); CHK_DEBUGGER_TRAP_MAYBE(); break; /* 0x25 - Unrecoverable Event, handled here */ case VEC_UNCOV: info.si_code = ILL_ILLEXCPT; sig = SIGILL; - verbose_printk(KERN_NOTICE EXC_0x25(KERN_NOTICE)); + strerror = KERN_NOTICE EXC_0x25(KERN_NOTICE); CHK_DEBUGGER_TRAP_MAYBE(); break; /* 0x26 - Data CPLB Miss, normal case is handled in _cplb_hdr, @@ -419,7 +426,7 @@ asmlinkage void trap_c(struct pt_regs *fp) case VEC_CPLB_M: info.si_code = BUS_ADRALN; sig = SIGBUS; - verbose_printk(KERN_NOTICE EXC_0x26(KERN_NOTICE)); + strerror = KERN_NOTICE EXC_0x26(KERN_NOTICE); break; /* 0x27 - Data CPLB Multiple Hits - Linux Trap Zero, handled here */ case VEC_CPLB_MHIT: @@ -427,10 +434,10 @@ asmlinkage void trap_c(struct pt_regs *fp) sig = SIGSEGV; #ifdef CONFIG_DEBUG_HUNT_FOR_ZERO if (cpu_pda[cpu].dcplb_fault_addr < FIXED_CODE_START) - verbose_printk(KERN_NOTICE "NULL pointer access\n"); + strerror = KERN_NOTICE "NULL pointer access\n"; else #endif - verbose_printk(KERN_NOTICE EXC_0x27(KERN_NOTICE)); + strerror = KERN_NOTICE EXC_0x27(KERN_NOTICE); CHK_DEBUGGER_TRAP_MAYBE(); break; /* 0x28 - Emulation Watchpoint, handled here */ @@ -440,8 +447,8 @@ asmlinkage void trap_c(struct pt_regs *fp) pr_debug(EXC_0x28(KERN_DEBUG)); CHK_DEBUGGER_TRAP_MAYBE(); /* Check if this is a watchpoint in kernel space */ - if (fp->ipend & 0xffc0) - return; + if (kernel_mode_regs(fp)) + goto traps_done; else break; #ifdef CONFIG_BF535 @@ -449,7 +456,7 @@ asmlinkage void trap_c(struct pt_regs *fp) case VEC_ISTRU_VL: /* ADSP-BF535 only (MH) */ info.si_code = BUS_OPFETCH; sig = SIGBUS; - verbose_printk(KERN_NOTICE "BF535: VEC_ISTRU_VL\n"); + strerror = KERN_NOTICE "BF535: VEC_ISTRU_VL\n"; CHK_DEBUGGER_TRAP_MAYBE(); break; #else @@ -459,21 +466,21 @@ asmlinkage void trap_c(struct pt_regs *fp) case VEC_MISALI_I: info.si_code = BUS_ADRALN; sig = SIGBUS; - verbose_printk(KERN_NOTICE EXC_0x2A(KERN_NOTICE)); + strerror = KERN_NOTICE EXC_0x2A(KERN_NOTICE); CHK_DEBUGGER_TRAP_MAYBE(); break; /* 0x2B - Instruction CPLB protection violation, handled here */ case VEC_CPLB_I_VL: info.si_code = ILL_CPLB_VI; sig = SIGBUS; - verbose_printk(KERN_NOTICE EXC_0x2B(KERN_NOTICE)); + strerror = KERN_NOTICE EXC_0x2B(KERN_NOTICE); CHK_DEBUGGER_TRAP_MAYBE(); break; /* 0x2C - Instruction CPLB miss, handled in _cplb_hdr */ case VEC_CPLB_I_M: info.si_code = ILL_CPLB_MISS; sig = SIGBUS; - verbose_printk(KERN_NOTICE EXC_0x2C(KERN_NOTICE)); + strerror = KERN_NOTICE EXC_0x2C(KERN_NOTICE); break; /* 0x2D - Instruction CPLB Multiple Hits, handled here */ case VEC_CPLB_I_MHIT: @@ -481,17 +488,17 @@ asmlinkage void trap_c(struct pt_regs *fp) sig = SIGSEGV; #ifdef CONFIG_DEBUG_HUNT_FOR_ZERO if (cpu_pda[cpu].icplb_fault_addr < FIXED_CODE_START) - verbose_printk(KERN_NOTICE "Jump to NULL address\n"); + strerror = KERN_NOTICE "Jump to NULL address\n"; else #endif - verbose_printk(KERN_NOTICE EXC_0x2D(KERN_NOTICE)); + strerror = KERN_NOTICE EXC_0x2D(KERN_NOTICE); CHK_DEBUGGER_TRAP_MAYBE(); break; /* 0x2E - Illegal use of Supervisor Resource, handled here */ case VEC_ILL_RES: info.si_code = ILL_PRVOPC; sig = SIGILL; - verbose_printk(KERN_NOTICE EXC_0x2E(KERN_NOTICE)); + strerror = KERN_NOTICE EXC_0x2E(KERN_NOTICE); CHK_DEBUGGER_TRAP_MAYBE(); break; /* 0x2F - Reserved, Caught by default */ @@ -519,17 +526,17 @@ asmlinkage void trap_c(struct pt_regs *fp) case (SEQSTAT_HWERRCAUSE_SYSTEM_MMR): info.si_code = BUS_ADRALN; sig = SIGBUS; - verbose_printk(KERN_NOTICE HWC_x2(KERN_NOTICE)); + strerror = KERN_NOTICE HWC_x2(KERN_NOTICE); break; /* External Memory Addressing Error */ case (SEQSTAT_HWERRCAUSE_EXTERN_ADDR): info.si_code = BUS_ADRERR; sig = SIGBUS; - verbose_printk(KERN_NOTICE HWC_x3(KERN_NOTICE)); + strerror = KERN_NOTICE HWC_x3(KERN_NOTICE); break; /* Performance Monitor Overflow */ case (SEQSTAT_HWERRCAUSE_PERF_FLOW): - verbose_printk(KERN_NOTICE HWC_x12(KERN_NOTICE)); + strerror = KERN_NOTICE HWC_x12(KERN_NOTICE); break; /* RAISE 5 instruction */ case (SEQSTAT_HWERRCAUSE_RAISE_5): @@ -546,7 +553,6 @@ asmlinkage void trap_c(struct pt_regs *fp) * if we get here we hit a reserved one, so panic */ default: - oops_in_progress = 1; info.si_code = ILL_ILLPARAOP; sig = SIGILL; verbose_printk(KERN_EMERG "Caught Unhandled Exception, code = %08lx\n", @@ -557,6 +563,16 @@ asmlinkage void trap_c(struct pt_regs *fp) BUG_ON(sig == 0); + /* If the fault was caused by a kernel thread, or interrupt handler + * we will kernel panic, so the system reboots. + */ + if (kernel_mode_regs(fp) || (current && !current->mm)) { + console_verbose(); + oops_in_progress = 1; + if (strerror) + verbose_printk(strerror); + } + if (sig != SIGTRAP) { dump_bfin_process(fp); dump_bfin_mem(fp); @@ -606,8 +622,8 @@ asmlinkage void trap_c(struct pt_regs *fp) if (ANOMALY_05000461 && trapnr == VEC_HWERR && !access_ok(VERIFY_READ, fp->pc, 8)) fp->pc = SAFE_USER_INSTRUCTION; + traps_done: trace_buffer_restore(j); - return; } /* Typical exception handling routines */ @@ -792,6 +808,18 @@ void dump_bfin_trace_buffer(void) } EXPORT_SYMBOL(dump_bfin_trace_buffer); +#ifdef CONFIG_BUG +int is_valid_bugaddr(unsigned long addr) +{ + unsigned short opcode; + + if (!get_instruction(&opcode, (unsigned short *)addr)) + return 0; + + return opcode == BFIN_BUG_OPCODE; +} +#endif + /* * Checks to see if the address pointed to is either a * 16-bit CALL instruction, or a 32-bit CALL instruction |