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Diffstat (limited to 'arch/blackfin/kernel/traps.c')
-rw-r--r--arch/blackfin/kernel/traps.c128
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