aboutsummaryrefslogtreecommitdiffstats
path: root/arch/tile/kernel/traps.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/tile/kernel/traps.c')
-rw-r--r--arch/tile/kernel/traps.c89
1 files changed, 68 insertions, 21 deletions
diff --git a/arch/tile/kernel/traps.c b/arch/tile/kernel/traps.c
index 5b19a23c8908..6b603d556ca6 100644
--- a/arch/tile/kernel/traps.c
+++ b/arch/tile/kernel/traps.c
@@ -15,6 +15,7 @@
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/kprobes.h>
+#include <linux/kdebug.h>
#include <linux/module.h>
#include <linux/reboot.h>
#include <linux/uaccess.h>
@@ -29,7 +30,7 @@
void __init trap_init(void)
{
- /* Nothing needed here since we link code at .intrpt1 */
+ /* Nothing needed here since we link code at .intrpt */
}
int unaligned_fixup = 1;
@@ -100,13 +101,7 @@ static int retry_gpv(unsigned int gpv_reason)
#endif /* CHIP_HAS_TILE_DMA() */
-#ifdef __tilegx__
-#define bundle_bits tilegx_bundle_bits
-#else
-#define bundle_bits tile_bundle_bits
-#endif
-
-extern bundle_bits bpt_code;
+extern tile_bundle_bits bpt_code;
asm(".pushsection .rodata.bpt_code,\"a\";"
".align 8;"
@@ -114,7 +109,7 @@ asm(".pushsection .rodata.bpt_code,\"a\";"
".size bpt_code,.-bpt_code;"
".popsection");
-static int special_ill(bundle_bits bundle, int *sigp, int *codep)
+static int special_ill(tile_bundle_bits bundle, int *sigp, int *codep)
{
int sig, code, maxcode;
@@ -214,24 +209,73 @@ static const char *const int_name[] = {
#endif
};
+static int do_bpt(struct pt_regs *regs)
+{
+ unsigned long bundle, bcode, bpt;
+
+ bundle = *(unsigned long *)instruction_pointer(regs);
+
+ /*
+ * bpt shoule be { bpt; nop }, which is 0x286a44ae51485000ULL.
+ * we encode the unused least significant bits for other purpose.
+ */
+ bpt = bundle & ~((1ULL << 12) - 1);
+ if (bpt != TILE_BPT_BUNDLE)
+ return 0;
+
+ bcode = bundle & ((1ULL << 12) - 1);
+ /*
+ * notify the kprobe handlers, if instruction is likely to
+ * pertain to them.
+ */
+ switch (bcode) {
+ /* breakpoint_insn */
+ case 0:
+ notify_die(DIE_BREAK, "debug", regs, bundle,
+ INT_ILL, SIGTRAP);
+ break;
+ /* compiled_bpt */
+ case DIE_COMPILED_BPT:
+ notify_die(DIE_COMPILED_BPT, "debug", regs, bundle,
+ INT_ILL, SIGTRAP);
+ break;
+ /* breakpoint2_insn */
+ case DIE_SSTEPBP:
+ notify_die(DIE_SSTEPBP, "single_step", regs, bundle,
+ INT_ILL, SIGTRAP);
+ break;
+ default:
+ return 0;
+ }
+
+ return 1;
+}
+
void __kprobes do_trap(struct pt_regs *regs, int fault_num,
unsigned long reason)
{
siginfo_t info = { 0 };
int signo, code;
unsigned long address = 0;
- bundle_bits instr;
+ tile_bundle_bits instr;
+ int is_kernel = !user_mode(regs);
+
+ /* Handle breakpoints, etc. */
+ if (is_kernel && fault_num == INT_ILL && do_bpt(regs))
+ return;
- /* Re-enable interrupts. */
- local_irq_enable();
+ /* Re-enable interrupts, if they were previously enabled. */
+ if (!(regs->flags & PT_FLAGS_DISABLE_IRQ))
+ local_irq_enable();
/*
* If it hits in kernel mode and we can't fix it up, just exit the
* current process and hope for the best.
*/
- if (!user_mode(regs)) {
+ if (is_kernel) {
const char *name;
- if (fixup_exception(regs)) /* only UNALIGN_DATA in practice */
+ char buf[100];
+ if (fixup_exception(regs)) /* ILL_TRANS or UNALIGN_DATA */
return;
if (fault_num >= 0 &&
fault_num < sizeof(int_name)/sizeof(int_name[0]) &&
@@ -239,10 +283,16 @@ void __kprobes do_trap(struct pt_regs *regs, int fault_num,
name = int_name[fault_num];
else
name = "Unknown interrupt";
- pr_alert("Kernel took bad trap %d (%s) at PC %#lx\n",
- fault_num, name, regs->pc);
if (fault_num == INT_GPV)
- pr_alert("GPV_REASON is %#lx\n", reason);
+ snprintf(buf, sizeof(buf), "; GPV_REASON %#lx", reason);
+#ifdef __tilegx__
+ else if (fault_num == INT_ILL_TRANS)
+ snprintf(buf, sizeof(buf), "; address %#lx", reason);
+#endif
+ else
+ buf[0] = '\0';
+ pr_alert("Kernel took bad trap %d (%s) at PC %#lx%s\n",
+ fault_num, name, regs->pc, buf);
show_regs(regs);
do_exit(SIGKILL); /* FIXME: implement i386 die() */
return;
@@ -324,11 +374,8 @@ void __kprobes do_trap(struct pt_regs *regs, int fault_num,
fill_ra_stack();
signo = SIGSEGV;
+ address = reason;
code = SEGV_MAPERR;
- if (reason & SPR_ILL_TRANS_REASON__I_STREAM_VA_RMASK)
- address = regs->pc;
- else
- address = 0; /* FIXME: GX: single-step for address */
break;
}
#endif