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Diffstat (limited to 'arch/tile/kernel/traps.c')
-rw-r--r--arch/tile/kernel/traps.c136
1 files changed, 109 insertions, 27 deletions
diff --git a/arch/tile/kernel/traps.c b/arch/tile/kernel/traps.c
index 4f47b8a356d..f3ceb6308e4 100644
--- a/arch/tile/kernel/traps.c
+++ b/arch/tile/kernel/traps.c
@@ -15,12 +15,14 @@
#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>
#include <linux/ptrace.h>
#include <asm/stack.h>
#include <asm/traps.h>
+#include <asm/setup.h>
#include <arch/interrupts.h>
#include <arch/spr_def.h>
@@ -28,7 +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;
@@ -40,10 +42,9 @@ static int __init setup_unaligned_fixup(char *str)
* will still parse the instruction, then fire a SIGBUS with
* the correct address from inside the single_step code.
*/
- long val;
- if (strict_strtol(str, 0, &val) != 0)
+ if (kstrtoint(str, 0, &unaligned_fixup) != 0)
return 0;
- unaligned_fixup = val;
+
pr_info("Fixups for unaligned data accesses are %s\n",
unaligned_fixup >= 0 ?
(unaligned_fixup ? "enabled" : "disabled") :
@@ -99,13 +100,7 @@ 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;"
@@ -113,7 +108,7 @@ 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;
@@ -194,34 +189,119 @@ static int special_ill(bundle_bits bundle, int *sigp, int *codep)
return 1;
}
+static const char *const int_name[] = {
+ [INT_MEM_ERROR] = "Memory error",
+ [INT_ILL] = "Illegal instruction",
+ [INT_GPV] = "General protection violation",
+ [INT_UDN_ACCESS] = "UDN access",
+ [INT_IDN_ACCESS] = "IDN access",
+#if CHIP_HAS_SN()
+ [INT_SN_ACCESS] = "SN access",
+#endif
+ [INT_SWINT_3] = "Software interrupt 3",
+ [INT_SWINT_2] = "Software interrupt 2",
+ [INT_SWINT_0] = "Software interrupt 0",
+ [INT_UNALIGN_DATA] = "Unaligned data",
+ [INT_DOUBLE_FAULT] = "Double fault",
+#ifdef __tilegx__
+ [INT_ILL_TRANS] = "Illegal virtual address",
+#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;
- bundle_bits instr;
+ unsigned long address = 0;
+ 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 (fixup_exception(regs)) /* only UNALIGN_DATA in practice */
+ if (is_kernel) {
+ const char *name;
+ char buf[100];
+ if (fixup_exception(regs)) /* ILL_TRANS or UNALIGN_DATA */
return;
- pr_alert("Kernel took bad trap %d at PC %#lx\n",
- fault_num, regs->pc);
+ if (fault_num >= 0 &&
+ fault_num < sizeof(int_name)/sizeof(int_name[0]) &&
+ int_name[fault_num] != NULL)
+ name = int_name[fault_num];
+ else
+ name = "Unknown interrupt";
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;
}
switch (fault_num) {
+ case INT_MEM_ERROR:
+ signo = SIGBUS;
+ code = BUS_OBJERR;
+ break;
case INT_ILL:
if (copy_from_user(&instr, (void __user *)regs->pc,
sizeof(instr))) {
@@ -288,14 +368,15 @@ void __kprobes do_trap(struct pt_regs *regs, int fault_num,
address = regs->pc;
break;
#ifdef __tilegx__
- case INT_ILL_TRANS:
+ case INT_ILL_TRANS: {
+ /* Avoid a hardware erratum with the return address stack. */
+ 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
default:
panic("Unexpected do_trap interrupt number %d", fault_num);
@@ -307,7 +388,8 @@ void __kprobes do_trap(struct pt_regs *regs, int fault_num,
info.si_addr = (void __user *)address;
if (signo == SIGILL)
info.si_trapno = fault_num;
- trace_unhandled_signal("trap", regs, address, signo);
+ if (signo != SIGTRAP)
+ trace_unhandled_signal("trap", regs, address, signo);
force_sig_info(signo, &info, current);
}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-09 22:56:12 +0000