diff options
| author | Jason Wessel <jason.wessel@windriver.com> | 2010-05-20 21:04:26 -0500 |
|---|---|---|
| committer | Jason Wessel <jason.wessel@windriver.com> | 2010-05-20 21:04:26 -0500 |
| commit | 5dd11d5d47d248850c58292513f0e164ba98b01e (patch) | |
| tree | fd3c5f27dd40d6a483483de3644ca060a5cafd75 /arch/mips/kernel/traps.c | |
| parent | ba797b28131b1f1367b662936ea370239d603cff (diff) | |
mips,kgdb: kdb low level trap catch and stack trace
The only way the debugger can handle a trap in inside rcu_lock,
notify_die, or atomic_notifier_call_chain without a recursive fault is
to have a low level "first opportunity handler" do_trap_or_bp() handler.
Generally this will be something the vast majority of folks will not
need, but for those who need it, it is added as a kernel .config
option called KGDB_LOW_LEVEL_TRAP.
Also added was a die notification for oops such that kdb can catch an
oops for analysis.
There appeared to be no obvious way to pass the struct pt_regs from
the original exception back to the stack back tracer, so a special
case was added to show_stack() for when kdb is active because you
generally desire to generally look at the back trace of the original
exception.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/kernel/traps.c')
| -rw-r--r-- | arch/mips/kernel/traps.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c index d612c6dcb746..950bde8813fc 100644 --- a/arch/mips/kernel/traps.c +++ b/arch/mips/kernel/traps.c @@ -26,6 +26,7 @@ #include <linux/kgdb.h> #include <linux/kdebug.h> #include <linux/notifier.h> +#include <linux/kdb.h> #include <asm/bootinfo.h> #include <asm/branch.h> @@ -185,6 +186,11 @@ void show_stack(struct task_struct *task, unsigned long *sp) regs.regs[29] = task->thread.reg29; regs.regs[31] = 0; regs.cp0_epc = task->thread.reg31; +#ifdef CONFIG_KGDB_KDB + } else if (atomic_read(&kgdb_active) != -1 && + kdb_current_regs) { + memcpy(®s, kdb_current_regs, sizeof(regs)); +#endif /* CONFIG_KGDB_KDB */ } else { prepare_frametrace(®s); } @@ -360,6 +366,8 @@ void __noreturn die(const char * str, struct pt_regs * regs) unsigned long dvpret = dvpe(); #endif /* CONFIG_MIPS_MT_SMTC */ + notify_die(DIE_OOPS, str, (struct pt_regs *)regs, SIGSEGV, 0, 0); + console_verbose(); spin_lock_irq(&die_lock); bust_spinlocks(1); @@ -704,6 +712,11 @@ static void do_trap_or_bp(struct pt_regs *regs, unsigned int code, siginfo_t info; char b[40]; +#ifdef CONFIG_KGDB_LOW_LEVEL_TRAP + if (kgdb_ll_trap(DIE_TRAP, str, regs, code, 0, 0) == NOTIFY_STOP) + return; +#endif /* CONFIG_KGDB_LOW_LEVEL_TRAP */ + if (notify_die(DIE_TRAP, str, regs, code, 0, 0) == NOTIFY_STOP) return; |