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* MIPS: Whitespace cleanup.Ralf Baechle2013-02-01
| | | | | | | | Having received another series of whitespace patches I decided to do this once and for all rather than dealing with this kind of patches trickling in forever. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* mips,kgdb: fix recursive page fault with CONFIG_KPROBESJason Wessel2012-10-12
| | | | | | | | | | | | | | | | | | | | | | This fault was detected using the kgdb test suite on boot and it crashes recursively due to the fact that CONFIG_KPROBES on mips adds an extra die notifier in the page fault handler. The crash signature looks like this: kgdbts:RUN bad memory access test KGDB: re-enter exception: ALL breakpoints killed Call Trace: [<807b7548>] dump_stack+0x20/0x54 [<807b7548>] dump_stack+0x20/0x54 The fix for now is to have kgdb return immediately if the fault type is DIE_PAGE_FAULT and allow the kprobe code to decide what is supposed to happen. Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: David S. Miller <davem@davemloft.net> Cc: <stable@vger.kernel.org> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
* MIPS: Fix a typo.Andrea Gelmini2010-10-04
| | | | | | | | | | | | "Userpace" -> "Userspace" Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net> Cc: Andrea Gelmini <andrea.gelmini@gelma.net> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Martin Hicks <mort@sgi.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/1536/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* kgdb,mips: remove unused kgdb_cpu_doing_single_step operationsJason Wessel2010-08-05
| | | | | | | | | | The mips kgdb specific code does not support software or HW single stepping so it should not implement Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Dongdong Deng <dongdong.deng@windriver.com> Acked-by: Ralf Baechle <ralf@linux-mips.org> CC: linux-mips@linux-mips.org
* kgdb,mips: Individual register get/set for mipsJason Wessel2010-08-05
| | | | | | | | | Implement the ability to individually get and set registers for kdb and kgdb for mips. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Ralf Baechle <ralf@linux-mips.org> CC: linux-mips@linux-mips.org
* mips,kgdb: kdb low level trap catch and stack traceJason Wessel2010-05-20
| | | | | | | | | | | | | | | | | | | | | | 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>
* kgdb: core changes to support kdbJason Wessel2010-05-20
| | | | | | | | | | | | | | | | | | | | | | | | | | These are the minimum changes to the kgdb core in order to enable an API to connect a new front end (kdb) to the debug core. This patch introduces the dbg_kdb_mode variable controls where the user level I/O is routed. It will be routed to the gdbstub (kgdb) or to the kdb front end which is a simple shell available over the kgdboc connection. You can switch back and forth between kdb or the gdb stub mode of operation dynamically. From gdb stub mode you can blindly type "$3#33", or from the kdb mode you can enter "kgdb" to switch to the gdb stub. The logic in the debug core depends on kdb to look for the typical gdb connection sequences and return immediately with KGDB_PASS_EVENT if a gdb serial command sequence is detected. That should allow a reasonably seamless transition between kdb -> gdb without leaving the kernel exception state. The two gdb serial queries that kdb is responsible for detecting are the "?" and "qSupported" packets. CC: Ingo Molnar <mingo@elte.hu> Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Martin Hicks <mort@sgi.com>
* MIPS: Build fix - include <linux/smp.h> into all smp_processor_id() users.Ralf Baechle2009-06-24
| | | | | | | | | Some of the were relying into smp.h being dragged in by another header which of course is fragile. <asm/cpu-info.h> uses smp_processor_id() only in macros and including smp.h there leads to an include loop, so don't change cpu-info.h. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* kgdb, x86, arm, mips, powerpc: ignore user space single steppingJason Wessel2008-09-26
| | | | | | | | | | | | | | | | | | | | On the x86 arch, user space single step exceptions should be ignored if they occur in the kernel space, such as ptrace stepping through a system call. First check if it is kgdb that is executing a single step, then ensure it is not an accidental traversal into the user space, while in kgdb, any other time the TIF_SINGLESTEP is set, kgdb should ignore the exception. On x86, arm, mips and powerpc, the kgdb_contthread usage was inconsistent with the way single stepping is implemented in the kgdb core. The arch specific stub should always set the kgdb_cpu_doing_single_step correctly if it is single stepping. This allows kgdb to correctly process an instruction steps if ptrace happens to be requesting an instruction step over a system call. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
* [MIPS] kgdb: Do not call fixup_exceptionAtsushi Nemoto2008-08-26
| | | | | | | | | kgdb_mips_notify is called on IBE/DBE/FPE/BP/TRAP/RI exception. None of them need fixup. And doing fixup for a breakpoint exception will confuse gdb. Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* [MIPS] kgdb: s/(void *)0)/NULL/Ralf Baechle2008-08-26
| | | | Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* [MIPS] kgdb: smp_call_function's 3rd argument is a pointer.Ralf Baechle2008-08-26
| | | | Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* [MIPS] kgdb: add arch support for the kernel's kgdb coreJason Wessel2008-07-30
The new kgdb architecture specific handler registers and unregisters dynamically for exceptions depending on when you configure a kgdb I/O driver. Aside from initializing the exceptions earlier in the boot process, kgdb should have no impact on a device when it is compiled in so long as an I/O module is not configured for use. There have been quite a number of contributors during the existence of this patch (see arch/mips/kernel/kgdb.c). Most recently Jason re-wrote the mips kgdb logic to use the die notification handlers. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>