d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
c67d07416a
freebsd-dev/gnu/usr.bin/gdb/kgdb/trgt_i386.c

97 lines
2.9 KiB
C
Raw Normal View History

Add the beginnings of kernel debugging support. the kgdb(1) tool is basicly a shell on top of libgdb that knows about kernel threads, kernel modules and kvm(3). As the word "beginnings" implies, not all of the features have been implemented yet. The tool is useful and I'd like feedback on the taken route. The simplest way to debug a kernel core file is: kgdb -n 0 This opens /var/crash/vmcore.0 with the corresponding kernel in the object directory (kernel.debug is used if it exists). Typical things that need to be added are: o Auto loading of kernel modules, o Handling of trapframes so that backtraces can be taken across them, o Some fancy commands to extract useful information out of a core file, o Various (probably many) other things.
2004-07-25 05:29:15 +00:00
/*
* Copyright (c) 2004 Marcel Moolenaar
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <machine/pcb.h>
#include <err.h>
#include <kvm.h>
#include <string.h>
#include <defs.h>
#include <target.h>
#include <gdbthread.h>
#include <inferior.h>
#include <regcache.h>
Add a kluge to allow kgdb(1) to inject its own frame sniffer in the list of frame sniffers so that trapframes can be detected. The kluge is needed because this version of gdb only supports appending a sniffer to the list of sniffers and the moment kgdb gets a chance to add its own frame sniffer, the target's default frame sniffer is already in the list. Since the default frame sniffer claims any frame thrown at it, kgdb's frame sniffer never gets to smell (a process much akin to tasting, but with lesser chance of hurling :-) This commit adds dummy frame sniffers that never claim a frame and as such don't fix anything yet. However, we now have frame sniffers and they are being called, so it's just a matter of adding meat to the bones and we'll be able to properly unwind across trapframes. MFC after: 1 week
2005-09-10 18:25:53 +00:00
#include <frame-unwind.h>
#include "kgdb.h"
Add the beginnings of kernel debugging support. the kgdb(1) tool is basicly a shell on top of libgdb that knows about kernel threads, kernel modules and kvm(3). As the word "beginnings" implies, not all of the features have been implemented yet. The tool is useful and I'd like feedback on the taken route. The simplest way to debug a kernel core file is: kgdb -n 0 This opens /var/crash/vmcore.0 with the corresponding kernel in the object directory (kernel.debug is used if it exists). Typical things that need to be added are: o Auto loading of kernel modules, o Handling of trapframes so that backtraces can be taken across them, o Some fancy commands to extract useful information out of a core file, o Various (probably many) other things.
2004-07-25 05:29:15 +00:00
void
kgdb_trgt_fetch_registers(int regno __unused)
{
struct kthr *kt;
struct pcb pcb;
Attempt to make kgdb little more useful and easy to use. Properly initialize it to recognise what ABI to use on amd64 (and possibly others) platform. Display PID and process name as a part of the 'info threads' output, TIDs alone are too confusing. Introduce new commmands 'tid <tid>' and 'proc <pid>' to accompany gdb's default 'thread <thread num>' to make the task of switching between different contexts easier.
2005-02-20 22:55:07 +00:00
kt = kgdb_thr_lookup_tid(ptid_get_tid(inferior_ptid));
Add the beginnings of kernel debugging support. the kgdb(1) tool is basicly a shell on top of libgdb that knows about kernel threads, kernel modules and kvm(3). As the word "beginnings" implies, not all of the features have been implemented yet. The tool is useful and I'd like feedback on the taken route. The simplest way to debug a kernel core file is: kgdb -n 0 This opens /var/crash/vmcore.0 with the corresponding kernel in the object directory (kernel.debug is used if it exists). Typical things that need to be added are: o Auto loading of kernel modules, o Handling of trapframes so that backtraces can be taken across them, o Some fancy commands to extract useful information out of a core file, o Various (probably many) other things.
2004-07-25 05:29:15 +00:00
if (kt == NULL)
return;
if (kvm_read(kvm, kt->pcb, &pcb, sizeof(pcb)) != sizeof(pcb)) {
warnx("kvm_read: %s", kvm_geterr(kvm));
memset(&pcb, 0, sizeof(pcb));
}
supply_register(3, (char *)&pcb.pcb_ebx);
supply_register(4, (char *)&pcb.pcb_esp);
supply_register(5, (char *)&pcb.pcb_ebp);
supply_register(6, (char *)&pcb.pcb_esi);
supply_register(7, (char *)&pcb.pcb_edi);
supply_register(8, (char *)&pcb.pcb_eip);
}
void
kgdb_trgt_store_registers(int regno __unused)
{
fprintf_unfiltered(gdb_stderr, "XXX: %s\n", __func__);
}
Add a kluge to allow kgdb(1) to inject its own frame sniffer in the list of frame sniffers so that trapframes can be detected. The kluge is needed because this version of gdb only supports appending a sniffer to the list of sniffers and the moment kgdb gets a chance to add its own frame sniffer, the target's default frame sniffer is already in the list. Since the default frame sniffer claims any frame thrown at it, kgdb's frame sniffer never gets to smell (a process much akin to tasting, but with lesser chance of hurling :-) This commit adds dummy frame sniffers that never claim a frame and as such don't fix anything yet. However, we now have frame sniffers and they are being called, so it's just a matter of adding meat to the bones and we'll be able to properly unwind across trapframes. MFC after: 1 week
2005-09-10 18:25:53 +00:00
static void
kgdb_trgt_trapframe_this_id(struct frame_info *next_frame, void **this_cache,
struct frame_id *this_id)
{
}
static void
kgdb_trgt_trapframe_prev_register(struct frame_info *next_frame,
void **this_cache, int regnum, int *optimizedp, enum lval_type *lvalp,
CORE_ADDR *addrp, int *realnump, void *valuep)
{
}
static const struct frame_unwind kgdb_trgt_trapframe_unwind = {
UNKNOWN_FRAME,
&kgdb_trgt_trapframe_this_id,
&kgdb_trgt_trapframe_prev_register
};
const struct frame_unwind *
kgdb_trgt_trapframe_sniffer(struct frame_info *next_frame)
{
return (NULL);
}
Reference in New Issue Copy Permalink