From 2e0c35398db447a1fbe111c52507afe4eb313971 Mon Sep 17 00:00:00 2001 From: Mark Kettenis Date: Sat, 22 May 2004 17:21:36 +0000 Subject: [PATCH] * bsd-kvm.c, bsd-kvm.h: New files. * i386fbsd-nat.c: Include , and "bsd-kvm.h". (i386fbsd_supply_pcb): New function. * Makefile.in (ALLDEPFILES): Add bsd-kvm.c. (i386fbsd-nat.o): Update dependencies. (bsd_kvm_h): New variable. (bsd-kvm.o): New dependency. * config/i386/fbsd.mh (NATDEPFILES): Add bsd-kvm.o. (LOADLIBES): New variable. --- gdb/ChangeLog | 11 +++ gdb/Makefile.in | 6 +- gdb/bsd-kvm.c | 226 ++++++++++++++++++++++++++++++++++++++++++++++++ gdb/bsd-kvm.h | 35 ++++++++ gdb/config/i386/fbsd.mh | 5 +- gdb/i386fbsd-nat.c | 46 +++++++++- 6 files changed, 324 insertions(+), 5 deletions(-) create mode 100644 gdb/bsd-kvm.c create mode 100644 gdb/bsd-kvm.h diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 9875c8b..f95f533 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,5 +1,16 @@ 2004-05-22 Mark Kettenis + * bsd-kvm.c, bsd-kvm.h: New files. + * i386fbsd-nat.c: Include , and + "bsd-kvm.h". + (i386fbsd_supply_pcb): New function. + * Makefile.in (ALLDEPFILES): Add bsd-kvm.c. + (i386fbsd-nat.o): Update dependencies. + (bsd_kvm_h): New variable. + (bsd-kvm.o): New dependency. + * config/i386/fbsd.mh (NATDEPFILES): Add bsd-kvm.o. + (LOADLIBES): New variable. + * regset.c: Tweak comment. (regset_alloc): Remove descr argument. Use GDBARCH_OBSTACK_ZALLOC macro. diff --git a/gdb/Makefile.in b/gdb/Makefile.in index effe5c1..f10df4e 100644 --- a/gdb/Makefile.in +++ b/gdb/Makefile.in @@ -631,6 +631,7 @@ bcache_h = bcache.h bfd_target_h = bfd-target.h block_h = block.h breakpoint_h = breakpoint.h $(frame_h) $(value_h) $(gdb_events_h) +bsd_kvm_h = bsd-kvm.h buildsym_h = buildsym.h call_cmds_h = call-cmds.h charset_h = charset.h @@ -1322,6 +1323,7 @@ ALLDEPFILES = \ arm-linux-nat.c arm-linux-tdep.c arm-tdep.c \ armnbsd-nat.c armnbsd-tdep.c \ avr-tdep.c \ + bsd-kvm.c \ coff-solib.c \ core-regset.c core-aout.c corelow.c \ dcache.c dpx2-nat.c exec.c fork-child.c \ @@ -1613,6 +1615,8 @@ breakpoint.o: breakpoint.c $(defs_h) $(symtab_h) $(frame_h) $(breakpoint_h) \ $(objfiles_h) $(source_h) $(linespec_h) $(completer_h) $(gdb_h) \ $(ui_out_h) $(cli_script_h) $(gdb_assert_h) $(block_h) \ $(gdb_events_h) +bsd-kvm.o: bsd-kvm.c $(defs_h) $(frame_h) $(regcache_h) $(target_h) \ + $(gdb_assert_h) $(readline_h) $(bsd_kvm_h) buildsym.o: buildsym.c $(defs_h) $(bfd_h) $(gdb_obstack_h) $(symtab_h) \ $(symfile_h) $(objfiles_h) $(gdbtypes_h) $(gdb_assert_h) \ $(complaints_h) $(gdb_string_h) $(expression_h) $(language_h) \ @@ -1854,7 +1858,7 @@ i386bsd-tdep.o: i386bsd-tdep.c $(defs_h) $(arch_utils_h) $(frame_h) \ i386-cygwin-tdep.o: i386-cygwin-tdep.c $(defs_h) $(osabi_h) $(gdb_string_h) \ $(i386_tdep_h) i386fbsd-nat.o: i386fbsd-nat.c $(defs_h) $(inferior_h) $(regcache_h) \ - $(i386_tdep_h) + $(i386_tdep_h) $(bsd_kvm_h) i386fbsd-tdep.o: i386fbsd-tdep.c $(defs_h) $(arch_utils_h) $(osabi_h) \ $(i386_tdep_h) $(i387_tdep_h) $(solib_svr4_h) i386gnu-nat.o: i386gnu-nat.c $(defs_h) $(inferior_h) $(floatformat_h) \ diff --git a/gdb/bsd-kvm.c b/gdb/bsd-kvm.c new file mode 100644 index 0000000..37fc2b4 --- /dev/null +++ b/gdb/bsd-kvm.c @@ -0,0 +1,226 @@ +/* BSD Kernel Data Access Library (libkvm) interface. + + Copyright 2004 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#include "defs.h" +#include "frame.h" +#include "regcache.h" +#include "target.h" + +#include "gdb_assert.h" +#include +#include +#include +#include "readline/readline.h" +#include +#include + +#include "bsd-kvm.h" + +/* Kernel memory interface descriptor. */ +kvm_t *core_kd; + +/* Address of process control block. */ +struct pcb *bsd_kvm_paddr; + +/* Pointer to architecture-specific function that reconstructs the + register state from PCB and supplies it to REGCACHE. */ +int (*bsd_kvm_supply_pcb)(struct regcache *regcache, struct pcb *pcb); + +/* Target ops for libkvm interface. */ +struct target_ops bsd_kvm_ops; + +static void +bsd_kvm_open (char *filename, int from_tty) +{ + char errbuf[_POSIX2_LINE_MAX]; + char *execfile = NULL; + kvm_t *temp_kd; + + target_preopen (from_tty); + + if (filename) + { + char *temp; + + filename = tilde_expand (filename); + if (filename[0] != '/') + { + temp = concat (current_directory, "/", filename, NULL); + xfree (filename); + filename = temp; + } + } + + temp_kd = kvm_openfiles (execfile, filename, NULL, O_RDONLY, errbuf); + if (temp_kd == NULL) + error ("%s", errbuf); + + unpush_target (&bsd_kvm_ops); + core_kd = temp_kd; + push_target (&bsd_kvm_ops); + + target_fetch_registers (-1); + + flush_cached_frames (); + select_frame (get_current_frame ()); + print_stack_frame (get_selected_frame (), -1, 1); +} + +static void +bsd_kvm_close (int quitting) +{ + if (core_kd) + { + if (kvm_close (core_kd) == -1) + warning ("%s", kvm_geterr(core_kd)); + core_kd = NULL; + } +} + +static int +bsd_kvm_xfer_memory (CORE_ADDR memaddr, char *myaddr, int len, + int write, struct mem_attrib *attrib, + struct target_ops *ops) +{ + if (write) + return kvm_write (core_kd, memaddr, myaddr, len); + else + return kvm_read (core_kd, memaddr, myaddr, len); + + return -1; +} + +/* Fetch process control block at address PADDR. */ + +static int +bsd_kvm_fetch_pcb (struct pcb *paddr) +{ + struct pcb pcb; + + if (kvm_read (core_kd, (unsigned long) paddr, &pcb, sizeof pcb) == -1) + error ("%s", kvm_geterr (core_kd)); + + gdb_assert (bsd_kvm_supply_pcb); + return bsd_kvm_supply_pcb (current_regcache, &pcb); +} + +static void +bsd_kvm_fetch_registers (int regnum) +{ + struct nlist nl[2]; + + if (bsd_kvm_paddr) + bsd_kvm_fetch_pcb (bsd_kvm_paddr); + + /* On dumping core, BSD kernels store the faulting context (PCB) + in the variable "dumppcb". */ + memset (nl, 0, sizeof nl); + nl[0].n_name = "_dumppcb"; + + if (kvm_nlist (core_kd, nl) == -1) + error ("%s", kvm_geterr (core_kd)); + + if (nl[0].n_value != 0) + { + /* Found dumppcb. If it contains a valid context, return + immediately. */ + if (bsd_kvm_fetch_pcb ((struct pcb *) nl[0].n_value)) + return; + } + + /* Traditional BSD kernels have a process proc0 that should always + be present. The address of proc0's PCB is stored in the variable + "proc0paddr". */ + + memset (nl, 0, sizeof nl); + nl[0].n_name = "_proc0paddr"; + + if (kvm_nlist (core_kd, nl) == -1) + error ("%s", kvm_geterr (core_kd)); + + if (nl[0].n_value != 0) + { + struct pcb *paddr; + + /* Found proc0paddr. */ + if (kvm_read (core_kd, nl[0].n_value, &paddr, sizeof paddr) == -1) + error ("%s", kvm_geterr (core_kd)); + + bsd_kvm_fetch_pcb (paddr); + return; + } + +#ifdef HAVE_STRUCT_THREAD_TD_PCB + /* In FreeBSD kernels for 5.0-RELEASE and later, the PCB no longer + lives in `struct proc' but in `struct thread'. The `struct + thread' for the initial thread for proc0 can be found in the + variable "thread0". */ + + memset (nl, 0, sizeof nl); + nl[0].n_name = "_thread0"; + + if (kvm_nlist (core_kd, nl) == -1) + error ("%s", kvm_geterr (core_kd)); + + if (nl[0].n_value != 0) + { + struct pcb *paddr; + + /* Found thread0. */ + nl[1].n_value += offsetof (struct thread, td_pcb); + if (kvm_read (core_kd, nl[1].n_value, &paddr, sizeof paddr) == -1) + error ("%s", kvm_geterr (core_kd)); + + bsd_kvm_fetch_pcb (paddr); + return; + } +#endif + + error ("Cannot find a valid PCB"); +} + + +/* Add the libkvm interface to the list of all possible targets and + register CUPPLY_PCB as the architecture-specific process control + block interpreter. */ + +void +bsd_kvm_add_target (int (*supply_pcb)(struct regcache *, struct pcb *)) +{ + gdb_assert (bsd_kvm_supply_pcb == NULL); + bsd_kvm_supply_pcb = supply_pcb; + + bsd_kvm_ops.to_shortname = "kvm"; + bsd_kvm_ops.to_longname = "Kernel memory interface"; + bsd_kvm_ops.to_doc = "Use a kernel virtual memory image as a target.\n\ +Optionally specify the filename of a core dump."; + bsd_kvm_ops.to_open = bsd_kvm_open; + bsd_kvm_ops.to_close = bsd_kvm_close; + bsd_kvm_ops.to_fetch_registers = bsd_kvm_fetch_registers; + bsd_kvm_ops.to_xfer_memory = bsd_kvm_xfer_memory; + bsd_kvm_ops.to_stratum = process_stratum; + bsd_kvm_ops.to_has_memory = 1; + bsd_kvm_ops.to_has_stack = 1; + bsd_kvm_ops.to_has_registers = 1; + bsd_kvm_ops.to_magic = OPS_MAGIC; + + add_target (&bsd_kvm_ops); +} diff --git a/gdb/bsd-kvm.h b/gdb/bsd-kvm.h new file mode 100644 index 0000000..0660776 --- /dev/null +++ b/gdb/bsd-kvm.h @@ -0,0 +1,35 @@ +/* BSD Kernel Data Access Library (libkvm) interface. + + Copyright 2004 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#ifndef BSD_KVM_H +#define BSD_KVM_H + +struct pcb; +struct regcache; + +/* Add the libkvm interface to the list of all possible targets and + register CUPPLY_PCB as the architecture-specific process control + block interpreter. */ + +extern void + bsd_kvm_add_target (int (*supply_pcb)(struct regcache *, struct pcb *)); + +#endif /* bsd-kvm.h */ diff --git a/gdb/config/i386/fbsd.mh b/gdb/config/i386/fbsd.mh index 2d0500e..8800b21 100644 --- a/gdb/config/i386/fbsd.mh +++ b/gdb/config/i386/fbsd.mh @@ -1,5 +1,8 @@ # Host: FreeBSD/i386 NATDEPFILES= fork-child.o infptrace.o inftarg.o \ - i386-nat.o i386bsd-nat.o i386fbsd-nat.o gcore.o fbsd-proc.o + i386-nat.o i386bsd-nat.o i386fbsd-nat.o \ + gcore.o fbsd-proc.o bsd-kvm.o NAT_FILE= nm-fbsd.h XM_FILE= xm-i386.h + +LOADLIBES= -lkvm diff --git a/gdb/i386fbsd-nat.c b/gdb/i386fbsd-nat.c index efc61b6..ed07711 100644 --- a/gdb/i386fbsd-nat.c +++ b/gdb/i386fbsd-nat.c @@ -29,9 +29,6 @@ #include "i386-tdep.h" -/* Prevent warning from -Wmissing-prototypes. */ -void _initialize_i386fbsd_nat (void); - /* Resume execution of the inferior process. If STEP is nonzero, single-step it. If SIGNAL is nonzero, give it that signal. */ @@ -79,6 +76,46 @@ child_resume (ptid_t ptid, int step, enum target_signal signal) perror_with_name ("ptrace"); } + +/* Support for debugging kernel virtual memory images. */ + +#include +#include + +#include "bsd-kvm.h" + +static int +i386fbsd_supply_pcb (struct regcache *regcache, struct pcb *pcb) +{ + /* The following is true for FreeBSD 4.7: + + The pcb contains %eip, %ebx, %esp, %ebp, %esi, %edi and %gs. + This accounts for all callee-saved registers specified by the + psABI and then some. Here %esp contains the stack pointer at the + point just after the call to cpu_switch(). From this information + we reconstruct the register state as it would look when we just + returned from cpu_switch(). */ + + /* The stack pointer shouldn't be zero. */ + if (pcb->pcb_esp == 0) + return 0; + + pcb->pcb_esp += 4; + regcache_raw_supply (regcache, I386_EDI_REGNUM, &pcb->pcb_edi); + regcache_raw_supply (regcache, I386_ESI_REGNUM, &pcb->pcb_esi); + regcache_raw_supply (regcache, I386_EBP_REGNUM, &pcb->pcb_ebp); + regcache_raw_supply (regcache, I386_ESP_REGNUM, &pcb->pcb_esp); + regcache_raw_supply (regcache, I386_EBX_REGNUM, &pcb->pcb_ebx); + regcache_raw_supply (regcache, I386_EIP_REGNUM, &pcb->pcb_eip); + regcache_raw_supply (regcache, I386_GS_REGNUM, &pcb->pcb_gs); + + return 1; +} + + +/* Prevent warning from -Wmissing-prototypes. */ +void _initialize_i386fbsd_nat (void); + void _initialize_i386fbsd_nat (void) { @@ -104,4 +141,7 @@ _initialize_i386fbsd_nat (void) } } #endif + + /* Support debugging kernel virtual memory images. */ + bsd_kvm_add_target (i386fbsd_supply_pcb); } -- 2.7.4