diff --git a/devel/gdb/files/kgdb/fbsd-kvm.c b/devel/gdb/files/kgdb/fbsd-kvm.c index b5bc0f924612..bd4f71fecddd 100644 --- a/devel/gdb/files/kgdb/fbsd-kvm.c +++ b/devel/gdb/files/kgdb/fbsd-kvm.c @@ -1,613 +1,639 @@ /* * 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 AUTHOR ``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 AUTHOR 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 "defs.h" #include "command.h" #include "elf-bfd.h" #include "filenames.h" #include "gdbcore.h" #include "gdbthread.h" #include "gdbsupport/gdb_obstack.h" #include "inferior.h" #include "objfiles.h" #include "osabi.h" #include "process-stratum-target.h" #include "solib.h" #include "target.h" #include "value.h" #include "readline/tilde.h" #include "gdbsupport/buildargv.h" #include "gdbsupport/pathstuff.h" #include "gdbsupport/gdb_tilde_expand.h" #include #include #include #include "kgdb.h" static CORE_ADDR stoppcbs; static LONGEST pcb_size; static std::string vmcore; struct fbsd_vmcore_ops { /* Supply registers for a pcb to a register cache. */ void (*supply_pcb)(struct regcache *, CORE_ADDR) = nullptr; /* Return address of pcb for thread running on a CPU. */ CORE_ADDR (*cpu_pcb_addr)(u_int) = nullptr; }; /* Per-architecture data key. */ static const registry::key fbsd_vmcore_data; static struct fbsd_vmcore_ops * get_fbsd_vmcore_ops (struct gdbarch *gdbarch) { struct fbsd_vmcore_ops *ops = fbsd_vmcore_data.get (gdbarch); if (ops == nullptr) ops = fbsd_vmcore_data.emplace (gdbarch); return ops; } /* Set the function that supplies registers from a pcb for architecture GDBARCH to SUPPLY_PCB. */ void fbsd_vmcore_set_supply_pcb (struct gdbarch *gdbarch, void (*supply_pcb) (struct regcache *, CORE_ADDR)) { struct fbsd_vmcore_ops *ops = get_fbsd_vmcore_ops (gdbarch); ops->supply_pcb = supply_pcb; } /* Set the function that returns the address of the pcb for a thread running on a CPU for architecture GDBARCH to CPU_PCB_ADDR. */ void fbsd_vmcore_set_cpu_pcb_addr (struct gdbarch *gdbarch, CORE_ADDR (*cpu_pcb_addr) (u_int)) { struct fbsd_vmcore_ops *ops = get_fbsd_vmcore_ops (gdbarch); ops->cpu_pcb_addr = cpu_pcb_addr; } static CORE_ADDR kernstart; static kvm_t *kvm; int kgdb_quiet; static ptid_t fbsd_vmcore_ptid(int tid) { if (kvm == NULL) /* * The remote target stores the 'tid' in the lwp * field. */ return ptid_t(inferior_ptid.pid(), tid, 0); /* * This follows the model described in bsd-kvm.c except that * in kernel tids are used as the tid of the ptid instead of a * process ID. */ return ptid_t(1, 1, tid); } #define MSGBUF_SEQ_TO_POS(size, seq) ((seq) % (size)) static void kgdb_dmesg(void) { CORE_ADDR bufp; int size, rseq, wseq; gdb_byte c; /* * Display the unread portion of the message buffer. This gives the * user a some initial data to work from. */ if (kgdb_quiet) return; try { bufp = parse_and_eval_address("msgbufp->msg_ptr"); size = parse_and_eval_long("msgbufp->msg_size"); rseq = parse_and_eval_long("msgbufp->msg_rseq"); wseq = parse_and_eval_long("msgbufp->msg_wseq"); } catch (const gdb_exception_error &e) { return; } if (size == 0) return; rseq = MSGBUF_SEQ_TO_POS(size, rseq); wseq = MSGBUF_SEQ_TO_POS(size, wseq); if (rseq == wseq) return; printf("\nUnread portion of the kernel message buffer:\n"); while (rseq < wseq) { read_memory(bufp + rseq, &c, 1); putchar(c); rseq++; if (rseq == size) rseq = 0; } if (c != '\n') putchar('\n'); putchar('\n'); } #define KERNEL_INTERP "/red/herring" enum gdb_osabi fbsd_kernel_osabi_sniffer(bfd *abfd) { asection *s; bfd_byte buf[sizeof(KERNEL_INTERP)]; bfd_byte *bufp; /* First, determine if this is a FreeBSD/ELF binary. */ switch (elf_elfheader(abfd)->e_ident[EI_OSABI]) { case ELFOSABI_FREEBSD: break; case ELFOSABI_NONE: { enum gdb_osabi osabi = GDB_OSABI_UNKNOWN; for (asection *sect : gdb_bfd_sections (abfd)) generic_elf_osabi_sniff_abi_tag_sections (abfd, sect, &osabi); /* * aarch64 and RISC-V kernels don't have the right * note tag for kernels so just look for /red/herring * anyway. */ if (osabi == GDB_OSABI_UNKNOWN && ((elf_elfheader(abfd)->e_machine == EM_AARCH64) || (elf_elfheader(abfd)->e_machine == EM_RISCV))) break; if (osabi != GDB_OSABI_FREEBSD) return (GDB_OSABI_UNKNOWN); break; } default: return (GDB_OSABI_UNKNOWN); } /* FreeBSD ELF kernels have an interpreter path of "/red/herring". */ bufp = buf; s = bfd_get_section_by_name(abfd, ".interp"); if (s != NULL && bfd_section_size(s) == sizeof(buf) && bfd_get_full_section_contents(abfd, s, &bufp) && memcmp(buf, KERNEL_INTERP, sizeof(buf)) == 0) return (GDB_OSABI_FREEBSD_KERNEL); return (GDB_OSABI_UNKNOWN); } /* The FreeBSD libkvm target. */ static const target_info fbsd_kvm_target_info = { "vmcore", N_("Kernel core dump file"), N_("Use a vmcore file as a target.\n\ If no filename is specified, /dev/mem is used to examine the running kernel.\n\ target vmcore [-w] [filename]") }; class fbsd_kvm_target final : public process_stratum_target { public: fbsd_kvm_target () = default; const target_info &info () const override { return fbsd_kvm_target_info; } void close () override; void fetch_registers (struct regcache *, int) override; enum target_xfer_status xfer_partial (enum target_object object, const char *annex, gdb_byte *readbuf, const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, ULONGEST *xfered_len) override; void files_info () override; bool thread_alive (ptid_t ptid) override; std::string pid_to_str (ptid_t) override; const char *extra_thread_info (thread_info *) override; bool has_all_memory () override { return false; } bool has_memory () override; bool has_stack () override; bool has_registers () override; bool has_execution (inferior *inf) override { return false; } }; /* Target ops for libkvm interface. */ static fbsd_kvm_target fbsd_kvm_ops; #ifdef HAVE_KVM_OPEN2 static int kgdb_resolve_symbol(const char *name, kvaddr_t *kva) { struct bound_minimal_symbol ms; ms = lookup_minimal_symbol (name, NULL, NULL); if (ms.minsym == NULL) return (1); *kva = ms.value_address (); return (0); } #endif static void fbsd_kvm_target_open (const char *args, int from_tty) { struct fbsd_vmcore_ops *ops = get_fbsd_vmcore_ops (target_gdbarch ()); char kvm_err[_POSIX2_LINE_MAX]; struct inferior *inf; struct cleanup *old_chain; struct kthr *kt; kvm_t *nkvm; const char *kernel; std::string filename; + int osreldate; bool writeable; if (ops == NULL || ops->supply_pcb == NULL || ops->cpu_pcb_addr == NULL) error ("ABI doesn't support a vmcore target"); target_preopen (from_tty); kernel = get_exec_file (0); if (kernel == NULL) error ("Can't open a vmcore without a kernel"); writeable = false; if (args != NULL) { gdb_argv built_argv (args); for (char **argv = built_argv.get (); *argv != NULL; argv++) { if (**argv == '-') { if (strcmp (*argv, "-w") == 0) writeable = true; else error (_("Invalid argument")); } else { if (!filename.empty ()) error (_("Invalid argument")); filename = gdb_tilde_expand (*argv); if (!IS_ABSOLUTE_PATH (filename)) filename = gdb_abspath (filename.c_str ()); } } } #ifdef HAVE_KVM_OPEN2 nkvm = kvm_open2(kernel, filename.c_str (), writeable ? O_RDWR : O_RDONLY, kvm_err, kgdb_resolve_symbol); #else nkvm = kvm_openfiles(kernel, filename.c_str (), NULL, writeable ? O_RDWR : O_RDONLY, kvm_err); #endif if (nkvm == NULL) { error ("Failed to open vmcore: %s", kvm_err); } /* Don't free the filename now and close any previous vmcore. */ current_inferior ()->unpush_target (&fbsd_kvm_ops); #ifdef HAVE_KVM_DISP /* Relocate kernel objfile if needed. */ struct objfile *symfile_objfile = current_program_space->symfile_object_file; if (symfile_objfile != nullptr && (bfd_get_file_flags(symfile_objfile->obfd.get ()) & (EXEC_P | DYNAMIC)) != 0) { CORE_ADDR displacement = kvm_kerndisp(nkvm); if (displacement != 0) { section_offsets new_offsets (symfile_objfile->section_offsets.size (), displacement); objfile_relocate(symfile_objfile, new_offsets); } } #endif + kvm = nkvm; + vmcore = std::move(filename); + current_inferior()->push_target (&fbsd_kvm_ops); + + /* Pop the target automatically upon failure. */ + target_unpush_up unpusher; + unpusher.reset (&fbsd_kvm_ops); + /* * Determine the first address in KVA. Newer kernels export * VM_MAXUSER_ADDRESS and the first kernel address can be * determined by adding one. Older kernels do not provide a * symbol that is valid on all platforms, but kernbase is close * for most platforms. */ try { kernstart = parse_and_eval_address("vm_maxuser_address") + 1; } catch (const gdb_exception_error &e) { kernstart = kgdb_lookup("kernbase"); } + try { + CORE_ADDR osreldatesym = kgdb_lookup("osreldate"); + osreldate = read_memory_unsigned_integer(osreldatesym, 4, + gdbarch_byte_order (target_gdbarch ())); + } catch (const gdb_exception_error &e) { + error ("Failed to look up osreldate"); + } + /* - * Lookup symbols needed for stoppcbs[] handling, but don't + * Look up symbols needed for stoppcbs handling, but don't * fail if they aren't present. */ stoppcbs = kgdb_lookup("stoppcbs"); + if (osreldate > 1400088) { + /* stoppcbs is now a pointer rather than an array. */ + try { + stoppcbs = read_memory_typed_address(stoppcbs, + builtin_type(target_gdbarch())->builtin_data_ptr); + } catch (const gdb_exception_error &e) { + stoppcbs = 0; + } + } + try { pcb_size = parse_and_eval_long("pcb_size"); } catch (const gdb_exception_error &e) { pcb_size = 0; } if (pcb_size == 0) { try { pcb_size = parse_and_eval_long("sizeof(struct pcb)"); } catch (const gdb_exception_error &e) { #ifdef HAVE_KVM_OPEN2 if (kvm_native(nkvm)) pcb_size = sizeof(struct pcb); else pcb_size = 0; #else pcb_size = sizeof(struct pcb); #endif } } - kvm = nkvm; - vmcore = std::move(filename); - current_inferior()->push_target (&fbsd_kvm_ops); - kgdb_dmesg(); inf = current_inferior(); if (inf->pid == 0) { inferior_appeared(inf, 1); inf->fake_pid_p = 1; } solib_create_inferior_hook(0); kt = kgdb_thr_init(ops->cpu_pcb_addr); thread_info *curthr = nullptr; while (kt != NULL) { thread_info *thr = add_thread_silent(&fbsd_kvm_ops, fbsd_vmcore_ptid(kt->tid)); if (kt == curkthr) curthr = thr; kt = kgdb_thr_next(kt); } switch_to_thread (curthr); target_fetch_registers (get_current_regcache (), -1); reinit_frame_cache (); print_stack_frame (get_selected_frame (NULL), 0, SRC_AND_LOC, 1); + + /* Keep the target pushed. */ + unpusher.release (); } void fbsd_kvm_target::close() { if (kvm != NULL) { switch_to_no_thread (); exit_inferior_silent (current_inferior ()); clear_solib(); if (kvm_close(kvm) != 0) warning("cannot close \"%s\": %s", vmcore.c_str (), kvm_geterr(kvm)); kvm = NULL; vmcore.clear (); } } #if 0 static void kgdb_trgt_detach(struct target_ops *ops, const char *args, int from_tty) { if (args) error ("Too many arguments"); unpush_target(&kgdb_trgt_ops); reinit_frame_cache(); if (from_tty) gdb_printf("No vmcore file now.\n"); } #endif const char * fbsd_kvm_target::extra_thread_info(thread_info *ti) { return (kgdb_thr_extra_thread_info(ti->ptid.tid())); } bool fbsd_kvm_target::has_memory () { return (kvm != NULL); } bool fbsd_kvm_target::has_stack () { return (kvm != NULL); } bool fbsd_kvm_target::has_registers () { return (kvm != NULL); } void fbsd_kvm_target::files_info() { gdb_printf ("\t`%s', ", vmcore.c_str ()); gdb_stdout->wrap_here (8); gdb_printf ("file type %s.\n", "FreeBSD kernel vmcore"); } std::string fbsd_kvm_target::pid_to_str(ptid_t ptid) { return string_printf (_("Thread %ld"), ptid.tid ()); } bool fbsd_kvm_target::thread_alive(ptid_t ptid) { return (kgdb_thr_lookup_tid(ptid.tid()) != NULL); } void fbsd_kvm_target::fetch_registers(struct regcache *regcache, int regnum) { struct fbsd_vmcore_ops *ops = get_fbsd_vmcore_ops (target_gdbarch ()); struct kthr *kt; if (ops->supply_pcb == NULL) return; kt = kgdb_thr_lookup_tid(regcache->ptid().tid()); if (kt == NULL) return; ops->supply_pcb(regcache, kt->pcb); } enum target_xfer_status fbsd_kvm_target::xfer_partial(enum target_object object, const char *annex, gdb_byte *readbuf, const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, ULONGEST *xfered_len) { ssize_t nbytes; gdb_assert(kvm != NULL); switch (object) { case TARGET_OBJECT_MEMORY: nbytes = len; if (readbuf != NULL) #ifdef HAVE_KVM_OPEN2 nbytes = kvm_read2(kvm, offset, readbuf, len); #else nbytes = kvm_read(kvm, offset, readbuf, len); #endif if (writebuf != NULL && len > 0) nbytes = kvm_write(kvm, offset, writebuf, len); if (nbytes < 0) return TARGET_XFER_E_IO; if (nbytes == 0) return TARGET_XFER_EOF; *xfered_len = nbytes; return TARGET_XFER_OK; default: return TARGET_XFER_E_IO; } } static void kgdb_switch_to_thread(const char *arg, int tid) { struct thread_info *tp; tp = find_thread_ptid (&fbsd_kvm_ops, fbsd_vmcore_ptid (tid)); if (tp == NULL) error ("invalid tid"); thread_select (arg, tp); } static void kgdb_set_proc_cmd (const char *arg, int from_tty) { CORE_ADDR addr; struct kthr *thr; if (!arg) error_no_arg ("proc address for the new context"); if (kvm == NULL) error ("only supported for core file target"); addr = parse_and_eval_address (arg); if (addr < kernstart) { thr = kgdb_thr_lookup_pid((int)addr); if (thr == NULL) error ("invalid pid"); } else { thr = kgdb_thr_lookup_paddr(addr); if (thr == NULL) error("invalid proc address"); } kgdb_switch_to_thread(arg, thr->tid); } static void kgdb_set_tid_cmd (const char *arg, int from_tty) { CORE_ADDR addr; struct kthr *thr; if (!arg) error_no_arg ("TID or thread address for the new context"); addr = (CORE_ADDR) parse_and_eval_address (arg); if (kvm != NULL && addr >= kernstart) { thr = kgdb_thr_lookup_taddr(addr); if (thr == NULL) error("invalid thread address"); addr = thr->tid; } kgdb_switch_to_thread(arg, addr); } void _initialize_kgdb_target (); void _initialize_kgdb_target () { add_target(fbsd_kvm_target_info, fbsd_kvm_target_open, filename_completer); add_com ("proc", class_obscure, kgdb_set_proc_cmd, "Set current process context"); add_com ("tid", class_obscure, kgdb_set_tid_cmd, "Set current thread context"); } CORE_ADDR kgdb_trgt_stop_pcb(u_int cpuid) { if (stoppcbs == 0 || pcb_size == 0) return 0; return (stoppcbs + pcb_size * cpuid); }