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This patch fixes hardware breakpoint regressions exposed by my fix for "PR breakpoints/7143 - Watchpoint does not trigger when first set", at https://sourceware.org/ml/gdb-patches/2014-03/msg00167.html The testsuite caught them on Linux/x86_64, at least. gdb.sum: gdb.sum: FAIL: gdb.base/hbreak2.exp: next over recursive call FAIL: gdb.base/hbreak2.exp: backtrace from factorial(5.1) FAIL: gdb.base/hbreak2.exp: continue until exit at recursive next test gdb.log: (gdb) next Program received signal SIGTRAP, Trace/breakpoint trap. factorial (value=4) at ../../../src/gdb/testsuite/gdb.base/break.c:113 113 if (value > 1) { /* set breakpoint 7 here */ (gdb) FAIL: gdb.base/hbreak2.exp: next over recursive call Actually, that patch just exposed a latent issue to "breakpoints always-inserted off" mode, not really caused it. After that patch, GDB no longer removes breakpoints at each internal event, thus making some scenarios behave like breakpoint always-inserted on. The bug is easy to trigger with always-inserted on. The issue is that since the target-side breakpoint conditions support, if the stub/server supports evaluating breakpoint conditions on the target side, then GDB is sending duplicate Zx packets to the target without removing them before, and GDBserver is not really expecting that for Z packets other than Z0/z0. E.g., with "set breakpoint always-inserted on" and "set debug remote 1": (gdb) b main Sending packet: $m410943,1#ff...Packet received: 48 Breakpoint 4 at 0x410943: file ../../../src/gdb/gdbserver/server.c, line 3028. Sending packet: $Z0,410943,1#48...Packet received: OK ^^^^^^^^^^^^ (gdb) b main Note: breakpoint 4 also set at pc 0x410943. Sending packet: $m410943,1#ff...Packet received: 48 Breakpoint 5 at 0x410943: file ../../../src/gdb/gdbserver/server.c, line 3028. Sending packet: $Z0,410943,1#48...Packet received: OK ^^^^^^^^^^^^ (gdb) b main Note: breakpoints 4 and 5 also set at pc 0x410943. Sending packet: $m410943,1#ff...Packet received: 48 Breakpoint 6 at 0x410943: file ../../../src/gdb/gdbserver/server.c, line 3028. Sending packet: $Z0,410943,1#48...Packet received: OK ^^^^^^^^^^^^ (gdb) del Delete all breakpoints? (y or n) y Sending packet: $Z0,410943,1#48...Packet received: OK Sending packet: $Z0,410943,1#48...Packet received: OK Sending packet: $z0,410943,1#68...Packet received: OK And for Z1, similarly: (gdb) hbreak main Sending packet: $m410943,1#ff...Packet received: 48 Hardware assisted breakpoint 4 at 0x410943: file ../../../src/gdb/gdbserver/server.c, line 3028. Sending packet: $Z1,410943,1#49...Packet received: OK ^^^^^^^^^^^^ Packet Z1 (hardware-breakpoint) is supported (gdb) hbreak main Note: breakpoint 4 also set at pc 0x410943. Sending packet: $m410943,1#ff...Packet received: 48 Hardware assisted breakpoint 5 at 0x410943: file ../../../src/gdb/gdbserver/server.c, line 3028. Sending packet: $Z1,410943,1#49...Packet received: OK ^^^^^^^^^^^^ (gdb) hbreak main Note: breakpoints 4 and 5 also set at pc 0x410943. Sending packet: $m410943,1#ff...Packet received: 48 Hardware assisted breakpoint 6 at 0x410943: file ../../../src/gdb/gdbserver/server.c, line 3028. Sending packet: $Z1,410943,1#49...Packet received: OK ^^^^^^^^^^^^ (gdb) del Delete all breakpoints? (y or n) y Sending packet: $Z1,410943,1#49...Packet received: OK ^^^^^^^^^^^^ Sending packet: $Z1,410943,1#49...Packet received: OK ^^^^^^^^^^^^ Sending packet: $z1,410943,1#69...Packet received: OK ^^^^^^^^^^^^ So GDB sent a bunch of Z1 packets, and then when finally removing the breakpoint, only one z1 packet was sent. On the GDBserver side (with monitor set debug-hw-points 1), in the Z1 case, we see: $ ./gdbserver :9999 ./gdbserver Process ./gdbserver created; pid = 8629 Listening on port 9999 Remote debugging from host 127.0.0.1 insert_watchpoint (addr=410943, len=1, type=instruction-execute): CONTROL (DR7): 00000101 STATUS (DR6): 00000000 DR0: addr=0x410943, ref.count=1 DR1: addr=0x0, ref.count=0 DR2: addr=0x0, ref.count=0 DR3: addr=0x0, ref.count=0 insert_watchpoint (addr=410943, len=1, type=instruction-execute): CONTROL (DR7): 00000101 STATUS (DR6): 00000000 DR0: addr=0x410943, ref.count=2 DR1: addr=0x0, ref.count=0 DR2: addr=0x0, ref.count=0 DR3: addr=0x0, ref.count=0 insert_watchpoint (addr=410943, len=1, type=instruction-execute): CONTROL (DR7): 00000101 STATUS (DR6): 00000000 DR0: addr=0x410943, ref.count=3 DR1: addr=0x0, ref.count=0 DR2: addr=0x0, ref.count=0 DR3: addr=0x0, ref.count=0 insert_watchpoint (addr=410943, len=1, type=instruction-execute): CONTROL (DR7): 00000101 STATUS (DR6): 00000000 DR0: addr=0x410943, ref.count=4 DR1: addr=0x0, ref.count=0 DR2: addr=0x0, ref.count=0 DR3: addr=0x0, ref.count=0 insert_watchpoint (addr=410943, len=1, type=instruction-execute): CONTROL (DR7): 00000101 STATUS (DR6): 00000000 DR0: addr=0x410943, ref.count=5 DR1: addr=0x0, ref.count=0 DR2: addr=0x0, ref.count=0 DR3: addr=0x0, ref.count=0 remove_watchpoint (addr=410943, len=1, type=instruction-execute): CONTROL (DR7): 00000101 STATUS (DR6): 00000000 DR0: addr=0x410943, ref.count=4 DR1: addr=0x0, ref.count=0 DR2: addr=0x0, ref.count=0 DR3: addr=0x0, ref.count=0 That's one insert_watchpoint call for each Z1 packet, and then one remove_watchpoint call for the z1 packet. Notice how ref.count increased for each insert_watchpoint call, and then in the end, after GDB told GDBserver to forget about the hardware breakpoint, GDBserver ends with the the first debug register still with ref.count=4! IOW, the hardware breakpoint is left armed on the target, while on the GDB end it's gone. If the program happens to execute 0x410943 afterwards, then the CPU traps, GDBserver reports the trap to GDB, and GDB not having a breakpoint set at that address anymore, reports to the user a spurious SIGTRAP. This is exactly what is happening in the hbreak2.exp test, though in that case, it's a shared library event that triggers a breakpoint_re_set, when breakpoints are still inserted (because nowadays GDB doesn't remove breakpoints while handling internal events), and that recreates breakpoint locations, which likewise forces breakpoint reinsertion and Zx packet resends... That is a lot of bogus Zx duplication that should possibly be addressed on the GDB side. GDB resends Zx packets because the way to change the target-side condition, is to resend the breakpoint to the server with the new condition. (That's an option in the packet: e.g., "Z1,410943,1;X3,220027" for "hbreak main if 0". The packets in the examples above are shorter because the breakpoints don't have conditions attached). GDB doesn't remove the breakpoint first before reinserting it because that'd be bad for non-stop, as it'd open a window where the inferior could miss the breakpoint. The conditions actually haven't changed between the resends, but GDB isn't smart enough to realize that. (TBC, if the target doesn't support target-side conditions, then GDB doesn't trigger these resends (init_bp_location calls mark_breakpoint_location_modified, and that does nothing if condition evaluation is on the host side. The resends are caused by the 'loc->condition_changed = condition_modified.' line.) But, even if GDB was made smarter, GDBserver should really still handle the resends anyway. So target-side conditions also aren't really to blame. The documentation of the Z/z packets says: "To avoid potential problems with duplicate packets, the operations should be implemented in an idempotent way." As such, we may want to fix GDB, but we should definitely fix GDBserver. The fix is a prerequisite for target-side conditions on hardware breakpoints anyway (and while at it, on watchpoints too). GDBserver indeed already treats duplicate Z0 packets in an idempotent way. mem-break.c has the concept of high-level and low-level breakpoints, somewhat similar to GDB's split of breakpoints vs breakpoint locations, and keeps track of multiple breakpoints referencing the same address/location, for the case of an internal GDBserver breakpoint or a tracepoint being set at the same address as a GDB breakpoint. But, it only allows GDB to ever contribute one reference to a software breakpoint location. IOW, if gdbserver sees a Z0 packet for the same address where it already had a GDB breakpoint set, then GDBserver won't create another high-level GDB breakpoint. However, mem-break.c only tracks GDB Z0 breakpoints. The same logic should apply to all kinds of Zx packets. Currently, gdbserver passes down each duplicate Zx (other than Z0) request directly to the target->insert_point routine. The x86 watchpoint support itself refcounts watchpoint / hw breakpoint requests, to handle overlapping watchpoints, and save debug registers. But that code doesn't (and really shouldn't) handle the duplicate requests, assuming that for each insert there will be a corresponding remove. So the fix is to generalize mem-break.c to track all kinds of Zx breakpoints, and filter out duplicates. As mentioned, this ends up adding support for target-side conditions on hardware breakpoints and watchpoints too (though GDB itself doesn't support the latter yet). Probably the least obvious change in the patch is that it kind of turns the breakpoint insert/remove APIs inside out. Before, the target methods were only called for GDB breakpoints. The internal breakpoint set/delete methods inserted memory breakpoints directly bypassing the insert/remove target methods. That's not good when the target should use a debug API to set software breakpoints, instead of relying on GDBserver patching memory with breakpoint instructions, as is the case of NTO. Now removal/insertion of all kinds of breakpoints/watchpoints, either internal, or from GDB, always go through the target methods. The insert_point/remove_point methods no longer get passed a Z packet type, but an internal/raw breakpoint type. They're also passed a pointer to the raw breakpoint itself (note that's still opaque outside mem-break.c), so that insert_memory_breakpoint / remove_memory_breakpoint have access to the breakpoint's shadow buffer. I first tried passing down a new structure based on GDB's "struct bp_target_info" (actually with that name exactly), but then decided against it as unnecessary complication. As software/memory breakpoints work by poking at memory, when setting a GDB Z0 breakpoint (but not internal breakpoints, as those can assume the conditions are already right), we need to tell the target to prepare to access memory (which on Linux means stop threads). If that operation fails, we need to return error to GDB. Seeing an error, if this is the first breakpoint of that type that GDB tries to insert, GDB would then assume the breakpoint type is supported, but it may actually not be. So we need to check whether the type is supported at all before preparing to access memory. And to solve that, the patch adds a new target->supports_z_point_type method that is called before actually trying to insert the breakpoint. Other than that, hopefully the change is more or less obvious. New test added that exercises the hbreak2.exp regression in a more direct way, without relying on a breakpoint re-set happening before main is reached. Tested by building GDBserver for: aarch64-linux-gnu arm-linux-gnueabihf i686-pc-linux-gnu i686-w64-mingw32 m68k-linux-gnu mips-linux-gnu mips-uclinux nios2-linux-gnu powerpc-linux-gnu sh-linux-gnu tilegx-unknown-linux-gnu x86_64-redhat-linux x86_64-w64-mingw32 And also regression tested on x86_64 Fedora 20. gdb/gdbserver/ 2014-05-20 Pedro Alves <palves@redhat.com> * linux-aarch64-low.c (aarch64_insert_point) (aarch64_remove_point): No longer check whether the type is supported here. Adjust to new interface. (the_low_target): Install aarch64_supports_z_point_type as supports_z_point_type method. * linux-arm-low.c (raw_bkpt_type_to_arm_hwbp_type): New function. (arm_linux_hw_point_initialize): Take an enum raw_bkpt_type instead of a Z packet char. Adjust. (arm_supports_z_point_type): New function. (arm_insert_point, arm_remove_point): Adjust to new interface. (the_low_target): Install arm_supports_z_point_type. * linux-crisv32-low.c (cris_supports_z_point_type): New function. (cris_insert_point, cris_remove_point): Adjust to new interface. Don't check whether the type is supported here. (the_low_target): Install cris_supports_z_point_type. * linux-low.c (linux_supports_z_point_type): New function. (linux_insert_point, linux_remove_point): Adjust to new interface. * linux-low.h (struct linux_target_ops) <insert_point, remove_point>: Take an enum raw_bkpt_type instead of a char. Add raw_breakpoint pointer parameter. <supports_z_point_type>: New method. * linux-mips-low.c (mips_supports_z_point_type): New function. (mips_insert_point, mips_remove_point): Adjust to new interface. Use mips_supports_z_point_type. (the_low_target): Install mips_supports_z_point_type. * linux-ppc-low.c (the_low_target): Install NULL as supports_z_point_type method. * linux-s390-low.c (the_low_target): Install NULL as supports_z_point_type method. * linux-sparc-low.c (the_low_target): Install NULL as supports_z_point_type method. * linux-x86-low.c (x86_supports_z_point_type): New function. (x86_insert_point): Adjust to new insert_point interface. Use insert_memory_breakpoint. Adjust to new i386_low_insert_watchpoint interface. (x86_remove_point): Adjust to remove_point interface. Use remove_memory_breakpoint. Adjust to new i386_low_remove_watchpoint interface. (the_low_target): Install x86_supports_z_point_type. * lynx-low.c (lynx_target_ops): Install NULL as supports_z_point_type callback. * nto-low.c (nto_supports_z_point_type): New. (nto_insert_point, nto_remove_point): Adjust to new interface. (nto_target_ops): Install nto_supports_z_point_type. * mem-break.c: Adjust intro comment. (struct raw_breakpoint) <raw_type, size>: New fields. <inserted>: Update comment. <shlib_disabled>: Delete field. (enum bkpt_type) <gdb_breakpoint>: Delete value. <gdb_breakpoint_Z0, gdb_breakpoint_Z1, gdb_breakpoint_Z2, gdb_breakpoint_Z3, gdb_breakpoint_Z4>: New values. (raw_bkpt_type_to_target_hw_bp_type): New function. (find_enabled_raw_code_breakpoint_at): New function. (find_raw_breakpoint_at): New type and size parameters. Use them. (insert_memory_breakpoint): New function, based off set_raw_breakpoint_at. (remove_memory_breakpoint): New function. (set_raw_breakpoint_at): Reimplement. (set_breakpoint): New, based on set_breakpoint_at. (set_breakpoint_at): Reimplement. (delete_raw_breakpoint): Go through the_target->remove_point instead of assuming memory breakpoints. (find_gdb_breakpoint_at): Delete. (Z_packet_to_bkpt_type, Z_packet_to_raw_bkpt_type): New functions. (find_gdb_breakpoint): New function. (set_gdb_breakpoint_at): Delete. (z_type_supported): New function. (set_gdb_breakpoint_1): New function, loosely based off set_gdb_breakpoint_at. (check_gdb_bp_preconditions, set_gdb_breakpoint): New functions. (delete_gdb_breakpoint_at): Delete. (delete_gdb_breakpoint_1): New function, loosely based off delete_gdb_breakpoint_at. (delete_gdb_breakpoint): New function. (clear_gdb_breakpoint_conditions): Rename to ... (clear_breakpoint_conditions): ... this. Don't handle a NULL breakpoint. (add_condition_to_breakpoint): Make static. (add_breakpoint_condition): Take a struct breakpoint pointer instead of an address. Adjust. (gdb_condition_true_at_breakpoint): Rename to ... (gdb_condition_true_at_breakpoint_z_type): ... this, and add z_type parameter. (gdb_condition_true_at_breakpoint): Reimplement. (add_breakpoint_commands): Take a struct breakpoint pointer instead of an address. Adjust. (gdb_no_commands_at_breakpoint): Rename to ... (gdb_no_commands_at_breakpoint_z_type): ... this. Add z_type parameter. Return true if no breakpoint was found. Change debug output. (gdb_no_commands_at_breakpoint): Reimplement. (run_breakpoint_commands): Rename to ... (run_breakpoint_commands_z_type): ... this. Add z_type parameter, and change return type to boolean. (run_breakpoint_commands): New function. (gdb_breakpoint_here): Also check for Z1 breakpoints. (uninsert_raw_breakpoint): Don't try to reinsert a disabled breakpoint. Go through the_target->remove_point instead of assuming memory breakpoint. (uninsert_breakpoints_at, uninsert_all_breakpoints): Uninsert software and hardware breakpoints. (reinsert_raw_breakpoint): Go through the_target->insert_point instead of assuming memory breakpoint. (reinsert_breakpoints_at, reinsert_all_breakpoints): Reinsert software and hardware breakpoints. (check_breakpoints, breakpoint_here, breakpoint_inserted_here): Check both software and hardware breakpoints. (validate_inserted_breakpoint): Assert the breakpoint is a software breakpoint. Set the inserted flag to -1 instead of setting shlib_disabled. (delete_disabled_breakpoints): Adjust. (validate_breakpoints): Only validate software breakpoints. Adjust to inserted flag change. (check_mem_read, check_mem_write): Skip breakpoint types other than software breakpoints. Adjust to inserted flag change. * mem-break.h (enum raw_bkpt_type): New enum. (raw_breakpoint, struct process_info): Forward declare. (Z_packet_to_target_hw_bp_type): Delete declaration. (raw_bkpt_type_to_target_hw_bp_type, Z_packet_to_raw_bkpt_type) (set_gdb_breakpoint, delete_gdb_breakpoint) (clear_breakpoint_conditions): New declarations. (set_gdb_breakpoint_at, clear_gdb_breakpoint_conditions): Delete. (breakpoint_inserted_here): Update comment. (add_breakpoint_condition, add_breakpoint_commands): Replace address parameter with a breakpoint pointer parameter. (gdb_breakpoint_here): Update comment. (delete_gdb_breakpoint_at): Delete. (insert_memory_breakpoint, remove_memory_breakpoint): Declare. * server.c (process_point_options): Take a struct breakpoint pointer instead of an address. Adjust. (process_serial_event) <Z/z packets>: Use set_gdb_breakpoint and delete_gdb_breakpoint. * spu-low.c (spu_target_ops): Install NULL as supports_z_point_type method. * target.h: Include mem-break.h. (struct target_ops) <prepare_to_access_memory>: Update comment. <supports_z_point_type>: New field. <insert_point, remove_point>: Take an enum raw_bkpt_type argument instead of a char. Also take a raw breakpoint pointer. * win32-arm-low.c (the_low_target): Install NULL as supports_z_point_type. * win32-i386-low.c (i386_supports_z_point_type): New function. (i386_insert_point, i386_remove_point): Adjust to new interface. (the_low_target): Install i386_supports_z_point_type. * win32-low.c (win32_supports_z_point_type): New function. (win32_insert_point, win32_remove_point): Adjust to new interface. (win32_target_ops): Install win32_supports_z_point_type. * win32-low.h (struct win32_target_ops): <supports_z_point_type>: New method. <insert_point, remove_point>: Take an enum raw_bkpt_type argument instead of a char. Also take a raw breakpoint pointer. gdb/testsuite/ 2014-05-20 Pedro Alves <palves@redhat.com> * gdb.base/break-idempotent.c: New file. * gdb.base/break-idempotent.exp: New file.
376 lines
13 KiB
C
376 lines
13 KiB
C
/* Internal interfaces for the GNU/Linux specific target code for gdbserver.
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Copyright (C) 2002-2014 Free Software Foundation, Inc.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>. */
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#include "gdb_thread_db.h"
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#include <signal.h>
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#include "gdbthread.h"
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#include "gdb_proc_service.h"
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/* Included for ptrace type definitions. */
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#include "linux-ptrace.h"
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#define PTRACE_XFER_TYPE long
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#ifdef HAVE_LINUX_REGSETS
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typedef void (*regset_fill_func) (struct regcache *, void *);
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typedef void (*regset_store_func) (struct regcache *, const void *);
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enum regset_type {
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GENERAL_REGS,
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FP_REGS,
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EXTENDED_REGS,
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};
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struct regset_info
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{
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int get_request, set_request;
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/* If NT_TYPE isn't 0, it will be passed to ptrace as the 3rd
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argument and the 4th argument should be "const struct iovec *". */
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int nt_type;
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int size;
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enum regset_type type;
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regset_fill_func fill_function;
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regset_store_func store_function;
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};
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/* Aggregation of all the supported regsets of a given
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architecture/mode. */
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struct regsets_info
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{
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/* The regsets array. */
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struct regset_info *regsets;
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/* The number of regsets in the REGSETS array. */
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int num_regsets;
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/* If we get EIO on a regset, do not try it again. Note the set of
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supported regsets may depend on processor mode on biarch
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machines. This is a (lazily allocated) array holding one boolean
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byte (0/1) per regset, with each element corresponding to the
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regset in the REGSETS array above at the same offset. */
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char *disabled_regsets;
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};
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#endif
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/* Mapping between the general-purpose registers in `struct user'
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format and GDB's register array layout. */
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struct usrregs_info
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{
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/* The number of registers accessible. */
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int num_regs;
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/* The registers map. */
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int *regmap;
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};
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/* All info needed to access an architecture/mode's registers. */
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struct regs_info
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{
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/* Regset support bitmap: 1 for registers that are transferred as a part
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of a regset, 0 for ones that need to be handled individually. This
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can be NULL if all registers are transferred with regsets or regsets
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are not supported. */
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unsigned char *regset_bitmap;
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/* Info used when accessing registers with PTRACE_PEEKUSER /
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PTRACE_POKEUSER. This can be NULL if all registers are
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transferred with regsets .*/
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struct usrregs_info *usrregs;
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#ifdef HAVE_LINUX_REGSETS
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/* Info used when accessing registers with regsets. */
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struct regsets_info *regsets_info;
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#endif
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};
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struct process_info_private
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{
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/* Arch-specific additions. */
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struct arch_process_info *arch_private;
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/* libthread_db-specific additions. Not NULL if this process has loaded
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thread_db, and it is active. */
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struct thread_db *thread_db;
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/* &_r_debug. 0 if not yet determined. -1 if no PT_DYNAMIC in Phdrs. */
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CORE_ADDR r_debug;
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/* This flag is true iff we've just created or attached to the first
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LWP of this process but it has not stopped yet. As soon as it
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does, we need to call the low target's arch_setup callback. */
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int new_inferior;
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};
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struct lwp_info;
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struct linux_target_ops
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{
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/* Architecture-specific setup. */
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void (*arch_setup) (void);
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const struct regs_info *(*regs_info) (void);
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int (*cannot_fetch_register) (int);
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/* Returns 0 if we can store the register, 1 if we can not
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store the register, and 2 if failure to store the register
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is acceptable. */
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int (*cannot_store_register) (int);
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/* Hook to fetch a register in some non-standard way. Used for
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example by backends that have read-only registers with hardcoded
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values (e.g., IA64's gr0/fr0/fr1). Returns true if register
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REGNO was supplied, false if not, and we should fallback to the
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standard ptrace methods. */
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int (*fetch_register) (struct regcache *regcache, int regno);
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CORE_ADDR (*get_pc) (struct regcache *regcache);
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void (*set_pc) (struct regcache *regcache, CORE_ADDR newpc);
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const unsigned char *breakpoint;
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int breakpoint_len;
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CORE_ADDR (*breakpoint_reinsert_addr) (void);
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int decr_pc_after_break;
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int (*breakpoint_at) (CORE_ADDR pc);
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/* Breakpoint and watchpoint related functions. See target.h for
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comments. */
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int (*supports_z_point_type) (char z_type);
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int (*insert_point) (enum raw_bkpt_type type, CORE_ADDR addr,
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int size, struct raw_breakpoint *bp);
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int (*remove_point) (enum raw_bkpt_type type, CORE_ADDR addr,
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int size, struct raw_breakpoint *bp);
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|
int (*stopped_by_watchpoint) (void);
|
|
CORE_ADDR (*stopped_data_address) (void);
|
|
|
|
/* Hooks to reformat register data for PEEKUSR/POKEUSR (in particular
|
|
for registers smaller than an xfer unit). */
|
|
void (*collect_ptrace_register) (struct regcache *regcache,
|
|
int regno, char *buf);
|
|
void (*supply_ptrace_register) (struct regcache *regcache,
|
|
int regno, const char *buf);
|
|
|
|
/* Hook to convert from target format to ptrace format and back.
|
|
Returns true if any conversion was done; false otherwise.
|
|
If DIRECTION is 1, then copy from INF to NATIVE.
|
|
If DIRECTION is 0, copy from NATIVE to INF. */
|
|
int (*siginfo_fixup) (siginfo_t *native, void *inf, int direction);
|
|
|
|
/* Hook to call when a new process is created or attached to.
|
|
If extra per-process architecture-specific data is needed,
|
|
allocate it here. */
|
|
struct arch_process_info * (*new_process) (void);
|
|
|
|
/* Hook to call when a new thread is detected.
|
|
If extra per-thread architecture-specific data is needed,
|
|
allocate it here. */
|
|
struct arch_lwp_info * (*new_thread) (void);
|
|
|
|
/* Hook to call prior to resuming a thread. */
|
|
void (*prepare_to_resume) (struct lwp_info *);
|
|
|
|
/* Hook to support target specific qSupported. */
|
|
void (*process_qsupported) (const char *);
|
|
|
|
/* Returns true if the low target supports tracepoints. */
|
|
int (*supports_tracepoints) (void);
|
|
|
|
/* Fill ADDRP with the thread area address of LWPID. Returns 0 on
|
|
success, -1 on failure. */
|
|
int (*get_thread_area) (int lwpid, CORE_ADDR *addrp);
|
|
|
|
/* Install a fast tracepoint jump pad. See target.h for
|
|
comments. */
|
|
int (*install_fast_tracepoint_jump_pad) (CORE_ADDR tpoint, CORE_ADDR tpaddr,
|
|
CORE_ADDR collector,
|
|
CORE_ADDR lockaddr,
|
|
ULONGEST orig_size,
|
|
CORE_ADDR *jump_entry,
|
|
CORE_ADDR *trampoline,
|
|
ULONGEST *trampoline_size,
|
|
unsigned char *jjump_pad_insn,
|
|
ULONGEST *jjump_pad_insn_size,
|
|
CORE_ADDR *adjusted_insn_addr,
|
|
CORE_ADDR *adjusted_insn_addr_end,
|
|
char *err);
|
|
|
|
/* Return the bytecode operations vector for the current inferior.
|
|
Returns NULL if bytecode compilation is not supported. */
|
|
struct emit_ops *(*emit_ops) (void);
|
|
|
|
/* Return the minimum length of an instruction that can be safely overwritten
|
|
for use as a fast tracepoint. */
|
|
int (*get_min_fast_tracepoint_insn_len) (void);
|
|
|
|
/* Returns true if the low target supports range stepping. */
|
|
int (*supports_range_stepping) (void);
|
|
};
|
|
|
|
extern struct linux_target_ops the_low_target;
|
|
|
|
#define get_thread_lwp(thr) ((struct lwp_info *) (inferior_target_data (thr)))
|
|
#define get_lwp_thread(lwp) ((lwp)->thread)
|
|
|
|
/* This struct is recorded in the target_data field of struct thread_info.
|
|
|
|
On linux ``all_threads'' is keyed by the LWP ID, which we use as the
|
|
GDB protocol representation of the thread ID. Threads also have
|
|
a "process ID" (poorly named) which is (presently) the same as the
|
|
LWP ID.
|
|
|
|
There is also ``all_processes'' is keyed by the "overall process ID",
|
|
which GNU/Linux calls tgid, "thread group ID". */
|
|
|
|
struct lwp_info
|
|
{
|
|
/* Backlink to the parent object. */
|
|
struct thread_info *thread;
|
|
|
|
/* If this flag is set, the next SIGSTOP will be ignored (the
|
|
process will be immediately resumed). This means that either we
|
|
sent the SIGSTOP to it ourselves and got some other pending event
|
|
(so the SIGSTOP is still pending), or that we stopped the
|
|
inferior implicitly via PTRACE_ATTACH and have not waited for it
|
|
yet. */
|
|
int stop_expected;
|
|
|
|
/* When this is true, we shall not try to resume this thread, even
|
|
if last_resume_kind isn't resume_stop. */
|
|
int suspended;
|
|
|
|
/* If this flag is set, the lwp is known to be stopped right now (stop
|
|
event already received in a wait()). */
|
|
int stopped;
|
|
|
|
/* If this flag is set, the lwp is known to be dead already (exit
|
|
event already received in a wait(), and is cached in
|
|
status_pending). */
|
|
int dead;
|
|
|
|
/* When stopped is set, the last wait status recorded for this lwp. */
|
|
int last_status;
|
|
|
|
/* When stopped is set, this is where the lwp stopped, with
|
|
decr_pc_after_break already accounted for. */
|
|
CORE_ADDR stop_pc;
|
|
|
|
/* If this flag is set, STATUS_PENDING is a waitstatus that has not yet
|
|
been reported. */
|
|
int status_pending_p;
|
|
int status_pending;
|
|
|
|
/* STOPPED_BY_WATCHPOINT is non-zero if this LWP stopped with a data
|
|
watchpoint trap. */
|
|
int stopped_by_watchpoint;
|
|
|
|
/* On architectures where it is possible to know the data address of
|
|
a triggered watchpoint, STOPPED_DATA_ADDRESS is non-zero, and
|
|
contains such data address. Only valid if STOPPED_BY_WATCHPOINT
|
|
is true. */
|
|
CORE_ADDR stopped_data_address;
|
|
|
|
/* If this is non-zero, it is a breakpoint to be reinserted at our next
|
|
stop (SIGTRAP stops only). */
|
|
CORE_ADDR bp_reinsert;
|
|
|
|
/* If this flag is set, the last continue operation at the ptrace
|
|
level on this process was a single-step. */
|
|
int stepping;
|
|
|
|
/* Range to single step within. This is a copy of the step range
|
|
passed along the last resume request. See 'struct
|
|
thread_resume'. */
|
|
CORE_ADDR step_range_start; /* Inclusive */
|
|
CORE_ADDR step_range_end; /* Exclusive */
|
|
|
|
/* If this flag is set, we need to set the event request flags the
|
|
next time we see this LWP stop. */
|
|
int must_set_ptrace_flags;
|
|
|
|
/* If this is non-zero, it points to a chain of signals which need to
|
|
be delivered to this process. */
|
|
struct pending_signals *pending_signals;
|
|
|
|
/* A link used when resuming. It is initialized from the resume request,
|
|
and then processed and cleared in linux_resume_one_lwp. */
|
|
struct thread_resume *resume;
|
|
|
|
/* True if it is known that this lwp is presently collecting a fast
|
|
tracepoint (it is in the jump pad or in some code that will
|
|
return to the jump pad. Normally, we won't care about this, but
|
|
we will if a signal arrives to this lwp while it is
|
|
collecting. */
|
|
int collecting_fast_tracepoint;
|
|
|
|
/* If this is non-zero, it points to a chain of signals which need
|
|
to be reported to GDB. These were deferred because the thread
|
|
was doing a fast tracepoint collect when they arrived. */
|
|
struct pending_signals *pending_signals_to_report;
|
|
|
|
/* When collecting_fast_tracepoint is first found to be 1, we insert
|
|
a exit-jump-pad-quickly breakpoint. This is it. */
|
|
struct breakpoint *exit_jump_pad_bkpt;
|
|
|
|
/* True if the LWP was seen stop at an internal breakpoint and needs
|
|
stepping over later when it is resumed. */
|
|
int need_step_over;
|
|
|
|
#ifdef USE_THREAD_DB
|
|
int thread_known;
|
|
/* The thread handle, used for e.g. TLS access. Only valid if
|
|
THREAD_KNOWN is set. */
|
|
td_thrhandle_t th;
|
|
#endif
|
|
|
|
/* Arch-specific additions. */
|
|
struct arch_lwp_info *arch_private;
|
|
};
|
|
|
|
int linux_pid_exe_is_elf_64_file (int pid, unsigned int *machine);
|
|
|
|
/* Attach to PTID. Returns 0 on success, non-zero otherwise (an
|
|
errno). */
|
|
int linux_attach_lwp (ptid_t ptid);
|
|
|
|
/* Return the reason an attach failed, in string form. ERR is the
|
|
error returned by linux_attach_lwp (an errno). This string should
|
|
be copied into a buffer by the client if the string will not be
|
|
immediately used, or if it must persist. */
|
|
char *linux_attach_fail_reason_string (ptid_t ptid, int err);
|
|
|
|
struct lwp_info *find_lwp_pid (ptid_t ptid);
|
|
void linux_stop_lwp (struct lwp_info *lwp);
|
|
|
|
#ifdef HAVE_LINUX_REGSETS
|
|
void initialize_regsets_info (struct regsets_info *regsets_info);
|
|
#endif
|
|
|
|
void initialize_low_arch (void);
|
|
|
|
/* From thread-db.c */
|
|
int thread_db_init (int use_events);
|
|
void thread_db_detach (struct process_info *);
|
|
void thread_db_mourn (struct process_info *);
|
|
int thread_db_handle_monitor_command (char *);
|
|
int thread_db_get_tls_address (struct thread_info *thread, CORE_ADDR offset,
|
|
CORE_ADDR load_module, CORE_ADDR *address);
|
|
int thread_db_look_up_one_symbol (const char *name, CORE_ADDR *addrp);
|