From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 26565 invoked by alias); 27 Jul 2012 18:47:31 -0000 Received: (qmail 26551 invoked by uid 22791); 27 Jul 2012 18:47:29 -0000 X-SWARE-Spam-Status: No, hits=-5.5 required=5.0 tests=AWL,BAYES_00,FAKE_REPLY_C,KHOP_RCVD_UNTRUST,RCVD_IN_DNSWL_HI,RCVD_IN_HOSTKARMA_W,SPF_HELO_PASS,TW_DW,TW_VG,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Fri, 27 Jul 2012 18:47:15 +0000 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id q6RIklDB010407 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Fri, 27 Jul 2012 14:46:47 -0400 Received: from host2.jankratochvil.net (ovpn-116-33.ams2.redhat.com [10.36.116.33]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id q6RIkeNm032122 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO); Fri, 27 Jul 2012 14:46:42 -0400 Date: Fri, 27 Jul 2012 18:47:00 -0000 From: Jan Kratochvil To: Philippe Waroquiers , Pedro Alves Cc: Joel Brobecker , gdb-patches@sourceware.org, "Maciej W. Rozycki" Subject: Re: [patchv2] Write bpt at the ON_STACK bpt address Message-ID: <20120727184633.GA14182@host2.jankratochvil.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5012B1B6.1030003@redhat.com> <1343339398.2258.119.camel@soleil> User-Agent: Mutt/1.5.21 (2010-09-15) X-IsSubscribed: yes Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org X-SW-Source: 2012-07/txt/msg00706.txt.bz2 On Thu, 26 Jul 2012 23:49:58 +0200, Philippe Waroquiers wrote: > On Thu, 2012-07-26 at 23:23 +0200, Jan Kratochvil wrote: > > I still have to write a testcase for it using valgrind. > > IIUC, this implies to write a new 'gdbserver board file' (or something > like that) which will allow to access the Valgrind gdbsrv. There is valgrind board file (without gdbsrv). But I have found running the testsuite nightly with valgrind is not feasible, it is too costly resulting in various testsuite issues. I have added just regular testfile like there was already: gdb.base/valgrind-db-attach.exp > Note that this is covered by the Valgrind regression tests > (that is how the change of behaviour with 7.4.91 was detected). Somehow I was not notified soon enough in Fedora Rawhide, probably because Fedora valgrind maintenance is now affected by the dwz incompatibility. On Fri, 27 Jul 2012 17:20:22 +0200, Pedro Alves wrote: > FWIW, the patch looks good to me, and I don't think that > limiting to x86 is necessary: OK, thanks for review. I will yet wait for the Maciej's MIPS test, not sure what is the next 7.5 snapshot release. > IMO, this comment should also mention that in addition to being nice for > the user, this is actually _necessary_ for at least Valgrind v XXX.YYY. Done. Thanks, Jan gdb/ 2012-07-27 Jan Kratochvil * infcall.c (call_function_by_hand): Move BP_ADDR comment to AT_ENTRY_POINT. (call_function_by_hand) : Call write_memory with gdbarch_breakpoint_from_pc, if possible. (call_function_by_hand) : The BP_ADDR comment is moved here. gdb/doc/ 2012-07-27 Jan Kratochvil * gdbint.texinfo (Defining Other Architecture Features): Clarify *pcptr encoding for gdbarch_breakpoint_from_pc, bp_addr for gdbarch_push_dummy_call and bp_addr for gdbarch_push_dummy_code. gdb/testsuite/ 2012-07-27 Jan Kratochvil * gdb.base/valgrind-db-attach.exp: Do not run in remote mode. * gdb.base/valgrind-infcall.c: New file. * gdb.base/valgrind-infcall.exp: New file. diff --git a/gdb/doc/gdbint.texinfo b/gdb/doc/gdbint.texinfo index 5e00f1f..b66f80b 100644 --- a/gdb/doc/gdbint.texinfo +++ b/gdb/doc/gdbint.texinfo @@ -4540,8 +4540,10 @@ contents and size of a breakpoint instruction. It returns a pointer to a static string of bytes that encode a breakpoint instruction, stores the length of the string to @code{*@var{lenptr}}, and adjusts the program counter (if necessary) to point to the actual memory location where the -breakpoint should be inserted. May return @code{NULL} to indicate that -software breakpoints are not supported. +breakpoint should be inserted. The program counter (@code{*@var{pcptr}} +is inferior PC register encoded on the input and it is a plain address on the +output. Function may return @code{NULL} to indicate that software breakpoints +are not supported. Although it is common to use a trap instruction for a breakpoint, it's not required; for instance, the bit pattern could be an invalid @@ -4821,7 +4823,7 @@ instead of value. @anchor{gdbarch_push_dummy_call} Define this to push the dummy frame's call to the inferior function onto the stack. In addition to pushing @var{nargs}, the code should push @var{struct_addr} (when @var{struct_return} is non-zero), and -the return address (@var{bp_addr}). +the return address (@var{bp_addr}, in inferior PC register encoding). @var{function} is a pointer to a @code{struct value}; on architectures that use function descriptors, this contains the function descriptor value. @@ -4835,12 +4837,14 @@ instruction sequence (including space for a breakpoint) to which the called function should return. Set @var{bp_addr} to the address at which the breakpoint instruction -should be inserted, @var{real_pc} to the resume address when starting -the call sequence, and return the updated inner-most stack address. +should be inserted (in inferior PC register encoding), @var{real_pc} to the +resume address when starting the call sequence, and return the updated +inner-most stack address. By default, the stack is grown sufficient to hold a frame-aligned (@pxref{frame_align}) breakpoint, @var{bp_addr} is set to the address -reserved for that breakpoint, and @var{real_pc} set to @var{funaddr}. +reserved for that breakpoint (in inferior PC register encoding), and +@var{real_pc} set to @var{funaddr}. This method replaces @w{@code{gdbarch_call_dummy_location (@var{gdbarch})}}. diff --git a/gdb/infcall.c b/gdb/infcall.c index 51cd118..1b2c3d6 100644 --- a/gdb/infcall.c +++ b/gdb/infcall.c @@ -618,15 +618,38 @@ call_function_by_hand (struct value *function, int nargs, struct value **args) not just the breakpoint but also an extra word containing the size (?) of the structure being passed. */ - /* The actual breakpoint (at BP_ADDR) is inserted separatly so there - is no need to write that out. */ - switch (gdbarch_call_dummy_location (gdbarch)) { case ON_STACK: - sp = push_dummy_code (gdbarch, sp, funaddr, - args, nargs, target_values_type, - &real_pc, &bp_addr, get_current_regcache ()); + { + const gdb_byte *bp_bytes; + CORE_ADDR bp_addr_as_address; + int bp_size; + + /* Be careful BP_ADDR is in inferior PC encoding while + BP_ADDR_AS_ADDRESS is a plain memory address. */ + + sp = push_dummy_code (gdbarch, sp, funaddr, args, nargs, + target_values_type, &real_pc, &bp_addr, + get_current_regcache ()); + + /* Write a legitimate instruction at the point where the infcall + breakpoint is going to be inserted. While this instruction + is never going to be executed, a user investigating the + memory from GDB would see this instruction instead of random + uninitialized bytes. We chose the breakpoint instruction + as it may look as the most logical one to the user and also + valgrind 3.7.0 needs it for proper vgdb inferior calls. + + If software breakpoints are unsupported for this target we + leave the user visible memory content uninitialized. */ + + bp_addr_as_address = bp_addr; + bp_bytes = gdbarch_breakpoint_from_pc (gdbarch, &bp_addr_as_address, + &bp_size); + if (bp_bytes != NULL) + write_memory (bp_addr_as_address, bp_bytes, bp_size); + } break; case AT_ENTRY_POINT: { @@ -634,8 +657,12 @@ call_function_by_hand (struct value *function, int nargs, struct value **args) real_pc = funaddr; dummy_addr = entry_point_address (); + /* A call dummy always consists of just a single breakpoint, so - its address is the same as the address of the dummy. */ + its address is the same as the address of the dummy. + + The actual breakpoint is inserted separatly so there is no need to + write that out. */ bp_addr = dummy_addr; break; } diff --git a/gdb/testsuite/gdb.base/valgrind-db-attach.exp b/gdb/testsuite/gdb.base/valgrind-db-attach.exp index b14401f..313e4e0 100644 --- a/gdb/testsuite/gdb.base/valgrind-db-attach.exp +++ b/gdb/testsuite/gdb.base/valgrind-db-attach.exp @@ -13,6 +13,11 @@ # You should have received a copy of the GNU General Public License # along with this program. If not, see . +if [is_remote target] { + # The test always runs locally. + return 0 +} + set test valgrind-db-attach set srcfile $test.c set executable $test diff --git a/gdb/testsuite/gdb.base/valgrind-infcall.c b/gdb/testsuite/gdb.base/valgrind-infcall.c new file mode 100644 index 0000000..c119b7e --- /dev/null +++ b/gdb/testsuite/gdb.base/valgrind-infcall.c @@ -0,0 +1,40 @@ +/* This testcase is part of GDB, the GNU debugger. + + Copyright 2012 Free Software Foundation, Inc. + + 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 3 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, see . */ + +#include + +static volatile int infcall_var; + +static int +gdb_test_infcall (void) +{ + return ++infcall_var; +} + +int +main (void) +{ + void *p; + + gdb_test_infcall (); + p = malloc (1); + if (p == NULL) + return 1; + free (p); + free (p); /* double-free */ + return 0; +} diff --git a/gdb/testsuite/gdb.base/valgrind-infcall.exp b/gdb/testsuite/gdb.base/valgrind-infcall.exp new file mode 100644 index 0000000..ede26f4 --- /dev/null +++ b/gdb/testsuite/gdb.base/valgrind-infcall.exp @@ -0,0 +1,115 @@ +# Copyright 2012 Free Software Foundation, Inc. + +# 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 3 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, see . + +if [is_remote target] { + # The test always runs locally. + return 0 +} + +set test valgrind-infcall +set srcfile $test.c +set executable $test +set binfile ${objdir}/${subdir}/${executable} +if {[build_executable $test.exp $executable $srcfile {debug}] == -1} { + return -1 +} + +set test "spawn valgrind" +set cmd "valgrind --vgdb-error=0 $binfile" +set res [remote_spawn host $cmd]; +if { $res < 0 || $res == "" } { + verbose -log "Spawning $cmd failed." + unsupported $test + return -1 +} +pass $test +# Declare GDB now as running. +set gdb_spawn_id -1 + +# GDB started by vgdb stops already after the startup is executed, like with +# non-extended gdbserver. It is also not correct to run/attach the inferior. +set use_gdb_stub 1 + +set test "valgrind started" +# The trailing '.' differs for different memcheck versions. +gdb_test_multiple "" $test { + -re "Memcheck, a memory error detector\\.?\r\n" { + pass $test + } + -re "valgrind: failed to start tool 'memcheck' for platform '.*': No such file or directory" { + unsupported $test + return -1 + } + -re "valgrind: wrong ELF executable class" { + unsupported $test + return -1 + } + -re "command not found" { + # The spawn succeeded, but then valgrind was not found - e.g. if + # we spawned SSH to a remote system. + unsupported $test + return -1 + } + -re "valgrind: Bad option '--vgdb-error=0'" { + # valgrind is not >= 3.7.0. + unsupported $test + return -1 + } +} + +set test "vgdb prompt" +# The trailing '.' differs for different memcheck versions. +gdb_test_multiple "" $test { + -re " (target remote | \[^\r\n\]*/vgdb \[^\r\n\]*)\r\n" { + set vgdbcmd $expect_out(1,string) + pass $test + } +} + +# Do not kill valgrind. +unset gdb_spawn_id +set board [host_info name] +unset_board_info fileid + +clean_restart $executable + +gdb_test "$vgdbcmd" " in _start .*" "target remote for vgdb" + +gdb_test "monitor v.set gdb_output" "valgrind output will go to gdb.*" + +set continue_count 1 +while 1 { + set test "continue #$continue_count" + gdb_test_multiple "continue" "" { + -re "Invalid free\\(\\).*: main .*\r\n$gdb_prompt $" { + pass $test + break + } + -re "\r\n$gdb_prompt $" { + pass "$test (false warning)" + } + } + set continue_count [expr $continue_count + 1] +} + +set test "p gdb_test_infcall ()" +gdb_test_multiple $test $test { + -re "unhandled instruction bytes.*\r\n$gdb_prompt $" { + fail $test + } + -re "Continuing \\.\\.\\..*\r\n\\\$1 = 2\r\n$gdb_prompt $" { + pass $test + } +}