From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by sourceware.org (Postfix) with ESMTP id D521F3858D35 for ; Wed, 29 Sep 2021 01:13:47 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org D521F3858D35 Received: from mail-vk1-f200.google.com (mail-vk1-f200.google.com [209.85.221.200]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-38-T3jEvNANP0KzeBDjcg5JxA-1; Tue, 28 Sep 2021 21:13:46 -0400 X-MC-Unique: T3jEvNANP0KzeBDjcg5JxA-1 Received: by mail-vk1-f200.google.com with SMTP id u84-20020a1f6057000000b002a087b75f0bso297162vkb.4 for ; Tue, 28 Sep 2021 18:13:46 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=Thih02Aym/IKSb17cgseOb4Q/oa+Q4USS96WHqtyCBY=; b=tSWFLrOtnw3cloyQC56WQEnSYD7f7Vdr1s9IvskmAWikxm2qdb7XExLdjo5I0dYKWE 1cz/+dB1riuVxOdiXvGmqyKrlmPNGZdFkeUyiEkmvfk0DDh+7ilpo7U19WmQkZb+GgWN Ihfo1YYM/84aQPU+H5CA7Eerl7NP+tyxKwUpLhTvoVSoGT83454Unq8iqC9KOkrciMYB g8gZNXOA1KLE1jwbhXIHqXR4pS7XuFShUVf55p1K/Hrb5a4UVjb1qQM578gkDcm18XFx GRcjGovrtyWM89dq9fDSUjG5KO4AdxD9e6yU9s277QC4jw15lHCb8Nc5025Hyca1xYGR B03Q== X-Gm-Message-State: AOAM530c07SZJh+sULodAKicZEjlJpd9WgxIEgYvoBSuLMJawk66JSZ1 X/jHLdQSTlSLNcF93m17SqHVc4si60zuYhaOWyxnHyomM/yZbQtqGLtoirUN2F25PHijOR3p/d+ h6v/Vew78VBgiTIPspGB46r3rcIWCu1y8E6oo X-Received: by 2002:a67:ad17:: with SMTP id t23mr396569vsl.35.1632878025511; Tue, 28 Sep 2021 18:13:45 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxqcXr15vWI7ALTBZnALSIkoeXmwo9eH4zCRld+sGZlHa5U1vzZ6PdDihOqWVrpF8gLHfN8y7bLa/vMjqRHwoE= X-Received: by 2002:a67:ad17:: with SMTP id t23mr396548vsl.35.1632878025192; Tue, 28 Sep 2021 18:13:45 -0700 (PDT) MIME-Version: 1.0 References: <20210812042406.75637-1-amerey@redhat.com> <20210812042406.75637-4-amerey@redhat.com> In-Reply-To: <20210812042406.75637-4-amerey@redhat.com> From: Aaron Merey Date: Tue, 28 Sep 2021 21:13:33 -0400 Message-ID: Subject: Re: [PATCH 3/3] PR gdb/27570: missing support for debuginfod in core_target::build_file_mappings To: gdb-patches@sourceware.org Cc: Simon Marchi , Tom Tromey X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="UTF-8" X-Spam-Status: No, score=-13.1 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 29 Sep 2021 01:13:50 -0000 Ping. Thanks, Aaron On Thu, Aug 12, 2021 at 12:25 AM Aaron Merey via Gdb-patches wrote: > > Add debuginfod support to core_target::build_file_mappings and > locate_exec_from_corefile_build_id to enable the downloading of > missing core file executables and shared libraries. > > Also add debuginfod support to solib_map_sections so that previously > downloaded shared libraries can be retrieved from the debuginfod > cache. > > When core file shared libraries are found locally, verify > that their build-ids match the corresponding build-id found in > the core file. If there is a mismatch, print a warning and attempt > to query debuginfod for the correct build of the shared library: > > warning: Build-id of /lib64/libc.so.6 does not match core file. > Downloading XY.Z MB executable for /lib64/libc.so.6 > --- > gdb/corelow.c | 33 +++++++++++++ > gdb/debuginfod-support.c | 46 +++++++++++++++++++ > gdb/debuginfod-support.h | 16 +++++++ > gdb/gcore.in | 3 ++ > gdb/solib.c | 35 ++++++++++++++ > .../gdb.debuginfod/fetch_src_and_symbols.exp | 25 +++++++++- > 6 files changed, 156 insertions(+), 2 deletions(-) > > diff --git a/gdb/corelow.c b/gdb/corelow.c > index 97eadceed84..2c9ea1044b7 100644 > --- a/gdb/corelow.c > +++ b/gdb/corelow.c > @@ -46,6 +46,8 @@ > #include "gdbsupport/filestuff.h" > #include "build-id.h" > #include "gdbsupport/pathstuff.h" > +#include "gdbsupport/scoped_fd.h" > +#include "debuginfod-support.h" > #include > #include > #include "gdbcmd.h" > @@ -229,6 +231,11 @@ core_target::build_file_mappings () > canonical) pathname will be provided. */ > gdb::unique_xmalloc_ptr expanded_fname > = exec_file_find (filename, NULL); > + > + if (expanded_fname == nullptr && build_id != nullptr) > + debuginfod_exec_query (build_id->data, build_id->size, > + filename, &expanded_fname); > + > if (expanded_fname == nullptr) > { > m_core_unavailable_mappings.emplace_back (start, end - start); > @@ -416,6 +423,32 @@ locate_exec_from_corefile_build_id (bfd *abfd, int from_tty) > symbol_file_add_main (bfd_get_filename (execbfd.get ()), > symfile_add_flag (from_tty ? SYMFILE_VERBOSE : 0)); > } > + else > + { > + gdb::unique_xmalloc_ptr execpath; > + scoped_fd fd = debuginfod_exec_query (build_id->data, build_id->size, > + abfd->filename, &execpath); > + > + if (fd.get () >= 0) > + { > + execbfd = gdb_bfd_open (execpath.get (), gnutarget); > + > + if (execbfd == nullptr) > + warning (_("File \"%s\" from debuginfod cannot be opened as bfd"), > + execpath.get ()); > + else if (!build_id_verify (execbfd.get (), build_id->size, > + build_id->data)) > + execbfd.reset (nullptr); > + else > + { > + /* Successful download */ > + exec_file_attach (execpath.get (), from_tty); > + symbol_file_add_main (execpath.get (), > + symfile_add_flag (from_tty ? > + SYMFILE_VERBOSE : 0)); > + } > + } > + } > } > > /* See gdbcore.h. */ > diff --git a/gdb/debuginfod-support.c b/gdb/debuginfod-support.c > index 2d626e335a0..04b39b57f6f 100644 > --- a/gdb/debuginfod-support.c > +++ b/gdb/debuginfod-support.c > @@ -41,6 +41,16 @@ debuginfod_debuginfo_query (const unsigned char *build_id, > { > return scoped_fd (-ENOSYS); > } > + > +scoped_fd > +debuginfod_exec_query (const unsigned char *build_id, > + int build_id_len, > + const char *filename, > + gdb::unique_xmalloc_ptr *destname) > +{ > + return scoped_fd (-ENOSYS); > +} > + > #else > #include > > @@ -194,4 +204,40 @@ debuginfod_debuginfo_query (const unsigned char *build_id, > > return fd; > } > + > +/* See debuginfod-support.h */ > + > +scoped_fd > +debuginfod_exec_query (const unsigned char *build_id, > + int build_id_len, > + const char *filename, > + gdb::unique_xmalloc_ptr *destname) > +{ > + const char *urls_env_var = getenv (DEBUGINFOD_URLS_ENV_VAR); > + if (urls_env_var == NULL || urls_env_var[0] == '\0') > + return scoped_fd (-ENOSYS); > + > + debuginfod_client *c = get_debuginfod_client (); > + > + if (c == nullptr) > + return scoped_fd (-ENOMEM); > + > + char *dname = nullptr; > + user_data data ("executable for", filename); > + > + debuginfod_set_user_data (c, &data); > + scoped_fd fd (debuginfod_find_executable (c, build_id, build_id_len, &dname)); > + debuginfod_set_user_data (c, nullptr); > + > + if (fd.get () < 0 && fd.get () != -ENOENT) > + printf_filtered (_("Download failed: %s. " \ > + "Continuing without executable for %ps.\n"), > + safe_strerror (-fd.get ()), > + styled_string (file_name_style.style (), filename)); > + > + if (fd.get () >= 0) > + destname->reset (dname); > + > + return fd; > +} > #endif > diff --git a/gdb/debuginfod-support.h b/gdb/debuginfod-support.h > index 5e5aab56e74..c29a07d2abe 100644 > --- a/gdb/debuginfod-support.h > +++ b/gdb/debuginfod-support.h > @@ -61,4 +61,20 @@ debuginfod_debuginfo_query (const unsigned char *build_id, > const char *filename, > gdb::unique_xmalloc_ptr *destname); > > +/* Query debuginfod servers for an executable file with BUILD_ID. > + BUILD_ID can be given as a binary blob or a null-terminated string. > + If given as a binary blob, BUILD_ID_LEN should be the number of bytes. > + If given as a null-terminated string, BUILD_ID_LEN should be 0. > + > + FILENAME should be the name or path associated with the executable. > + It is used for printing messages to the user. > + > + If the file is successfully retrieved, its path on the local machine > + is stored in DESTNAME. If GDB is not built with debuginfod, this > + function returns -ENOSYS. */ > + > +extern scoped_fd debuginfod_exec_query (const unsigned char *build_id, > + int build_id_len, > + const char *filename, > + gdb::unique_xmalloc_ptr *destname); > #endif /* DEBUGINFOD_SUPPORT_H */ > diff --git a/gdb/gcore.in b/gdb/gcore.in > index 24354a79e27..25b24c3cd3d 100644 > --- a/gdb/gcore.in > +++ b/gdb/gcore.in > @@ -89,6 +89,9 @@ if [ ! -f "$binary_path/@GDB_TRANSFORM_NAME@" ]; then > exit 1 > fi > > +# Prevent unnecessary debuginfod queries during core file generation. > +unset DEBUGINFOD_URLS > + > # Initialise return code. > rc=0 > > diff --git a/gdb/solib.c b/gdb/solib.c > index 8b92cf7db53..3a7bf59e64a 100644 > --- a/gdb/solib.c > +++ b/gdb/solib.c > @@ -49,6 +49,8 @@ > #include "filesystem.h" > #include "gdb_bfd.h" > #include "gdbsupport/filestuff.h" > +#include "gdbsupport/scoped_fd.h" > +#include "debuginfod-support.h" > #include "source.h" > #include "cli/cli-style.h" > > @@ -538,6 +540,39 @@ solib_map_sections (struct so_list *so) > > gdb::unique_xmalloc_ptr filename (tilde_expand (so->so_name)); > gdb_bfd_ref_ptr abfd (ops->bfd_open (filename.get ())); > + const char *build_id_hexstr = > + current_program_space->get_cbfd_soname_build_id (so->so_name); > + > + /* If we already have core file build-id information for this solib, > + verify it matches abfd's build-id. If there is a mismatch or > + the solib wasn't found, attempt to query debuginfod for > + the correct solib. */ > + if (build_id_hexstr != NULL) > + { > + bool mismatch = false; > + > + if (abfd != NULL && abfd->build_id != NULL) > + { > + std::string build_id = build_id_to_string (abfd->build_id); > + if (build_id != build_id_hexstr) > + { > + warning (_("Build-id of %ps does not match core file."), > + styled_string (file_name_style.style (), > + filename.get ())); > + mismatch = true; > + } > + } > + > + if (abfd == NULL || mismatch) > + { > + scoped_fd fd = debuginfod_exec_query ((const unsigned char*) > + build_id_hexstr, > + 0, so->so_name, &filename); > + > + if (fd.get () >= 0) > + abfd = ops->bfd_open (filename.get ()); > + } > + } > > if (abfd == NULL) > return 0; > diff --git a/gdb/testsuite/gdb.debuginfod/fetch_src_and_symbols.exp b/gdb/testsuite/gdb.debuginfod/fetch_src_and_symbols.exp > index 81d4791eb6d..79ec4e6f853 100644 > --- a/gdb/testsuite/gdb.debuginfod/fetch_src_and_symbols.exp > +++ b/gdb/testsuite/gdb.debuginfod/fetch_src_and_symbols.exp > @@ -58,6 +58,11 @@ if { [gdb_compile "$sourcetmp" "$binfile" executable {debug}] != "" } { > return -1 > } > > +if { [gdb_compile "$sourcetmp" "${binfile}2" executable {debug}] != "" } { > + fail "compile" > + return -1 > +} > + > # Write some assembly that just has a .gnu_debugaltlink section. > # Copied from testsuite/gdb.dwarf2/dwzbuildid.exp. > proc write_just_debugaltlink {filename dwzname buildid} { > @@ -109,8 +114,10 @@ proc write_dwarf_file {filename buildid {value 99}} { > } > } > > +set corefile "corefile" > + > proc no_url { } { > - global binfile outputdir debugdir > + global binfile corefile outputdir debugdir > > setenv DEBUGINFOD_URLS "" > > @@ -162,10 +169,20 @@ proc no_url { } { > gdb_test "file ${binfile}_alt.o" \ > ".*could not find '.gnu_debugaltlink'.*" \ > "file [file tail ${binfile}_alt.o]" > + > + # Generate a core file and test that gdb cannot find the executable > + clean_restart ${binfile}2 > + gdb_test "start" "Temporary breakpoint.*" > + gdb_test "generate-core-file $corefile" \ > + "Saved corefile $corefile" > + file rename -force ${binfile}2 $debugdir > + > + clean_restart > + gdb_test "core $corefile" ".*in ?? ().*" > } > > proc local_url { } { > - global binfile outputdir db debugdir > + global binfile corefile outputdir db debugdir > > # Find an unused port > set port 7999 > @@ -228,6 +245,10 @@ proc local_url { } { > gdb_test "file ${binfile}_alt.o" \ > ".*Reading symbols from ${binfile}_alt.o\.\.\.*" \ > "file [file tail ${binfile}_alt.o]" > + > + # gdb should now find the executable file > + clean_restart > + gdb_test "core $corefile" ".*return 0.*" > } > > set envlist \ > -- > 2.31.1 >