From: Markus Metzger <markus.t.metzger@intel.com>
To: gdb-patches@sourceware.org
Subject: [PATCH v5 05/15] gdb, gdbserver: extend RSP to support namespaces
Date: Thu, 2 Jun 2022 15:25:04 +0200 [thread overview]
Message-ID: <20220602132514.957983-6-markus.t.metzger@intel.com> (raw)
In-Reply-To: <20220602132514.957983-1-markus.t.metzger@intel.com>
Introduce a new qXfer:libraries-svr4:read annex key/value pair
lmid=<namespace identifier>
to be used together with start and prev to provide the namespace of start
and prev to gdbserver.
Unknown key/value pairs are ignored by gdbserver so no new supports check
is needed.
Introduce a new library-list-svr4 library attribute
lmid
to provide the namespace of a library entry to GDB.
This implementation uses the address of a namespace's r_debug object as
namespace identifier.
This should have incremented the minor version but since unknown XML
attributes are ignored, anyway, and since changing the version results in
a warning from GDB, the version is left at 1.0.
---
gdb/doc/gdb.texinfo | 16 +++++++++++--
gdb/features/library-list-svr4.dtd | 4 ++++
gdb/solib-svr4.c | 38 +++++++++++++++++++++++++++---
gdbserver/linux-low.cc | 26 +++++++++++++-------
4 files changed, 70 insertions(+), 14 deletions(-)
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 5f09f3a1433..e2f430feb7e 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -43334,6 +43334,12 @@ specified by the @samp{start} argument. If unset or zero then
the remote stub will expect that no @samp{struct link_map}
exists prior to the starting point.
+@item lmid=@var{lmid}
+A hexadecimal number specifying a namespace identifier. This is
+currently only used together with @samp{start} to provide the
+namespace identifier back to @value{GDBN} in the response.
+@value{GDBN} will only provide values that were previously reported to
+it. If unset, the response will include @samp{lmid="0x0"}.
@end table
Arguments that are not understood by the remote stub will be silently
@@ -45872,6 +45878,11 @@ memory address. It is a displacement of absolute memory address against
address the file was prelinked to during the library load.
@item
@code{l_ld}, which is memory address of the @code{PT_DYNAMIC} segment
+@item
+@code{lmid}, which is an identifier for a linker namespace, such as
+the memory address of the @code{r_debug} object that contains this
+namespace's load map or the namespace identifier returned by
+@code{dlinfo (3)}.
@end itemize
Additionally the single @code{main-lm} attribute specifies address of
@@ -45887,9 +45898,9 @@ looks like this:
@smallexample
<library-list-svr4 version="1.0" main-lm="0xe4f8f8">
<library name="/lib/ld-linux.so.2" lm="0xe4f51c" l_addr="0xe2d000"
- l_ld="0xe4eefc"/>
+ l_ld="0xe4eefc" lmid="0xfffe0"/>
<library name="/lib/libc.so.6" lm="0xe4fbe8" l_addr="0x154000"
- l_ld="0x152350"/>
+ l_ld="0x152350" lmid="0xfffe0"/>
</library-list-svr>
@end smallexample
@@ -45905,6 +45916,7 @@ The format of an SVR4 library list is described by this DTD:
<!ATTLIST library lm CDATA #REQUIRED>
<!ATTLIST library l_addr CDATA #REQUIRED>
<!ATTLIST library l_ld CDATA #REQUIRED>
+<!ATTLIST library lmid CDATA #IMPLIED>
@end smallexample
@node Memory Map Format
diff --git a/gdb/features/library-list-svr4.dtd b/gdb/features/library-list-svr4.dtd
index 7d62354c34c..e869ff1349e 100644
--- a/gdb/features/library-list-svr4.dtd
+++ b/gdb/features/library-list-svr4.dtd
@@ -14,3 +14,7 @@
<!ATTLIST library lm CDATA #REQUIRED>
<!ATTLIST library l_addr CDATA #REQUIRED>
<!ATTLIST library l_ld CDATA #REQUIRED>
+<!-- added lmid attribute to what should have become version 1.1 but
+ since this generates a warning in GDB and since unknown attributes
+ are ignored, anyway, leaving the version at 1.0. -->
+<!ATTLIST library lmid CDATA #IMPLIED>
diff --git a/gdb/solib-svr4.c b/gdb/solib-svr4.c
index 1f2abcf16ef..ca396acf24f 100644
--- a/gdb/solib-svr4.c
+++ b/gdb/solib-svr4.c
@@ -1068,8 +1068,37 @@ library_list_start_library (struct gdb_xml_parser *parser,
new_elem->so_name[sizeof (new_elem->so_name) - 1] = 0;
strcpy (new_elem->so_original_name, new_elem->so_name);
- *list->tailp = new_elem;
- list->tailp = &new_elem->next;
+ /* Older versions did not supply lmid. Put the element into the flat
+ list of the special namespace zero in that case. */
+ gdb_xml_value *at_lmid = xml_find_attribute (attributes, "lmid");
+ if (at_lmid == nullptr)
+ {
+ *list->tailp = new_elem;
+ list->tailp = &new_elem->next;
+ }
+ else
+ {
+ ULONGEST lmid = *(ULONGEST *) at_lmid->value.get ();
+
+ /* Ensure that the element is actually initialized. */
+ if (list->solib_lists.find (lmid) == list->solib_lists.end ())
+ list->solib_lists[lmid] = nullptr;
+
+ so_list **psolist = &list->solib_lists[lmid];
+ so_list **pnext = psolist;
+
+ /* Walk to the end of the list if we have one. */
+ so_list *solist = *psolist;
+ if (solist != nullptr)
+ {
+ for (; solist->next != nullptr; solist = solist->next)
+ /* Nothing. */;
+
+ pnext = &solist->next;
+ }
+
+ *pnext = new_elem;
+ }
}
/* Handle the start of a <library-list-svr4> element. */
@@ -1109,6 +1138,7 @@ static const struct gdb_xml_attribute svr4_library_attributes[] =
{ "lm", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL },
{ "l_addr", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL },
{ "l_ld", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL },
+ { "lmid", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL },
{ NULL, GDB_XML_AF_NONE, NULL, NULL }
};
@@ -1866,7 +1896,9 @@ solist_update_incremental (svr4_info *info, CORE_ADDR debug_base,
struct svr4_library_list library_list;
char annex[64];
- xsnprintf (annex, sizeof (annex), "start=%s;prev=%s",
+ /* Unknown key=value pairs are ignored by the gdbstub. */
+ xsnprintf (annex, sizeof (annex), "lmid=%s;start=%s;prev=%s",
+ phex_nz (debug_base, sizeof (debug_base)),
phex_nz (lm, sizeof (lm)),
phex_nz (prev_lm, sizeof (prev_lm)));
if (!svr4_current_sos_via_xfer_libraries (&library_list, annex))
diff --git a/gdbserver/linux-low.cc b/gdbserver/linux-low.cc
index 4b4d38b75bc..f54551f2eca 100644
--- a/gdbserver/linux-low.cc
+++ b/gdbserver/linux-low.cc
@@ -6481,8 +6481,8 @@ static const link_map_offsets lmo_64bit_offsets =
/* Get the loaded shared libraries from one namespace. */
static void
-read_link_map (std::string &document, CORE_ADDR lm_addr, CORE_ADDR lm_prev,
- int ptr_size, const link_map_offsets *lmo)
+read_link_map (std::string &document, CORE_ADDR lmid, CORE_ADDR lm_addr,
+ CORE_ADDR lm_prev, int ptr_size, const link_map_offsets *lmo)
{
CORE_ADDR l_name, l_addr, l_ld, l_next, l_prev;
@@ -6517,9 +6517,9 @@ read_link_map (std::string &document, CORE_ADDR lm_addr, CORE_ADDR lm_prev,
string_appendf (document, "<library name=\"");
xml_escape_text_append (&document, (char *) libname);
string_appendf (document, "\" lm=\"0x%s\" l_addr=\"0x%s\" "
- "l_ld=\"0x%s\"/>",
+ "l_ld=\"0x%s\" lmid=\"0x%s\"/>",
paddress (lm_addr), paddress (l_addr),
- paddress (l_ld));
+ paddress (l_ld), paddress (lmid));
}
lm_prev = lm_addr;
@@ -6539,7 +6539,7 @@ linux_process_target::qxfer_libraries_svr4 (const char *annex,
char filename[PATH_MAX];
int pid, is_elf64;
unsigned int machine;
- CORE_ADDR lm_addr = 0, lm_prev = 0;
+ CORE_ADDR lmid = 0, lm_addr = 0, lm_prev = 0;
if (writebuf != NULL)
return -2;
@@ -6573,7 +6573,9 @@ linux_process_target::qxfer_libraries_svr4 (const char *annex,
break;
name_len = sep - annex;
- if (name_len == 5 && startswith (annex, "start"))
+ if (name_len == 4 && startswith (annex, "lmid"))
+ addrp = &lmid;
+ else if (name_len == 5 && startswith (annex, "start"))
addrp = &lm_addr;
else if (name_len == 4 && startswith (annex, "prev"))
addrp = &lm_prev;
@@ -6592,19 +6594,25 @@ linux_process_target::qxfer_libraries_svr4 (const char *annex,
std::string document = "<library-list-svr4 version=\"1.0\"";
/* When the starting LM_ADDR is passed in the annex, only traverse that
- namespace.
+ namespace, which is assumed to be identified by LMID.
Otherwise, start with R_DEBUG and traverse all namespaces we find. */
if (lm_addr != 0)
{
document += ">";
- read_link_map (document, lm_addr, lm_prev, ptr_size, lmo);
+ read_link_map (document, lmid, lm_addr, lm_prev, ptr_size, lmo);
}
else
{
if (lm_prev != 0)
warning ("ignoring prev=0x%s without start", paddress (lm_prev));
+ /* We could interpret LMID as 'provide only the libraries for this
+ namespace' but GDB is currently only providing lmid, start, and
+ prev, or nothing. */
+ if (lmid != 0)
+ warning ("ignoring lmid=0x%s without start", paddress (lmid));
+
CORE_ADDR r_debug = priv->r_debug;
if (r_debug == 0)
r_debug = priv->r_debug = get_r_debug (pid, is_elf64);
@@ -6670,7 +6678,7 @@ linux_process_target::qxfer_libraries_svr4 (const char *annex,
}
}
- read_link_map (document, lm_addr, lm_prev, ptr_size, lmo);
+ read_link_map (document, r_debug, lm_addr, lm_prev, ptr_size, lmo);
if (r_version < 2)
break;
--
2.35.3
Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928
next prev parent reply other threads:[~2022-06-02 14:29 UTC|newest]
Thread overview: 52+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-06-02 13:24 [PATCH v5 00/15] basic linker namespace support Markus Metzger
2022-06-02 13:25 ` [PATCH v5 01/15] gdb, testsuite: extend gdb_test_multiple checks Markus Metzger
2022-06-13 1:28 ` Kevin Buettner
2022-06-02 13:25 ` [PATCH v5 02/15] gdb, solib-svr4: remove locate_base() Markus Metzger
2022-06-02 23:04 ` Kevin Buettner
2022-06-02 13:25 ` [PATCH v5 03/15] gdb, gdbserver: support dlmopen() Markus Metzger
2022-06-19 4:02 ` Kevin Buettner
2022-06-27 12:55 ` Metzger, Markus T
2022-06-30 22:35 ` Kevin Buettner
2022-06-02 13:25 ` [PATCH v5 04/15] gdbserver: move main_lm handling into caller Markus Metzger
2022-06-19 4:22 ` Kevin Buettner
2022-06-02 13:25 ` Markus Metzger [this message]
2022-06-02 16:09 ` [PATCH v5 05/15] gdb, gdbserver: extend RSP to support namespaces Eli Zaretskii
2022-06-19 4:32 ` Kevin Buettner
2022-06-02 13:25 ` [PATCH v5 06/15] gdb, compile: unlink objfile stored in module Markus Metzger
2022-06-23 17:20 ` Kevin Buettner
2022-06-02 13:25 ` [PATCH v5 07/15] gdb, python: use gdbarch_iterate_over_objfiles_in_search_order Markus Metzger
2022-06-24 17:18 ` Kevin Buettner
2022-06-02 13:25 ` [PATCH v5 08/15] gdb, ada: collect standard exceptions in all objfiles Markus Metzger
2022-06-24 17:26 ` Kevin Buettner
2022-07-18 16:49 ` Tom Tromey
2022-07-18 5:35 ` Metzger, Markus T
2022-09-14 8:19 ` Metzger, Markus T
2022-09-14 8:37 ` Joel Brobecker
2022-09-14 8:45 ` Metzger, Markus T
2022-06-02 13:25 ` [PATCH v5 09/15] gdb, ada: update ada_lookup_simple_minsym Markus Metzger
2022-06-24 23:42 ` Kevin Buettner
2022-07-18 17:02 ` Tom Tromey
2022-07-19 7:14 ` Metzger, Markus T
2022-09-14 8:19 ` Metzger, Markus T
2022-09-21 16:11 ` Tom Tromey
2022-06-02 13:25 ` [PATCH v5 10/15] gdb, ada: update ada_add_all_symbols Markus Metzger
2022-06-24 23:53 ` Kevin Buettner
2022-07-18 5:36 ` Metzger, Markus T
2022-07-18 16:56 ` Tom Tromey
2022-07-19 7:13 ` Metzger, Markus T
2022-07-19 12:23 ` Tom Tromey
2022-07-19 13:49 ` Metzger, Markus T
2022-06-02 13:25 ` [PATCH v5 11/15] gdb, cp: update add_symbol_overload_list_qualified Markus Metzger
2022-06-24 23:59 ` Kevin Buettner
2022-06-02 13:25 ` [PATCH v5 12/15] gdb, hppa: remove unused hppa_lookup_stub_minimal_symbol Markus Metzger
2022-06-25 0:01 ` Kevin Buettner
2022-06-02 13:25 ` [PATCH v5 13/15] gdb, symtab: inline find_quick_global_symbol_language Markus Metzger
2022-06-25 0:16 ` Kevin Buettner
2022-06-02 13:25 ` [PATCH v5 14/15] gdb: update gnu ifunc resolve Markus Metzger
2022-06-25 0:34 ` Kevin Buettner
2022-06-02 13:25 ` [PATCH v5 15/15] gdb, solib-svr4: support namespaces in DSO iteration Markus Metzger
2022-06-25 0:42 ` Kevin Buettner
2022-07-15 10:30 ` [PATCH v5 00/15] basic linker namespace support Metzger, Markus T
2022-07-16 0:04 ` Kevin Buettner
2022-07-18 5:33 ` Metzger, Markus T
2022-10-05 11:16 ` Metzger, Markus T
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