OpenE2K
/
binutils-gdb
12
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Fix TLS access for -static -pthread 

I have posted:
	TLS variables access for -static -lpthread executables
	https://sourceware.org/ml/libc-help/2014-03/msg00024.html
and the GDB patch below has been confirmed as OK for current glibcs.

Further work should be done for newer glibcs:
	Improve TLS variables glibc compatibility
	https://sourceware.org/bugzilla/show_bug.cgi?id=16954

Still the patch below implements the feature in a fully functional way backward
compatible with current glibcs, it depends on the following glibc source line:
	csu/libc-tls.c
	main_map->l_tls_modid = 1;

gdb/
2014-05-21  Jan Kratochvil  <jan.kratochvil@redhat.com>

	Fix TLS access for -static -pthread.
	* linux-thread-db.c (struct thread_db_info): Add td_thr_tlsbase_p.
	(try_thread_db_load_1): Initialize it.
	(thread_db_get_thread_local_address): Call it if LM is zero.
	* target.c (target_translate_tls_address): Remove LM_ADDR zero check.
	* target.h (struct target_ops) (to_get_thread_local_address): Add
	load_module_addr comment.

gdb/gdbserver/
2014-05-21  Jan Kratochvil  <jan.kratochvil@redhat.com>

	Fix TLS access for -static -pthread.
	* gdbserver/thread-db.c (struct thread_db): Add td_thr_tlsbase_p.
	(thread_db_get_tls_address): Call it if LOAD_MODULE is zero.
	(thread_db_load_search, try_thread_db_load_1): Initialize it.

gdb/testsuite/
2014-05-21  Jan Kratochvil  <jan.kratochvil@redhat.com>

	Fix TLS access for -static -pthread.
	* gdb.threads/staticthreads.c <HAVE_TLS> (tlsvar): New.
	<HAVE_TLS> (thread_function, main): Initialize it.
	* gdb.threads/staticthreads.exp: Try gdb_compile_pthreads for $have_tls.
	Add clean_restart.
	<$have_tls != "">: Check TLSVAR.

Message-ID: <20140410115204.GB16411@host2.jankratochvil.net>
This commit is contained in:
Jan Kratochvil 2014-05-21 16:25:53 +02:00
parent 0256a6ac4b
commit 5876f5032f
9 changed files with 131 additions and 32 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
gdb/ChangeLog
View File

@ -1,3 +1,13 @@
2014-05-21 Jan Kratochvil <jan.kratochvil@redhat.com>
Fix TLS access for -static -pthread.
* linux-thread-db.c (struct thread_db_info): Add td_thr_tlsbase_p.
(try_thread_db_load_1): Initialize it.
(thread_db_get_thread_local_address): Call it if LM is zero.
* target.c (target_translate_tls_address): Remove LM_ADDR zero check.
* target.h (struct target_ops) (to_get_thread_local_address): Add
load_module_addr comment.
2014-05-21 Pedro Alves <palves@redhat.com>
* dcache.c (dcache_read_memory_partial): If reading the cache line

7
gdb/gdbserver/ChangeLog
View File

@ -1,3 +1,10 @@
2014-05-21 Jan Kratochvil <jan.kratochvil@redhat.com>
Fix TLS access for -static -pthread.
* gdbserver/thread-db.c (struct thread_db): Add td_thr_tlsbase_p.
(thread_db_get_tls_address): Call it if LOAD_MODULE is zero.
(thread_db_load_search, try_thread_db_load_1): Initialize it.
2014-05-20 Pedro Alves <palves@redhat.com>
* linux-aarch64-low.c (aarch64_insert_point)

38
gdb/gdbserver/thread-db.c
View File

@ -88,6 +88,9 @@ struct thread_db
td_err_e (*td_thr_tls_get_addr_p) (const td_thrhandle_t *th,
psaddr_t map_address,
size_t offset, psaddr_t *address);
td_err_e (*td_thr_tlsbase_p) (const td_thrhandle_t *th,
unsigned long int modid,
psaddr_t *base);
const char ** (*td_symbol_list_p) (void);
};
@ -503,7 +506,10 @@ thread_db_get_tls_address (struct thread_info *thread, CORE_ADDR offset,
if (thread_db == NULL || !thread_db->all_symbols_looked_up)
return TD_ERR;
if (thread_db->td_thr_tls_get_addr_p == NULL)
/* If td_thr_tls_get_addr is missing rather do not expect td_thr_tlsbase
could work. */
if (thread_db->td_thr_tls_get_addr_p == NULL
|| (load_module == 0 && thread_db->td_thr_tlsbase_p == NULL))
return -1;
lwp = get_thread_lwp (thread);
@ -514,12 +520,28 @@ thread_db_get_tls_address (struct thread_info *thread, CORE_ADDR offset,
saved_inferior = current_inferior;
current_inferior = thread;
/* Note the cast through uintptr_t: this interface only works if
a target address fits in a psaddr_t, which is a host pointer.
So a 32-bit debugger can not access 64-bit TLS through this. */
err = thread_db->td_thr_tls_get_addr_p (&lwp->th,
(psaddr_t) (uintptr_t) load_module,
offset, &addr);
if (load_module != 0)
{
/* Note the cast through uintptr_t: this interface only works if
a target address fits in a psaddr_t, which is a host pointer.
So a 32-bit debugger can not access 64-bit TLS through this. */
err = thread_db->td_thr_tls_get_addr_p (&lwp->th,
(psaddr_t) (uintptr_t) load_module,
offset, &addr);
}
else
{
/* This code path handles the case of -static -pthread executables:
https://sourceware.org/ml/libc-help/2014-03/msg00024.html
For older GNU libc r_debug.r_map is NULL. For GNU libc after
PR libc/16831 due to GDB PR threads/16954 LOAD_MODULE is also NULL.
The constant number 1 depends on GNU __libc_setup_tls
initialization of l_tls_modid to 1. */
err = thread_db->td_thr_tlsbase_p (&lwp->th, 1, &addr);
addr = (char *) addr + offset;
}
current_inferior = saved_inferior;
if (err == TD_OK)
{
@ -571,6 +593,7 @@ thread_db_load_search (void)
tdb->td_ta_set_event_p = &td_ta_set_event;
tdb->td_ta_event_getmsg_p = &td_ta_event_getmsg;
tdb->td_thr_tls_get_addr_p = &td_thr_tls_get_addr;
tdb->td_thr_tlsbase_p = &td_thr_tlsbase;
return 1;
}
@ -639,6 +662,7 @@ try_thread_db_load_1 (void *handle)
CHK (0, tdb->td_ta_set_event_p = dlsym (handle, "td_ta_set_event"));
CHK (0, tdb->td_ta_event_getmsg_p = dlsym (handle, "td_ta_event_getmsg"));
CHK (0, tdb->td_thr_tls_get_addr_p = dlsym (handle, "td_thr_tls_get_addr"));
CHK (0, tdb->td_thr_tlsbase_p = dlsym (handle, "td_thr_tlsbase"));
#undef CHK

50
gdb/linux-thread-db.c
View File

@ -196,6 +196,9 @@ struct thread_db_info
td_err_e (*td_thr_tls_get_addr_p) (const td_thrhandle_t *th,
psaddr_t map_address,
size_t offset, psaddr_t *address);
td_err_e (*td_thr_tlsbase_p) (const td_thrhandle_t *th,
unsigned long int modid,
psaddr_t *base);
};
/* List of known processes using thread_db, and the required
@ -799,6 +802,7 @@ try_thread_db_load_1 (struct thread_db_info *info)
info->td_ta_event_getmsg_p = dlsym (info->handle, "td_ta_event_getmsg");
info->td_thr_event_enable_p = dlsym (info->handle, "td_thr_event_enable");
info->td_thr_tls_get_addr_p = dlsym (info->handle, "td_thr_tls_get_addr");
info->td_thr_tlsbase_p = dlsym (info->handle, "td_thr_tlsbase");
if (thread_db_find_new_threads_silently (inferior_ptid) != 0)
{
@ -1811,21 +1815,39 @@ thread_db_get_thread_local_address (struct target_ops *ops,
info = get_thread_db_info (ptid_get_pid (ptid));
/* glibc doesn't provide the needed interface. */
if (!info->td_thr_tls_get_addr_p)
throw_error (TLS_NO_LIBRARY_SUPPORT_ERROR,
_("No TLS library support"));
/* Caller should have verified that lm != 0. */
gdb_assert (lm != 0);
/* Finally, get the address of the variable. */
/* Note the cast through uintptr_t: this interface only works if
a target address fits in a psaddr_t, which is a host pointer.
So a 32-bit debugger can not access 64-bit TLS through this. */
err = info->td_thr_tls_get_addr_p (&thread_info->private->th,
(psaddr_t)(uintptr_t) lm,
offset, &address);
if (lm != 0)
{
/* glibc doesn't provide the needed interface. */
if (!info->td_thr_tls_get_addr_p)
throw_error (TLS_NO_LIBRARY_SUPPORT_ERROR,
_("No TLS library support"));
/* Note the cast through uintptr_t: this interface only works if
a target address fits in a psaddr_t, which is a host pointer.
So a 32-bit debugger can not access 64-bit TLS through this. */
err = info->td_thr_tls_get_addr_p (&thread_info->private->th,
(psaddr_t)(uintptr_t) lm,
offset, &address);
}
else
{
/* If glibc doesn't provide the needed interface throw an error
that LM is zero - normally cases it should not be. */
if (!info->td_thr_tlsbase_p)
throw_error (TLS_LOAD_MODULE_NOT_FOUND_ERROR,
_("TLS load module not found"));
/* This code path handles the case of -static -pthread executables:
https://sourceware.org/ml/libc-help/2014-03/msg00024.html
For older GNU libc r_debug.r_map is NULL. For GNU libc after
PR libc/16831 due to GDB PR threads/16954 LOAD_MODULE is also NULL.
The constant number 1 depends on GNU __libc_setup_tls
initialization of l_tls_modid to 1. */
err = info->td_thr_tlsbase_p (&thread_info->private->th,
1, &address);
address = (char *) address + offset;
}
#ifdef THREAD_DB_HAS_TD_NOTALLOC
/* The memory hasn't been allocated, yet. */

4
gdb/target.c
View File

@ -757,10 +757,6 @@ target_translate_tls_address (struct objfile *objfile, CORE_ADDR offset)
/* Fetch the load module address for this objfile. */
lm_addr = gdbarch_fetch_tls_load_module_address (target_gdbarch (),
objfile);
/* If it's 0, throw the appropriate exception. */
if (lm_addr == 0)
throw_error (TLS_LOAD_MODULE_NOT_FOUND_ERROR,
_("TLS load module not found"));
addr = target->to_get_thread_local_address (target, ptid,
lm_addr, offset);

3
gdb/target.h
View File

@ -605,7 +605,8 @@ struct target_ops
thread-local storage for the thread PTID and the shared library
or executable file given by OBJFILE. If that block of
thread-local storage hasn't been allocated yet, this function
may return an error. */
may return an error. LOAD_MODULE_ADDR may be zero for statically
linked multithreaded inferiors. */
CORE_ADDR (*to_get_thread_local_address) (struct target_ops *ops,
ptid_t ptid,
CORE_ADDR load_module_addr,

9
gdb/testsuite/ChangeLog
View File

@ -1,3 +1,12 @@
2014-05-21 Jan Kratochvil <jan.kratochvil@redhat.com>
Fix TLS access for -static -pthread.
* gdb.threads/staticthreads.c <HAVE_TLS> (tlsvar): New.
<HAVE_TLS> (thread_function, main): Initialize it.
* gdb.threads/staticthreads.exp: Try gdb_compile_pthreads for $have_tls.
Add clean_restart.
<$have_tls != "">: Check TLSVAR.
2014-05-21 Pedro Alves <palves@redhat.com>
* gdb.base/dcache-line-read-error.c: New.

12
gdb/testsuite/gdb.threads/staticthreads.c
View File

@ -28,10 +28,17 @@
sem_t semaphore;
#ifdef HAVE_TLS
__thread int tlsvar;
#endif
void *
thread_function (void *arg)
{
printf ("Thread executing\n");
#ifdef HAVE_TLS
tlsvar = 2;
#endif
printf ("Thread executing\n"); /* tlsvar-is-set */
while (sem_wait (&semaphore) != 0)
{
if (errno != EINTR)
@ -57,6 +64,9 @@ main (int argc, char **argv)
return -1;
}
#ifdef HAVE_TLS
tlsvar = 1;
#endif
/* Create a thread, wait for it to complete. */
{

30
gdb/testsuite/gdb.threads/staticthreads.exp
View File

@ -22,11 +22,16 @@
standard_testfile
set static_flag "-static"
if {[gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" \
executable \
[list debug "additional_flags=${static_flag}" \
]] != "" } {
return -1
foreach have_tls { "-DHAVE_TLS" "" } {
if {[gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" \
executable \
[list debug "additional_flags=${static_flag} ${have_tls}" \
]] == "" } {
break
}
if { $have_tls == "" } {
return -1
}
}
clean_restart ${binfile}
@ -89,3 +94,18 @@ gdb_test_multiple "quit" "$test" {
pass "$test"
}
}
clean_restart ${binfile}
if { "$have_tls" != "" } {
if ![runto_main] {
return -1
}
gdb_breakpoint [gdb_get_line_number "tlsvar-is-set"]
gdb_continue_to_breakpoint "tlsvar-is-set" ".* tlsvar-is-set .*"
gdb_test "p tlsvar" " = 2" "tlsvar in thread"
gdb_test "thread 1" ".*"
# Unwind from pthread_join.
gdb_test "up 10" " in main .*"
gdb_test "p tlsvar" " = 1" "tlsvar in main"
}