mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-25 06:20:06 +00:00
890b7a4b33
On s390/s390x backtrace(buffer, size) returns the series of called functions until "makecontext_ret" and additional entries (up to "size") with "makecontext_ret". GDB-backtrace is also warning: "Backtrace stopped: previous frame identical to this frame (corrupt stack?)" To reproduce this scenario you have to setup a new context with makecontext() and activate it with setcontext(). See e.g. cf() function in testcase stdlib/tst-makecontext.c. Or see bug in libgo "Bug 66303 - runtime.Caller() returns infinitely deep stack frames on s390x " (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66303). This patch omits the cfi_startproc/cfi_endproc directives in ENTRY/END macro of __makecontext_ret. Thus no frame information is generated in .eh_frame and backtrace stops after __makecontext_ret. There is also no .eh_frame info for _start or thread_start functions. ChangeLog: [BZ #18508] * stdlib/Makefile ($(objpfx)tst-makecontext3): Depend on $(libdl). * stdlib/tst-makecontext.c (cf): Test if _Unwind_Backtrace is not called infinitely times. (backtrace_helper): New function. (trace_arg): New struct. (st1): Enlarge stack size. * sysdeps/unix/sysv/linux/s390/s390-32/__makecontext_ret.S: (__makecontext_ret): Omit cfi_startproc and cfi_endproc. * sysdeps/unix/sysv/linux/s390/s390-64/__makecontext_ret.S: Likewise.
111 lines
2.8 KiB
C
111 lines
2.8 KiB
C
/* Copyright (C) 2006-2015 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library 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
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
#include <errno.h>
|
|
#include <stdlib.h>
|
|
#include <stdio.h>
|
|
#include <ucontext.h>
|
|
#include <assert.h>
|
|
#include <unwind.h>
|
|
#include <dlfcn.h>
|
|
#include <gnu/lib-names.h>
|
|
|
|
ucontext_t ucp;
|
|
char st1[16384];
|
|
__thread int thr;
|
|
|
|
int somevar = -76;
|
|
long othervar = -78L;
|
|
|
|
struct trace_arg
|
|
{
|
|
int cnt, size;
|
|
};
|
|
|
|
static _Unwind_Reason_Code
|
|
backtrace_helper (struct _Unwind_Context *ctx, void *a)
|
|
{
|
|
struct trace_arg *arg = a;
|
|
if (++arg->cnt == arg->size)
|
|
return _URC_END_OF_STACK;
|
|
return _URC_NO_REASON;
|
|
}
|
|
|
|
void
|
|
cf (int i)
|
|
{
|
|
struct trace_arg arg = { .size = 100, .cnt = -1 };
|
|
void *handle;
|
|
_Unwind_Reason_Code (*unwind_backtrace) (_Unwind_Trace_Fn, void *);
|
|
|
|
if (i != othervar || thr != 94)
|
|
{
|
|
printf ("i %d thr %d\n", i, thr);
|
|
exit (1);
|
|
}
|
|
|
|
/* Test if callback function of _Unwind_Backtrace is not called infinitely
|
|
times. See Bug 18508 or gcc bug "Bug 66303 - runtime.Caller() returns
|
|
infinitely deep stack frames on s390x.".
|
|
The go runtime calls backtrace_full() in
|
|
<gcc-src>/libbacktrace/backtrace.c, which uses _Unwind_Backtrace(). */
|
|
handle = dlopen (LIBGCC_S_SO, RTLD_LAZY);
|
|
if (handle != NULL)
|
|
{
|
|
unwind_backtrace = dlsym (handle, "_Unwind_Backtrace");
|
|
if (unwind_backtrace != NULL)
|
|
{
|
|
unwind_backtrace (backtrace_helper, &arg);
|
|
assert (arg.cnt != -1 && arg.cnt < 100);
|
|
}
|
|
dlclose (handle);
|
|
}
|
|
|
|
/* Since uc_link below has been set to NULL, setcontext is supposed to
|
|
terminate the process normally after this function returns. */
|
|
}
|
|
|
|
int
|
|
do_test (void)
|
|
{
|
|
if (getcontext (&ucp) != 0)
|
|
{
|
|
if (errno == ENOSYS)
|
|
{
|
|
puts ("context handling not supported");
|
|
return 0;
|
|
}
|
|
|
|
puts ("getcontext failed");
|
|
return 1;
|
|
}
|
|
thr = 94;
|
|
ucp.uc_link = NULL;
|
|
ucp.uc_stack.ss_sp = st1;
|
|
ucp.uc_stack.ss_size = sizeof st1;
|
|
makecontext (&ucp, (void (*) (void)) cf, 1, somevar - 2);
|
|
if (setcontext (&ucp) != 0)
|
|
{
|
|
puts ("setcontext failed");
|
|
return 1;
|
|
}
|
|
return 2;
|
|
}
|
|
|
|
#define TEST_FUNCTION do_test ()
|
|
#include "../test-skeleton.c"
|