aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorStefan Liebler <stli@linux.vnet.ibm.com>2015-07-07 16:11:14 +0200
committerAndreas Krebbel <krebbel@linux.vnet.ibm.com>2015-07-07 16:11:14 +0200
commit890b7a4b33d482b5c768ab47d70758b80227e9bc (patch)
treed1c0d9f0005382a0b051f227f5a0ea9af89f89b3 /stdlib/Makefile
parentS390: Regenerate ULPs. (diff)
downloadglibc-890b7a4b33d482b5c768ab47d70758b80227e9bc.tar.gz
glibc-890b7a4b33d482b5c768ab47d70758b80227e9bc.tar.bz2
glibc-890b7a4b33d482b5c768ab47d70758b80227e9bc.zip
S390: Fix "backtrace() returns infinitely deep stack frames with makecontext()" [BZ #18508].
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.
Diffstat (limited to 'stdlib/Makefile')
-rw-r--r--stdlib/Makefile2
1 files changed, 2 insertions, 0 deletions
diff --git a/stdlib/Makefile b/stdlib/Makefile
index 3300dd2142..7fc5a807fa 100644
--- a/stdlib/Makefile
+++ b/stdlib/Makefile
@@ -164,3 +164,5 @@ $(objpfx)tst-setcontext3.out: tst-setcontext3.sh $(objpfx)tst-setcontext3
'$(run-program-env)' '$(test-program-prefix-after-env)' \
$(common-objpfx)stdlib/; \
$(evaluate-test)
+
+$(objpfx)tst-makecontext: $(libdl)