That's a false positive. sgen conservatively scans the stack and this does trip valgrind.
On Fri, Nov 21, 2014 at 10:29 AM, terender <[email protected]> wrote: > There is a memory problem with mono-sgen on linux. I'm using some pinned > byte[] buffers in my project, and there's a randomly crash with signal > SIGSEGV, it could happen anywhere at anytime. > > I guess there's some write oprations out of bound in memory, so I use > valgrind to check the program. > > Then I found that a while after the program start within some alloc > oprations, valgrind report a problem in sgen that is: > > ==6504== Thread 1: > ==6504== Conditional jump or move depends on uninitialised value(s) > ==6504== at 0x5C4D46: conservatively_pin_objects_from (sgen-gc.c:1200) > ==6504== by 0x5C5322: scan_thread_data (sgen-gc.c:3778) > ==6504== by 0x5CA7BA: collect_nursery (sgen-gc.c:2298) > ==6504== by 0x5CB877: sgen_perform_collection (sgen-gc.c:3196) > ==6504== by 0x5E8CCF: mono_gc_alloc_obj_nolock (sgen-alloc.c:315) > ==6504== by 0x5E90E3: mono_gc_alloc_obj (sgen-alloc.c:491) > ==6504== by 0x40C09E2: ??? > ==6504== by 0x4198331: ??? > ==6504== by 0x40BBF42: ??? > ==6504== by 0x41DE33: mono_jit_runtime_invoke (mini.c:6738) > ==6504== by 0x5A252A: mono_runtime_invoke (object.c:2831) > ==6504== by 0x5A5DCF: mono_runtime_exec_main (object.c:4096) > ==6504== Uninitialised value was created by a stack allocation > ==6504== at 0x57D2E0: start_wrapper (threads.c:701) > > > Any read or write oprations right after that would trigger an Invalid > write/read error in valgrind and then process got killed. > > Is that a bug in sgen collect_nursery with pinned objects in nursery heap? > > I have checked on both mono 3.2.3 and 3.10.0, and I'm using tarball to > compile them myself. > The enviroment is CentOS 6.6 Kernal 2.6.32-358.6.2.el6.x86_64, GCC version > 4.4.7 > > I could upload the whole log of valgrind for both mono 3.2.3 and 3.10.0 if > needed. > > > Btw: the problem does not happen if I use boehm > > > > > -- > View this message in context: > http://mono.1490590.n4.nabble.com/Problem-with-sgen-tp4664753.html > Sent from the Mono - General mailing list archive at Nabble.com. > _______________________________________________ > Mono-list maillist - [email protected] > http://lists.ximian.com/mailman/listinfo/mono-list >
_______________________________________________ Mono-list maillist - [email protected] http://lists.ximian.com/mailman/listinfo/mono-list
