Bug 85076

Summary: ARM JIT causes segmentation fault on javascript-heavy pages
Product: WebKit Reporter: Daniel Drake <dsd>
Component: JavaScriptCoreAssignee: Nobody <webkit-unassigned>
Status: UNCONFIRMED    
Severity: Normal CC: 13007199500, compnerd, hojong.han, loki, pbrobinson, rdieter, simon, zherczeg
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: Other   
OS: Linux   
Attachments:
Description Flags
Attempted gdb diagnostics none

Daniel Drake
Reported 2012-04-27 10:08:19 PDT
Created attachment 139221 [details] Attempted gdb diagnostics OLPC is moving from xulrunner to webkit. This is working great on our x86 laptops, but not on our latest ("XO-1.75") ARMv7 laptop. We are running Fedora 17 with webkitgtk-1.8.1 (GTK3). On the ARM platform, loading a javascript-heavy webpage causes a crash. Reproduced in Epiphany and OLPC's own "Browse activity" for the Sugar desktop. Reproduces very easily - loading gmail or Google Docs will cause an instant crash most of the time. Unfortunately gdb is not helpful with the crash. With all relevant debuginfo packages installed: (gdb) bt #0 0x00000024 in ?? () #1 0x49f0eaf4 in ?? () #2 0x49f0eaf4 in ?? () The crash can't be reproduced on identical configuration on x86. WebKit was built with these options: WebKit was configured with the following options: Build configuration: Enable debugging (slow) : no Compile with debug symbols (slow) : no Enable debug features (slow) : no Enable GCC build optimization : yes Code coverage support : no Unicode backend : icu Font backend : freetype Optimized memory allocator : yes Accelerated Compositing : no Features: WebGL : yes Blob support : yes DOM mutation observer support : no DeviceOrientation support : no Directory upload : no Fast Mobile Scrolling : no JIT compilation : yes Filters support : yes Geolocation support : yes JavaScript debugger/profiler support : yes Gamepad support : no MathML support : yes Media source : no Media statistics : no MHTML support : no HTML5 channel messaging support : yes HTML5 meter element support : yes HTML5 microdata support : no Page Visibility API support : no HTML5 progress element support : yes HTML5 client-side session and persistent storage support : yes SQL client-side database storage support : yes HTML5 datagrid support : no HTML5 data transfer items support : no HTML5 FileSystem API support : no Quota API support : no HTML5 sandboxed iframe support : yes HTML5 video element support : yes HTML5 track element support : no Fullscreen API support : yes Media stream support : no Icon database support : yes Image resizer support : no Link prefetch support : no Opcode stats : no Shadow DOM support : yes SharedWorkers support : yes Color input support : no Speech input support : no SVG support : yes SVG fonts support : yes Web Audio support : no Web Sockets support : yes Web Timing support : no Web Workers support : yes XSLT support : yes Spellcheck support : yes Animation API : no RequestAnimationFrame support : yes Touch Icon Loading support : no Register Protocol Handler support : no WebKit2 support : no WebKit2 plugin process : no GTK+ configuration: GTK+ version : 3.0 GDK target : x11 Hildon UI extensions : no GStreamer version : 0.10 Introspection support : yes Generate documentation : no
Attachments
Attempted gdb diagnostics (5.27 KB, text/plain)
2012-04-27 10:08 PDT, Daniel Drake 		no flags
Details
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Daniel Drake
Comment 1 2012-04-30 08:55:03 PDT
Recompiling webkit with --disable-jit "solves" the issue. So it seems to be a bug in the ARM JIT. This would also explain why gdb can't tell which library this code is coming from.
Zoltan Herczeg
Comment 2 2012-04-30 12:04:33 PDT
This is very interesting from your log: pc 0x24 0x24 I see you disassembled the content of the link register. Could you disasseble a bit back? For example: x/i $lr-32, $lr+4 Anyway a reduced test case would also be helpful.
Daniel Drake
Comment 3 2012-04-30 12:14:38 PDT
Thanks for looking at this, Zoltan. (gdb) x/i $lr-32, $lr+4 0x49f0eaf8: mov r2, lr (gdb) x/12i $lr-32 0x49f0ead4: blx r8 0x49f0ead8: b 0x49f0d0d0 0x49f0eadc: mov r0, sp 0x49f0eae0: str r4, [sp, #3118288] ; 0x60 0x49f0eae4: ldr r3, [pc, #33757136] ; 0x49f0ed3c 0x49f0eae8: str r4, [r3] 0x49f0eaec: ldr r8, [pc, #33757136] ; 0x49f0ed40 0x49f0eaf0: blx r8 0x49f0eaf4: b 0x49f0b164 0x49f0eaf8: mov r2, lr 0x49f0eafc: str r2, [r4, #-3118288] 0x49f0eb00: ldr r8, [pc, #33757136] ; 0x49f0ed48 Finding a less complex webpage that reliably reproduces this is difficult. On other sites we're finding that it crashes, but not always. I'll keep an eye open though.
Daniel Drake
Comment 4 2012-04-30 12:27:02 PDT
Core dump of the above crash: http://dev.laptop.org/~dsd/20120430/webkit85076.core.bz2
Zoltan Herczeg
Comment 5 2012-04-30 13:47:49 PDT
> 0x49f0eaec: ldr r8, [pc, #33757136] ; 0x49f0ed40 > 0x49f0eaf0: blx r8 This should be the culprit. Could you check address 0x49f0ed40? (= $pc + #33757136) I suspect it will be 0x24
Daniel Drake
Comment 6 2012-04-30 14:00:58 PDT
(gdb) x 0x49f0ed40 0x49f0ed40: 0x41d5d15c Is that what you're looking for?
Daniel Drake
Comment 7 2012-04-30 14:03:07 PDT
Guessing here, but maybe this is also interesting: (gdb) x/10i 0x41d5d15c 0x41d5d15c <_ZN3JSC4Heap9markRootsEb+1536>: eor r9, r9, r9, lsl #12 0x41d5d160 <_ZN3JSC4Heap9markRootsEb+1540>: eor r9, r9, r9, lsr #7 0x41d5d164 <_ZN3JSC4Heap9markRootsEb+1544>: eor r9, r9, r9, lsl #2 0x41d5d168 <_ZN3JSC4Heap9markRootsEb+1548>: eor r9, r9, r9, lsr #20 0x41d5d16c <_ZN3JSC4Heap9markRootsEb+1552>: orr r9, r9, #1 0x41d5d170 <_ZN3JSC4Heap9markRootsEb+1556>: b 0x41d5d17c <_ZN3JSC4Heap9markRootsEb+1568> 0x41d5d174 <_ZN3JSC4Heap9markRootsEb+1560>: cmp r1, #0 0x41d5d178 <_ZN3JSC4Heap9markRootsEb+1564>: beq 0x41d5d1dc <_ZN3JSC4Heap9markRootsEb+1664> 0x41d5d17c <_ZN3JSC4Heap9markRootsEb+1568>: cmp r2, #0 0x41d5d180 <_ZN3JSC4Heap9markRootsEb+1572>: moveq r2, r9
Zoltan Herczeg
Comment 8 2012-04-30 14:20:41 PDT
> Is that what you're looking for? Yeah, if the constants are not changed. I mean pc+#33757136 can be different if you rerun the program. 0x49f0eaec: ldr r8, [pc, #33757136] ; 0x49f0ed40 Anyway, this is clearly a rubish not a valid function: 0x41d5d15c <_ZN3JSC4Heap9markRootsEb+1536>: eor r9, r9, r9, lsl #12 0x41d5d160 <_ZN3JSC4Heap9markRootsEb+1540>: eor r9, r9, r9, lsr #7 This is clearly a fallbackpath: 0x49f0eadc: mov r0, sp 0x49f0eae0: str r4, [sp, #3118288] ; 0x60 0x49f0eae4: ldr r3, [pc, #33757136] ; 0x49f0ed3c 0x49f0eae8: str r4, [r3] 0x49f0eaec: ldr r8, [pc, #33757136] ; 0x49f0ed40 0x49f0eaf0: blx r8 0x49f0eaf4: b 0x49f0b164 Question is, what pc+#33757136 should contain in the right case. Btw is webkitgtk-1.8.1 contains the latest trunk? I mean this might already been fixed... Ah an idea! Instead of x/i write it as x/x and the x/x number again. I mean lets pc+#33757136 be 0x49f0ed40. Type x/x 0x49f0ed40 it will write you a number. x/x that number again, and tell me what it is.
Daniel Drake
Comment 9 2012-04-30 14:27:04 PDT
I'm working from the same core dump so nothing should change. Yes, I agree it looks strange that it is jumping right into the middle of a function. (gdb) x/x 0x49f0ed40 0x49f0ed40: 0x41d5d15c (gdb) x/x 0x41d5d15c 0x41d5d15c <_ZN3JSC4Heap9markRootsEb+1536>: 0xe0299609 I'm not in a good position to test webkit trunk at the moment. I will try to build it on Wednesday. In the mean time please let me know if you have any other ideas.
Zoltan Herczeg
Comment 10 2012-04-30 15:29:45 PDT
> Yes, I agree it looks strange that it is jumping right into the middle of a function. Unlikely. I think this is simply the closest symbol gdb can find. 1536 is just too big. Could you check the other constants? These are fallback functions, following each other one-by-one: 0x49f0ead4: blx r8 0x49f0ead8: b 0x49f0d0d0 --- fallback 0x49f0eadc: mov r0, sp 0x49f0eae0: str r4, [sp, #3118288] ; 0x60 0x49f0eae4: ldr r3, [pc, #33757136] ; 0x49f0ed3c 0x49f0eae8: str r4, [r3] 0x49f0eaec: ldr r8, [pc, #33757136] ; 0x49f0ed40 0x49f0eaf0: blx r8 0x49f0eaf4: b 0x49f0b164 --- fallback 0x49f0eaf8: mov r2, lr 0x49f0eafc: str r2, [r4, #-3118288] 0x49f0eb00: ldr r8, [pc, #33757136] ; 0x49f0ed48 They all have such sequence: 0x49f0eaec: ldr r8, [pc, #33757136] ; 0x49f0ed40 0x49f0eaf0: blx r8 Could you check whether their constant points to a valid function? So this is the only exception or something totally messed up in the constant pool.
Daniel Drake
Comment 11 2012-04-30 16:49:01 PDT
Sorry, think I've wasted a bit of your time. It looks like I had installed a different webkit build since the crash, and this was affecting the gdb output. Putting the right build back (the one from which the core was captured), I get different output. So, stepping back a bit. lr is still 0x49f0eaf4 The preceding instructions: 0x49f0ead0: ldr r8, [pc, #26091512] ; 0x49f0ed34 0x49f0ead4: blx r8 0x49f0ead8: b 0x49f0d0d0 0x49f0eadc: mov r0, sp 0x49f0eae0: str r4, [sp, #3118288] ; 0x60 0x49f0eae4: ldr r3, [pc, #26091512] ; 0x49f0ed3c 0x49f0eae8: str r4, [r3] 0x49f0eaec: ldr r8, [pc, #26091512] ; 0x49f0ed40 0x49f0eaf0: blx r8 0x49f0eaf4: b 0x49f0b164 So, value of 0x49f0ed40 (gdb) x/x 0x49f0ed40 0x49f0ed40: 0x41d5d15c Nothing new until now. But lets look at that code with the right library in place: 0x41d5d15c <cti_op_get_by_id_proto_fail+8>: ldr lr, [sp, #3118288] ; 0x40 0x41d5d160 <cti_op_get_by_id_proto_fail+12>: mov pc, lr 0x41d5d164 <cti_op_get_by_id_array_fail>: str lr, [sp, #3118288] ; 0x40 0x41d5d168 <cti_op_get_by_id_array_fail+4>: bl 0x41cae2e8 This looks suspicious. Does it tell you anything? Just to compare, the previous fallback condition is: 0x49f0ead0: ldr r8, [pc, #26091512] ; 0x49f0ed34 0x49f0ead4: blx r8 (gdb) x/x 0x49f0ed34 0x49f0ed34: 0x41d5d1ac (gdb) x/4i 0x41d5d1ac 0x41d5d1ac <cti_op_del_by_id+8>: ldr lr, [sp, #3118288] ; 0x40 0x41d5d1b0 <cti_op_del_by_id+12>: mov pc, lr 0x41d5d1b4 <cti_op_mul>: str lr, [sp, #3118288] ; 0x40 0x41d5d1b8 <cti_op_mul+4>: bl 0x41caf998
Zoltan Herczeg
Comment 12 2012-05-01 01:10:45 PDT
No problem. This is entirely different now. > Nothing new until now. But lets look at that code with the right library in place: > > 0x41d5d15c <cti_op_get_by_id_proto_fail+8>: > ldr lr, [sp, #3118288] ; 0x40 > 0x41d5d160 <cti_op_get_by_id_proto_fail+12>: mov pc, lr > 0x41d5d164 <cti_op_get_by_id_array_fail>: > str lr, [sp, #3118288] ; 0x40 > 0x41d5d168 <cti_op_get_by_id_array_fail+4>: bl 0x41cae2e8 > > This looks suspicious. Does it tell you anything? Yeah it is really suspicious. The sequence should look like this: str lr, [sp, ...] bl ... ldr lr, [sp, ...] mov pc, lr Generated by: #define DEFINE_STUB_FUNCTION(rtype, op) \ extern "C" { \ rtype JITStubThunked_##op(STUB_ARGS_DECLARATION); \ }; \ asm ( \ ".globl " SYMBOL_STRING(cti_##op) "\n" \ SYMBOL_STRING(cti_##op) ":" "\n" \ "str lr, [sp, #" STRINGIZE_VALUE_OF(THUNK_RETURN_ADDRESS_OFFSET) "]" "\n" \ "bl " SYMBOL_STRING(JITStubThunked_##op) "\n" \ "ldr lr, [sp, #" STRINGIZE_VALUE_OF(THUNK_RETURN_ADDRESS_OFFSET) "]" "\n" \ "mov pc, lr" "\n" \ ); \ rtype JITStubThunked_##op(STUB_ARGS_DECLARATION) and #define THUNK_RETURN_ADDRESS_OFFSET 0x38 (so #3118288 is somewhat way too big for me) In other words, something added 8 to the offset of these so called "stubs". Same as the second function. Question is why... Perhaps a very simple web page with simple JS with calling fallbacks like could also reveal this error: <script> var a = {}; a["a"]=5; </script>
Daniel Drake
Comment 13 2012-05-01 15:33:23 PDT
Working from home today, with a different laptop. So not using the same trace as earlier. Lets start over with a new crash. (gdb) bt #0 0x000013e4 in ?? () #1 0x499fe5dc in ?? () #2 0x499fe5dc in ?? () Backtrace stopped: previous frame identical to this frame (corrupt stack?) (gdb) info registers r0 0x4996e240 1234625088 r1 0xfffffffb 4294967291 r2 0x4996e240 1234625088 r3 0xfffffffb 4294967291 r4 0x47626688 1197631112 r5 0x1d2 466 r6 0x47626588 1197630856 r7 0x5357c57c 1398261116 r8 0x41d9f3e4 1104802788 r9 0x47626570 1197630832 r10 0x45a67400 1168536576 r11 0x41f55058 1106595928 r12 0x4c1d0ab0 1276971696 sp 0xbe8aed78 0xbe8aed78 lr 0x499fe5dc 1235215836 pc 0x13e4 0x13e4 cpsr 0x600f0010 1611595792 Check around the LR area again: (gdb) x/12i $lr-32 0x499fe5bc: mov r0, sp 0x499fe5c0: str r4, [sp, #3118288] ; 0x60 0x499fe5c4: mov r8, #408 ; 0x198 0x499fe5c8: str r8, [r4, #-3118288] ; 0x2c 0x499fe5cc: ldr r3, [pc, #12638680] ; 0x499fea40 0x499fe5d0: str r4, [r3] 0x499fe5d4: ldr r8, [pc, #12638680] ; 0x499fea44 0x499fe5d8: blx r8 0x499fe5dc: str r0, [r4, #3118288] ; 0x70 0x499fe5e0: str r1, [r4, #3118288] ; 0x74 0x499fe5e4: b 0x499fc264 0x499fe5e8: b 0x499fe618 Looking carefully at this instruction: 0x499fe5d4: ldr r8, [pc, #12638680] ; 0x499fea44 Lets try this calculation by hand. PC is always 8 bytes ahead of the current instruction, so pc=0x499fe5d4 + 8. Then we add 12638680, and we read from that memory location. 0x499fe5d4 + 8 + 12638680 = 0x4a60bfb4 so: (gdb) x/x 0x4a60bfb4 0x4a60bfb4: 0x00000000 Hmm, unlikely. But gdb's annotation said 0x499fea44. After asking around a bit I've been told that the number inside the square brackets is not to be taken literally. It includes flags and other things. However, the address in the annotation can be trusted. So, lets check the memory at that address. (gdb) x/x 0x499fea44 0x499fea44: 0x41d9f3e4 (gdb) x/4i 0x41d9f3e4 0x41d9f3e4 <cti_op_resolve_global>: str lr, [sp, #3118288] ; 0x40 0x41d9f3e8 <cti_op_resolve_global+4>: bl 0x41cf4aac 0x41d9f3ec <cti_op_resolve_global+8>: ldr lr, [sp, #3118288] ; 0x40 0x41d9f3f0 <cti_op_resolve_global+12>: mov pc, lr And lets also recall that r8 was programmed with this address before we branched. Checking back to the original register dump, r8=0x41d9f3e4 which is the same as cti_op_resolve_global. Things are making some sense. The offset in the str/ldr lr lines of 3118288 is huge of course. Again I think we have to ignore it. I think the offset being used is 0x40, as shown by the comment. Now lets think about the value of lr. It got set as 0x499fe5dc because of the "blx r8" that we followed earlier. Now almost immediately inside cti_op_resolve_global we call "bl", which will change the value of lr. However, lr does *not* reflect the return location for the "bl 0x41cf4aac" call. This means either: 1. We crashed before executing the bl inside cti_op_resolve_global (seems impossible), or 2. We executed the bl inside cti_op_resolve_global, and then restored lr, and returned. (seems likely) So lets go back to the code pasted at the top of this comment (around 0x499fe5dc), since thats where we're returning to. 0x499fe5dc: str r0, [r4, #3118288] ; 0x70 0x499fe5e0: str r1, [r4, #3118288] ; 0x74 Lets see if we executed those instructions: r4=0x47626688 r4 + 0x70 = 0x476266f8 (gdb) x/x 0x476266f8 0x476266f8: 0x4996e240 That matches the value of r0. Looking at the "str r1": (gdb) x/x 0x476266fc 0x476266fc: 0xfffffffb That matches the value of r1. So it seems like we have returned and executed these 2 instructions at least. Next is: 0x499fe5e4: b 0x499fc264 Lets look: (gdb) x/12i 0x499fc264 0x499fc264: mov r2, #1 0x499fc268: mvn r7, #0 0x499fc26c: ldr r0, [r4, #3118288] ; 0x50 0x499fc270: ldr r1, [r4, #3118288] ; 0x54 0x499fc274: cmn r7, #1 0x499fc278: bne 0x499fe5e8 0x499fc27c: cmn r1, #5 0x499fc280: bne 0x499fe5e8 0x499fc284: ldr r8, [r0] 0x499fc288: ldr r3, [pc, #28956432] ; 0x499fca44 0x499fc28c: cmp r8, r3 0x499fc290: bne 0x499fe5ec This code looks odd. Seems to set r7 to a fixed value and then compare its value against 1? Looking at register values and memory I'm having trouble convincing myself that this code has run, but it might have. Anyway, out of time for today unfortunately. I tried the test webpage that you provided. It doesn't trigger the crash. Also after a few runs I haven't managed to reproduce the problem where the stub offset is off by 8. Maybe that one was a bad dump.
Hojong Han
Comment 14 2012-05-01 19:37:54 PDT
I don't know exactly what's going on here but I experienced that this kind of crash, related to lr and pc values, could be occurred when cache flush was not run in the requested range.
Zoltan Herczeg
Comment 15 2012-05-02 01:39:23 PDT
> Now lets think about the value of lr. It got set as 0x499fe5dc because of the "blx r8" that we followed earlier. Now almost immediately inside cti_op_resolve_global we call "bl", which will change the value of lr. However, lr does *not* reflect the return location for the "bl 0x41cf4aac" call. This means either: > 1. We crashed before executing the bl inside cti_op_resolve_global (seems impossible), or > 2. We executed the bl inside cti_op_resolve_global, and then restored lr, and returned. (seems likely) This makes sense, and there is a third option. Actually the purpose of such stub code is allowing returning to anywhere in JIT, mainly used by exception handlers. So the return value is stored on the stack (like x86), can be changed (like a buffer overflow attack, but this is intentional here) so the c++ function can return anywhere, including a catch handler. So we have two new options: 1) A wrong handler was set 2) Something overwrites the return value Would be good to know if an exception occures just before the return... Perhaps the following code also crashes: try { var a = "a"; a++; } catch(e) { }
Daniel Drake
Comment 16 2012-05-02 09:49:09 PDT
(In reply to comment #15) > Would be good to know if an exception occures just before the return... How can I check this? > Perhaps the following code also crashes: > > try { > var a = "a"; > a++; > } catch(e) { } No crash, unfortunately. Just FYI, I have a feeling that finding a simplistic test case will be difficult. Sometimes when the crash happens, I go back to the same page and it loads just fine without crashing. gmail seems to cause the crash every time, but sometimes it takes a good few seconds longer than normal before the crash happens. Also, when I run epiphany under gdb, the crash is very hard to reproduce, even on gmail. (thats why I've been mostly working with core dumps)
Daniel Drake
Comment 17 2012-05-14 13:53:17 PDT
This has also been reproduced on a trimslice (also running as armv7hl). We'll disable the ARM JIT in Fedora for the time being in order to avoid this crash. If anyone with the right experience is interested in working on this issue, we can ship hardware. Send me an email if interested.
Simon Schampijer
Comment 18 2012-08-09 05:34:11 PDT
The workaround we were using to disable the ARM JIT in Fedora does not work anymore because the Heap code now requires JIT to be enabled (building 1.9.5). So the situation is a bit chicken and egg now. Has there been any progress on the original issue?
Stevenzengxm
Comment 19 2019-10-31 21:19:58 PDT
Comment on attachment 139221 [details] Attempted gdb diagnostics >Program terminated with signal 11, Segmentation fault. >#0 0x00000024 in ?? () >(gdb) info threads > Id Target Id Frame > 7 Thread 0x465562a0 (LWP 1582) 0x424c8a14 in nanosleep () > from /lib/libc.so.6 > 6 Thread 0x458ff2a0 (LWP 1581) 0x424f7fa8 in __GI___poll (fds=0x45a02398, > nfds=3, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:87 > 5 Thread 0x46e562a0 (LWP 1583) 0x42419ee4 in __pthread_cond_wait ( > cond=0x46564cf8, mutex=0x0) at pthread_cond_wait.c:156 > 4 Thread 0x476562a0 (LWP 1585) 0x4241a2b0 in __pthread_cond_timedwait ( > cond=0x465bea30, mutex=0x0, abstime=0x47655bc0) > at pthread_cond_timedwait.c:168 > 3 Thread 0x48edf2a0 (LWP 1627) 0x4241a2b0 in __pthread_cond_timedwait ( > cond=0x3a7438, mutex=0x0, abstime=0x48edeb88) > at pthread_cond_timedwait.c:168 > 2 Thread 0x44f812a0 (LWP 1580) 0x424f7fa8 in __GI___poll (fds=0x45000c78, > nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:87 >* 1 Thread 0x442e0000 (LWP 1579) 0x00000024 in ?? () >(gdb) bt >#0 0x00000024 in ?? () >#1 0x49f0eaf4 in ?? () >#2 0x49f0eaf4 in ?? () >Backtrace stopped: previous frame identical to this frame (corrupt stack?) >(gdb) info registers >r0 0x47657920 1197832480 >r1 0x476579f0 1197832688 >r2 0x4ecb6a20 1321953824 >r3 0x47657938 1197832504 >r4 0x47657920 1197832480 >r5 0x1ef 495 >r6 0x47657588 1197831560 >r7 0x4a0516e0 1241847520 >r8 0x41d5d15c 1104531804 >r9 0x47657570 1197831536 >r10 0x465bd400 1180423168 >r11 0x41f13060 1106325600 >r12 0x41f0fd40 1106312512 >sp 0xbe883040 0xbe883040 >lr 0x49f0eaf4 1240525556 >pc 0x24 0x24 >cpsr 0x200f0010 537853968 >(gdb) x/i 0x49f0eaf4 > 0x49f0eaf4: b 0x49f0b164 >(gdb) x/100i 0x49f0b164 > 0x49f0b164: mov r8, #0 > 0x49f0b168: str r8, [r4] > 0x49f0b16c: mvn r8, #3 > 0x49f0b170: str r8, [r4, #3118288] > 0x49f0b174: mov r8, #0 > 0x49f0b178: str r8, [r4, #3118288] > 0x49f0b17c: mvn r8, #3 > 0x49f0b180: str r8, [r4, #3118288] > 0x49f0b184: mov r8, #0 > 0x49f0b188: str r8, [r4, #3118288] > 0x49f0b18c: mvn r8, #3 > 0x49f0b190: str r8, [r4, #3118288] > 0x49f0b194: mov r8, #0 > 0x49f0b198: str r8, [r4, #3118288] > 0x49f0b19c: mvn r8, #3 > 0x49f0b1a0: str r8, [r4, #3118288] > 0x49f0b1a4: mov r8, #0 > 0x49f0b1a8: str r8, [r4, #3118288] > 0x49f0b1ac: mvn r8, #3 > 0x49f0b1b0: str r8, [r4, #3118288] ; 0x24 > 0x49f0b1b4: mov r8, #0 > 0x49f0b1b8: str r8, [r4, #3118288] ; 0x28 > 0x49f0b1bc: mvn r8, #3 > 0x49f0b1c0: str r8, [r4, #3118288] ; 0x2c > 0x49f0b1c4: mov r8, #0 > 0x49f0b1c8: str r8, [r4, #3118288] ; 0x30 > 0x49f0b1cc: mvn r8, #3 > 0x49f0b1d0: str r8, [r4, #3118288] ; 0x34 > 0x49f0b1d4: mov r8, #0 > 0x49f0b1d8: str r8, [r4, #3118288] ; 0x38 > 0x49f0b1dc: mvn r8, #3 > 0x49f0b1e0: str r8, [r4, #3118288] ; 0x3c > 0x49f0b1e4: mov r8, #0 > 0x49f0b1e8: str r8, [r4, #3118288] ; 0x40 > 0x49f0b1ec: mvn r8, #3 > 0x49f0b1f0: str r8, [r4, #3118288] ; 0x44 > 0x49f0b1f4: mov r8, #0 > 0x49f0b1f8: str r8, [r4, #3118288] ; 0x48 > 0x49f0b1fc: mvn r8, #3 > 0x49f0b200: str r8, [r4, #3118288] ; 0x4c > 0x49f0b204: mov r8, #0 > 0x49f0b208: str r8, [r4] > 0x49f0b20c: mvn r8, #5 > 0x49f0b210: str r8, [r4, #3118288] > 0x49f0b214: mov r8, #0 > 0x49f0b218: str r8, [r4, #3118288] > 0x49f0b21c: mvn r8, #5 > 0x49f0b220: str r8, [r4, #3118288] > 0x49f0b224: mov r8, #0 > 0x49f0b228: str r8, [r4, #3118288] > 0x49f0b22c: mvn r8, #5 > 0x49f0b230: str r8, [r4, #3118288] > 0x49f0b234: ldr r8, [r4, #3118288] > 0x49f0b238: cmn r8, #6 > 0x49f0b23c: bne 0x49f0b26c > 0x49f0b240: mov r0, sp > 0x49f0b244: str r4, [sp, #3118288] ; 0x60 > 0x49f0b248: mov r8, #8 > 0x49f0b24c: str r8, [r4, #-3118288] ; 0x2c > 0x49f0b250: ldr r3, [pc, #32828736] ; 0x49f0b940 > 0x49f0b254: str r4, [r3] > 0x49f0b258: ldr r8, [pc, #32828736] ; 0x49f0b944 > 0x49f0b25c: blx r8 > 0x49f0b260: str r0, [r4] > 0x49f0b264: mvn r8, #4 > 0x49f0b268: str r8, [r4, #3118288] > 0x49f0b26c: ldr r0, [r4, #-3118288] ; 0x40 > 0x49f0b270: ldr r1, [r4, #-3118288] ; 0x3c > 0x49f0b274: cmn r1, #5 > 0x49f0b278: bne 0x49f0d140 > 0x49f0b27c: ldr r8, [r0, #3118288] > 0x49f0b280: ldr r3, [pc, #32828736] ; 0x49f0b94c > 0x49f0b284: cmp r3, r8 > 0x49f0b288: ldrne pc, [pc, #32828736] ; 0x49f0b950 > 0x49f0b28c: ldr r2, [r0, #3118288] > 0x49f0b290: ldr r3, [pc, #32828736] ; 0x49f0b954 > 0x49f0b294: ldr r0, [r2, r3] > 0x49f0b298: ldr r3, [pc, #32828736] ; 0x49f0b958 > 0x49f0b29c: ldr r1, [r2, r3] > 0x49f0b2a0: str r0, [r4, #3118288] ; 0x50 > 0x49f0b2a4: str r1, [r4, #3118288] ; 0x54 > 0x49f0b2a8: nop ; (mov r0, r0) > 0x49f0b2ac: mov r1, r1 > 0x49f0b2b0: cmn r1, #2 > 0x49f0b2b4: bcc 0x49f0d17c > 0x49f0b2b8: bics r3, r0, #0 > 0x49f0b2bc: beq 0x49f0b3a4 > 0x49f0b2c0: ldr r0, [r4, #-3118288] ; 0x40 > 0x49f0b2c4: ldr r1, [r4, #-3118288] ; 0x3c > 0x49f0b2c8: cmn r1, #5 > 0x49f0b2cc: bne 0x49f0d1e4 > 0x49f0b2d0: ldr r8, [r0, #3118288] > 0x49f0b2d4: ldr r3, [pc, #32828736] ; 0x49f0b968 > 0x49f0b2d8: cmp r3, r8 > 0x49f0b2dc: ldrne pc, [pc, #32828736] ; 0x49f0b96c > 0x49f0b2e0: ldr r2, [r0, #3118288] > 0x49f0b2e4: ldr r3, [pc, #32828736] ; 0x49f0b970 > 0x49f0b2e8: ldr r0, [r2, r3] > 0x49f0b2ec: ldr r3, [pc, #32828736] ; 0x49f0b974 > 0x49f0b2f0: ldr r1, [r2, r3] >
Stevenzengxm
Comment 20 2019-10-31 21:19:59 PDT
Comment on attachment 139221 [details] Attempted gdb diagnostics >Program terminated with signal 11, Segmentation fault. >#0 0x00000024 in ?? () >(gdb) info threads > Id Target Id Frame > 7 Thread 0x465562a0 (LWP 1582) 0x424c8a14 in nanosleep () > from /lib/libc.so.6 > 6 Thread 0x458ff2a0 (LWP 1581) 0x424f7fa8 in __GI___poll (fds=0x45a02398, > nfds=3, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:87 > 5 Thread 0x46e562a0 (LWP 1583) 0x42419ee4 in __pthread_cond_wait ( > cond=0x46564cf8, mutex=0x0) at pthread_cond_wait.c:156 > 4 Thread 0x476562a0 (LWP 1585) 0x4241a2b0 in __pthread_cond_timedwait ( > cond=0x465bea30, mutex=0x0, abstime=0x47655bc0) > at pthread_cond_timedwait.c:168 > 3 Thread 0x48edf2a0 (LWP 1627) 0x4241a2b0 in __pthread_cond_timedwait ( > cond=0x3a7438, mutex=0x0, abstime=0x48edeb88) > at pthread_cond_timedwait.c:168 > 2 Thread 0x44f812a0 (LWP 1580) 0x424f7fa8 in __GI___poll (fds=0x45000c78, > nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:87 >* 1 Thread 0x442e0000 (LWP 1579) 0x00000024 in ?? () >(gdb) bt >#0 0x00000024 in ?? () >#1 0x49f0eaf4 in ?? () >#2 0x49f0eaf4 in ?? () >Backtrace stopped: previous frame identical to this frame (corrupt stack?) >(gdb) info registers >r0 0x47657920 1197832480 >r1 0x476579f0 1197832688 >r2 0x4ecb6a20 1321953824 >r3 0x47657938 1197832504 >r4 0x47657920 1197832480 >r5 0x1ef 495 >r6 0x47657588 1197831560 >r7 0x4a0516e0 1241847520 >r8 0x41d5d15c 1104531804 >r9 0x47657570 1197831536 >r10 0x465bd400 1180423168 >r11 0x41f13060 1106325600 >r12 0x41f0fd40 1106312512 >sp 0xbe883040 0xbe883040 >lr 0x49f0eaf4 1240525556 >pc 0x24 0x24 >cpsr 0x200f0010 537853968 >(gdb) x/i 0x49f0eaf4 > 0x49f0eaf4: b 0x49f0b164 >(gdb) x/100i 0x49f0b164 > 0x49f0b164: mov r8, #0 > 0x49f0b168: str r8, [r4] > 0x49f0b16c: mvn r8, #3 > 0x49f0b170: str r8, [r4, #3118288] > 0x49f0b174: mov r8, #0 > 0x49f0b178: str r8, [r4, #3118288] > 0x49f0b17c: mvn r8, #3 > 0x49f0b180: str r8, [r4, #3118288] > 0x49f0b184: mov r8, #0 > 0x49f0b188: str r8, [r4, #3118288] > 0x49f0b18c: mvn r8, #3 > 0x49f0b190: str r8, [r4, #3118288] > 0x49f0b194: mov r8, #0 > 0x49f0b198: str r8, [r4, #3118288] > 0x49f0b19c: mvn r8, #3 > 0x49f0b1a0: str r8, [r4, #3118288] > 0x49f0b1a4: mov r8, #0 > 0x49f0b1a8: str r8, [r4, #3118288] > 0x49f0b1ac: mvn r8, #3 > 0x49f0b1b0: str r8, [r4, #3118288] ; 0x24 > 0x49f0b1b4: mov r8, #0 > 0x49f0b1b8: str r8, [r4, #3118288] ; 0x28 > 0x49f0b1bc: mvn r8, #3 > 0x49f0b1c0: str r8, [r4, #3118288] ; 0x2c > 0x49f0b1c4: mov r8, #0 > 0x49f0b1c8: str r8, [r4, #3118288] ; 0x30 > 0x49f0b1cc: mvn r8, #3 > 0x49f0b1d0: str r8, [r4, #3118288] ; 0x34 > 0x49f0b1d4: mov r8, #0 > 0x49f0b1d8: str r8, [r4, #3118288] ; 0x38 > 0x49f0b1dc: mvn r8, #3 > 0x49f0b1e0: str r8, [r4, #3118288] ; 0x3c > 0x49f0b1e4: mov r8, #0 > 0x49f0b1e8: str r8, [r4, #3118288] ; 0x40 > 0x49f0b1ec: mvn r8, #3 > 0x49f0b1f0: str r8, [r4, #3118288] ; 0x44 > 0x49f0b1f4: mov r8, #0 > 0x49f0b1f8: str r8, [r4, #3118288] ; 0x48 > 0x49f0b1fc: mvn r8, #3 > 0x49f0b200: str r8, [r4, #3118288] ; 0x4c > 0x49f0b204: mov r8, #0 > 0x49f0b208: str r8, [r4] > 0x49f0b20c: mvn r8, #5 > 0x49f0b210: str r8, [r4, #3118288] > 0x49f0b214: mov r8, #0 > 0x49f0b218: str r8, [r4, #3118288] > 0x49f0b21c: mvn r8, #5 > 0x49f0b220: str r8, [r4, #3118288] > 0x49f0b224: mov r8, #0 > 0x49f0b228: str r8, [r4, #3118288] > 0x49f0b22c: mvn r8, #5 > 0x49f0b230: str r8, [r4, #3118288] > 0x49f0b234: ldr r8, [r4, #3118288] > 0x49f0b238: cmn r8, #6 > 0x49f0b23c: bne 0x49f0b26c > 0x49f0b240: mov r0, sp > 0x49f0b244: str r4, [sp, #3118288] ; 0x60 > 0x49f0b248: mov r8, #8 > 0x49f0b24c: str r8, [r4, #-3118288] ; 0x2c > 0x49f0b250: ldr r3, [pc, #32828736] ; 0x49f0b940 > 0x49f0b254: str r4, [r3] > 0x49f0b258: ldr r8, [pc, #32828736] ; 0x49f0b944 > 0x49f0b25c: blx r8 > 0x49f0b260: str r0, [r4] > 0x49f0b264: mvn r8, #4 > 0x49f0b268: str r8, [r4, #3118288] > 0x49f0b26c: ldr r0, [r4, #-3118288] ; 0x40 > 0x49f0b270: ldr r1, [r4, #-3118288] ; 0x3c > 0x49f0b274: cmn r1, #5 > 0x49f0b278: bne 0x49f0d140 > 0x49f0b27c: ldr r8, [r0, #3118288] > 0x49f0b280: ldr r3, [pc, #32828736] ; 0x49f0b94c > 0x49f0b284: cmp r3, r8 > 0x49f0b288: ldrne pc, [pc, #32828736] ; 0x49f0b950 > 0x49f0b28c: ldr r2, [r0, #3118288] > 0x49f0b290: ldr r3, [pc, #32828736] ; 0x49f0b954 > 0x49f0b294: ldr r0, [r2, r3] > 0x49f0b298: ldr r3, [pc, #32828736] ; 0x49f0b958 > 0x49f0b29c: ldr r1, [r2, r3] > 0x49f0b2a0: str r0, [r4, #3118288] ; 0x50 > 0x49f0b2a4: str r1, [r4, #3118288] ; 0x54 > 0x49f0b2a8: nop ; (mov r0, r0) > 0x49f0b2ac: mov r1, r1 > 0x49f0b2b0: cmn r1, #2 > 0x49f0b2b4: bcc 0x49f0d17c > 0x49f0b2b8: bics r3, r0, #0 > 0x49f0b2bc: beq 0x49f0b3a4 > 0x49f0b2c0: ldr r0, [r4, #-3118288] ; 0x40 > 0x49f0b2c4: ldr r1, [r4, #-3118288] ; 0x3c > 0x49f0b2c8: cmn r1, #5 > 0x49f0b2cc: bne 0x49f0d1e4 > 0x49f0b2d0: ldr r8, [r0, #3118288] > 0x49f0b2d4: ldr r3, [pc, #32828736] ; 0x49f0b968 > 0x49f0b2d8: cmp r3, r8 > 0x49f0b2dc: ldrne pc, [pc, #32828736] ; 0x49f0b96c > 0x49f0b2e0: ldr r2, [r0, #3118288] > 0x49f0b2e4: ldr r3, [pc, #32828736] ; 0x49f0b970 > 0x49f0b2e8: ldr r0, [r2, r3] > 0x49f0b2ec: ldr r3, [pc, #32828736] ; 0x49f0b974 > 0x49f0b2f0: ldr r1, [r2, r3] >
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