1646045 - Assertion failure: fallibleScope_ ([OOM] Cannot allocate a new chunk in an infallible scope.), at ds/LifoAlloc.cpp:173

Status: VERIFIED FIXED

(Core :: JavaScript Engine, defect)

Description

[Christian Holler (:decoder)]

The following testcase crashes on mozilla-central revision 20200615-f05a0084c5f2 (debug build, run with --fuzzing-safe --cpu-count=2 --ion-offthread-compile=off --disable-oom-functions --disable-oom-functions --ion-check-range-analysis --ion-full-warmup-threshold=0 --more-compartments --baseline-eager):

See attachment.

Backtrace:

received signal SIGSEGV, Segmentation fault.
0x0000555555faf245 in js::LifoAlloc::newChunkWithCapacity(unsigned long, bool) ()
#0  0x0000555555faf245 in js::LifoAlloc::newChunkWithCapacity(unsigned long, bool) ()
#1  0x0000555555faf441 in js::LifoAlloc::getOrCreateChunk(unsigned long) ()
#2  0x0000555555faf7bb in js::LifoAlloc::allocImplColdPath(unsigned long) ()
#3  0x000055555646d8bf in js::jit::TempAllocator::allocateInfallible(unsigned long) ()
#4  0x0000555556675df3 in js::jit::FoldLoadsWithUnbox(js::jit::MIRGenerator*, js::jit::MIRGraph&) ()
#5  0x000055555666e247 in js::jit::OptimizeMIR(js::jit::MIRGenerator*) ()
#6  0x0000555556677ae9 in js::jit::CompileBackEnd(js::jit::MIRGenerator*, js::jit::WarpSnapshot*) ()
#7  0x000055555668be61 in js::jit::IonCompile(JSContext*, JS::Handle<JSScript*>, js::jit::BaselineFrame*, unsigned int, unsigned char*, bool, js::jit::OptimizationLevel) ()
#8  0x0000555556678f81 in js::jit::Compile(JSContext*, JS::Handle<JSScript*>, js::jit::BaselineFrame*, unsigned int, unsigned char*, bool) ()
#9  0x00005555566796e7 in IonCompileScriptForBaseline(JSContext*, js::jit::BaselineFrame*, unsigned int, unsigned char*) ()
#10 0x00000fe8d5302875 in ?? ()
[...]
#60 0x0000000000000000 in ?? ()
rax	0x5555570b6092	93825020944530
rbx	0x7ffff53c2510	140737307747600
rcx	0x5555583de980	93825041033600
rdx	0x0	0
rsi	0x7ffff7105770	140737338431344
rdi	0x7ffff7104540	140737338426688
rbp	0x7fffffffa5a0	140737488332192
rsp	0x7fffffffa580	140737488332160
r8	0x7ffff7105770	140737338431344
r9	0x7ffff7f9bd40	140737353727296
r10	0x58	88
r11	0x7ffff6dac7a0	140737334921120
r12	0x7ffff4fbb958	140737303525720
r13	0x7ffff4fb43d8	140737303495640
r14	0x7fffffffa5f0	140737488332272
r15	0x7ffff53c2510	140737307747600
rip	0x555555faf245 <js::LifoAlloc::newChunkWithCapacity(unsigned long, bool)+325>
=> 0x555555faf245 <_ZN2js9LifoAlloc20newChunkWithCapacityEmb+325>:	movl   $0xad,0x0
   0x555555faf250 <_ZN2js9LifoAlloc20newChunkWithCapacityEmb+336>:	callq  0x555555849bee <abort>

This bug was really hard to reduce and won't reduce further. It would be good to tackle this while it still reproduces, it seems to be fragile, but the fuzzer still hits it quite often. Must be a recent regression.

Comment 1

[Christian Holler (:decoder)]

Attachment: Testcase

Comment 2

[Iain Ireland [:iain]]

Looks like FoldLoadsWithUnbox needs an ensureBallast. I'll put up a patch.

Comment 3

[Iain Ireland [:iain]]

Attachment: Bug 1646045: Add ensureBallast to FoldLoadsWithUnbox r=jandem

Comment 4

[Jason Kratzer [:jkratzer]]

Bugmon Analysis:
Verified bug as reproducible on mozilla-central 20200616154959-89a54069f124.
The bug appears to have been introduced in the following build range:
> Start: 5f052981c734c4d888e139f289cbcfc21217afc1 (20200527150323)
> End: abab86b25b5f76406c11bdde1b0823990713efee (20200527150449)
> Pushlog: https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=5f052981c734c4d888e139f289cbcfc21217afc1&tochange=abab86b25b5f76406c11bdde1b0823990713efee

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/6de6943d856f
Add ensureBallast to FoldLoadsWithUnbox r=jandem

Comment 6

[Alexandru Michis [:malexandru]]

Backed out changeset 6de6943d856f for causing failures in test_notification_openWindow.html

Backout link: https://hg.mozilla.org/integration/autoland/rev/5bcc680a02d8b0236ebc1a9d7b0ae8fc85d9a9cb

Push with failures: https://treeherder.mozilla.org/#/jobs?repo=autoland&group_state=expanded&searchStr=linux%2C18.04%2Cx64%2Cwebrender%2Cdebug%2Cmochitests%2Cwith%2Cfission%2Cenabled%2Ctest-linux1804-64-qr%2Fdebug-mochitest-plain-fis-e10s-11%2Cm-fis%2811%29&tochange=36790714faf25ec3d846485ef046e0efbe9e6c87&fromchange=fa6512a9584891f866030fe0d70abbf4d86f7451

Failure log: https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=306680403&repo=autoland&lineNumber=3364

Comment 7

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/45512060bc9d
Add ensureBallast to FoldLoadsWithUnbox r=jandem DONTBUILD

Comment 8

[Alexandru Michis [:malexandru]]

Re-landed changeset 6de6943d856f since it was not the cause of the failures, re-land link:
https://hg.mozilla.org/integration/autoland/rev/45512060bc9dd0d6b072d7a8c530de849c4b49c9

Sorry for the inconvenience!

Comment 9

[Cristian Brindusan [:cbrindusan]]

https://hg.mozilla.org/mozilla-central/rev/6de6943d856f

Comment 10

[Alexandru Michis [:malexandru]]

https://hg.mozilla.org/mozilla-central/rev/45512060bc9d

Comment 11

[Jason Kratzer [:jkratzer]]

Bugmon Analysis:
Verified bug as fixed on rev mozilla-central 20200618094105-f291dd9e075c.
Removing bugmon keyword as no further action possible.
Please review the bug and re-add the keyword for further analysis.