[stdlib] AtomicWaitQueue crashes on Arm 32 bit #59043

colemancda · 2022-05-24T05:45:39Z

Describe the bug
Swift's runtime crashes in AtomicWaitQueue.createNewQueue when accessing metadata during initialization.

To Reproduce
Steps to reproduce the behavior:

Run ./build.sh with SWIFT_BUILD_CONFIGURATION=Debug to cross compile swift-hello and the Swift runtime libraries for Debian 11 with debug info.
Run swift-hello with LLDB or GDB.

Expected behavior
Should not crash. Using the same scripts to cross compile Swift but setting SWIFT_VERSION=5.5.3 and using a Swift 5.5.3 compiler, the program does not crash. This is a regression for Swift 5.6.1.

Environment (please complete the following information):

OS: Debian 11 Armhf (armv7)
Swift 5.6.1 runtime cross compiled with
https://github.com/colemancda/swift-armv7
Swift 5.6.1 compiler from official Swift 5.6.1 Ubuntu Docker image
Docker environment to build
https://hub.docker.com/layers/swift-armv7/colemancda/swift-armv7/amd64-prebuilt/images/sha256-5416cdf242a46a3fa580e8b919699461137a2adf85bdf7d6f693d117adb8b6dc?context=explore

Additional context
Here is a debug stack trace with LLDB.

Process 500215 launched: '/home/coleman/Developer/swift-armv7/build/swift-hello/armv7-unknown-linux-gnueabihf/debug/swift-hello' (arm)
Process 500215 stopped
* thread #1, name = 'swift-hello', stop reason = signal SIGBUS: illegal alignment
    frame #0: 0xf7d90688 libswiftCore.so`swift::MetadataWaitQueue* swift::AtomicWaitQueue<swift::MetadataWaitQueue, swift::IndirectMutex>::Worker::createNewQueue<>() at AtomicWaitQueue.h:427:24
   424    private:
   425      template <class... Args>
   426      static Impl *createNewQueue(Args &&...args) {
-> 427        auto queue = new Impl(std::forward<Args>(args)...);
   428        queue->WaitQueueLock.lock();
   429        return queue;
   430      }
(lldb) thread backtrace
* thread #1, name = 'swift-hello', stop reason = signal SIGBUS: illegal alignment
  * frame #0: 0xf7d90688 libswiftCore.so`swift::MetadataWaitQueue* swift::AtomicWaitQueue<swift::MetadataWaitQueue, swift::IndirectMutex>::Worker::createNewQueue<>() at AtomicWaitQueue.h:427:24
    frame #1: 0xf7d905b4 libswiftCore.so`swift::MetadataWaitQueue* swift::AtomicWaitQueue<swift::MetadataWaitQueue, swift::IndirectMutex>::Worker::createQueue<>(this=0xfffeaf0c) at AtomicWaitQueue.h:260:24
    frame #2: 0xf7d90536 libswiftCore.so`swift::PrivateMetadataTrackingInfo::initial(worker=0xfffeaf0c, initialState=Allocating) at MetadataCache.h:707:63
    frame #3: 0xf7d7100c libswiftCore.so`swift::MetadataCacheEntryBase<(anonymous namespace)::GenericCacheEntry, void const*>::MetadataCacheEntryBase(this=0xf7f1f1c0, worker=0xfffeaf0c, initialState=Allocating) at MetadataCache.h:904:22
    frame #4: 0xf7d70f6c libswiftCore.so`swift::VariadicMetadataCacheEntryBase<(anonymous namespace)::GenericCacheEntry>::VariadicMetadataCacheEntryBase(this=0xf7f1f1c0, key=0xfffeac4c, worker=0xfffeaf0c, initialState=Allocating, value=0x00000000) at MetadataCache.h:1366:9
    frame #5: 0xf7d738ae libswiftCore.so`(anonymous namespace)::GenericCacheEntry::GenericCacheEntry(this=0xf7f1f1c0, key=MetadataCacheKey @ 0xfffeac4c, worker=0xfffeaf0c, request=MetadataRequest @ 0xfffeac48, description=0xf7e39b9c, arguments=0xfffeafc4) at Metadata.cpp:293:9
    frame #6: 0xf7d73822 libswiftCore.so`std::pair<(anonymous namespace)::GenericCacheEntry*, bool> swift::StableAddressConcurrentReadableHashMap<(anonymous namespace)::GenericCacheEntry, swift::TaggedMetadataAllocator<(this=0xfffeadc4, wrapper=0x004631ac, created=true)14>, swift::IndirectMutex>::getOrInsert<swift::MetadataCacheKey, swift::MetadataWaitQueue::Worker&, swift::MetadataRequest&, swift::TargetTypeContextDescriptor<swift::InProcess> const*&, void const* const*&>(swift::MetadataCacheKey, swift::MetadataWaitQueue::Worker&, swift::MetadataRequest&, swift::TargetTypeContextDescriptor<swift::InProcess> const*&, void const* const*&)::'lambda'(swift::HashMapElementWrapper<(anonymous namespace)::GenericCacheEntry>*, bool)::operator()(swift::HashMapElementWrapper<(anonymous namespace)::GenericCacheEntry>*, bool) const at Concurrent.h:1211:26
    frame #7: 0xf7d73660 libswiftCore.so`void swift::ConcurrentReadableHashMap<swift::HashMapElementWrapper<(anonymous namespace)::GenericCacheEntry>, swift::IndirectMutex>::getOrInsert<swift::MetadataCacheKey, std::pair<(anonymous namespace)::GenericCacheEntry*, bool> swift::StableAddressConcurrentReadableHashMap<(this=0xf7f1eb38, key=MetadataCacheKey @ 0xfffead58, call=0xfffeadc4)::GenericCacheEntry, swift::TaggedMetadataAllocator<(unsigned short)14>, swift::IndirectMutex>::getOrInsert<swift::MetadataCacheKey, swift::MetadataWaitQueue::Worker&, swift::MetadataRequest&, swift::TargetTypeContextDescriptor<swift::InProcess> const*&, void const* const*&>(swift::MetadataCacheKey, swift::MetadataWaitQueue::Worker&, swift::MetadataRequest&, swift::TargetTypeContextDescriptor<swift::InProcess> const*&, void const* const*&)::'lambda'(swift::HashMapElementWrapper<(anonymous namespace)::GenericCacheEntry>*, bool)>(swift::MetadataCacheKey, swift::MetadataWaitQueue::Worker& const&) at Concurrent.h:1116:17
    frame #8: 0xf7d7344e libswiftCore.so`std::pair<(anonymous namespace)::GenericCacheEntry*, bool> swift::StableAddressConcurrentReadableHashMap<(anonymous namespace)::GenericCacheEntry, swift::TaggedMetadataAllocator<(this=0xf7f1eb38, key=MetadataCacheKey @ 0xfffeae1c, args=0xfffeaf0c, args=0xfffeaf84, args=0xfffeaf7c, args=0xfffeaf80)14>, swift::IndirectMutex>::getOrInsert<swift::MetadataCacheKey, swift::MetadataWaitQueue::Worker&, swift::MetadataRequest&, swift::TargetTypeContextDescriptor<swift::InProcess> const*&, void const* const*&>(swift::MetadataCacheKey, swift::MetadataWaitQueue::Worker&, swift::MetadataRequest&, swift::TargetTypeContextDescriptor<swift::InProcess> const*&, void const* const*&) at Concurrent.h:1204:9
    frame #9: 0xf7d730ee libswiftCore.so`std::pair<(anonymous namespace)::GenericCacheEntry*, bool> swift::LockingConcurrentMapStorage<(anonymous namespace)::GenericCacheEntry, (this=0xf7f1eb38, key=MetadataCacheKey @ 0xfffeae5c, args=0xfffeaf0c, args=0xfffeaf84, args=0xfffeaf7c, args=0xfffeaf80)14>::getOrInsert<swift::MetadataCacheKey, swift::MetadataWaitQueue::Worker&, swift::MetadataRequest&, swift::TargetTypeContextDescriptor<swift::InProcess> const*&, void const* const*&>(swift::MetadataCacheKey, swift::MetadataWaitQueue::Worker&, swift::MetadataRequest&, swift::TargetTypeContextDescriptor<swift::InProcess> const*&, void const* const*&) at MetadataCache.h:184:16
    frame #10: 0xf7d72f8e libswiftCore.so`std::pair<(anonymous namespace)::GenericCacheEntry*, swift::MetadataResponse> swift::LockingConcurrentMap<(anonymous namespace)::GenericCacheEntry, swift::LockingConcurrentMapStorage<(this=0xf7f1eb38, key=MetadataCacheKey @ 0xfffeaf1c, args=0xfffeaf84, args=0xfffeaf7c, args=0xfffeaf80)::GenericCacheEntry, (unsigned short)14> >::getOrInsert<swift::MetadataCacheKey, swift::MetadataRequest&, swift::TargetTypeContextDescriptor<swift::InProcess> const*&, void const* const*&>(swift::MetadataCacheKey, swift::MetadataRequest&, swift::TargetTypeContextDescriptor<swift::InProcess> const*&, void const* const*&) at MetadataCache.h:247:27
    frame #11: 0xf7d6aeb6 libswiftCore.so`_swift_getGenericMetadata(request=MetadataRequest @ 0xfffeaf84, arguments=0xfffeafc4, description=0xf7e39b9c) at Metadata.cpp:815:23
    frame #12: 0xf7d6ae22 libswiftCore.so`::swift_getGenericMetadata(request=MetadataRequest @ 0xfffeafa4, arguments=0xfffeafc4, description=0xf7e39b9c) at Metadata.cpp:827:10
    frame #13: 0xf7d3a3cc libswiftCore.so`__swift_instantiateGenericMetadata at <compiler-generated>:0
    frame #14: 0xf7bc82b8 libswiftCore.so`$sSRMa at <compiler-generated>:0
    frame #15: 0xf7db336e libswiftCore.so`swift::MetadataAccessFunction::operator(this=0xfffeb0a8, request=MetadataRequest @ 0xfffeaffc, arg0=0xf7e0d5b8)(swift::MetadataRequest, void const*) const at Metadata.h:3721:12
    frame #16: 0xf7db20ac libswiftCore.so`swift::MetadataAccessFunction::operator(this=0xfffeb0a8, request=MetadataRequest @ 0xfffeb054, args=ArrayRef<const void *> @ 0xfffeb04c)(swift::MetadataRequest, __swift::__runtime::llvm::ArrayRef<void const*>) const at Metadata.h:3700:14
    frame #17: 0xf7da6fb4 libswiftCore.so`(anonymous namespace)::DecodedMetadataBuilder::createBoundGenericType(this=0xfffedcdc, anyTypeDecl=0xf7e39b9c, genericArgs=ArrayRef<const swift::TargetMetadata<swift::InProcess> *> @ 0xfffeb134, parent=0x00000000) const at MetadataLookup.cpp:1451:12
    frame #18: 0xf7da1f54 libswiftCore.so`swift::Demangle::__runtime::TypeDecoder<(anonymous namespace)::DecodedMetadataBuilder>::decodeMangledType(this=0xfffedc3c, Node=0xfffee0e0, depth=1, forRequirement=false) at TypeDecoder.h:578:22
    frame #19: 0xf7da1a32 libswiftCore.so`swift::Demangle::__runtime::TypeDecoder<(anonymous namespace)::DecodedMetadataBuilder>::decodeMangledType(this=0xfffedc3c, Node=0xfffee0f8, depth=0, forRequirement=false) at TypeDecoder.h:508:14
    frame #20: 0xf7da146c libswiftCore.so`swift::Demangle::__runtime::TypeDecoder<(anonymous namespace)::DecodedMetadataBuilder>::decodeMangledType(this=0xfffedc3c, Node=0xfffee0f8, forRequirement=false) at TypeDecoder.h:477:12
    frame #21: 0xf7da13fa libswiftCore.so`swift::TypeLookupErrorOr<(anonymous namespace)::DecodedMetadataBuilder::BuiltType> swift::Demangle::__runtime::decodeMangledType<(anonymous namespace)::DecodedMetadataBuilder>(Builder=0xfffedcdc, Node=0xfffee0f8, forRequirement=false)::DecodedMetadataBuilder&, swift::Demangle::__runtime::Node*, bool) at TypeDecoder.h:1567:8
    frame #22: 0xf7d9ec14 libswiftCore.so`swift_getTypeByMangledNodeImpl(request=MetadataRequest @ 0xfffedd30, demangler=0xfffede48, node=0xfffee0f8, origArgumentVector=0x00000000, substGenericParam=swift::SubstGenericParameterFn @ 0xfffedd44, substWitnessTable=swift::SubstDependentWitnessTableFn @ 0xfffedd48)>, std::function<swift::TargetWitnessTable<swift::InProcess> const* (swift::TargetMetadata<swift::InProcess> const*, unsigned int)>) at MetadataLookup.cpp:1737:15
    frame #23: 0xf7d9eb54 libswiftCore.so`::swift_getTypeByMangledNode(request=MetadataRequest @ 0xfffedd98, demangler=0xfffede48, node=0xfffee0f8, arguments=0x00000000, substGenericParam=swift::SubstGenericParameterFn @ 0xfffeddb4, substWitnessTable=swift::SubstDependentWitnessTableFn @ 0xfffeddb8) at CompatibilityOverrideRuntime.def:149:1
    frame #24: 0xf7d9edda libswiftCore.so`swift_getTypeByMangledNameImpl(request=MetadataRequest @ 0xfffee778, typeName=(Data = "SRy\U00000001\xe8\xe1`", Length = 9), origArgumentVector=0x00000000, substGenericParam=swift::SubstGenericParameterFn @ 0xfffee794, substWitnessTable=swift::SubstDependentWitnessTableFn @ 0xfffee798)>, std::function<swift::TargetWitnessTable<swift::InProcess> const* (swift::TargetMetadata<swift::InProcess> const*, unsigned int)>) at MetadataLookup.cpp:1801:10
    frame #25: 0xf7d9d620 libswiftCore.so`::swift_getTypeByMangledName(request=MetadataRequest @ 0xfffee7f0, typeName=(Data = "SRy\U00000001\xe8\xe1`", Length = 9), arguments=0x00000000, substGenericParam=swift::SubstGenericParameterFn @ 0xfffee80c, substWitnessTable=swift::SubstDependentWitnessTableFn @ 0xfffee810) at CompatibilityOverrideRuntime.def:157:1
    frame #26: 0xf7d9d88a libswiftCore.so`::swift_getTypeByMangledNameInContext(typeNameStart="SRy\U00000001\xe8\xe1`", typeNameLength=9, context=0x00000000, genericArgs=0x00000000) at MetadataLookup.cpp:1854:10
    frame #27: 0xf7a25e34 libswiftCore.so`__swift_instantiateConcreteTypeFromMangledName at <compiler-generated>:0
    frame #28: 0xf7a46c9c libswiftCore.so`$ss12_SmallStringVyABSgSRys5UInt8VGcfC at SmallString.swift:273:14
    frame #29: 0xf786a064 libswiftCore.so`$sSS21_builtinStringLiteral17utf8CodeUnitCount7isASCIISSBp_BwBi1_tcfC at String.swift:652:19
    frame #30: 0xf70c5b84 libFoundation.so`$s10Foundation19__CFInitializeSwiftyyF + 36
    frame #31: 0xf70c5b5c libFoundation.so`__CFInitializeSwift + 12
    frame #32: 0xf72a1886 libFoundation.so`__CFInitialize at CFRuntime.c:1247:9
    frame #33: 0xf7fd0f40 ld-2.31.so`call_init(l=<unavailable>, argc=1, argv=0xfffef664, env=0xfffef66c) at dl-init.c:72:3
    frame #34: 0xf7fd0fe2 ld-2.31.so`_dl_init at dl-init.c:30:6
    frame #35: 0xf7fd0fd4 ld-2.31.so`_dl_init(main_map=0xf7fef9b8, argc=1, argv=0xfffef664, env=0xfffef66c) at dl-init.c:119
    frame #36: 0xf7fc5ac4 ld-2.31.so`_dl_start_user + 52
(lldb)

The text was updated successfully, but these errors were encountered:

tbkka · 2022-05-24T15:10:22Z

CC: @lorentey @grynspan

grynspan · 2022-05-24T16:47:53Z

This issue should be fixed with my changes to make this function use swift_cxx_newObject() instead of operator new. Did that change get rolled back?

grynspan · 2022-05-24T16:53:27Z

My change appears to still be present on main. This line from the crash:

auto queue = new Impl(std::forward<Args>(args)...);

Is now:

auto queue = swift_cxx_newObject<Impl>(std::forward<Args>(args)...);

And swift_cxx_newObject<T>() correctly allocates instances of type T when T's alignment exceeds the default.

Could it be that lowering SWIFT_VERSION is somehow causing things to use the old Swift runtime, or a mixed and incompatible environment?

@compnerd and @buttaface for visibility as they were also working on alignment of types for Android/Windows.

finagolfin · 2022-05-24T18:37:54Z

Could it be that lowering SWIFT_VERSION is somehow causing things to use the old Swift runtime, or a mixed and incompatible environment?

@grynspan, your change was never merged back to Swift 5.6, which is what he is testing.

@colemancda, you are seeing this with all Swift executables running on Debian armhf?

This could be related to another metadata crash I reported in a NIO test on Android armv7, #58307, though most Android armv7 executables run fine for me.

colemancda · 2022-05-24T18:44:46Z

No, the 5.5 runtime won't compile with 5.6 compiler and vice versa. That AtomicWaitQueue type is new to the 5.6 runtime. I also wanna note that if I compile the 5.6 Stdlib in release mode and run with qemu-arm-static, it runs and only crashes once every 20 tries.

grynspan · 2022-05-24T18:49:09Z

@buttaface D'oh! Well, if my change was never merged back, then… this issue is resolved in a future Swift version, I guess?

finagolfin · 2022-05-24T19:01:25Z

if I compile the 5.6 Stdlib in release mode and run with qemu-arm-static, it runs and only crashes once every 20 tries.

Oh, I missed that you are mostly only seeing this with a Debug build. I haven't built the Debug 5.6 stdlib for armv7, only Release.

Try backporting his pull #42355 to 5.6, maybe that will fix it?

colemancda · 2022-05-27T02:19:53Z

Adding the patch for #42355 into 5.6.1 release seems to have fixed it. Now I have a crash in the Concurrency module, but that is already filed under another bug.

#58151 (comment)

colemancda · 2022-05-27T02:25:05Z

Added patches

colemancda/swift-armv7@eb9bf39
https://gist.github.com/colemancda/d88a775f2bf3e234f4fa705c46b66b37

colemancda · 2022-05-27T02:26:49Z

@grynspan Thanks for the fix!

grynspan · 2022-05-27T17:55:46Z

@colemancda Happy to help!

colemancda added the bug A deviation from expected or documented behavior. Also: expected but undesirable behavior. label May 24, 2022

colemancda closed this as completed May 27, 2022

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

[stdlib] AtomicWaitQueue crashes on Arm 32 bit #59043

[stdlib] AtomicWaitQueue crashes on Arm 32 bit #59043

colemancda commented May 24, 2022 •

edited

Loading

tbkka commented May 24, 2022

grynspan commented May 24, 2022

grynspan commented May 24, 2022

finagolfin commented May 24, 2022

colemancda commented May 24, 2022

grynspan commented May 24, 2022

finagolfin commented May 24, 2022

colemancda commented May 27, 2022 •

edited

Loading

colemancda commented May 27, 2022

colemancda commented May 27, 2022

grynspan commented May 27, 2022

[stdlib] AtomicWaitQueue crashes on Arm 32 bit #59043

[stdlib] AtomicWaitQueue crashes on Arm 32 bit #59043

Comments

colemancda commented May 24, 2022 • edited Loading

tbkka commented May 24, 2022

grynspan commented May 24, 2022

grynspan commented May 24, 2022

finagolfin commented May 24, 2022

colemancda commented May 24, 2022

grynspan commented May 24, 2022

finagolfin commented May 24, 2022

colemancda commented May 27, 2022 • edited Loading

colemancda commented May 27, 2022

colemancda commented May 27, 2022

grynspan commented May 27, 2022

colemancda commented May 24, 2022 •

edited

Loading

colemancda commented May 27, 2022 •

edited

Loading