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Diffstat (limited to 'results/scraper/fex/4301')
| -rw-r--r-- | results/scraper/fex/4301 | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/results/scraper/fex/4301 b/results/scraper/fex/4301 new file mode 100644 index 000000000..b55a1aba4 --- /dev/null +++ b/results/scraper/fex/4301 @@ -0,0 +1,46 @@ +Investigate whether dynamic linking triggers spurious allocations +EDIT (neobrain): The original observation stem from an invalid CI configuration. It's unconfirmed at this point whether dynamic linking incurs any spurious allocations. Original observation follows: + +<hr> + +#5476 uncovered this issue using the glibc fault CI test. A runner happened to have libxxhash-dev installed, which causes symbol lookup to happen dynamically, which causes glibc allocations. +``` +Program terminated with signal SIGILL, Illegal instruction. +#0 FEXCore::Assert::ForcedAssert () at /home/ryanh/FEX/FEXCore/Source/Utils/ForcedAssert.cpp:9 +9 asm volatile("hlt #1"); +(gdb) y +Undefined command: "y". Try "help". +(gdb) bt +#0 FEXCore::Assert::ForcedAssert () at /home/ryanh/FEX/FEXCore/Source/Utils/ForcedAssert.cpp:9 +#1 0x0000aaaac2ac23f0 in FEXCore::Allocator::EvaluateReturnAddress (Return=0xffffbb8c0ed4 <__GI__dl_exception_create_format+244>) at /home/ryanh/FEX/FEXCore/Source/Utils/AllocatorOverride.cpp:114 +#2 0x0000aaaac2ac20e4 in fault_malloc (size=56) at /home/ryanh/FEX/FEXCore/Source/Utils/AllocatorOverride.cpp:130 +#3 0x0000ffffbb8c0ed4 in malloc (size=56) at ../include/rtld-malloc.h:56 +#4 __GI__dl_exception_create_format (exception=exception@entry=0xffffeda66d68, objname=0xffffeda6c721 "./Bin/FEXLoader", fmt=fmt@entry=0xffffbb8df4d0 "undefined symbol: %s%s%s") at ./elf/dl-exception.c:157 +#5 0x0000ffffbb8c74a8 in _dl_lookup_symbol_x (undef_name=0xaaaac2508f06 "XXH3_64bits", undef_map=undef_map@entry=0xffffbb8fa370, ref=ref@entry=0xffffeda66dd8, symbol_scope=<optimized out>, version=0xffffbb8bb018, type_class=type_class@entry=1, + flags=1, skip_map=skip_map@entry=0x0) at ./elf/dl-lookup.c:877 +#6 0x0000ffffbb8cd080 in _dl_fixup (l=0xffffbb8fa370, reloc_arg=3504) at ./elf/dl-runtime.c:95 +#7 0x0000ffffbb8cf1ac in _dl_runtime_resolve () at ../sysdeps/aarch64/dl-trampoline.S:100 +#8 0x0000aaaac2794140 in FEXCore::IR::AOTIRCaptureCache::LoadAOTIRCacheEntry (this=0xffffbae70568, filename="/home/ryanh/.fex-emu/RootFS/Ubuntu_22_04/usr/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2") + at /home/ryanh/FEX/FEXCore/Source/Interface/IR/AOTIR.cpp:384 +#9 0x0000aaaac2662414 in FEXCore::Context::ContextImpl::LoadAOTIRCacheEntry (this=0xffffbae70000, filename="/home/ryanh/.fex-emu/RootFS/Ubuntu_22_04/usr/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2") + at /home/ryanh/FEX/FEXCore/Source/Interface/Core/Core.cpp:1054 +#10 0x0000aaaac28d6d64 in FEX::HLE::SyscallHandler::TrackMmap (this=0xffffbae70800, Thread=0x0, Base=140737352839168, Size=8192, Prot=1, Flags=2066, fd=6, Offset=0) + at /home/ryanh/FEX/Source/Tools/LinuxEmulation/LinuxSyscalls/SyscallsSMCTracking.cpp:214 +#11 0x0000aaaac2948e68 in FEX::HLE::x64::x64SyscallHandler::GuestMmap (this=0xffffbae70800, Thread=0x0, addr=0x7ffff7ec3000, length=8192, prot=1, flags=2066, fd=6, offset=0) + at /home/ryanh/FEX/Source/Tools/LinuxEmulation/LinuxSyscalls/x64/Memory.cpp:41 +#12 0x0000aaaac2645888 in ELFCodeLoader::MapFile (this=0xffffeda6afa0, file=..., Base=140737352839168, Header=..., prot=1, flags=2066, Handler=0xffffbae70800) at /home/ryanh/FEX/Source/Tools/FEXLoader/ELFCodeLoader.h:81 +#13 0x0000aaaac2644d24 in ELFCodeLoader::LoadElfFile (this=0xffffeda6afa0, Elf=..., BrkBase=0x0, Handler=0xffffbae70800, LoadHint=0) at /home/ryanh/FEX/Source/Tools/FEXLoader/ELFCodeLoader.h:147 +#14 0x0000aaaac26343a4 in ELFCodeLoader::MapMemory (this=0xffffeda6afa0, Handler=0xffffbae70800) at /home/ryanh/FEX/Source/Tools/FEXLoader/ELFCodeLoader.h:472 +#15 0x0000aaaac262e688 in main (argc=7, argv=0xffffeda6b798, envp=0xffffeda6b7d8) at /home/ryanh/FEX/Source/Tools/FEXLoader/FEXLoader.cpp:567 +(gdb) frame 8 +#8 0x0000aaaac2794140 in FEXCore::IR::AOTIRCaptureCache::LoadAOTIRCacheEntry (this=0xffffbae70568, filename="/home/ryanh/.fex-emu/RootFS/Ubuntu_22_04/usr/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2") + at /home/ryanh/FEX/FEXCore/Source/Interface/IR/AOTIR.cpp:384 +384 auto filename_hash = XXH3_64bits(filename.c_str(), filename.size()); +(gdb) +``` + +We can not dynamically link xxhash at the very least. We should double check our other dependencies to ensure we don't hit dynamic linking. + +At the end of the day we should only dynamically link against PT_INTERP, libc, libgcc_s, libm, and libstdc++. + +Ideally we could also get rid of libstdc++ but I'm not sure if that's viable when doing dlopen against C++ libraries? Would need a bit more investigation for that one. \ No newline at end of file |