diff options
| author | Dimitry Andric <dimitry@andric.com> | 2018-01-11 08:03:22 +0000 |
|---|---|---|
| committer | Dimitry Andric <dimitry@andric.com> | 2018-01-11 08:03:22 +0000 |
| commit | 656714a3110be7ae2a0bc8db193c0bf5b3d1ec2f (patch) | |
| tree | 826ebe09253f9ae93f44fef11623ac820be04449 | |
| parent | 45fcbf0991057d22c82d9414ec565a70a3620584 (diff) | |
| download | bcm5719-llvm-656714a3110be7ae2a0bc8db193c0bf5b3d1ec2f.tar.gz bcm5719-llvm-656714a3110be7ae2a0bc8db193c0bf5b3d1ec2f.zip | |
Fix thread race between SectionPiece's OutputOff and Live members
Summary:
As reported in bug 35788, rL316280 reintroduces a race between two
members of SectionPiece, which share the same 64 bit memory location.
To fix the race, check the hash before checking the Live member, as
suggested by Rafael.
Reviewers: ruiu, rafael
Reviewed By: ruiu
Subscribers: smeenai, emaste, llvm-commits
Differential Revision: https://reviews.llvm.org/D41884
llvm-svn: 322264
| -rw-r--r-- | lld/ELF/SyntheticSections.cpp | 4 |
1 files changed, 1 insertions, 3 deletions
diff --git a/lld/ELF/SyntheticSections.cpp b/lld/ELF/SyntheticSections.cpp index 36e3ffa284e..d274a1905c3 100644 --- a/lld/ELF/SyntheticSections.cpp +++ b/lld/ELF/SyntheticSections.cpp @@ -2451,10 +2451,8 @@ void MergeNoTailSection::finalizeContents() { parallelForEachN(0, Concurrency, [&](size_t ThreadId) { for (MergeInputSection *Sec : Sections) { for (size_t I = 0, E = Sec->Pieces.size(); I != E; ++I) { - if (!Sec->Pieces[I].Live) - continue; size_t ShardId = getShardId(Sec->Pieces[I].Hash); - if ((ShardId & (Concurrency - 1)) == ThreadId) + if ((ShardId & (Concurrency - 1)) == ThreadId && Sec->Pieces[I].Live) Sec->Pieces[I].OutputOff = Shards[ShardId].add(Sec->getData(I)); } } |
