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Differential D97593

[msan] Use non-transparent-huge-page at SetShadow
ClosedPublic

Authored by stephan.yichao.zhao on Feb 26 2021, 3:36 PM.

Details

Reviewers
eugenis
vitalybuka
Commits
rGc0dc885d29af: [msan] Use non-transparent-huge-page at SetShadow
Summary

This prevents from getting THP ranges more and more.

Did not see any issues in practice, just found this by code review.

Diff Detail

Event Timeline

stephan.yichao.zhao requested review of this revision.Feb 26 2021, 3:36 PM
stephan.yichao.zhao created this revision.
Herald added a project: Restricted Project. · View Herald TranscriptFeb 26 2021, 3:36 PM
Herald added a subscriber: Restricted Project. · View Herald Transcript
vitalybuka accepted this revision.Feb 26 2021, 3:46 PM
vitalybuka edited reviewers, added: eugenis; removed: evghenii.
This revision is now accepted and ready to land.Feb 26 2021, 3:46 PM
eugenis accepted this revision.Feb 26 2021, 3:47 PM
This revision was landed with ongoing or failed builds.Feb 26 2021, 4:30 PM
Closed by commit rGc0dc885d29af: [msan] Use non-transparent-huge-page at SetShadow (authored by Jianzhou Zhao <jianzhouzh@google.com>). · Explain Why
This revision was automatically updated to reflect the committed changes.
Jianzhou Zhao <jianzhouzh@google.com> added a commit: rGc0dc885d29af: [msan] Use non-transparent-huge-page at SetShadow.
Harbormaster completed remote builds in B91138: Diff 326825.Feb 26 2021, 8:04 PM

Revision Contents

PathSize
compiler-rt/
lib/
msan/
2 lines

Diff 326838

compiler-rt/lib/msan/msan_poisoning.cpp

Show First 20 Lines • Show All 207 Lines • ▼ Show 20 Lines if (page_beg >= page_end) {
REAL(memset)((void *)shadow_beg, 0, shadow_end - shadow_beg); REAL(memset)((void *)shadow_beg, 0, shadow_end - shadow_beg);
} else { } else {
if (page_beg != shadow_beg) { if (page_beg != shadow_beg) {
REAL(memset)((void *)shadow_beg, 0, page_beg - shadow_beg); REAL(memset)((void *)shadow_beg, 0, page_beg - shadow_beg);
} }
if (page_end != shadow_end) { if (page_end != shadow_end) {
REAL(memset)((void *)page_end, 0, shadow_end - page_end); REAL(memset)((void *)page_end, 0, shadow_end - page_end);
} }
if (!MmapFixedNoReserve(page_beg, page_end - page_beg)) if (!MmapFixedSuperNoReserve(page_beg, page_end - page_beg))
Die(); Die();
} }
} }
} }
void SetOrigin(const void *dst, uptr size, u32 origin) { void SetOrigin(const void *dst, uptr size, u32 origin) {
// Origin mapping is 4 bytes per 4 bytes of application memory. // Origin mapping is 4 bytes per 4 bytes of application memory.
// Here we extend the range such that its left and right bounds are both // Here we extend the range such that its left and right bounds are both
Show All 25 Lines