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[hwasan] Remove untagging of kernel-consumed memory
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Authored by hctim on Apr 22 2021, 5:37 PM.

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Summary

Now that page aliasing for x64 has landed, we don't need to worry about
passing tagged pointers to libc, and thus D98875 removed it.
Unfortunately, we still test on aarch64 devices that don't have the
kernel tagged address ABI (https://reviews.llvm.org/D98875#2649269).

All the memory that we pass to the kernel in these tests is from global
variables. Instead of having architecture-specific untagging mechanisms
for this memory, let's just not tag the globals.

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Event Timeline

hctim created this revision.Apr 22 2021, 5:37 PM
hctim requested review of this revision.Apr 22 2021, 5:37 PM
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hctim retitled this revision from Summary: Now that page aliasing for x64 has landed, we don't need to worry about passing tagged pointers to libc, and thus D98875 removed it. Unfortunately, we still test on aarch64 devices that don't have the kernel tagged address ABI (https... to [hwasan] Remove untagging of kernel-consumed memory.Apr 22 2021, 5:38 PM
hctim edited the summary of this revision. (Show Details)
This revision is now accepted and ready to land.Apr 23 2021, 7:56 AM
This revision was automatically updated to reflect the committed changes.