kinst: fix memcpy() tracing crash
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Authored by christos on May 26 2023, 3:10 PM.

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Reviewers

markj
gnn

Commits

rG5c134fba225f: kinst: fix memcpy() tracing crash

Summary

Tracing memcpy() would crash the kernel, because we'd also trace the
memcpy()s called from kinst. To fix this, introduce kinst_memcpy() whose
arguments are 'volatile', so that we avoid having the compiler replace
it with a regular memcpy().

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Repository

rG FreeBSD src repository

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Build Status

Buildable 51710
Build 48601: arc lint + arc unit

Event Timeline

christos created this revision.May 26 2023, 3:10 PM

Herald added a reviewer: gnn. · View Herald TranscriptMay 26 2023, 3:10 PM

Herald added a subscriber: imp. · View Herald Transcript

christos requested review of this revision.May 26 2023, 3:10 PM

Harbormaster completed remote builds in B51709: Diff 122473.May 26 2023, 3:10 PM

christos added a child revision: D39884: kinst: port to riscv.May 26 2023, 3:11 PM

christos edited the summary of this revision. (Show Details)May 26 2023, 3:15 PM

markj added inline comments.May 26 2023, 3:17 PM

sys/cddl/dev/kinst/amd64/kinst_isa.c
485	These calls can simply be memcpy().
sys/cddl/dev/kinst/kinst.c
68	I think there's no need to have a volatile qualifier on the return type.
69	This function should have a comment explaining its existence.
sys/cddl/dev/kinst/trampoline.c
57 ↗	(On Diff #122473)	This can be regular memcpy().