Module Name: src
Committed By: maxv
Date: Sat May 18 13:32:12 UTC 2019
Modified Files:
src/sys/arch/amd64/amd64: amd64_trap.S locore.S
src/sys/arch/amd64/include: frameasm.h
Log Message:
Two changes in the CPU mitigations:
* Micro-optimize: put every mitigation in the same branch. This removes
two branches in each exc/int return path, and removes all branches in
the syscall return path.
* Modify the SpectreV2 mitigation to be compatible with SpectreV4. I
recently realized that both couldn't be enabled at the same time on
Intel. This is because initially, when there was just SpectreV2, we
could reset the whole IA32_SPEC_CTRL MSR. But then Intel added another
bit in it for SpectreV4, so it isn't right to reset it entirely
anymore. SSBD needs to stay.
To generate a diff of this commit:
cvs rdiff -u -r1.47 -r1.48 src/sys/arch/amd64/amd64/amd64_trap.S
cvs rdiff -u -r1.184 -r1.185 src/sys/arch/amd64/amd64/locore.S
cvs rdiff -u -r1.43 -r1.44 src/sys/arch/amd64/include/frameasm.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
