CVS commit: src/sys

["Maxime Villard" <maxv%netbsd.org@localhost>]

Module Name:    src
Committed By:   maxv
Date:           Sun Mar 24 15:58:32 UTC 2019

Modified Files:
        src/sys/arch/amd64/amd64: machdep.c netbsd32_machdep.c
        src/sys/compat/linux32/arch/amd64: linux32_machdep.c

Log Message:
Disable preemption when setting PCB_COMPAT32, to prevent a context switch
before cpu_fsgs_reload() finishes, otherwise we write garbage in the GDT.
On NetBSD-current it is harmless, however in NetBSD-8 it might cause
panics, because NetBSD-8 uses the old SegRegs model and under this model
we reload %fs and %gs during switches.


To generate a diff of this commit:
cvs rdiff -u -r1.328 -r1.329 src/sys/arch/amd64/amd64/machdep.c
cvs rdiff -u -r1.119 -r1.120 src/sys/arch/amd64/amd64/netbsd32_machdep.c
cvs rdiff -u -r1.43 -r1.44 \
    src/sys/compat/linux32/arch/amd64/linux32_machdep.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.