Module Name: src
Committed By: maxv
Date: Tue Jun 19 07:23:45 UTC 2018
Modified Files:
src/sys/arch/x86/x86: vm_machdep.c
Log Message:
Explicitly clear l2's pcb_fpcpu when forking.
A context switch (preemption) could occur between
fpusave_lwp(l1, true);
and
memcpy(pcb2, pcb1, sizeof(struct pcb));
In this case, l1's FPU state is re-installed on the current CPU, and
pcb1->pcb_fpcpu becomes non NULL. While it's fine to have l1's state
installed, we don't want to indicate l2's state is installed too.
With lazy fpu this was not a problem, because the context-switch would
not re-install the state, so pcb1->pcb_fpcpu was NULL.
Should fix PR/53383.
To generate a diff of this commit:
cvs rdiff -u -r1.33 -r1.34 src/sys/arch/x86/x86/vm_machdep.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
