Theo Buehler <t...@theobuehler.org> writes:
> On Mon, Mar 28, 2022 at 07:47:45AM +0200, Anton Lindqvist wrote: >> On Sun, Mar 27, 2022 at 06:22:20PM -0600, Dave Voutila wrote: >> > CVSROOT: /cvs >> > Module name: src >> > Changes by: d...@cvs.openbsd.org 2022/03/27 18:22:20 >> > >> > Modified files: >> > sys/arch/amd64/amd64: vmm.c >> > >> > Log message: >> > vmm(4): add quiesce/wakeup hooks to sync vcpu state. >> > >> > If a host suspends or hibernates, a task in the middle of using >> > vcpu state may be rescheduled to another cpu. This is primarily a >> > problem for Intel hosts as vcpu state is kept local to the physical >> > cpu and must be flushed back to physical memory before another cpu >> > can issue certain vmx instructions. >> > >> > This change ensures no tasks are actively using the vmm device, >> > flushes all vcpu state (if Intel hardware), and turns off virtualization >> > mode on the host cpus. Upon wakeup, we reverse the process. >> > >> > Reported on bugs@ by mpi@. OK mlarkin@ >> >> This broke kernel compilation on syzkaller. >> >> sys/arch/amd64/amd64/vmm.c:499:11: error: implicit declaration of function >> 'vmx_remote_vmclear' is invalid in C99 >> [-Werror,-Wimplicit-function-declaration] >> >> https://syzkaller.appspot.com/bug?id=c58155e5ad57153055f3b4db9d86234cd086fe3b > > Just ran into this as well. The below fixes 'make release'. Does this > look right? > I believe this was committed, but yes, this is correct. Thanks for the assist, tb. > Index: arch/amd64/amd64/vmm.c > =================================================================== > RCS file: /cvs/src/sys/arch/amd64/amd64/vmm.c,v > retrieving revision 1.304 > diff -u -p -r1.304 vmm.c > --- arch/amd64/amd64/vmm.c 28 Mar 2022 00:22:20 -0000 1.304 > +++ arch/amd64/amd64/vmm.c 28 Mar 2022 05:52:33 -0000 > @@ -494,6 +494,7 @@ vmm_quiesce_vmx(void) > continue; > } > > +#ifdef MULTIPROCESSOR > if (vcpu->vc_last_pcpu != curcpu()) { > /* Remote cpu vmclear via ipi. */ > err = vmx_remote_vmclear(vcpu->vc_last_pcpu, > @@ -502,7 +503,9 @@ vmm_quiesce_vmx(void) > printf("%s: failed to remote vmclear " > "vcpu %d of vm %d\n", __func__, > vcpu->vc_id, vm->vm_id); > - } else { > + } else > +#endif > + { > /* Local cpu vmclear instruction. */ > if ((err = vmclear(&vcpu->vc_control_pa))) > printf("%s: failed to locally vmclear "
