From: Tianyu Lan <ltykernel@xxxxxxxxx> Sent: Saturday, October 2, 2021 7:40 AM
>
>
> On 10/2/2021 9:26 PM, Michael Kelley wrote:
> >> @@ -303,10 +365,26 @@ void vmbus_disconnect(void)
> >> vmbus_connection.int_page = NULL;
> >> }
> >>
> >> - hv_free_hyperv_page((unsigned long)vmbus_connection.monitor_pages[0]);
> >> - hv_free_hyperv_page((unsigned long)vmbus_connection.monitor_pages[1]);
> >> - vmbus_connection.monitor_pages[0] = NULL;
> >> - vmbus_connection.monitor_pages[1] = NULL;
> >> + if (hv_is_isolation_supported()) {
> >> + memunmap(vmbus_connection.monitor_pages[0]);
> >> + memunmap(vmbus_connection.monitor_pages[1]);
> > The matching memremap() calls are made in vmbus_connect() only in the
> > SNP case. In the non-SNP case, monitor_pages and monitor_pages_original
> > are the same, so you would be doing an unmap, and then doing the
> > set_memory_encrypted() and hv_free_hyperv_page() using an address
> > that is no longer mapped, which seems wrong. Looking at memunmap(),
> > it might be a no-op in this case, but even if it is, making them conditional
> > on the SNP case might be a safer thing to do, and it would make the code
> > more symmetrical.
> >
>
> Yes, memumap() does nothing is the non-SNP CVM and so I didn't check CVM
> type here. I will add the check in the next version.
>
> Thanks.
>
I would also be OK with just adding a comment to that effect, just so someone
looking at the code in the future understands that there's not a problem.
Your call.
Michael
