Re: [PATCH v3 15/15] Drivers: hv: Add modules to expose /dev/mshv to VMMs running on Hyper-V

Wei Liu
2023-09-23T20:58:51Z

Greg, thank you for looking at the code.

On Sat, Sep 23, 2023 at 09:56:13AM +0200, Greg KH wrote:
> On Fri, Sep 22, 2023 at 11:38:35AM -0700, Nuno Das Neves wrote:
> > +static int __init mshv_vtl_init(void)
> > +{
> > + int ret;
> > +
> > + tasklet_init(&msg_dpc, mshv_vtl_sint_on_msg_dpc, 0);
> > + init_waitqueue_head(&fd_wait_queue);
> > +
> > + if (mshv_vtl_get_vsm_regs()) {
> > + pr_emerg("%s: Unable to get VSM capabilities !!\n", __func__);
> > + BUG();
> > + }
>
>
> So you crash the whole kernel if someone loads this module on a non-mshv
> system?
>
> That seems quite excessive and hostile :(
>

I agree this can be more lenient. It should be safe to just return an
error code (ENODEV) and let user space decide the next action.

Saurabh, let me know what you think.

Thanks,
Wei.

> Or am I somehow reading this incorrectly?
>
> thanks,
>
> greg k-h
>