Re: git: 0e1f5ab7db2c - main - virtio_mmio: Support command-line parameters

From: Colin Percival <cperciva_at_freebsd.org>
Date: Tue, 18 Oct 2022 17:43:00 UTC
Hi Jessica,

On 10/18/22 08:12, Jessica Clarke wrote:
> On 18 Oct 2022, at 07:03, Colin Percival <cperciva@FreeBSD.org> wrote:
>> --- a/sys/conf/files
>> +++ b/sys/conf/files
>> @@ -3437,6 +3437,7 @@ dev/virtio/pci/virtio_pci_legacy.c	optional	virtio_pci
>> dev/virtio/pci/virtio_pci_modern.c	optional	virtio_pci
>> dev/virtio/mmio/virtio_mmio.c		optional	virtio_mmio
>> dev/virtio/mmio/virtio_mmio_acpi.c	optional	virtio_mmio acpi
>> +dev/virtio/mmio/virtio_mmio_cmdline.c	optional	virtio_mmio
> 
> As I said in the review, this definitely doesn’t work for INTRNG due to
> IRQ number virtualisation, among other things, yet this enables it for
> all architectures, and I believe it should also get its own config
> option as it’s rather dangerous to use (Linux separates it out from
> virtio_mmio and has it off-by-default).

Sorry, I didn't get around to following up with you about this.  Would
moving this into files.x86 satisfy your concerns?  That way it shouldn't
run into issues with other platforms (and would also be turned off by
default, since virtio_mmio isn't in x86 GENERIC kernels).

-- 
Colin Percival
Security Officer Emeritus, FreeBSD | The power to serve
Founder, Tarsnap | www.tarsnap.com | Online backups for the truly paranoid