Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 12 Jul 2016 16:36:17 -0400
From:      Tycho Nightingale <tycho.nightingale@pluribusnetworks.com>
To:        Andriy Gapon <avg@FreeBSD.org>
Cc:        "freebsd-virtualization@freebsd.org" <freebsd-virtualization@FreeBSD.org>
Subject:   Re: bhyve: disable msi and msix on virtio reset?
Message-ID:  <7D5D0A30-1ABA-49F6-83CC-6F398FC25B05@pluribusnetworks.com>
In-Reply-To: <011771a3-8424-7810-d9db-870ddcea2448@FreeBSD.org>
References:  <011771a3-8424-7810-d9db-870ddcea2448@FreeBSD.org>

next in thread | previous in thread | raw e-mail | index | archive | help

Hi,

Yes, writing 0 to the status resister should reset the device including =
all PCIE state.  This implies that vi_reset_dev() needs to take the =
proper actions to bring the associated pci_devinst (which from the =
guest=92s perspective isn=92t a discrete element) back to it=92s reset =
state too.

Tycho

On Jul 12, 2016, at 8:27 AM, Andriy Gapon <avg@FreeBSD.org> wrote:

>=20
> A write of a zero to VTCFG_R_STATUS initiates a virtio device reset =
via
> vc_reset.  Typically this means a call to vi_reset_dev() which resets =
a
> bunch of fields in virtio_softc, but does not touch a corresponding
> pci_devinst (hanging off vs_pi) at all.  Among other things this means
> that PCI MSI and MSI-X states remain unchanged.  One of the =
consequences
> is that we keep using virtio_config_size of 24 if MSI-X is enabled.
>=20
> Should the virtio status reset also reset the PCI state?
>=20
> One practical problem that I see is with illumos fast reboot where the
> illumos virtio driver assumes that the status reset is sufficient to
> return a device to a state like after a clean (full) reboot.
>=20
> Thank you.
> --=20
> Andriy Gapon
> _______________________________________________
> freebsd-virtualization@freebsd.org mailing list
> https://lists.freebsd.org/mailman/listinfo/freebsd-virtualization
> To unsubscribe, send any mail to =
"freebsd-virtualization-unsubscribe@freebsd.org"




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?7D5D0A30-1ABA-49F6-83CC-6F398FC25B05>