git: 0b39d72d0491 - main - virtio: use modern mode for transitional device by default

The branch main has been updated by tuexen:

URL: https://cgit.FreeBSD.org/src/commit/?id=0b39d72d0491c77e3e9883015b1fac46663c71de

commit 0b39d72d0491c77e3e9883015b1fac46663c71de
Author:     Timo Völker <timo.voelker@fh-muenster.de>
AuthorDate: 2026-04-04 14:49:54 +0000
Commit:     Michael Tuexen <tuexen@FreeBSD.org>
CommitDate: 2026-04-04 14:49:54 +0000

    virtio: use modern mode for transitional device by default
    
    This patch changes the default value of the loader tunable
    hw.virtio.pci.transitional to 1. This means, virtio uses the
    modern mode for transitional devices by default.
    
    The return values of vtpci_modern_probe() and vtpci_legacy_probei()
    were chosen to prefer modern mode, but hw.virtio.pci.transitional=0
    prevents modern mode.
    Setting hw.virtio.pci.transitional to 1 by default seems a better fit.
    
    Reviewed by:            tuexen
    Differential Revision:  https://reviews.freebsd.org/D55894
---
 share/man/man4/virtio.4                | 2 +-
 sys/dev/virtio/pci/virtio_pci_modern.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/share/man/man4/virtio.4 b/share/man/man4/virtio.4
index 8252cc1b7954..6af6300b1cee 100644
--- a/share/man/man4/virtio.4
+++ b/share/man/man4/virtio.4
@@ -114,7 +114,7 @@ use the legacy
 .Nm
 driver
 .Pq 0 .
-The default value is 0.
+The default value is 1.
 .El
 .Sh SEE ALSO
 .Xr virtio_balloon 4 ,
diff --git a/sys/dev/virtio/pci/virtio_pci_modern.c b/sys/dev/virtio/pci/virtio_pci_modern.c
index 108fd2b5f8e9..baf7c448bb95 100644
--- a/sys/dev/virtio/pci/virtio_pci_modern.c
+++ b/sys/dev/virtio/pci/virtio_pci_modern.c
@@ -191,7 +191,7 @@ static void	vtpci_modern_write_device_8(struct vtpci_modern_softc *,
 /* Tunables. */
 SYSCTL_DECL(_hw_virtio_pci);
 
-static int vtpci_modern_transitional = 0;
+static int vtpci_modern_transitional = 1;
 SYSCTL_INT(_hw_virtio_pci, OID_AUTO, transitional, CTLFLAG_RDTUN,
     &vtpci_modern_transitional, 0,
     "If 0, a transitional VirtIO device is used in legacy mode; otherwise, in modern mode.");