[PATCH net 0/3] ionic: fix port_info lifetime problems around device reset

The ionic port_info DMA buffer is read by most of the driver's ethtool
ops, and is freed and reallocated by the firmware recovery and PCI reset
paths. Those paths hold no lock that the ethtool ops honor - the
driver takes no rtnl anywhere - so ethtool can dereference a pointer
that has just been set to NULL, or read out of a buffer that has just
been freed.

Patch 1 adds the missing NULL checks to the six ethtool ops that lacked
them; ionic_get_link_ext_stats() and ionic_get_link_ksettings() already
had them. It fixes the oops reachable today and does not depend on the
other two, so it stands on its own if the approach in patch 2 needs
more discussion.

Patch 2 detaches the netdev in ionic_reset_prepare(). The ethtool core
only stays out of a driver when netif_device_present() is false, and the
firmware recovery path already relies on that; the PCI reset path never
did. This is what actually closes the window rather than papering over
it.

Patch 3 fixes an unrelated leak of the same buffer that turned up while
auditing the free paths: probe failures after the port has been set up
unwind through a label that never calls ionic_port_reset().

The port_info lifetime problems were pointed out by the netdev AI review
bot on an unrelated ionic ethtool patch:
https://netdev-ai.bots.linux.dev/sashiko/#/patchset/20260731214021.15279-1-eric.joyner@amd.com

Signed-off-by: Eric Joyner <redacted>
---
Eric Joyner (3):
      ionic: check for a NULL port_info in the remaining ethtool ops
      ionic: detach the netdev in the PCI reset handler
      ionic: free port_info when probe fails after the port is set up

 .../net/ethernet/pensando/ionic/ionic_bus_pci.c    |  2 ++
 .../net/ethernet/pensando/ionic/ionic_ethtool.c    | 30 ++++++++++++++++++++++
 2 files changed, 32 insertions(+)
---
base-commit: 24ef02f934eeb48830cff6b739abc3c62b1d107b
change-id: 20260814-ionic-port-info-lifetime-3163779cb298

Best regards,
-- 
Eric Joyner [off-list ref]