nhi: Fix a race with interrupt teardown during detachHEADmain

When nhi fails to attach on one of my systems (X1 Carbon 6th gen), an
interrupt races with the teardown code such that the rings have been
freed by nhi_detach() before an interrupt triggers.  At the time of
the crash, the thread invoking nhi_attach() is blocked in
bus_teardown_intr() from nhi_pci_free() waiting for the interrupt
thread to finish executing the handler.

To fix, don't just disable the interrupts in nhi_detach(), but
actually tear the handlers down and disable MSI-X before freeing the
rings.

Reviewed by:	obiwac
Differential Revision:	https://reviews.freebsd.org/D53201

0 files changed, 0 insertions, 0 deletions