On 11/6/20 6:00 AM, Jason Gunthorpe wrote:
> This moves siw and rxe to be virtual devices in the device tree:
>
> lrwxrwxrwx 1 root root 0 Nov 6 13:55 /sys/class/infiniband/rxe0 -> ../../devices/virtual/infiniband/rxe0/
>
> Previously they were trying to parent themselves to the physical device of
> their attached netdev, which doesn't make alot of sense.
>
> My hope is this will solve some weird syzkaller hits related to sysfs as
> it could be possible that the parent of a netdev is another netdev, eg
> under bonding or some other syzkaller found netdev configuration.
>
> Nesting a ib_device under anything but a physical device is going to cause
> inconsistencies in sysfs during destructions.
Hi Jason,
I do not know enough about the code touched by this patch to comment on
the patch itself. But I expect that the blktests code will have to be
modified to compensate for this change. How to translate the name of a
virtual RDMA device into a netdev device with this patch applied?
>From the blktests project:
# Check whether or not an rdma_rxe instance has been associated with
# network interface $1.
has_rdma_rxe() {
local f
for f in /sys/class/infiniband/*/parent; do
if [ -e "$f" ] && [ "$(<"$f")" = "$1" ]; then
return 0
fi
done
return 1
}
rdma_dev_to_net_dev() {
local b d rdma_dev=$1
b=/sys/class/infiniband/$rdma_dev/parent
if [ -e "$b" ]; then
echo "$(<"$b")"
else
echo "${rdma_dev%_siw}"
fi
}
Bart.
