On Tue, Jun 28, 2022 at 04:30:10PM +0200, Christian Marangi wrote:
commit 386228c694bf1e7a7688e44412cb33500b0ac585 upstream.
It was discovered that the Documentation lacks of a fundamental detail on how to correctly change the MAX_FRAME_SIZE of the switch.
In fact if the MAX_FRAME_SIZE is changed while the cpu port is on, the switch panics and cease to send any packet. This cause the mgmt ethernet system to not receive any packet (the slow fallback still works) and makes the device not reachable. To recover from this a switch reset is required.
To correctly handle this, turn off the cpu ports before changing the MAX_FRAME_SIZE and turn on again after the value is applied.
Fixes: f58d2598cf70 ("net: dsa: qca8k: implement the port MTU callbacks") Cc: stable@vger.kernel.org Signed-off-by: Christian Marangi ansuelsmth@gmail.com Link: https://lore.kernel.org/r/20220621151122.10220-1-ansuelsmth@gmail.com Signed-off-by: Jakub Kicinski kuba@kernel.org [ backport: fix conflict using the old port_sts struct instead of bitmap ]
drivers/net/dsa/qca8k.c | 23 +++++++++++++++++++++-- 1 file changed, 21 insertions(+), 2 deletions(-)
This only applied to 5.15.y and 5.18.y, what about 5.10.y? Please give us a hint as to what kernel(s) a backport is for when sending them.
thanks,
greg k-h