From: Vadim Lomovtsev <vlomovt...@marvell.com> Date: Wed, 20 Feb 2019 11:02:42 +0000
> The ThunderX CN88XX NIC Virtual Function driver uses mailbox interface > to communicate to physical function driver. Each of VF has it's own pair > of mailbox registers to read from and write to. The mailbox registers > has no protection from possible races, so it has to be implemented > at software side. > > After long term testing by loop of 'ip link set <ifname> up/down' > command it was found that there are two possible scenarios when > race condition appears: > 1. VF receives link change message from PF and VF send RX mode > configuration message to PF in the same time from separate thread. > 2. PF receives RX mode configuration from VF and in the same time, > in separate thread PF detects link status change and sends appropriate > message to particular VF. > > Both cases leads to mailbox data to be rewritten, NIC VF messaging control > data to be updated incorrectly and communication sequence gets broken. > > This patch series is to address race condition with VF & PF communication. > > Changes: > v1 -> v2 > - 0000: correct typo in cover letter subject: 'betwen' -> 'between'; > - move link state polling request task from pf to vf > instead of cheking status of mailbox irq; > v2 -> v3 > - 0003: change return type of nicvf_send_cfg_done() function > from int to void; > - 0007: update subject and remove unused variable 'netdev' > from nicvf_link_status_check_task() function; Series applied, thanks.
