[lkml]   [2019]   [Feb]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH v3 0/8] nic: thunderx: fix communication races between VF & PF
From: Vadim Lomovtsev <>
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.

 \ /
  Last update: 2019-02-22 20:45    [W:0.416 / U:0.040 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site