RE: [PATCH v2,net] hv_netvsc: Fix tx_table init in rndis_set_subchannel()
From: Haiyang Zhang <haiyangz@microsoft.com>
Date: 2019-12-15 16:38:45
Also in:
linux-hyperv, lkml
-----Original Message----- From: Jakub Kicinski <redacted> Sent: Saturday, December 14, 2019 2:30 PM To: Haiyang Zhang <haiyangz@microsoft.com> Cc: sashal@kernel.org; linux-hyperv@vger.kernel.org; netdev@vger.kernel.org; KY Srinivasan [off-list ref]; Stephen Hemminger [off-list ref]; olaf@aepfle.de; vkuznets [off-list ref]; davem@davemloft.net; linux-kernel@vger.kernel.org Subject: Re: [PATCH v2,net] hv_netvsc: Fix tx_table init in rndis_set_subchannel() On Wed, 11 Dec 2019 14:26:27 -0800, Haiyang Zhang wrote:quoted
Host can provide send indirection table messages anytime after RSS is enabled by calling rndis_filter_set_rss_param(). So the host provided table values may be overwritten by the initialization in rndis_set_subchannel(). To prevent this problem, move the tx_table initialization before calling rndis_filter_set_rss_param(). Fixes: a6fb6aa3cfa9 ("hv_netvsc: Set tx_table to equal weight aftersubchannels open")quoted
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>Applied, but there are two more problems with this code: - you should not reset the indirection table if it was configured by the user to something other than the default (use the netif_is_rxfh_configured() helper to check for that)
For Send indirection table (tx_table) ethtool doesn't have the option to set it, and it's usually provided by the host. So we always initialize it... But, yes, for Receive indirection table (rx_table), I will make a fix, so it will be set to default only for new devices, or changing the number of channels; otherwise it will remain the same during operations like changing MTU, ringparam.
- you should use the ethtool_rxfh_indir_default() wrapper
For rx_table, we already use it:
rndis_device->rx_table[i] = ethtool_rxfh_indir_default(
For tx_table, I know it's the same operation (%, mod), but this wrapper
function's name is for rx_table. Should we use it for tx_table too?
Please fix the former problem in the net tree, and after net is merged into linux/master and net-next in a week or two please follow up with the fix for the latter for net-next.
Sure. Thanks, - Haiyang