netdev - Re: [PATCH net-next v10 2/4] ethtool: provide customized dim profile management

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <1714442379.4695537-1-hengqi@linux.alibaba.com>
Date: Tue, 30 Apr 2024 09:59:39 +0800
From: Heng Qi <hengqi@...ux.alibaba.com>
To: Jakub Kicinski <kuba@...nel.org>
Cc: netdev@...r.kernel.org,
 virtualization@...ts.linux.dev,
 "David S .  Miller" <davem@...emloft.net>,
 Paolo Abeni <pabeni@...hat.com>,
 Eric  Dumazet <edumazet@...gle.com>,
 Jason Wang <jasowang@...hat.com>,
 "Michael S  . Tsirkin" <mst@...hat.com>,
 Brett Creeley <bcreeley@....com>,
 Ratheesh  Kannoth <rkannoth@...vell.com>,
 Alexander Lobakin <aleksander.lobakin@...el.com>,
 Xuan Zhuo <xuanzhuo@...ux.alibaba.com>,
 Tal  Gilboa <talgi@...dia.com>,
 Jonathan Corbet <corbet@....net>,
 linux-doc@...r.kernel.org,
 Maxime Chevallier <maxime.chevallier@...tlin.com>,
 Jiri Pirko <jiri@...nulli.us>,
 Paul  Greenwalt <paul.greenwalt@...el.com>,
 Ahmed Zaki <ahmed.zaki@...el.com>,
 Vladimir Oltean <vladimir.oltean@....com>,
 Kory Maincent <kory.maincent@...tlin.com>,
 Andrew Lunn <andrew@...n.ch>,
 "justinstitt @  google . com" <justinstitt@...gle.com>
Subject: Re: [PATCH net-next v10 2/4] ethtool: provide customized dim profile management

On Mon, 29 Apr 2024 10:47:41 -0700, Jakub Kicinski <kuba@...nel.org> wrote:
> On Sun, 28 Apr 2024 22:49:09 +0800 Heng Qi wrote:
> > >> +	nla_for_each_nested_type(nest, ETHTOOL_A_PROFILE_IRQ_MODERATION, nests, rem) {
> > >> +		ret = nla_parse_nested(moder,
> > >> +				       ARRAY_SIZE(coalesce_irq_moderation_policy) - 1,
> > >> +				       nest, coalesce_irq_moderation_policy,
> > >> +				       extack);
> > >> +		if (ret)
> > >> +			return ret;
> > >> +
> > >> +		if (!NL_REQ_ATTR_CHECK(extack, nest, moder, ETHTOOL_A_IRQ_MODERATION_USEC)) {
> > >> +			if (irq_moder->coal_flags & DIM_COALESCE_USEC)  
> > > There are 3 options here, not 2:
> > >
> > > 	if (irq_moder->coal_flags & flag) {
> > > 		if (NL_REQ_ATTR_CHECK())
> > > 			val = nla_get_u32(...);
> > > 		else
> > > 			return -EINVAL;
> > > 	} else {
> > > 		if (moder[attr_type)) {
> > > 			BAD_ATTR()
> > > 			return -EOPNOTSUPP;
> > > 		}
> > > 	}  
> > 
> > Maybe we missed something.
> > 
> > As shown in the commit log, the user is allowed to modify only
> > a certain fields in irq-moderation. It is assumed that the driver
> > supports modification of usec and pkts, but the user may only
> > modify usec and only fill in the usec attr.
> > 
> > Therefore, the kernel only gets usec attr here. Of course, the user
> > may have passed in 5 groups of "n, n, n", which means that nothing
> > is modified, and rx_profile and irq_moderation attrs are all empty.
> 
> What you describe sounds good, but it's not what the code seems to be
> doing. NL_REQ_ATTR_CHECK() will set an error attribute if the attr is
> not present.

So here we can use:

+ if (moder[ETHTOOL_A_IRQ_MODERATION_USEC]) {
+ 	if (irq_moder->coal_flags & DIM_COALESCE_USEC)
+ 		new_profile[i].usec =
+ 			nla_get_u32(moder[ETHTOOL_A_IRQ_MODERATION_USEC]);
+ 	else
+ 		return -EOPNOTSUPP;
+ }

instead of:

+ if (!NL_REQ_ATTR_CHECK(extack, nest, moder, ETHTOOL_A_IRQ_MODERATION_USEC)) {
+ 	if (irq_moder->coal_flags & DIM_COALESCE_USEC)
+ 		new_profile[i].usec =
+ 			nla_get_u32(moder[ETHTOOL_A_IRQ_MODERATION_USEC]);
+ 	else
+ 		return -EOPNOTSUPP;
+ }

to avoid missing information set in extack?

Thanks.