netdev - Re: [PATCH net-next v13 02/13] net: pse-pd: Add support for reporting events

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: <20250616141012.31305f81@kmaincent-XPS-13-7390>
Date: Mon, 16 Jun 2025 14:10:12 +0200
From: Kory Maincent <kory.maincent@...tlin.com>
To: Jakub Kicinski <kuba@...nel.org>
Cc: Andrew Lunn <andrew@...n.ch>, Oleksij Rempel <o.rempel@...gutronix.de>,
 "David S. Miller" <davem@...emloft.net>, Eric Dumazet
 <edumazet@...gle.com>, Paolo Abeni <pabeni@...hat.com>, Jonathan Corbet
 <corbet@....net>, Donald Hunter <donald.hunter@...il.com>, Rob Herring
 <robh@...nel.org>, Andrew Lunn <andrew+netdev@...n.ch>, Simon Horman
 <horms@...nel.org>, Heiner Kallweit <hkallweit1@...il.com>, Russell King
 <linux@...linux.org.uk>, Krzysztof Kozlowski <krzk+dt@...nel.org>, Conor
 Dooley <conor+dt@...nel.org>, Liam Girdwood <lgirdwood@...il.com>, Mark
 Brown <broonie@...nel.org>, Thomas Petazzoni
 <thomas.petazzoni@...tlin.com>, netdev@...r.kernel.org,
 linux-doc@...r.kernel.org, Kyle Swenson <kyle.swenson@....tech>, Dent
 Project <dentproject@...uxfoundation.org>, kernel@...gutronix.de, Maxime
 Chevallier <maxime.chevallier@...tlin.com>, devicetree@...r.kernel.org,
 linux-kernel@...r.kernel.org
Subject: Re: [PATCH net-next v13 02/13] net: pse-pd: Add support for
 reporting events

Le Mon, 16 Jun 2025 13:57:22 +0200,
Kory Maincent <kory.maincent@...tlin.com> a écrit :

> Le Sat, 14 Jun 2025 12:18:43 -0700,
> Jakub Kicinski <kuba@...nel.org> a écrit :
> 
> > On Tue, 10 Jun 2025 10:11:36 +0200 Kory Maincent wrote:  
> > > +static struct net_device *
> > > +pse_control_find_net_by_id(struct pse_controller_dev *pcdev, int id,
> > > +			   netdevice_tracker *tracker)
> > > +{
> > > +	struct pse_control *psec, *next;
> > > +
> > > +	mutex_lock(&pse_list_mutex);
> > > +	list_for_each_entry_safe(psec, next, &pcdev->pse_control_head,
> > > list) {    
> > 
> > nit: _safe is not necessary here, the body of the if always exits after
> > dropping the lock  
> 
> Indeed, I will drop it.
> 
> > Do you plan to add more callers for this function?
> > Maybe it's better if it returns the psec pointer with the refcount
> > elevated. Because it would be pretty neat if we could move the 
> > ethnl_pse_send_ntf(netdev, notifs, &extack); that  pse_isr() does
> > right after calling this function under the rtnl_lock.
> > I don't think calling ethnl_pse_send_ntf() may crash the kernel as is,
> > but it feels like a little bit of a trap to have ethtool code called
> > outside of any networking lock.  
> 
> Ok. My aim was to put the less amount of code inside the rtnl lock but if you
> prefer I will call ethnl_pse_send_ntf() with the lock acquired.

psec pointer is private to pse so we will have something like the following.
Is it ok for you ?

psec = pse_control_find_by_id(pcdev, i, &tracker);
rtnl_lock();
if (psec && psec->attached_phydev &&
    psec->attached_phydev->attached_dev)
	ethnl_pse_send_ntf(psec->attached_phydev->attached_dev, notifs,
			   &extack);
rtnl_unlock();
pse_control_put(psec);

-- 
Köry Maincent, Bootlin
Embedded Linux and kernel engineering
https://bootlin.com