linux-kernel - Re: stmmac ethernet in kernel 4.9-rc6: coalescing related pauses.

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: <9a85da24-85cf-f94e-908f-a10eecac2369@gmx.de>
Date:   Mon, 5 Dec 2016 23:37:09 +0100
From:   Lino Sanfilippo <LinoSanfilippo@....de>
To:     Pavel Machek <pavel@....cz>
Cc:     Giuseppe CAVALLARO <peppe.cavallaro@...com>,
        alexandre.torgue@...com, David Miller <davem@...emloft.net>,
        netdev@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: stmmac ethernet in kernel 4.9-rc6: coalescing related pauses.

Hi Pavel,

On 05.12.2016 23:02, Pavel Machek wrote:
> 
> we need spin_lock_bh at minimum, as we are locking user context
> against timer.
> 
> Best regards,
> 									Pavel
> 

I was referring to stmmac_tx_clean() which AFAICS is only called from softirq context,
(one time in the timer handler and one time in napi poll handler) so a spin_lock() should
be sufficient. I cant see how this is called from userspace. If it were, a spin_lock_bh() had
to be used, of course.

Regards,
Lino