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Date: Thu, 24 May 2018 18:44:22 +0200
From: Andrew Lunn <andrew@lunn.ch>
To: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Cc: Vladimir Zapolskiy <vz@mleia.com>,
        Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>,
        "David S. Miller" <davem@davemloft.net>, netdev@vger.kernel.org,
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Subject: Re: [PATCH 1/6] ravb: remove custom .nway_reset from ethtool ops
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On Thu, May 24, 2018 at 07:18:28PM +0300, Sergei Shtylyov wrote:
> Hello!
> 
> On 05/24/2018 05:11 PM, Vladimir Zapolskiy wrote:
> 
> >>> The change fixes a sleep in atomic context issue, which can be
> >>> always triggered by running 'ethtool -r' command, because
> >>> phy_start_aneg() protects phydev fields by a mutex.
> 
>   You don't say that *not* grabbing the spinlock is safe... 

For it to be unsafe, i think that would mean phylib would need to call
back into the MAC driver? The only way that could happen is via the
adjust_link call. And that will deadlock, since it takes the same
lock.

Or am i/we missing something?

	    Andrew