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Subject: Re: [PATCH net-next 2/6] net: ipa: reorder netdev pointer assignments
To:     Jakub Kicinski <kuba@kernel.org>
Cc:     davem@davemloft.net, bjorn.andersson@linaro.org,
        evgreen@chromium.org, cpratapa@codeaurora.org,
        subashab@codeaurora.org, elder@kernel.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20210804153626.1549001-1-elder@linaro.org>
 <20210804153626.1549001-3-elder@linaro.org>
 <20210805182712.4f071aa8@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
From:   Alex Elder <elder@linaro.org>
Message-ID: <5b2a7fbc-f485-3c6c-af05-d8df18f55406@linaro.org>
Date:   Fri, 6 Aug 2021 06:39:49 -0500
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On 8/5/21 8:27 PM, Jakub Kicinski wrote:
> On Wed,  4 Aug 2021 10:36:22 -0500 Alex Elder wrote:
>> Assign the ipa->modem_netdev and endpoint->netdev pointers *before*
>> registering the network device.  As soon as the device is
>> registered it can be opened, and by that time we'll want those
>> pointers valid.
>>
>> Similarly, don't make those pointers NULL until *after* the modem
>> network device is unregistered in ipa_modem_stop().
>>
>> Signed-off-by: Alex Elder <elder@linaro.org>
> 
> This one seems like a pretty legit race, net would be better if you
> don't mind.

I don't mind at all.  But now that it's accepted, I'm not sure how
to go about getting it back-ported.  Mainly I don't want to interfere
with any interaction between net/master and net-next/master...  Maybe
you're in a better position to do that.  And if so:

Fixes: 57f63faf0562 ("net: ipa: only set endpoint netdev pointer when in 
use")

I'll happily do it if you can tell me the best way how.  Thanks.

					-Alex