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Date:   Thu, 28 Apr 2022 14:22:17 +0200
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Subject: Re: [PATCH 0/3] can: grcan: Bug fixes
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To:     Marc Kleine-Budde <mkl@pengutronix.de>
Cc:     linux-can@vger.kernel.org, Wolfgang Grandegger <wg@grandegger.com>,
        Oliver Hartkopp <socketcan@hartkopp.net>,
        linux-kernel@vger.kernel.org, software@gaisler.com
References: <20220427134307.22981-1-andreas@gaisler.com>
 <20220428065058.mf76kmhamddsqsvk@pengutronix.de>
From:   Andreas Larsson <andreas@gaisler.com>
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On 2022-04-28 08:50, Marc Kleine-Budde wrote:
> On 27.04.2022 15:43:04, Andreas Larsson wrote:
>> These patches
>> * makes sure that DMA memory is allocated properly
>> * avoids the tx errata workaround needlessly being applied
>> * fixes a bug where the driver can be left hanging without interrupts enabled
>>
>> Andreas Larsson (2):
>>    can: grcan: Fix broken system id check for errata workaround needs
>>    can: grcan: Only use the napi poll budget for rx
>>
>> Daniel Hellstrom (1):
>>    can: grcan: use ofdev->dev when allocating DMA memory
> 
> Thanks for the patches. Can you please add a "Fixes:" tag to each patch.
>  From the description it seems they should be backported to the stable
> kernels, correct?


For patch 1 I can add a Fixes: that points to 53b7670e5735, which is the
patch after which the patch is needed (even though that commit is not
bad in itself, but merely exposes a wrongly used device pointer in the
grcan driver).

For patch 2 though I am not sure. I don't think the problem has always
been there, but I am not really sure what commit to point to. The fix is
at least needed for 4.9 and onward and 4.9 is the oldest stable branch
still under maintenance. Seems not to be worth the effort to find
exactly from which commit the grcan driver's quirky use of the napi
budget actually lead to problems just to make sure that it gets applied
to all currently maintained stable branches. Suggestions?

For patch 3 I can point to the driver's original commit for the grcan
driver as the problem has been there all along.

Cheers,
Andreas