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Message-ID: <2226c252d2dfa7973bcc298d5bf9521d1e3c5827.camel@kernel.crashing.org>
Subject: Re: [BISECTED REGRESSION] b43legacy broken on G4 PowerBook
From:   Benjamin Herrenschmidt <benh@kernel.crashing.org>
To:     Christoph Hellwig <hch@lst.de>
Cc:     Larry Finger <Larry.Finger@lwfinger.net>,
        Aaro Koskinen <aaro.koskinen@iki.fi>,
        Christian Zigotzky <chzigotzky@xenosoft.de>,
        Michael Ellerman <mpe@ellerman.id.au>,
        linuxppc-dev@lists.ozlabs.org, linux-wireless@vger.kernel.org,
        linux-kernel@vger.kernel.org
Date:   Tue, 11 Jun 2019 19:04:09 +1000
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On Tue, 2019-06-11 at 09:54 +0200, Christoph Hellwig wrote:
> On Tue, Jun 11, 2019 at 04:59:54PM +1000, Benjamin Herrenschmidt
> wrote:
> > Ah stupid me ... it's dma_set_mask that failed, since it has no
> > idea
> > that the calling driver is limited to lowmem.
> > 
> > That's also why the "wrong" patch worked.
> > 
> > So yes, a ZONE_DMA at 30-bits will work, though it's somewhat
> > overkill.
> 
> Well, according to Larry it doesn't actually work, which is odd.

Oh I assume that's just a glitch in the patch :-)

Cheers,
Ben.