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Date:   Sun, 30 Oct 2022 08:45:14 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Al Viro <viro@zeniv.linux.org.uk>
Cc:     Christoph Hellwig <hch@lst.de>, linux-block@vger.kernel.org
Subject: Re: [bug?] blk_queue_may_bounce() has the comparison max_low_pfn
 and max_pfn wrong way
Message-ID: <20221030074514.GA4214@lst.de>
References: <Y1wZTtENDq3fvs6n@ZenIV>
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On Fri, Oct 28, 2022 at 07:02:54PM +0100, Al Viro wrote:
> Now, the last term in expression in blk_queue_may_bounce() is
> true only on the boxen where max_pfn is no greater than max_low_pfn.
> 
> Unless I'm very confused, that's the boxen where we don't *have*
> any highmem pages.

Yes, this go mixed up.