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Date:   Fri, 1 Jul 2022 07:21:53 +1200
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Subject: Re: [PATCH v2 3/3] arch/*/: remove CONFIG_VIRT_TO_BUS
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To:     Christoph Hellwig <hch@infradead.org>
Cc:     Arnd Bergmann <arnd@kernel.org>,
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From:   Michael Schmitz <schmitzmic@gmail.com>
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Hi Christoph,

On 29/06/22 18:21, Christoph Hellwig wrote:
> On Wed, Jun 29, 2022 at 11:09:00AM +1200, Michael Schmitz wrote:
>> And all SCSI buffers are allocated using kmalloc? No way at all for user
>> space to pass unaligned data?
> Most that you will see actually comes from the page allocator.  But
> the block layer has a dma_alignment limit, and when userspace sends
> I/O that is not properly aligned it will be bounce buffered before
> it it sent to the driver.

That limit is set to L1_CACHE_BYTES on m68k so we're good here.

Thanks,

     Michael