[PATCH v2 3/3] arch/*/: remove CONFIG_VIRT_TO_BUS

Michael Schmitz schmitzmic at gmail.com
Fri Jul 1 05:21:53 AEST 2022


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




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