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

Michael Schmitz
2022-06-30T19:22:09Z

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