Hi Christoph,

On 29/06/22 18:21, Christoph Hellwig wrote:

On Wed, Jun 29, 2022 at 11:09:00AM +1200, Michael Schmitz wrote:

quoted

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