On Fri, Sep 21, 2018 at 11:56:08AM +1000, Dave Chinner wrote: > > 3) If slab can't guarantee to return 512-aligned buffer, how to fix > > this data corruption issue? > > I think that the block layer needs to check the alignment of memory > buffers passed to it and take appropriate action rather than > corrupting random memory and returning a sucess status to the bad > bio. Or just reject the I/O. But yes, we already have the queue_dma_alignment helper in the block layer, we just don't do it in the fast path. I think generic_make_request_checks needs to check it, and print an error and return a warning if the alignment requirement isn't met.