On Fri, Sep 21, 2018 at 09:08:05AM +0200, Christoph Hellwig wrote: > 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. That can be done in generic_make_request_checks(), but some cost may be introduced, because each bvec needs to be checked in the fast path. Thanks, Ming
