Hi Linus, On 22 Sep 2014, at 16:18, Linus Torvalds <torva...@linux-foundation.org> wrote: > On Sun, Sep 21, 2014 at 5:53 PM, Anton Altaparmakov <ai...@cam.ac.uk> wrote: >> >> This patch fixes this issue by type casting "index" to sector_t before >> doing the left shift. > > Ugh. Does the simpler patch to just pass in "block" work as well?
That doesn't work because nothing rounds down "block" to the first block in the page and init_page_buffers() requires "block" to be the first block in the page. The shift right followed by shift left achieves the "rounding down" required. You could do "block & ~(sector_t)(size - 1)" instead of "(sector_t)index << sizebits" if you prefer but not sure that is an improvement! Best regards, Anton > Linus > <patch.diff> -- Anton Altaparmakov <aia21 at cam.ac.uk> (replace at with @) University of Cambridge Information Services, Roger Needham Building 7 JJ Thomson Avenue, Cambridge, CB3 0RB, UK -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/