On Wed, Apr 17, 2013 at 8:11 PM, Thomas Lange <thomas@xxxxxxxxxxxx> wrote: > commit c17a6554 unintentionally(?) modified the PAGE_MASK type > from (int) to (long unsigned int). > > This breaks ioremap (and possibly more) when using 64BIT_PHYS_ADDR on > 32 bit systems. > Example of failing code from ioremap.c: > > phys_addr &= PAGE_MASK; > > Since phys_addr is 64 bit (unsigned long long) when 64BIT_PHYS_ADDR and > PAGE_MASK is 32bit (long unsigned int), the upper 32 bits will always > be zeroed which is not what we want/expect. > > The code above works if PAGE_MASK is a _signed_ 32bit int though. > > Some possible fixes: > > A) Simply revert the commit. Makes ioremap work again, but then PAGE_MASK > is a signed int. Do we really want a mask that is 'signed'? Already fixed, cfr. https://lkml.org/lkml/2013/4/22/518 Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds
