On Mon, Mar 27, 2017 at 05:47:02PM +0200, Helge Deller wrote: > pa_memcpy() is the major memcpy implementation in the parisc kernel which is > used to do any kind of userspace/kernel memory copies. > > Al Viro noticed various bugs in the implementation of pa_mempcy(), most notably > that in case of faults it may report back to have copied more bytes than it > actually did. > > Fixing those bugs is quite hard in the C-implementation, because the compiler > is messing around with the registers and we are not guaranteed that specific > variables are always in the same processor registers. This makes proper fault > handling complicated. > > This patch implements pa_memcpy() in assembler. That way we have correct fault > handling and adding a 64-bit copy routine was quite easy. Hmm... Is there any point trying to fall back from store fault to byte copy? Note that in copy_dstaligned() dst *is* aligned, so if the word store fails, there's no realistic chance of having a byte store succeed. -- To unsubscribe from this list: send the line "unsubscribe linux-parisc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
