* Andrew Morton <[EMAIL PROTECTED]> wrote: > On Wed, 05 Dec 2007 18:15:54 +1100 > [EMAIL PROTECTED] wrote: > > > +static int > > +videobuf_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf) > > { > > struct page *page; > > > > - dprintk(3,"nopage: fault @ %08lx [vma %08lx-%08lx]\n", > > - vaddr,vma->vm_start,vma->vm_end); > > - if (vaddr > vma->vm_end) > > - return NOPAGE_SIGBUS; > > + dprintk(3,"fault: fault @ %08lx [vma %08lx-%08lx]\n", > > + (unsigned long)vmf->virtual_address,vma->vm_start,vma->vm_end); > > page = alloc_page(GFP_USER | __GFP_DMA32); > > if (!page) > > - return NOPAGE_OOM; > > + return VM_FAULT_OOM; > > clear_user_page(page_address(page), vaddr, page); > > This didn't compile on sparc64 because `vaddr' is undefined. > > > Let us see why: > > #define clear_user_page(page, vaddr, pg) clear_page(page) > #define copy_user_page(to, from, vaddr, pg) copy_page(to, from) > > #define __alloc_zeroed_user_highpage(movableflags, vma, vaddr) \ > alloc_page_vma(GFP_HIGHUSER | __GFP_ZERO | movableflags, vma, vaddr) > > root cause: lack of argument checking on x86 due to stupid macros. > > > Could someone *please* start a little project of extirpating this > utter brain damage? Convert those macros to typechecked static > inlines on x86 (at least) so this sort of thing (which happens again > and again and again) is lessened?
i wanted to write a reply to suggest a checkpatch policy for this. When i noticed this sentence at the end of your mail: > macros are such miserable things. I wonder if we could get checkpatch > to help out here? /me too :-) any policy that gets into checkpatch.pl's default output is a policy for arch/x86 patch merging. (as long as it's not a false positive) And because we do all these unifications the effects of checkpatch.pl permeate basically every aspect of arch/x86. one approach would be to make new macros in include/* a no-no. That would hurt a few of the legitimate uses though, so maybe a useful refinement would be to check the structure of macros: are arguments used twice (side-effect), are arguments unused (typechecking dager), are arguments cast (type-loss danger), etc. Looks very hard to implement though :-/ Andy, what do you think? Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/