On Fri, 1 Feb 2008 16:39:07 +0900 "Kenichi Okuyama" <[EMAIL PROTECTED]> wrote:
> Dear all, > > I was looking at the ./mm/rmap.c .. I found that, in function > "page_referenced_one()", > struct mm_struct *mm = vma->vm_mm; > was being refererred without NULL check. > > Though I do agree that this works for most of the cases, I thought it > is better to add > BUG_ON() for case of mm being NULL. > > attached is the patch for this If we dereference NULL then the kernel will display basically the same information as would a BUG, and it takes the same action. So adding a BUG_ON here really doesn't gain us anything. Also, I think vma->vm_mm == 0 is not a valid state, so this just shouldn't happen - the code is OK to assume that a particular invariant is being honoured. -- 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/
