On Mon, Apr 30, 2007 at 10:38:19AM -0700, William Lee Irwin III wrote: >>>> Here's what I did for i386 for someone concerned about blowing the >>>> stack.
On Mon, Apr 30, 2007 at 10:45:10AM -0700, William Lee Irwin III wrote: >>> Add checks to __pa() so it goes BUG() on vmallocspace addresses. On Mon, 30 Apr 2007 20:52:42 +0200 Andi Kleen <[EMAIL PROTECTED]> wrote: >> Sorry I think that's too costly to do. __pa is pretty common On Mon, Apr 30, 2007 at 08:20:59PM +0100, Alan Cox wrote: > But not too costly to do if it is done solely with vmalloc the stack > for > debug purposes. The bigger problem with the vmalloc approach is there > are > still offenders who DMA off the kernel stack on i386 although I'd hope > they are all ancient... we'll find out with this anyway Sorry about the email address switch. This is actually work-related. The stack vmalloc() and __pa() patches were partially intended to catch or otherwise deliberately break such offenders and go BUG() on them. The __pa() check in particular is exclusively for the purpose of catching them. The primary motive being the stack vmalloc() patches remained, of course, establishing a guard page to trap stack overflows. -- wli - 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/
