On Mon, Jul 25, 2005 at 03:10:33PM -0700, Andrew Morton wrote: > Vivek Goyal <[EMAIL PROTECTED]> wrote: > > > > > If you don't stop the DMA engines before you boot the new kernel, the > > > addresses they have to send data to will now be random points in that > > > kernel's memory, leading to potential corruption of the new kernel > > > image. > > > > [Copying it to fastboot and linux-kernel mailing lists] > > > > We are booting second kernel (capture kernel) from a reserved memory > > location > > to take care of on-going DMA issues. So even if some DMA transactions are > > going > > on after the crash they will not corrupt the new kernel. > > > > > > > > The interrupt panic of the fusion is probably a symptom of this: I bet a > > > DMA transfer has just completed and the interrupt is to inform us of > > > this (however, in the new kernel we're not expecting any transfers). > > > > That might very well be the case. So driver should simply ignore the > > interrupt > > when it is not expecting it or it should reset the device if it finds that > > some interrupts are pending when it should not have been there. > > > > Basically it is a matter of hardening the driver so that it can handle/ > > initialize the device even if the device is not in reset state. > > I'd expect that a lot of these problems could be reduced by simply pausing > for a while in the crash handler, wait for I/O to complete. >
Andrew, We will test it out and see if it helps on some of the already reported issues. Thanks Vivek - 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/