On Jan 13 Benjamin Herrenschmidt wrote at linux-arch: > On Wed, 2011-01-12 at 16:07 -0800, Andrew Morton wrote: > > drivers/firewire/ohci.c now needs PAGE_KERNEL_RO, but many > > architectures don't implement it. Broke my sparc64 build. > > Some architectures actually cannot implement it even... at least some > variants of powerpc MMUs don't have a combination of protection bits > that allow a kernel-only RO mapping (yeah odd). The simplest perceivable fix, to disable firewire-ohci on architectures which don't have PAGE_KERNEL_RO, would be bad since there are actually sparc64 machines with these controllers. As far as I can tell, the new RO mapping in firewire-ohci can as well be an r/w mapping. We just never need to write at these virtual addresses. So, should we just change the driver to map it r/w when we can't have PAGE_KERNEL_RO, or for simplicity on all architectures? -- Stefan Richter -=====-==-== ---= -==-= http://arcgraph.de/sr/ -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
