On Thu, Jan 06, 2011 at 10:51:57AM -0800, Roland Dreier wrote: > > There is another way, which I hope can fix this issue (it fixes > > the graphics drivers). Basically making the Xen MMU be aware of the E820 > > and consider any access to PFNs that are not in RAM to have VM_IO > implicitly set. > > > > The patches are at > git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git > > > > stable/p2m-identity.v4.3 > > > > And posted on LKML )https://lkml.org/lkml/2010/12/30/163) > > > > They _should_ take care of your problem as long as the PFNs you > > are mapping fall within the PCI BAR regions (which I would presume they > > do since you are using ioremap). > > Yes, that should work fine for all the cases I know of in the RDMA > drivers. We are just mapping some PCI BAR space into userspace for > direct access to hardware (just like graphics, I think).
Allright, then it will work. I've respun another version that fundamentally does the same thing but accounts for "what PFN is non-RAM" in a much cleaner way. It is @: git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git devel/p2m-identity.v4.5 will post it soon on LKML. Jack, Vivien: i you do merge it in your tree for testing with Xen and it works properly can I attach your 'Tested-by' on the patch-set? > > I definitely prefer a solution that doesn't require driver authors to > add a Xen-specific fix that isn't required on any other architecture. Heh. You and me are on the same wavelength here. -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html