On Wed, Nov 18, 2009 at 06:25:14PM +0900, Tejun Heo wrote: > Hello, > > 10/29/2009 06:22 AM, John Blackwood wrote: > >> Thanks Tejun. percpu_to_phys() makes sense to me also. John, would you > >> like to post a patch for this. > > > > Hi Vivek, > > > > I'm probably not really NUMA/vm savy enough to attempt a patch > > for approval at LKML. > > > > But maybe someone else more qualified can take up the cause. > > Is this still necessary for the current upstream where lpage allocator > is gone (but vmalloc mapping is still there)? > Hi Tejun, I did load a kdump kernel on 32-rc7 and it worked fine. But I guess in this case memory might have come from linearly mapped region. If the default per cpu allocator can get memory from vmalloc region also, then I think we will need this function which can map virtual address to physical address. Are there multiple allocators now? If yes, what are the command line options and I can try to use some other allocator and see if I can force the condition where memory comes from vmalloc region and I observe the crash. Once I can reproduce it, I can also send you the fix you suggested. Thanks Vivek
