Andi Kleen wrote: [Tue Feb 13 2007, 01:18:45PM EST] > > > I wasn't suggesting having NULL pointers for pgdats, if that's what you > > mean. > > That is what started the original thread at least. Can happen on some > ia64 platforms. I don't believe there is a NULL pgdat. The code for memory less nodes in ia64 discontig.c allocates the memory less nodes pgdat from the best memory node candidate. If there is a NULL pgdat, then it's a bug. Instead for memory less nodes you don't have any present pages.
I thought the bug was because the process wanted to bind on just one memoryless node and MPOL_BIND didn't handle that correctly and return an error to the process. bob > > > Just nodes with no memory in them, the pgdat would still be there. > > pgdat = struct node, except everything's badly named. > > Ok those can happen even on x86-64, mostly because it's possible > to fill up a node early during boot up with bootmem and then > it's effectively empty. > > [there is even still a open bug when this happens on node 0] > > Handling out of memory here of course has to be always done. > > Just NULL pointers in core data structures are evil. But I'm glad we > agree here. > > Now if it's better to set up a empty node or use a nearby node > for a memory less cpu can be further discussed. I still think > I lean towards the later. > > -Andi > - > 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/ - 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/