On Tue, Dec 4, 2018 at 5:09 PM Wei Yang <richard.weiyang@xxxxxxxxx> wrote: > > On Tue, Dec 04, 2018 at 04:52:52PM +0800, Pingfan Liu wrote: > >On Tue, Dec 4, 2018 at 4:34 PM Wei Yang <richard.weiyang@xxxxxxxxx> wrote: > >> > >> On Tue, Dec 04, 2018 at 03:20:13PM +0800, Pingfan Liu wrote: > >> >On Tue, Dec 4, 2018 at 2:54 PM Wei Yang <richard.weiyang@xxxxxxxxx> wrote: > >> >> > >> >> On Tue, Dec 04, 2018 at 11:05:57AM +0800, Pingfan Liu wrote: > >> >> >During my test on some AMD machine, with kexec -l nr_cpus=x option, the > >> >> >kernel failed to bootup, because some node's data struct can not be allocated, > >> >> >e.g, on x86, initialized by init_cpu_to_node()->init_memory_less_node(). But > >> >> >device->numa_node info is used as preferred_nid param for > >> >> > >> >> could we fix the preferred_nid before passed to > >> >> __alloc_pages_nodemask()? > >> >> > >> >Yes, we can doit too, but what is the gain? > >> > >> node_zonelist() is used some places. If we are sure where the problem > >> is, it is not necessary to spread to other places. > >> > >> > > >> >> BTW, I don't catch the function call flow to this point. Would you mind > >> >> giving me some hint? > >> >> > >> >You can track the code along slab_alloc() ->...->__alloc_pages_nodemask() > >> > >> slab_alloc() pass NUMA_NO_NODE down, so I am lost in where the > >> preferred_nid is assigned. > >> > >You can follow: > >[ 5.773618] new_slab+0xa9/0x570 > >[ 5.773618] ___slab_alloc+0x375/0x540 > >[ 5.773618] ? pinctrl_bind_pins+0x2b/0x2a0 > >where static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node) > > > > Well, thanks for your patience, but I still don't get it. > > new_slab(node) > allocate_slab(node) > alloc_slab_page(node) > if (node == NUMA_NO_NODE) > alloc_pages() > eles > __alloc_pages_node(node) > > As you mentioned, this starts from slab_alloc() which pass NUMA_NO_NODE. > This means it goes to alloc_pages() and then alloc_pages_current() -> > __alloc_pages_nodemask(). Here we use policy_node() to get the > preferred_nid. > > I didn't catch the relathionship between policy_node() and > device->numa_node. Maybe I got wrong in some place. Would you minding > sharing more? > Have uploaded the full panic log. Enjoy it. Regards, Pingfan
