On Fri 07-12-18 17:40:09, Pingfan Liu wrote:
> On Fri, Dec 7, 2018 at 3:53 PM Michal Hocko <mhocko@xxxxxxxxxx> wrote:
> >
> > On Fri 07-12-18 10:56:51, Pingfan Liu wrote:
> > [...]
> > > In a short word, the fix method should consider about the two factors:
> > > semantic of online-node and the effect on all archs
> >
> > I am pretty sure there is a lot of room for unification in this area.
> > Nevertheless I strongly believe the bug should be fixed firs with the
> > simplest way and all the cleanup should be done on top.
> >
> > Do I get it right that the diff worked for you and I can prepare a full
> > patch?
> >
> Sure, I am glad to test you new patch.
>From 46e68be89d9c299fd497b2b8bea3f2add144f17f Mon Sep 17 00:00:00 2001
From: Michal Hocko <mhocko@xxxxxxxx>
Date: Fri, 7 Dec 2018 12:23:32 +0100
Subject: [PATCH] x86, numa: always initialize all possible nodes
Pingfan Liu has reported the following splat
[ 5.772742] BUG: unable to handle kernel paging request at 0000000000002088
[ 5.773618] PGD 0 P4D 0
[ 5.773618] Oops: 0000 [#1] SMP NOPTI
[ 5.773618] CPU: 2 PID: 1 Comm: swapper/0 Not tainted 4.20.0-rc1+ #3
[ 5.773618] Hardware name: Dell Inc. PowerEdge R7425/02MJ3T, BIOS 1.4.3 06/29/2018
[ 5.773618] RIP: 0010:__alloc_pages_nodemask+0xe2/0x2a0
[ 5.773618] Code: 00 00 44 89 ea 80 ca 80 41 83 f8 01 44 0f 44 ea 89 da c1 ea 08 83 e2 01 88 54 24 20 48 8b 54 24 08 48 85 d2 0f 85 46 01 00 00 <3b> 77 08 0f 82 3d 01 00 00 48 89 f8 44 89 ea 48 89
e1 44 89 e6 89
[ 5.773618] RSP: 0018:ffffaa600005fb20 EFLAGS: 00010246
[ 5.773618] RAX: 0000000000000000 RBX: 00000000006012c0 RCX: 0000000000000000
[ 5.773618] RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000002080
[ 5.773618] RBP: 00000000006012c0 R08: 0000000000000000 R09: 0000000000000002
[ 5.773618] R10: 00000000006080c0 R11: 0000000000000002 R12: 0000000000000000
[ 5.773618] R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000002
[ 5.773618] FS: 0000000000000000(0000) GS:ffff8c69afe00000(0000) knlGS:0000000000000000
[ 5.773618] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 5.773618] CR2: 0000000000002088 CR3: 000000087e00a000 CR4: 00000000003406e0
[ 5.773618] Call Trace:
[ 5.773618] new_slab+0xa9/0x570
[ 5.773618] ___slab_alloc+0x375/0x540
[ 5.773618] ? pinctrl_bind_pins+0x2b/0x2a0
[ 5.773618] __slab_alloc+0x1c/0x38
[ 5.773618] __kmalloc_node_track_caller+0xc8/0x270
[ 5.773618] ? pinctrl_bind_pins+0x2b/0x2a0
[ 5.773618] devm_kmalloc+0x28/0x60
[ 5.773618] pinctrl_bind_pins+0x2b/0x2a0
[ 5.773618] really_probe+0x73/0x420
[ 5.773618] driver_probe_device+0x115/0x130
[ 5.773618] __driver_attach+0x103/0x110
[ 5.773618] ? driver_probe_device+0x130/0x130
[ 5.773618] bus_for_each_dev+0x67/0xc0
[ 5.773618] ? klist_add_tail+0x3b/0x70
[ 5.773618] bus_add_driver+0x41/0x260
[ 5.773618] ? pcie_port_setup+0x4d/0x4d
[ 5.773618] driver_register+0x5b/0xe0
[ 5.773618] ? pcie_port_setup+0x4d/0x4d
[ 5.773618] do_one_initcall+0x4e/0x1d4
[ 5.773618] ? init_setup+0x25/0x28
[ 5.773618] kernel_init_freeable+0x1c1/0x26e
[ 5.773618] ? loglevel+0x5b/0x5b
[ 5.773618] ? rest_init+0xb0/0xb0
[ 5.773618] kernel_init+0xa/0x110
[ 5.773618] ret_from_fork+0x22/0x40
[ 5.773618] Modules linked in:
[ 5.773618] CR2: 0000000000002088
[ 5.773618] ---[ end trace 1030c9120a03d081 ]---
with his AMD machine with the following topology
NUMA node0 CPU(s): 0,8,16,24
NUMA node1 CPU(s): 2,10,18,26
NUMA node2 CPU(s): 4,12,20,28
NUMA node3 CPU(s): 6,14,22,30
NUMA node4 CPU(s): 1,9,17,25
NUMA node5 CPU(s): 3,11,19,27
NUMA node6 CPU(s): 5,13,21,29
NUMA node7 CPU(s): 7,15,23,31
[ 0.007418] Early memory node ranges
[ 0.007419] node 1: [mem 0x0000000000001000-0x000000000008efff]
[ 0.007420] node 1: [mem 0x0000000000090000-0x000000000009ffff]
[ 0.007422] node 1: [mem 0x0000000000100000-0x000000005c3d6fff]
[ 0.007422] node 1: [mem 0x00000000643df000-0x0000000068ff7fff]
[ 0.007423] node 1: [mem 0x000000006c528000-0x000000006fffffff]
[ 0.007424] node 1: [mem 0x0000000100000000-0x000000047fffffff]
[ 0.007425] node 5: [mem 0x0000000480000000-0x000000087effffff]
and nr_cpus set to 4. The underlying reason is tha the device is bound
to node 2 which doesn't have any memory and init_cpu_to_node only
initializes memory-less nodes for possible cpus which nr_cpus restrics.
This in turn means that proper zonelists are not allocated and the page
allocator blows up.
Fix the issue by moving init_memory_less_node into numa_register_memblks
and always initialize all possible nodes consistently at a single place.
Reported-by: Pingfan Liu <kernelfans@xxxxxxxxx>
Signed-off-by: Michal Hocko <mhocko@xxxxxxxx>
---
arch/x86/mm/numa.c | 33 +++++++++++++++------------------
1 file changed, 15 insertions(+), 18 deletions(-)
diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c
index 1308f5408bf7..4575ae4d5449 100644
--- a/arch/x86/mm/numa.c
+++ b/arch/x86/mm/numa.c
@@ -527,6 +527,19 @@ static void __init numa_clear_kernel_node_hotplug(void)
}
}
+static void __init init_memory_less_node(int nid)
+{
+ unsigned long zones_size[MAX_NR_ZONES] = {0};
+ unsigned long zholes_size[MAX_NR_ZONES] = {0};
+
+ free_area_init_node(nid, zones_size, 0, zholes_size);
+
+ /*
+ * All zonelists will be built later in start_kernel() after per cpu
+ * areas are initialized.
+ */
+}
+
static int __init numa_register_memblks(struct numa_meminfo *mi)
{
unsigned long uninitialized_var(pfn_align);
@@ -592,6 +605,8 @@ static int __init numa_register_memblks(struct numa_meminfo *mi)
continue;
alloc_node_data(nid);
+ if (!end)
+ init_memory_less_node(nid);
}
/* Dump memblock with node info and return. */
@@ -721,21 +736,6 @@ void __init x86_numa_init(void)
numa_init(dummy_numa_init);
}
-static void __init init_memory_less_node(int nid)
-{
- unsigned long zones_size[MAX_NR_ZONES] = {0};
- unsigned long zholes_size[MAX_NR_ZONES] = {0};
-
- /* Allocate and initialize node data. Memory-less node is now online.*/
- alloc_node_data(nid);
- free_area_init_node(nid, zones_size, 0, zholes_size);
-
- /*
- * All zonelists will be built later in start_kernel() after per cpu
- * areas are initialized.
- */
-}
-
/*
* Setup early cpu_to_node.
*
@@ -763,9 +763,6 @@ void __init init_cpu_to_node(void)
if (node == NUMA_NO_NODE)
continue;
- if (!node_online(node))
- init_memory_less_node(node);
-
numa_set_node(cpu, node);
}
}
--
2.19.2
--
Michal Hocko
SUSE Labs
