of, numa: Return NUMA_NO_NODE from disable of_node_to_nid() if nid not possible.
authorDavid Daney <david.daney@cavium.com>
Fri, 28 Oct 2016 21:15:02 +0000 (14:15 -0700)
committerRob Herring <robh@kernel.org>
Tue, 15 Nov 2016 15:17:12 +0000 (09:17 -0600)
commitb6cc9474e2dd9f0c19b694b40961d81117f1e918
treef650565240c78ba135cb2ed64eb58a3aa31f00c2
parent2092c1dbf3f9a1602a09f24fe5923897327231d2
of, numa: Return NUMA_NO_NODE from disable of_node_to_nid() if nid not possible.

On arm64 NUMA kernels we can pass "numa=off" on the command line to
disable NUMA.  A side effect of this is that kmalloc_node() calls to
non-zero nodes will crash the system with an OOPS:

[    0.000000] ITS@0x0000901000020000: allocated 2097152 Devices @10002000000 (flat, esz 8, psz 64K, shr 1)
[    0.000000] Unable to handle kernel NULL pointer dereference at virtual address 00001680
[    0.000000] pgd = fffffc0009470000
[    0.000000] [00001680] *pgd=0000010ffff90003, *pud=0000010ffff90003, *pmd=0000010ffff90003, *pte=0000000000000000
[    0.000000] Internal error: Oops: 96000006 [#1] SMP
.
.
.
[    0.000000] [<fffffc00081c8950>] __alloc_pages_nodemask+0xa4/0xe68
[    0.000000] [<fffffc000821fa70>] new_slab+0xd0/0x564
[    0.000000] [<fffffc0008221e24>] ___slab_alloc+0x2e4/0x514
[    0.000000] [<fffffc0008239498>] __slab_alloc+0x48/0x58
[    0.000000] [<fffffc0008222c20>] __kmalloc_node+0xd0/0x2dc
[    0.000000] [<fffffc0008115374>] __irq_domain_add+0x7c/0x164
[    0.000000] [<fffffc0008b461dc>] its_probe+0x784/0x81c
[    0.000000] [<fffffc0008b462bc>] its_init+0x48/0x1b0
[    0.000000] [<fffffc0008b4543c>] gic_init_bases+0x228/0x360
[    0.000000] [<fffffc0008b456bc>] gic_of_init+0x148/0x1cc
[    0.000000] [<fffffc0008b5aec8>] of_irq_init+0x184/0x298
[    0.000000] [<fffffc0008b43f9c>] irqchip_init+0x14/0x38
[    0.000000] [<fffffc0008b12d60>] init_IRQ+0xc/0x30
[    0.000000] [<fffffc0008b10a3c>] start_kernel+0x240/0x3b8
[    0.000000] [<fffffc0008b101c4>] __primary_switched+0x30/0x6c
[    0.000000] Code: 912ec2a0 b9403809 0a0902fb 37b007db (f9400300)
.
.
.

This is caused by code like this in kernel/irq/irqdomain.c

    domain = kzalloc_node(sizeof(*domain) + (sizeof(unsigned int) * size),
                  GFP_KERNEL, of_node_to_nid(of_node));

When NUMA is disabled, the concept of a node is really undefined, so
of_node_to_nid() should unconditionally return NUMA_NO_NODE.

Fix by returning NUMA_NO_NODE when the nid is not in the set of
possible nodes.

Reported-by: Gilbert Netzer <noname@pdc.kth.se>
Signed-off-by: David Daney <david.daney@cavium.com>
Cc: stable@vger.kernel.org # 4.7+
Signed-off-by: Rob Herring <robh@kernel.org>
drivers/of/of_numa.c