[PATCH 4.14 033/115] IB/hfi1: Invalid NUMA node information can cause a divide by zero

From: Greg Kroah-Hartman
Date: Thu Sep 13 2018 - 09:43:22 EST


4.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: "Michael J. Ruhl" <michael.j.ruhl@xxxxxxxxx>

[ Upstream commit c513de490f808d8480346f9a58e6a4a5f3de12e7 ]

If the system BIOS does not supply NUMA node information to the
PCI devices, the NUMA node is selected by choosing the current
node.

This can lead to the following crash:

divide error: 0000 SMP
CPU: 0 PID: 4 Comm: kworker/0:0 Tainted: G IOE
------------ 3.10.0-693.21.1.el7.x86_64 #1
Hardware name: Intel Corporation S2600KP/S2600KP, BIOS
SE5C610.86B.01.01.0005.101720141054 10/17/2014
Workqueue: events work_for_cpu_fn
task: ffff880174480fd0 ti: ffff880174488000 task.ti: ffff880174488000
RIP: 0010: [<ffffffffc020ac69>] hfi1_dev_affinity_init+0x129/0x6a0 [hfi1]
RSP: 0018:ffff88017448bbf8 EFLAGS: 00010246
RAX: 0000000000000011 RBX: ffff88107ffba6c0 RCX: ffff88085c22e130
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff880824ad0000
RBP: ffff88017448bc48 R08: 0000000000000011 R09: 0000000000000002
R10: ffff8808582b6ca0 R11: 0000000000003151 R12: ffff8808582b6ca0
R13: ffff8808582b6518 R14: ffff8808582b6010 R15: 0000000000000012
FS: 0000000000000000(0000) GS:ffff88085ec00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007efc707404f0 CR3: 0000000001a02000 CR4: 00000000001607f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
hfi1_init_dd+0x14b3/0x27a0 [hfi1]
? pcie_capability_write_word+0x46/0x70
? hfi1_pcie_init+0xc0/0x200 [hfi1]
do_init_one+0x153/0x4c0 [hfi1]
? sched_clock_cpu+0x85/0xc0
init_one+0x1b5/0x260 [hfi1]
local_pci_probe+0x4a/0xb0
work_for_cpu_fn+0x1a/0x30
process_one_work+0x17f/0x440
worker_thread+0x278/0x3c0
? manage_workers.isra.24+0x2a0/0x2a0
kthread+0xd1/0xe0
? insert_kthread_work+0x40/0x40
ret_from_fork+0x77/0xb0
? insert_kthread_work+0x40/0x40

If the BIOS is not supplying NUMA information:
- set the default table count to 1 for all possible nodes
- select node 0 (instead of current NUMA) node to get consistent
performance
- generate an error indicating that the BIOS should be upgraded

Reviewed-by: Gary Leshner <gary.s.leshner@xxxxxxxxx>
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@xxxxxxxxx>
Signed-off-by: Michael J. Ruhl <michael.j.ruhl@xxxxxxxxx>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@xxxxxxxxx>

Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>

Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/infiniband/hw/hfi1/affinity.c | 24 +++++++++++++++++++++---
1 file changed, 21 insertions(+), 3 deletions(-)

--- a/drivers/infiniband/hw/hfi1/affinity.c
+++ b/drivers/infiniband/hw/hfi1/affinity.c
@@ -146,7 +146,7 @@ int node_affinity_init(void)
while ((dev = pci_get_device(ids->vendor, ids->device, dev))) {
node = pcibus_to_node(dev->bus);
if (node < 0)
- node = numa_node_id();
+ goto out;

hfi1_per_node_cntr[node]++;
}
@@ -154,6 +154,18 @@ int node_affinity_init(void)
}

return 0;
+
+out:
+ /*
+ * Invalid PCI NUMA node information found, note it, and populate
+ * our database 1:1.
+ */
+ pr_err("HFI: Invalid PCI NUMA node. Performance may be affected\n");
+ pr_err("HFI: System BIOS may need to be upgraded\n");
+ for (node = 0; node < node_affinity.num_possible_nodes; node++)
+ hfi1_per_node_cntr[node] = 1;
+
+ return 0;
}

void node_affinity_destroy(void)
@@ -227,8 +239,14 @@ int hfi1_dev_affinity_init(struct hfi1_d
const struct cpumask *local_mask;
int curr_cpu, possible, i;

- if (node < 0)
- node = numa_node_id();
+ /*
+ * If the BIOS does not have the NUMA node information set, select
+ * NUMA 0 so we get consistent performance.
+ */
+ if (node < 0) {
+ dd_dev_err(dd, "Invalid PCI NUMA node. Performance may be affected\n");
+ node = 0;
+ }
dd->node = node;

local_mask = cpumask_of_node(dd->node);