[PATCH 5.10 020/188] IB/hfi1: Fix probe time panic when AIP is enabled with a buggy BIOS

From: Greg Kroah-Hartman
Date: Mon Apr 12 2021 - 05:05:48 EST


From: Mike Marciniszyn <mike.marciniszyn@xxxxxxxxxxxxxxxxxxxx>

commit 5de61a47eb9064cbbc5f3360d639e8e34a690a54 upstream.

A panic can result when AIP is enabled:

BUG: unable to handle kernel NULL pointer dereference at 000000000000000
PGD 0 P4D 0
Oops: 0000 1 SMP PTI
CPU: 70 PID: 981 Comm: systemd-udevd Tainted: G OE --------- - - 4.18.0-240.el8.x86_64 #1
Hardware name: Intel Corporation S2600KP/S2600KP, BIOS SE5C610.86B.01.01.0005.101720141054 10/17/2014
RIP: 0010:__bitmap_and+0x1b/0x70
RSP: 0018:ffff99aa0845f9f0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8d5a6fc18000 RCX: 0000000000000048
RDX: 0000000000000000 RSI: ffffffffc06336f0 RDI: ffff8d5a8fa67750
RBP: 0000000000000079 R08: 0000000fffffffff R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffffffffc06336f0
R13: 00000000000000a0 R14: ffff8d5a6fc18000 R15: 0000000000000003
FS: 00007fec137a5980(0000) GS:ffff8d5a9fa80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000a04b48002 CR4: 00000000001606e0
Call Trace:
hfi1_num_netdev_contexts+0x7c/0x110 [hfi1]
hfi1_init_dd+0xd7f/0x1a90 [hfi1]
? pci_bus_read_config_dword+0x49/0x70
? pci_mmcfg_read+0x3e/0xe0
do_init_one.isra.18+0x336/0x640 [hfi1]
local_pci_probe+0x41/0x90
pci_device_probe+0x105/0x1c0
really_probe+0x212/0x440
driver_probe_device+0x49/0xc0
device_driver_attach+0x50/0x60
__driver_attach+0x61/0x130
? device_driver_attach+0x60/0x60
bus_for_each_dev+0x77/0xc0
? klist_add_tail+0x3b/0x70
bus_add_driver+0x14d/0x1e0
? dev_init+0x10b/0x10b [hfi1]
driver_register+0x6b/0xb0
? dev_init+0x10b/0x10b [hfi1]
hfi1_mod_init+0x1e6/0x20a [hfi1]
do_one_initcall+0x46/0x1c3
? free_unref_page_commit+0x91/0x100
? _cond_resched+0x15/0x30
? kmem_cache_alloc_trace+0x140/0x1c0
do_init_module+0x5a/0x220
load_module+0x14b4/0x17e0
? __do_sys_finit_module+0xa8/0x110
__do_sys_finit_module+0xa8/0x110
do_syscall_64+0x5b/0x1a0

The issue happens when pcibus_to_node() returns NO_NUMA_NODE.

Fix this issue by moving the initialization of dd->node to hfi1_devdata
allocation and remove the other pcibus_to_node() calls in the probe path
and use dd->node instead.

Affinity logic is adjusted to use a new field dd->affinity_entry as a
guard instead of dd->node.

Fixes: 4730f4a6c6b2 ("IB/hfi1: Activate the dummy netdev")
Link: https://lore.kernel.org/r/1617025700-31865-4-git-send-email-dennis.dalessandro@xxxxxxxxxxxxxxxxxxxx
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/infiniband/hw/hfi1/affinity.c | 21 +++++----------------
drivers/infiniband/hw/hfi1/hfi.h | 1 +
drivers/infiniband/hw/hfi1/init.c | 10 +++++++++-
drivers/infiniband/hw/hfi1/netdev_rx.c | 3 +--
4 files changed, 16 insertions(+), 19 deletions(-)

--- a/drivers/infiniband/hw/hfi1/affinity.c
+++ b/drivers/infiniband/hw/hfi1/affinity.c
@@ -632,22 +632,11 @@ static void _dev_comp_vect_cpu_mask_clea
*/
int hfi1_dev_affinity_init(struct hfi1_devdata *dd)
{
- int node = pcibus_to_node(dd->pcidev->bus);
struct hfi1_affinity_node *entry;
const struct cpumask *local_mask;
int curr_cpu, possible, i, ret;
bool new_entry = false;

- /*
- * 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);
if (cpumask_first(local_mask) >= nr_cpu_ids)
local_mask = topology_core_cpumask(0);
@@ -660,7 +649,7 @@ int hfi1_dev_affinity_init(struct hfi1_d
* create an entry in the global affinity structure and initialize it.
*/
if (!entry) {
- entry = node_affinity_allocate(node);
+ entry = node_affinity_allocate(dd->node);
if (!entry) {
dd_dev_err(dd,
"Unable to allocate global affinity node\n");
@@ -751,6 +740,7 @@ int hfi1_dev_affinity_init(struct hfi1_d
if (new_entry)
node_affinity_add_tail(entry);

+ dd->affinity_entry = entry;
mutex_unlock(&node_affinity.lock);

return 0;
@@ -766,10 +756,9 @@ void hfi1_dev_affinity_clean_up(struct h
{
struct hfi1_affinity_node *entry;

- if (dd->node < 0)
- return;
-
mutex_lock(&node_affinity.lock);
+ if (!dd->affinity_entry)
+ goto unlock;
entry = node_affinity_lookup(dd->node);
if (!entry)
goto unlock;
@@ -780,8 +769,8 @@ void hfi1_dev_affinity_clean_up(struct h
*/
_dev_comp_vect_cpu_mask_clean_up(dd, entry);
unlock:
+ dd->affinity_entry = NULL;
mutex_unlock(&node_affinity.lock);
- dd->node = NUMA_NO_NODE;
}

/*
--- a/drivers/infiniband/hw/hfi1/hfi.h
+++ b/drivers/infiniband/hw/hfi1/hfi.h
@@ -1409,6 +1409,7 @@ struct hfi1_devdata {
spinlock_t irq_src_lock;
int vnic_num_vports;
struct net_device *dummy_netdev;
+ struct hfi1_affinity_node *affinity_entry;

/* Keeps track of IPoIB RSM rule users */
atomic_t ipoib_rsm_usr_num;
--- a/drivers/infiniband/hw/hfi1/init.c
+++ b/drivers/infiniband/hw/hfi1/init.c
@@ -1277,7 +1277,6 @@ static struct hfi1_devdata *hfi1_alloc_d
dd->pport = (struct hfi1_pportdata *)(dd + 1);
dd->pcidev = pdev;
pci_set_drvdata(pdev, dd);
- dd->node = NUMA_NO_NODE;

ret = xa_alloc_irq(&hfi1_dev_table, &dd->unit, dd, xa_limit_32b,
GFP_KERNEL);
@@ -1287,6 +1286,15 @@ static struct hfi1_devdata *hfi1_alloc_d
goto bail;
}
rvt_set_ibdev_name(&dd->verbs_dev.rdi, "%s_%d", class_name(), dd->unit);
+ /*
+ * If the BIOS does not have the NUMA node information set, select
+ * NUMA 0 so we get consistent performance.
+ */
+ dd->node = pcibus_to_node(pdev->bus);
+ if (dd->node == NUMA_NO_NODE) {
+ dd_dev_err(dd, "Invalid PCI NUMA node. Performance may be affected\n");
+ dd->node = 0;
+ }

/*
* Initialize all locks for the device. This needs to be as early as
--- a/drivers/infiniband/hw/hfi1/netdev_rx.c
+++ b/drivers/infiniband/hw/hfi1/netdev_rx.c
@@ -173,8 +173,7 @@ u32 hfi1_num_netdev_contexts(struct hfi1
return 0;
}

- cpumask_and(node_cpu_mask, cpu_mask,
- cpumask_of_node(pcibus_to_node(dd->pcidev->bus)));
+ cpumask_and(node_cpu_mask, cpu_mask, cpumask_of_node(dd->node));

available_cpus = cpumask_weight(node_cpu_mask);