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net: mana: Fix accessing freed irq affinity_hint

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After calling irq_set_affinity_and_hint(), the cpumask pointer is
saved in desc->affinity_hint, and will be used later when reading
/proc/irq/<num>/affinity_hint. So the cpumask variable needs to be
persistent. Otherwise, we are accessing freed memory when reading
the affinity_hint file.

Also, need to clear affinity_hint before free_irq(), otherwise there
is a one-time warning and stack trace during module unloading:

 [  243.948687] WARNING: CPU: 10 PID: 1589 at kernel/irq/manage.c:1913 free_irq+0x318/0x360
 ...
 [  243.948753] Call Trace:
 [  243.948754]  <TASK>
 [  243.948760]  mana_gd_remove_irqs+0x78/0xc0 [mana]
 [  243.948767]  mana_gd_remove+0x3e/0x80 [mana]
 [  243.948773]  pci_device_remove+0x3d/0xb0
 [  243.948778]  device_remove+0x46/0x70
 [  243.948782]  device_release_driver_internal+0x1fe/0x280
 [  243.948785]  driver_detach+0x4e/0xa0
 [  243.948787]  bus_remove_driver+0x70/0xf0
 [  243.948789]  driver_unregister+0x35/0x60
 [  243.948792]  pci_unregister_driver+0x44/0x90
 [  243.948794]  mana_driver_exit+0x14/0x3fe [mana]
 [  243.948800]  __do_sys_delete_module.constprop.0+0x185/0x2f0

To fix the bug, use the persistent mask, cpumask_of(cpu#), and set
affinity_hint to NULL before freeing the IRQ, as required by free_irq().

Cc: stable@vger.kernel.org
Fixes: 71fa6887ee ("net: mana: Assign interrupts to CPUs based on NUMA nodes")
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/1675718929-19565-1-git-send-email-haiyangz@microsoft.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Haiyang Zhang 2023-02-06 13:28:49 -08:00 committed by Jakub Kicinski
parent b1f4fbabbb
commit 18a048370b
1 changed files with 11 additions and 26 deletions
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37
drivers/net/ethernet/microsoft/mana/gdma_main.c
View file

@ -1217,9 +1217,7 @@ static int mana_gd_setup_irqs(struct pci_dev *pdev)
unsigned int max_queues_per_port = num_online_cpus();
struct gdma_context *gc = pci_get_drvdata(pdev);
struct gdma_irq_context *gic;
unsigned int max_irqs;
u16 *cpus;
cpumask_var_t req_mask;
unsigned int max_irqs, cpu;
int nvec, irq;
int err, i = 0, j;
@ -1240,21 +1238,7 @@ static int mana_gd_setup_irqs(struct pci_dev *pdev)
goto free_irq_vector;
}
if (!zalloc_cpumask_var(&req_mask, GFP_KERNEL)) {
err = -ENOMEM;
goto free_irq;
}
cpus = kcalloc(nvec, sizeof(*cpus), GFP_KERNEL);
if (!cpus) {
err = -ENOMEM;
goto free_mask;
}
for (i = 0; i < nvec; i++)
cpus[i] = cpumask_local_spread(i, gc->numa_node);
for (i = 0; i < nvec; i++) {
cpumask_set_cpu(cpus[i], req_mask);
gic = &gc->irq_contexts[i];
gic->handler = NULL;
gic->arg = NULL;
@ -1269,17 +1253,16 @@ static int mana_gd_setup_irqs(struct pci_dev *pdev)
irq = pci_irq_vector(pdev, i);
if (irq < 0) {
err = irq;
goto free_mask;
goto free_irq;
}
err = request_irq(irq, mana_gd_intr, 0, gic->name, gic);
if (err)
goto free_mask;
irq_set_affinity_and_hint(irq, req_mask);
cpumask_clear(req_mask);
goto free_irq;
cpu = cpumask_local_spread(i, gc->numa_node);
irq_set_affinity_and_hint(irq, cpumask_of(cpu));
}
free_cpumask_var(req_mask);
kfree(cpus);
err = mana_gd_alloc_res_map(nvec, &gc->msix_resource);
if (err)
@ -1290,13 +1273,12 @@ static int mana_gd_setup_irqs(struct pci_dev *pdev)
return 0;
free_mask:
free_cpumask_var(req_mask);
kfree(cpus);
free_irq:
for (j = i - 1; j >= 0; j--) {
irq = pci_irq_vector(pdev, j);
gic = &gc->irq_contexts[j];
irq_update_affinity_hint(irq, NULL);
free_irq(irq, gic);
}
@ -1324,6 +1306,9 @@ static void mana_gd_remove_irqs(struct pci_dev *pdev)
continue;
gic = &gc->irq_contexts[i];
/* Need to clear the hint before free_irq */
irq_update_affinity_hint(irq, NULL);
free_irq(irq, gic);
}