I got a page fault report when doing fault injection test:
BUG: unable to handle page fault for address: fffffffffffffff4
...
RIP: 0010:sysfs_remove_groups+0x25/0x60
...
Call Trace:
msi_destroy_sysfs+0x30/0xa0
free_msi_irqs+0x11d/0x1b0
__pci_enable_msix_range+0x67f/0x760
pci_alloc_irq_vectors_affinity+0xe7/0x170
vp_find_vqs_msix+0x129/0x560
vp_find_vqs+0x52/0x230
vp_modern_find_vqs+0x47/0xb0
p9_virtio_probe+0xa1/0x460 [9pnet_virtio]
virtio_dev_probe+0x1ed/0x2e0
really_probe+0x1c7/0x400
__driver_probe_device+0xa4/0x120
driver_probe_device+0x32/0xe0
__driver_attach+0xbf/0x130
bus_for_each_dev+0xbb/0x110
driver_attach+0x27/0x30
bus_add_driver+0x1d9/0x270
driver_register+0xa9/0x180
register_virtio_driver+0x31/0x50
p9_virtio_init+0x3c/0x1000 [9pnet_virtio]
do_one_initcall+0x7b/0x380
do_init_module+0x5f/0x21e
load_module+0x265c/0x2c60
__do_sys_finit_module+0xb0/0xf0
__x64_sys_finit_module+0x1a/0x20
do_syscall_64+0x34/0xb0
entry_SYSCALL_64_after_hwframe+0x44/0xae
When populating msi_irqs sysfs failed in msi_capability_init() or
msix_capability_init(), dev->msi_irq_groups will point to ERR_PTR(...).
This will cause a page fault when destroying the wrong
dev->msi_irq_groups in free_msi_irqs().
Fix this by setting dev->msi_irq_groups to NULL when msi_populate_sysfs()
failed.
Fixes: 2f170814bdd2 ("genirq/msi: Move MSI sysfs handling from PCI to MSI core")
Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
Signed-off-by: Wang Hai <wanghai38@xxxxxxxxxx>
---
drivers/pci/msi.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index 0099a00af361..6f75db9f3be7 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -561,6 +561,7 @@ static int msi_capability_init(struct pci_dev *dev, int nvec,
dev->msi_irq_groups = msi_populate_sysfs(&dev->dev);
if (IS_ERR(dev->msi_irq_groups)) {
ret = PTR_ERR(dev->msi_irq_groups);
+ dev->msi_irq_groups = NULL;
goto err;
}
@@ -733,6 +734,7 @@ static int msix_capability_init(struct pci_dev *dev, struct msix_entry *entries,
dev->msi_irq_groups = msi_populate_sysfs(&dev->dev);
if (IS_ERR(dev->msi_irq_groups)) {
ret = PTR_ERR(dev->msi_irq_groups);
+ dev->msi_irq_groups = NULL;
goto out_free;
}
--
2.17.1
