5.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Peiyang Wang <wangpeiyang1@xxxxxxxxxx>
[ Upstream commit df3dff8ab6d79edc942464999d06fbaedf8cdd18 ]
When the driver is uninstalled and the VF is disabled concurrently, a
kernel crash occurs. The reason is that the two actions call function
pci_disable_sriov(). The num_VFs is checked to determine whether to
release the corresponding resources. During the second calling, num_VFs
is not 0 and the resource release function is called. However, the
corresponding resource has been released during the first invoking.
Therefore, the problem occurs:
[15277.839633][T50670] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020
...
[15278.131557][T50670] Call trace:
[15278.134686][T50670] klist_put+0x28/0x12c
[15278.138682][T50670] klist_del+0x14/0x20
[15278.142592][T50670] device_del+0xbc/0x3c0
[15278.146676][T50670] pci_remove_bus_device+0x84/0x120
[15278.151714][T50670] pci_stop_and_remove_bus_device+0x6c/0x80
[15278.157447][T50670] pci_iov_remove_virtfn+0xb4/0x12c
[15278.162485][T50670] sriov_disable+0x50/0x11c
[15278.166829][T50670] pci_disable_sriov+0x24/0x30
[15278.171433][T50670] hnae3_unregister_ae_algo_prepare+0x60/0x90 [hnae3]
[15278.178039][T50670] hclge_exit+0x28/0xd0 [hclge]
[15278.182730][T50670] __se_sys_delete_module.isra.0+0x164/0x230
[15278.188550][T50670] __arm64_sys_delete_module+0x1c/0x30
[15278.193848][T50670] invoke_syscall+0x50/0x11c
[15278.198278][T50670] el0_svc_common.constprop.0+0x158/0x164
[15278.203837][T50670] do_el0_svc+0x34/0xcc
[15278.207834][T50670] el0_svc+0x20/0x30
For details, see the following figure.
rmmod hclge disable VFs
----------------------------------------------------
hclge_exit() sriov_numvfs_store()
... device_lock()
pci_disable_sriov() hns3_pci_sriov_configure()
pci_disable_sriov()
sriov_disable()
sriov_disable() if !num_VFs :
if !num_VFs : return;
return; sriov_del_vfs()
sriov_del_vfs() ...
... klist_put()
klist_put() ...
... num_VFs = 0;
num_VFs = 0; device_unlock();
In this patch, when driver is removing, we get the device_lock()
to protect num_VFs, just like sriov_numvfs_store().
Fixes: 0dd8a25f355b ("net: hns3: disable sriov before unload hclge layer")
Signed-off-by: Peiyang Wang <wangpeiyang1@xxxxxxxxxx>
Signed-off-by: Jijie Shao <shaojijie@xxxxxxxxxx>
Reviewed-by: Simon Horman <horms@xxxxxxxxxx>
Link: https://patch.msgid.link/20241101091507.3644584-1-shaojijie@xxxxxxxxxx
Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/hisilicon/hns3/hnae3.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/hisilicon/hns3/hnae3.c b/drivers/net/ethernet/hisilicon/hns3/hnae3.c
index 2e38c7d214c45..6c7cef6f1532f 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hnae3.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hnae3.c
@@ -25,8 +25,11 @@ void hnae3_unregister_ae_algo_prepare(struct hnae3_ae_algo *ae_algo)
pci_id = pci_match_id(ae_algo->pdev_id_table, ae_dev->pdev);
if (!pci_id)
continue;
- if (IS_ENABLED(CONFIG_PCI_IOV))
+ if (IS_ENABLED(CONFIG_PCI_IOV)) {
+ device_lock(&ae_dev->pdev->dev);
pci_disable_sriov(ae_dev->pdev);
+ device_unlock(&ae_dev->pdev->dev);
+ }
}
}
EXPORT_SYMBOL(hnae3_unregister_ae_algo_prepare);
--
2.43.0
