From: Claudiu Manoil claudiu.manoil@nxp.com
[ Upstream commit 26cb7085c8984e5b71d65c374a135134ed8cabb3 ]
For ENETC ports that register an external MDIO bus, the bus doesn't get removed on the error bailout path of enetc_pf_probe().
This issue became much more visible after recent: commit 07095c025ac2 ("net: enetc: Use DT protocol information to set up the ports") Before this commit, one could make probing fail on the error path only by having register_netdev() fail, which is unlikely. But after this commit, because it moved the enetc_of_phy_get() call up in the probing sequence, now we can trigger an mdiobus_free() bug just by forcing enetc_alloc_msix() to return error, i.e. with the 'pci=nomsi' kernel bootarg (since ENETC relies on MSI support to work), as the calltrace below shows:
kernel BUG at /home/eiz/work/enetc/net/drivers/net/phy/mdio_bus.c:648! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP [...] Hardware name: LS1028A RDB Board (DT) pstate: 80000005 (Nzcv daif -PAN -UAO BTYPE=--) pc : mdiobus_free+0x50/0x58 lr : devm_mdiobus_free+0x14/0x20 [...] Call trace: mdiobus_free+0x50/0x58 devm_mdiobus_free+0x14/0x20 release_nodes+0x138/0x228 devres_release_all+0x38/0x60 really_probe+0x1c8/0x368 driver_probe_device+0x5c/0xc0 device_driver_attach+0x74/0x80 __driver_attach+0x8c/0xd8 bus_for_each_dev+0x7c/0xd8 driver_attach+0x24/0x30 bus_add_driver+0x154/0x200 driver_register+0x64/0x120 __pci_register_driver+0x44/0x50 enetc_pf_driver_init+0x24/0x30 do_one_initcall+0x60/0x1c0 kernel_init_freeable+0x1fc/0x274 kernel_init+0x14/0x110 ret_from_fork+0x10/0x34
Fixes: ebfcb23d62ab ("enetc: Add ENETC PF level external MDIO support") Signed-off-by: Claudiu Manoil claudiu.manoil@nxp.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/freescale/enetc/enetc_pf.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/net/ethernet/freescale/enetc/enetc_pf.c b/drivers/net/ethernet/freescale/enetc/enetc_pf.c index b73421c3e25b1..74847aa644f12 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc_pf.c +++ b/drivers/net/ethernet/freescale/enetc/enetc_pf.c @@ -885,6 +885,7 @@ static int enetc_pf_probe(struct pci_dev *pdev, return 0;
err_reg_netdev: + enetc_mdio_remove(pf); enetc_of_put_phy(priv); enetc_free_msix(priv); err_alloc_msix: