ucc_geth: Fix three oopses in PHY {de,}initialization code
When there are no free snums, UCC ethernet should gracefully fail, but
currently it oopses this way:
# ifconfig eth0 up
fill_init_enet_entries: Can not get SNUM.
ucc_geth_startup: Can not fill p_init_enet_param_shadow.
eth0: Cannot configure net device, aborting.
Unable to handle kernel paging request for data at address 0x00000190
Faulting instruction address: 0xc0294c88
Oops: Kernel access of bad area, sig: 11 [#1]
[...]
NIP [c0294c88] mutex_lock+0x0/0x1c
LR [c01b6be8] phy_stop+0x20/0x70
Call Trace:
[efb25da0] [efb2eb60] 0xefb2eb60 (unreliable)
[efb25db0] [c01b2058] ucc_geth_stop+0x2c/0x8c
[efb25dd0] [c01b4194] ucc_geth_open+0x48/0x27c
[efb25df0] [c020eec0] dev_open+0xc0/0x118
[...]
This is because the ucc_geth_stop() routine assumes that ugeth->phydev
is always initialized by the ucc_geth_open(), while it is not in case
of errors.
If we add a check to the ucc_geth_stop(), then another oops pops up:
Unable to handle kernel paging request for data at address 0x00000004
Faulting instruction address: 0xc01b46a4
Oops: Kernel access of bad area, sig: 11 [#1]
[...]
NIP [c01b46a4] adjust_link+0x20/0x1b4
LR [c01b770c] phy_state_machine+0xdc/0x44c
Call Trace:
[ef83bf10] [c021b388] linkwatch_schedule_work+0x74/0xf8 (unreliable)
[ef83bf40] [c01b770c] phy_state_machine+0xdc/0x44c
[ef83bf60] [c004c13c] run_workqueue+0xb8/0x148
[ef83bf90] [c004c870] worker_thread+0x70/0xd0
[ef83bfd0] [c00505fc] kthread+0x48/0x84
[ef83bff0] [c000f464] kernel_thread+0x4c/0x68
[...]
That one happens because ucc_geth_stop() does not call phy_disconnect()
and so phylib state machine is running without any idea that a MAC has
just died.
Also, when device tree specifies fixed-link, and CONFIG_FIXED_PHY
is disabled, we'll get this oops:
0:01 not found
eth2: Could not attach to PHY
eth2: Cannot initialize PHY, aborting.
Unable to handle kernel paging request for data at address 0x00000190
Faulting instruction address: 0xc02967d0
Oops: Kernel access of bad area, sig: 11 [#1]
[...]
NIP [c02967d0] mutex_lock+0x0/0x1c
LR [c01b6bcc] phy_stop+0x20/0x70
Call Trace:
[ef82be50] [efb6bb60] 0xefb6bb60 (unreliable)
[ef82be60] [c01b2058] ucc_geth_stop+0x2c/0x8c
[ef82be80] [c01b4194] ucc_geth_open+0x48/0x27c
[ef82bea0] [c0210a04] dev_open+0xc0/0x118
[ef82bec0] [c020f85c] dev_change_flags+0x84/0x1ac
[ef82bee0] [c037b768] ic_open_devs+0x168/0x2bc
[ef82bf20] [c037ca98] ip_auto_config+0x90/0x28c
[ef82bf60] [c0001b9c] do_one_initcall+0x34/0x1a0
[ef82bfd0] [c035e240] do_initcalls+0x38/0x58
[ef82bfe0] [c035e2c4] kernel_init+0x30/0x90
[ef82bff0] [c000f464] kernel_thread+0x4c/0x68
[...]
And again, ucc_geth_stop() assumes that ugeth->phydev is there, while
it isn't.
This patch fixes all three oopses simply by rearranging some code:
- In ucc_geth_open(): move init_phy() call to the beginning, so
that we only call ucc_geth_stop() with a PHY attached;
- Move phy_disconnect() call from ucc_geth_close() to
ucc_geth_stop(), so that we'll always disconnect the PHY.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ucc_geth.c b/drivers/net/ucc_geth.c
index a110326..86a479f 100644
--- a/drivers/net/ucc_geth.c
+++ b/drivers/net/ucc_geth.c
@@ -2009,6 +2009,9 @@
/* Disable Rx and Tx */
clrbits32(&ug_regs->maccfg1, MACCFG1_ENABLE_RX | MACCFG1_ENABLE_TX);
+ phy_disconnect(ugeth->phydev);
+ ugeth->phydev = NULL;
+
ucc_geth_memclean(ugeth);
}
@@ -3345,6 +3348,14 @@
return -EINVAL;
}
+ err = init_phy(dev);
+ if (err) {
+ if (netif_msg_ifup(ugeth))
+ ugeth_err("%s: Cannot initialize PHY, aborting.",
+ dev->name);
+ return err;
+ }
+
err = ucc_struct_init(ugeth);
if (err) {
if (netif_msg_ifup(ugeth))
@@ -3381,13 +3392,6 @@
&ugeth->ug_regs->macstnaddr1,
&ugeth->ug_regs->macstnaddr2);
- err = init_phy(dev);
- if (err) {
- if (netif_msg_ifup(ugeth))
- ugeth_err("%s: Cannot initialize PHY, aborting.", dev->name);
- goto out_err;
- }
-
phy_start(ugeth->phydev);
err = ugeth_enable(ugeth, COMM_DIR_RX_AND_TX);
@@ -3430,9 +3434,6 @@
free_irq(ugeth->ug_info->uf_info.irq, ugeth->dev);
- phy_disconnect(ugeth->phydev);
- ugeth->phydev = NULL;
-
netif_stop_queue(dev);
return 0;