From c5643cab7bf663ae049b11be43de8819683176dd Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Mon, 23 Jun 2008 10:41:23 +0200 Subject: [netdrvr] 3c59x: remove irqs_disabled warning from local_bh_enable Original Author: Michael Buesch net, vortex: fix lockup Ingo Molnar reported: -tip testing found that Johannes Berg's "softirq: remove irqs_disabled warning from local_bh_enable" enhancement to lockdep triggers a new warning on an old testbox that uses 3c59x vortex and netlogging: -----> calling vortex_init+0x0/0xb0 PCI: Found IRQ 10 for device 0000:00:0b.0 PCI: Sharing IRQ 10 with 0000:00:0a.0 PCI: Sharing IRQ 10 with 0000:00:0b.1 3c59x: Donald Becker and others. 0000:00:0b.0: 3Com PCI 3c556 Laptop Tornado at e0800400. PCI: Enabling bus mastering for device 0000:00:0b.0 initcall vortex_init+0x0/0xb0 returned 0 after 47 msecs ... calling init_netconsole+0x0/0x1b0 netconsole: local port 4444 netconsole: local IP 10.0.1.9 netconsole: interface eth0 netconsole: remote port 4444 netconsole: remote IP 10.0.1.16 netconsole: remote ethernet address 00:19:xx:xx:xx:xx netconsole: device eth0 not up yet, forcing it eth0: setting half-duplex. eth0: setting full-duplex. ------------[ cut here ]------------ WARNING: at kernel/softirq.c:137 local_bh_enable_ip+0xd1/0xe0() Pid: 1, comm: swapper Not tainted 2.6.26-rc6-tip #2091 [] warn_on_slowpath+0x4f/0x70 [] ? release_console_sem+0x1b4/0x1d0 [] ? vprintk+0x2a0/0x450 [] ? __mod_timer+0xa5/0xc0 [] ? mdio_sync+0x3d/0x50 [] ? marker_probe_cb+0x46/0xa0 [] ? printk+0x27/0x50 [] ? vortex_set_duplex+0x43/0xc0 [] ? vortex_set_duplex+0xa1/0xc0 [] ? vortex_timer+0xe2/0x3e0 [] local_bh_enable_ip+0xd1/0xe0 [] _spin_unlock_bh+0x2f/0x40 [] vortex_timer+0xe2/0x3e0 [] ? trace_hardirqs_on+0xb/0x10 [] ? trace_hardirqs_on_caller+0x88/0x160 [] run_timer_softirq+0x162/0x1c0 [] ? vortex_timer+0x0/0x3e0 [] local_bh_enable_ip+0xd1/0xe0 [] _spin_unlock_bh+0x2f/0x40 [] vortex_timer+0xe2/0x3e0 [] ? trace_hardirqs_on+0xb/0x10 [] ? trace_hardirqs_on_caller+0x88/0x160 [] run_timer_softirq+0x162/0x1c0 [] ? vortex_timer+0x0/0x3e0 [] ? vortex_timer+0x0/0x3e0 [] __do_softirq+0x9a/0x160 [] ? __do_softirq+0x0/0x160 [] call_on_stack+0x15/0x30 [] ? irq_exit+0x55/0x60 [] ? do_IRQ+0x85/0xd0 [] ? trace_hardirqs_on_caller+0xc1/0x160 [] ? common_interrupt+0x28/0x30 [] ? mutex_unlock+0x8/0x10 [] ? _cond_resched+0x10/0x30 [] ? netpoll_setup+0x117/0x390 [] ? init_netconsole+0x14e/0x1b0 [] ? ktime_get+0x19/0x40 [] ? kernel_init+0x1b2/0x2c0 [] ? init_netconsole+0x0/0x1b0 [] ? trace_hardirqs_on_thunk+0xc/0x10 [] ? restore_nocheck_notrace+0x0/0xe [] ? kernel_init+0x0/0x2c0 [] ? kernel_init+0x0/0x2c0 [] ? kernel_thread_helper+0x7/0x10 ======================= ---[ end trace 37f9c502aff112e0 ]--- console [netcon0] enabled netconsole: network logging started initcall init_netconsole+0x0/0x1b0 returned 0 after 2914 msecs looking at the driver I think the bug is real and the fix actually is trivial. vp->lock is also taken in hardware IRQ context, so we _have_ to always use irqsafe locking. As we run in a timer with IRQs disabled, we can simply use spin_lock. Cc: Signed-off-by: Ingo Molnar Signed-off-by: Jeff Garzik --- drivers/net/3c59x.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'drivers/net/3c59x.c') diff --git a/drivers/net/3c59x.c b/drivers/net/3c59x.c index 2edda8cc7f99..aabad8ce7458 100644 --- a/drivers/net/3c59x.c +++ b/drivers/net/3c59x.c @@ -1768,9 +1768,10 @@ vortex_timer(unsigned long data) case XCVR_MII: case XCVR_NWAY: { ok = 1; - spin_lock_bh(&vp->lock); + /* Interrupts are already disabled */ + spin_lock(&vp->lock); vortex_check_media(dev, 0); - spin_unlock_bh(&vp->lock); + spin_unlock(&vp->lock); } break; default: /* Other media types handled by Tx timeouts. */ -- cgit v1.2.1