From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Matt Carlson" <mcarlson@broadcom.com>
Subject: Re: tg3: Badness at kernel/mutex.c:207
Date: Mon, 28 Sep 2009 13:51:28 -0700
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Cc: "netdev@vger.kernel.org" <netdev@vger.kernel.org>
To: "Felix Radensky" <felix@embedded-sol.com>
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On Sat, Sep 26, 2009 at 02:20:57PM -0700, Felix Radensky wrote:
> Hi,
> 
> I'm running linux-2.6.31 on a custom MPC8536 based board with BCM57760 chip.
> Both tg3 driver, and Broadcom PHY driver are modules.
> 
> Each time I run ifconfig eth2 up, I get the following error message:
> 
> Badness at kernel/mutex.c:207
> NIP: c025132c LR: c0251314 CTR: c0251334
> REGS: efbedbd0 TRAP: 0700   Not tainted  (2.6.31)
> MSR: 00029000 <EE,ME,CE>  CR: 24020422  XER: 00000000
> TASK = efacce10[1080] 'ifconfig' THREAD: efbec000
> GPR00: 00000000 efbedc80 efacce10 00000001 00007020 00000002 00000000 
> 00000200
> GPR08: 00029000 c0350000 c0330000 00000001 24020424 10057d94 000002a0 
> 1000d82c
> GPR16: 1000d81c 1000d814 10010000 10050000 ef897a0c efbede18 ffff8914 
> ef897a00
> GPR24: 00008000 c034b480 efbec000 efb0122c c0350000 efacce10 ef82d2c0 
> efb01228
> NIP [c025132c] __mutex_lock_slowpath+0x1f0/0x1f8
> LR [c0251314] __mutex_lock_slowpath+0x1d8/0x1f8
> Call Trace:
> [efbedcd0] [c025134c] mutex_lock+0x18/0x34
> [efbedcf0] [f534a228] tg3_chip_reset+0x7cc/0x9f8 [tg3]
> [efbedd20] [f534a8f0] tg3_reset_hw+0x58/0x2360 [tg3]
> [efbedd70] [f5351dd4] tg3_open+0x610/0x910 [tg3]
> [efbeddb0] [c01e1c6c] dev_open+0x100/0x138
> [efbeddd0] [c01dff20] dev_change_flags+0x80/0x1ac
> [efbeddf0] [c02232cc] devinet_ioctl+0x648/0x824
> [efbede60] [c0223de4] inet_ioctl+0xcc/0xf8
> [efbede70] [c01cdf44] sock_ioctl+0x60/0x300
> [efbede90] [c008a35c] vfs_ioctl+0x34/0x8c
> [efbedea0] [c008a580] do_vfs_ioctl+0x88/0x724
> [efbedf10] [c008ac5c] sys_ioctl+0x40/0x74
> [efbedf40] [c000f814] ret_from_syscall+0x0/0x3c
> Instruction dump:
> 0fe00000 4bfffe80 801a000c 5409016f 4182fe60 4bf0f6d9 2f830000 41befe54
> 3d20c035 8009c2c0 2f800000 40befe44 <0fe00000> 4bfffe3c 9421ffe0 7c0802a6
> 
> Does it indicate a real problem, or something that can be ignored ?
> 
> Additional information from kernel log:
> 
> tg3.c:v3.99 (April 20, 2009)
> tg3 0002:05:00.0: enabling bus mastering
> tg3 0002:05:00.0: PME# disabled
> tg3 mdio bus: probed
> eth2: Tigon3 [partno(BCM57760) rev 57780001] (PCI Express) MAC address 
> 00:10:18:00:00:00
> eth2: attached PHY driver [Broadcom BCM57780] (mii_bus:phy_addr=500:01)
> eth2: RXcsums[1] LinkChgREG[0] MIirq[0] ASF[0] TSOcap[1]
> eth2: dma_rwctrl[76180000] dma_mask[64-bit]
> tg3 0002:05:00.0: PME# disabled

Yes, this is a real problem.  The driver is taking the MDIO bus lock
while holding the device's own spinlock.  I think I may have a
workaround.  Let me test it and get back to you.