ath6kl: Fix kernel panic while receiving fwlog during boot
authorVasanthakumar Thiagarajan <vthiagar@qca.qualcomm.com>
Tue, 6 Mar 2012 09:09:40 +0000 (14:39 +0530)
committerKalle Valo <kvalo@qca.qualcomm.com>
Tue, 6 Mar 2012 15:53:54 +0000 (17:53 +0200)
commit068a4633bf42501db3ec934beff07cd50c1b7e9d
treece9f87c4caa333517d2c77d7b0c3a85dbe820c2d
parent05e5bd0f3daddb0368a433af5b58be68c62dc365
ath6kl: Fix kernel panic while receiving fwlog during boot

"ath6kl: Defer wiphy and netdev registration till the end of ath6kl_core_init()"
causes kernel panic by accessing the unallocated debug resources during
boot time. To fix this, split the debug initialization funtion into two,
one initializes the debug resource and the other takes care of debugfs
initialization. When this issue shows up the kernel crash dump would
look like

 ath6kl_debug_fwlog_event+0x9c/0x10a
 [<c10666c9>] register_lock_class+0x57/0x288
 [<c1065cd3>] ? trace_hardirqs_on+0xb/0xd
 [<f801f4c9>] ? ath6kl_debug_fwlog_event+0x9c/0x10a
 [<c1066a8a>] __lock_acquire+0x96/0xbe5
 [<c106007b>] ? alarmtimer_suspend+0x80/0x127
 [<c10258da>] ? vprintk+0x394/0x3b1
 [<f801f4c9>] ? ath6kl_debug_fwlog_event+0x9c/0x10a
 [<c10676b3>] lock_acquire+0xda/0xf9
 [<f801f4c9>] ? ath6kl_debug_fwlog_event+0x9c/0x10a
 [<c1532ce3>] _raw_spin_lock+0x28/0x58
 [<f801f4c9>] ? ath6kl_debug_fwlog_event+0x9c/0x10a
 [<f801f4c9>] ath6kl_debug_fwlog_event+0x9c/0x10a
 [<f80310a4>] ath6kl_wmi_control_rx+0x69d/0xb50 [ath6kl_core]
 [<f802d2e1>] ? ath6kl_rx+0x3c/0x839 [ath6kl_core]
 [<f802d35d>] ath6kl_rx+0xb8/0x839 [ath6kl_core]
 [<c104b81e>] ? local_clock+0x2d/0x4e
 [<c102a0af>] ? _local_bh_enable_ip+0x94/0x98
 [<f802bfc0>] ? ath6kl_alloc_amsdu_rxbuf+0xb7/0xb7
 [<f8023b28>] ath6kl_htc_rxmsg_pending_handler+0x891/0x988 [ath6kl_core]
 [<f802bf00>] ? ath6kl_refill_amsdu_rxbufs+0x89/0x92
 [<f802d2a5>] ? aggr_timeout+0xed/0xed [ath6kl_core]
 [<f802bfc0>] ? ath6kl_alloc_amsdu_rxbuf+0xb7/0xb7
 [<f802c420>] ? ath6kl_tx_complete+0x376/0x376 [ath6kl_core]
 [<f8020e92>] ath6kl_hif_intr_bh_handler+0xf7/0x33e
 [<c138ab00>] ? mmc_host_disable+0x15/0x3a
 [<f8123b5c>] ath6kl_sdio_irq_handler+0x3c/0x90 [ath6kl_sdio]
 [<c1392f56>] sdio_irq_thread+0xb6/0x29c
 [<c1392ea0>] ? sdio_claim_irq+0x1cb/0x1cb
 [<c103d4c0>] kthread+0x67/0x6c
 [<c103d459>] ? __init_kthread_worker+0x42/0x42
 [<c153903a>] kernel_thread_helper+0x6/0xd
 BUG: unable to handle kernel NULL pointer dereference at
EIP: [<f801f4d4>] ath6kl_debug_fwlog_event+0xa7/0x10a

kvalo: rename new function to ath6kl_debug_init_fs() and add a comment
why it's needed

Reported-by: Kalle Valo <kvalo@qca.qualcomm.com>
Signed-off-by: Vasanthakumar Thiagarajan <vthiagar@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
drivers/net/wireless/ath/ath6kl/core.c
drivers/net/wireless/ath/ath6kl/debug.c
drivers/net/wireless/ath/ath6kl/debug.h