4.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Aditya Shankar <Aditya.Shankar@xxxxxxxxxxxxx> commit 1d4f1d53e1e2d5e38f4d3ca3bf60f8be5025540f upstream. Commit 2518ac59eb27 ("staging: wilc1000: Replace kthread with workqueue for host interface") adds an unconditional destroy_workqueue() on the wilc's "hif_workqueue" soon after its creation thereby rendering it unusable. It then further attempts to queue work onto this non-existing hif_worqueue and results in: Unable to handle kernel NULL pointer dereference at virtual address 00000010 pgd = de478000 [00000010] *pgd=3eec0831, *pte=00000000, *ppte=00000000 Internal error: Oops: 17 [#1] ARM Modules linked in: wilc1000_sdio(C) wilc1000(C) CPU: 0 PID: 825 Comm: ifconfig Tainted: G C 4.8.0-rc8+ #37 Hardware name: Atmel SAMA5 task: df56f800 task.stack: deeb0000 PC is at __queue_work+0x90/0x284 LR is at __queue_work+0x58/0x284 pc : [<c0126bb0>] lr : [<c0126b78>] psr: 600f0093 sp : deeb1aa0 ip : def22d78 fp : deea6000 r10: 00000000 r9 : c0a08150 r8 : c0a2f058 r7 : 00000001 r6 : dee9b600 r5 : def22d74 r4 : 00000000 r3 : 00000000 r2 : def22d74 r1 : 07ffffff r0 : 00000000 Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment none ... [<c0127060>] (__queue_work) from [<c0127298>] (queue_work_on+0x34/0x40) [<c0127298>] (queue_work_on) from [<bf0076b4>] (wilc_enqueue_cmd+0x54/0x64 [wilc1000]) [<bf0076b4>] (wilc_enqueue_cmd [wilc1000]) from [<bf0082b4>] (wilc_set_wfi_drv_handler+0x48/0x70 [wilc1000]) [<bf0082b4>] (wilc_set_wfi_drv_handler [wilc1000]) from [<bf00509c>] (wilc_mac_open+0x214/0x250 [wilc1000]) [<bf00509c>] (wilc_mac_open [wilc1000]) from [<c04fde98>] (__dev_open+0xb8/0x11c) [<c04fde98>] (__dev_open) from [<c04fe128>] (__dev_change_flags+0x94/0x158) [<c04fe128>] (__dev_change_flags) from [<c04fe204>] (dev_change_flags+0x18/0x48) [<c04fe204>] (dev_change_flags) from [<c0557d5c>] (devinet_ioctl+0x6b4/0x788) [<c0557d5c>] (devinet_ioctl) from [<c04e40a0>] (sock_ioctl+0x154/0x2cc) [<c04e40a0>] (sock_ioctl) from [<c01b16e0>] (do_vfs_ioctl+0x9c/0x878) [<c01b16e0>] (do_vfs_ioctl) from [<c01b1ef0>] (SyS_ioctl+0x34/0x5c) [<c01b1ef0>] (SyS_ioctl) from [<c0107520>] (ret_fast_syscall+0x0/0x3c) Code: e5932004 e1520006 01a04003 0affffff (e5943010) ---[ end trace b612328adaa6bf20 ]--- This fix removes the unnecessary call to destroy_workqueue() while opening the device to avoid the above kernel panic. The deinit routine already does a good job of terminating the workqueue when no longer needed. Reported-by: Nicolas Ferre <Nicolas.Ferre@xxxxxxxxxxxxx> Fixes: 2518ac59eb27 ("staging: wilc1000: Replace kthread with workqueue for host interface") Signed-off-by: Aditya Shankar <Aditya.Shankar@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/staging/wilc1000/host_interface.c | 1 - 1 file changed, 1 deletion(-) --- a/drivers/staging/wilc1000/host_interface.c +++ b/drivers/staging/wilc1000/host_interface.c @@ -3391,7 +3391,6 @@ int wilc_init(struct net_device *dev, st clients_count++; - destroy_workqueue(hif_workqueue); _fail_: return result; } -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html