quoted

Drivers that load firmware from their probe routine have problems with the
latest versions of udev as they get timeouts while waiting for user
space to start. The problem is fixed by loading the firmware and starting
mac80211 from a delayed_work queue. By using this method, most of the
original code is preserved.

Signed-off-by: Larry Finger<redacted>
---
This one is compile-tested only.

Larry
---

Any testing done here?

insmod immediately followed by rmmod causes NULL pointer dereference.
The same always happens on rmmode when the firmware image is absent:

[   52.482696] calling  p54spi_init+0x0/0x30 [p54spi] @ 941
[   52.486053] initcall p54spi_init+0x0/0x30 [p54spi] returned 0 after
3071 usecs
[   53.522430] p54spi spi2.0: request_firmware() failed: -2
[   53.522521] p54spi spi2.0: Failed to read firmware
[   56.337036] Unable to handle kernel NULL pointer dereference at
virtual address 00000044
[   56.337188] pgd = c6c2c000
[   56.337219] [00000044] *pgd=87b07831, *pte=00000000, *ppte=00000000
[   56.337341] Internal error: Oops: 17 [#1] PREEMPT
[   56.337402] Modules linked in: p54spi(-)
[   56.337493] CPU: 0    Not tainted  (3.3.0-rc3-11564-g1465640 #12)
[   56.337585] PC is at drain_workqueue+0x10/0x1b4
[   56.337677] LR is at drain_workqueue+0x10/0x1b4
[   56.337738] pc : [<c0043340>]    lr : [<c0043340>]    psr: 80000013
[   56.337768] sp : c79e3eb8  ip : 00000000  fp : bed7cc1c
[   56.337890] r10: 00000000  r9 : c79e2000  r8 : c0012a48
[   56.337951] r7 : c7863634  r6 : c7863600  r5 : bf00115c  r4 : 00000000
[   56.338043] r3 : 00000000  r2 : 00000000  r1 : c040c844  r0 : 00000001
[   56.338134] Flags: Nzcv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
[   56.338226] Control: 00c5387d  Table: 86c2c000  DAC: 00000015
[   56.338317] Process rmmod (pid: 950, stack limit = 0xc79e2268)
[   56.338378] Stack: (0xc79e3eb8 to 0xc79e4000)
[   56.338470] 3ea0:
    00000000 bf00115c
[   56.338592] 3ec0: c7863600 c7863634 c0012a48 c79e2000 00000000
c00434f0 c7816300 bf00115c
[   56.338714] 3ee0: c7863600 c0278c38 c7816fa0 bf000ba0 c7863600
bf001ff8 bf001ff8 c01aa53c
[   56.338836] 3f00: c01aa524 c0195808 c7863600 c79e2000 bf001ff8
c01958fc bf001ff8 00000000
[   56.338989] 3f20: c03e3d44 bed7cbf8 c0012a48 c0194c88 bf002030
00000000 00000013 c0061dc8
[   56.339111] 3f40: c79cdf20 73343570 b6006970 c008577c ffffffff
c6ca0180 c79cdf20 c0086774
[   56.339233] 3f60: b6f23000 b6f22000 bed7cc1c c01466f0 c6ca01b4
00000000 b6f22000 00ca0180
[   56.339355] 3f80: bf002030 00000880 c79e3f8c 00000000 b6f233ff
00000880 bed7cbf8 bed7ce97
[   56.339508] 3fa0: 00000081 c00128a0 00000880 bed7cbf8 bed7cbf8
00000880 bed7cbec 00000000
[   56.339630] 3fc0: 00000880 bed7cbf8 bed7ce97 00000081 00000001
00000001 00011fe4 bed7cc1c
[   56.339752] 3fe0: 00000880 bed7cbf8 00009004 b6e908bc 60000010
bed7cbf8 00000000 00000000
[   56.339904] [<c0043340>] (drain_workqueue+0x10/0x1b4) from
[<c00434f0>] (destroy_workqueue+0xc/0x150)
[   56.340057] [<c00434f0>] (destroy_workqueue+0xc/0x150) from
[<c0278c38>] (ieee80211_unregister_hw+0xbc/0xe4)
[   56.340209] [<c0278c38>] (ieee80211_unregister_hw+0xbc/0xe4) from
[<bf000ba0>] (p54spi_remove+0x1c/0x58 [p54spi])
[   56.340393] [<bf000ba0>] (p54spi_remove+0x1c/0x58 [p54spi]) from
[<c01aa53c>] (spi_drv_remove+0x18/0x1c)
[   56.340576] [<c01aa53c>] (spi_drv_remove+0x18/0x1c) from
[<c0195808>] (__device_release_driver+0x7c/0xbc)
[   56.340728] [<c0195808>] (__device_release_driver+0x7c/0xbc) from
[<c01958fc>] (driver_detach+0xb4/0xdc)
[   56.340850] [<c01958fc>] (driver_detach+0xb4/0xdc) from
[<c0194c88>] (bus_remove_driver+0x8c/0xb4)
[   56.341003] [<c0194c88>] (bus_remove_driver+0x8c/0xb4) from
[<c0061dc8>] (sys_delete_module+0x1c8/0x234)
[   56.341186] [<c0061dc8>] (sys_delete_module+0x1c8/0x234) from
[<c00128a0>] (ret_fast_syscall+0x0/0x30)
[   56.341308] Code: e92d47f0 e1a04000 e3a00001 eb002dbb (e5943044)
[   56.341552] ---[ end trace 79a2a071aae86862 ]---
[   56.341644] note: rmmod[950] exited with preempt_count 1

-- 
Thanks.
-- Max