Btw, I've been working on [1] cleaning up the one-off deferred probe
solution that we have for amba devices. That causes a bunch of other
headaches. Your patch 3/3 takes us further in the wrong direction by
adding more reasons for delaying the addition of the device.
Hi Saravana, I try the link[1], but with it, there is a crash when boot
(qemu-system-arm -M vexpress-a15),
without it, boot successfully.
[ 2.246057] aaci-pl041 1c040000.aaci: ARM AC'97 Interface PL041 rev0
at 0x1c040000, irq 36
[ 2.246357] aaci-pl041 1c040000.aaci: FIFO 512 entries
[ 2.248617] NET: Registered PF_PACKET protocol family
[ 2.250481] 9pnet: Installing 9P2000 support
[ 2.251474] Registering SWP/SWPB emulation handler
[ 2.284374] 1c090000.serial: ttyAMA0 at MMIO 0x1c090000 (irq = 41,
base_baud = 0) is a PL011 rev1
[ 2.287797] printk: console [ttyAMA0] enabled
[ 2.287797] printk: console [ttyAMA0] enabled
[ 2.288262] input: AT Raw Set 2 keyboard as
/devices/platform/bus@8000000/bus@8000000:motherboard-bus/bus@8000000:motherboard-bus:iofpga-bus@300000000/1c060000.kmi/serio0/input/input0
[ 2.288262] input: AT Raw Set 2 keyboard as
/devices/platform/bus@8000000/bus@8000000:motherboard-bus/bus@8000000:motherboard-bus:iofpga-bus@300000000/1c060000.kmi/serio0/input/input0
[ 2.288755] printk: bootconsole [earlycon0] disabled
[ 2.288755] printk: bootconsole [earlycon0] disabled
[ 2.294507] 1c0a0000.serial: ttyAMA1 at MMIO 0x1c0a0000 (irq = 42,
base_baud = 0) is a PL011 rev1
[ 2.296950] 1c0b0000.serial: ttyAMA2 at MMIO 0x1c0b0000 (irq = 43,
base_baud = 0) is a PL011 rev1
[ 2.298636] 1c0c0000.serial: ttyAMA3 at MMIO 0x1c0c0000 (irq = 44,
base_baud = 0) is a PL011 rev1
[ 2.300496] 8<--- cut here ---
[ 2.300775] ------------[ cut here ]------------
[ 2.301260] Unable to handle kernel NULL pointer dereference at
virtual address 00000000
[ 2.300928] WARNING: CPU: 1 PID: 27 at
/home/wkf/work/hulk/lib/refcount.c:25 refcount_warn_saturate+0x108/0x174
[ 2.301700] pgd = (ptrval)
[ 2.302002] refcount_t: addition on 0; use-after-free.
[ 2.302184] [00000000] *pgd=00000000
[ 2.302363] Modules linked in:
[ 2.302384]
[ 2.302753]
[ 2.303501] CPU: 1 PID: 27 Comm: kworker/u4:1 Not tainted 5.14.0-rc7+
#193
[ 2.303990] Hardware name: ARM-Versatile Express
[ 2.304198] Internal error: Oops: 5 [#1] SMP ARM
[ 2.304537] Workqueue: events_unbound deferred_probe_work_func
[ 2.304829] Modules linked in:
[ 2.304865]
[ 2.305133]
[ 2.305401] Backtrace:
[ 2.305562] CPU: 0 PID: 41 Comm: kworker/0:2 Not tainted 5.14.0-rc7+ #193
[ 2.305614] Hardware name: ARM-Versatile Express
[ 2.305576]
[ 2.305781] [<c010c780>] (dump_backtrace) from [<c010cacc>]
(show_stack+0x20/0x24)
[ 2.306266] Workqueue: events_long serio_handle_event
[ 2.306732] r7:00000009 r6:00000000 r5:c0b1efb8 r4:600b0093
[ 2.306889] PC is at strcmp+0x18/0x44
[ 2.307115] [<c010caac>] (show_stack) from [<c091eba4>]
(dump_stack_lvl+0x48/0x54)
[ 2.307263] LR is at platform_match+0xb8/0xcc
[ 2.307498] [<c091eb5c>] (dump_stack_lvl) from [<c091ebc8>]
(dump_stack+0x18/0x1c)
[ 2.307739] pc : [<c0560aec>] lr : [<c064626c>] psr: 60000013
[ 2.307988] r5:c0b4ef98 r4:c165ddc4
[ 2.308317] sp : c1675d70 ip : c1675d80 fp : c1675d7c
[ 2.308433] [<c091ebb0>] (dump_stack) from [<c01289c4>]
(__warn+0x110/0x114)
[ 2.308743] r10: 00000000 r9 : 00000000 r8 : 00000001
[ 2.308961] [<c01288b4>] (__warn) from [<c0128a4c>]
(warn_slowpath_fmt+0x84/0xc0)
[ 2.309252] r7 : c0d04d08 r6 : c13aed18 r5 : c1090fc0 r4 : c13aed18
[ 2.309547] r9:00000009 r8:c0504f10 r7:00000019 r6:c0b4ef98
r5:c0b4efbc r4:c0d04d08
[ 2.309975] [<c01289cc>] (warn_slowpath_fmt) from [<c0504f10>]
(refcount_warn_saturate+0x108/0x174)
[ 2.310531] r3 : c0a5e1c0 r2 : 00000002 r1 : c0b82860 r0 : 00000000
[ 2.311263] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM
Segment none
[ 2.311298] r9:600b0013 r8:00000000 r7:00000000 r6:c1787eb8
r5:c165de3c r4:c1702b38
[ 2.311899] Control: 10c5387d Table: 8000406a DAC: 00000051
[ 2.312117] [<c0504e08>] (refcount_warn_saturate) from [<c055657c>]
(klist_next+0x134/0x138)
[ 2.312755] Register r0 information:
[ 2.312964] [<c0556448>] (klist_next) from [<c06411dc>]
(bus_for_each_drv+0x74/0xc8)
[ 2.313345] NULL pointer
[ 2.313690] Register r1 information:
[ 2.313736] r9:00000000 r8:00000001 r7:c0d04d08 r6:c064373c
r5:c165de6c r4:00000000
[ 2.313933] non-slab/vmalloc memory
[ 2.314172] [<c0641168>] (bus_for_each_drv) from [<c0642f38>]
(__device_attach+0xf0/0x15c)
[ 2.315042] r7:c10846b8 r6:c13ae444 r5:c13ae400 r4:c0d04d08
[ 2.315060] Register r2 information:
[ 2.315243] [<c0642e48>] (__device_attach) from [<c064390c>]
(device_initial_probe+0x1c/0x20)
[ 2.315276] non-paged memory
[ 2.315569] r8:00000000 r7:c10846b8 r6:c13ae400 r5:c107d690 r4:c13ae400
[ 2.315593] [<c06438f0>] (device_initial_probe) from [<c0642080>]
(bus_probe_device+0x94/0x9c)
[ 2.316192] [<c0641fec>] (bus_probe_device) from [<c064259c>]
(deferred_probe_work_func+0x8c/0xb8)
[ 2.316939] r7:c10846b8 r6:c10846a4 r5:c10846a4 r4:c13ae400
[ 2.317573] [<c0642510>] (deferred_probe_work_func) from [<c01475a4>]
(process_one_work+0x238/0x594)
[ 2.318513] r9:00000000 r8:00000000 r7:c1225b00 r6:c1206200
r5:c16b6f80 r4:c10846d4
[ 2.318931] Register r3 information: non-slab/vmalloc memory
[ 2.319218] [<c014736c>] (process_one_work) from [<c0147bc4>]
(worker_thread+0x2c4/0x5f4)
[ 2.320001] r10:c0d03d00 r9:00000088 r8:ffffe000 r7:c1206218
r6:c16b6f94 r5:c1206200
[ 2.320280] Register r4 information:
[ 2.320614] r4:c16b6f80
[ 2.320942] [<c0147900>] (worker_thread) from [<c014feb4>]
(kthread+0x178/0x194)
[ 2.321111] slab kmalloc-1k
[ 2.321403] r10:c165c000 r9:c1313e74 r8:00000000 r7:c16b6f80
r6:c0147900 r5:c16b5580
[ 2.321391] start c13aec00 pointer offset 280
[ 2.321993] r4:c13d4980
[ 2.322006] size 1024
[ 2.322176] [<c014fd3c>] (kthread) from [<c0100150>]
(ret_from_fork+0x14/0x24)
[ 2.323165] Exception stack(0xc165dfb0 to 0xc165dff8)
[ 2.323187]
[ 2.323371] Register r5 information: non-slab/vmalloc memory
[ 2.323535] Register r6 information: slab kmalloc-1k start c13aec00
pointer offset 280 size 1024
[ 2.324594] Register r7 information:
[ 2.324597] dfa0: 00000000
00000000 00000000 00000000
[ 2.325507] non-slab/vmalloc memory
[ 2.325830] Register r8 information: non-paged memory
[ 2.326267] Register r9 information:
[ 2.326274] dfc0: 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000
[ 2.326453] NULL pointer
[ 2.326942] Register r10 information: NULL pointer
[ 2.327159] dfe0: 00000000 00000000 00000000 00000000 00000013 00000000
[ 2.327258] Register r11 information: non-slab/vmalloc memory
[ 2.327904] Register r12 information:
[ 2.327928] r10:00000000 r9:00000000 r8:00000000 r7:00000000
r6:00000000 r5:c014fd3c
[ 2.327937] non-slab/vmalloc memory
[ 2.328057] Process kworker/0:2 (pid: 41, stack limit = 0x(ptrval))
[ 2.328204] Stack: (0xc1675d70 to 0xc1676000)
[ 2.328479] r4:c16b5580
[ 2.329851] ---[ end trace f293b13f591ee203 ]---
[ 2.330027] 5d60: c1675d9c
c1675d80 c064626c c0560ae0
[ 2.331070] 5d80: c1090fc0 c1675df4 c13aed18 c0d04d08 c1675dbc
c1675da0 c0643778 c06461c0
[ 2.331120] 8<--- cut here ---
[ 2.331739] Unhandled fault: page domain fault (0x01b) at 0x00000010
[ 2.331915] 5da0: 00000000 c1675df4 c064373c c0d04d08 c1675dec
c1675dc0 c06411d0 c0643748
[ 2.332379] pgd = (ptrval)
[ 2.332408] 5dc0: c1675dec c16bf06c c1787eb8 76076098 c0d04d08
c13aed18 c13aed5c c13aa800
[ 2.332889] [00000010] *pgd=00000000
[ 2.332951] 5de0: c1675e24 c1675df0 c0642f38 c0641174 c1675e44
c13aed18 00000001 76076098
[ 2.333535] 5e00: 00000000 c13aed18 c108ea84 c13aed18 c13aa800
c10843a0 c1675e34 c1675e28
[ 2.334201] 5e20: c064390c c0642e54 c1675e54 c1675e38 c0642080
c06438fc c13aed18 00000000
[ 2.334845] 5e40: c0d04d08 c13aa800 c1675eb4 c1675e58 c063fa1c
c0641ff8 c13a5180 c1706380
[ 2.335464] 5e60: eee2e0c0 c1201180 c071c008 c11ea558 c0b7f260
c0b7f28c c1675eb4 c1675e88
[ 2.336088] 5e80: c02e6368 76076098 00000001 c1706f4c c13aec00
c108ea54 c1706f40 c11ea558
[ 2.336758] 5ea0: c0b7f260 c0b7f28c c1675ef4 c1675eb8 c071c0e4
c063f620 c0923300 c0158300
[ 2.337399] 5ec0: 00000000 c13aed18 c1675ef4 c108ea70 c1702e80
effc4400 effc7700 00000000
[ 2.338025] 5ee0: 00000000 c10b2580 c1675f34 c1675ef8 c01475a4
c071bf38 c13a5100 ffffe000
[ 2.338663] 5f00: c1675f1c c1675f10 c0149250 c1702e80 effc4400
c1702e94 effc4418 ffffe000
[ 2.339296] 5f20: 00000008 c0d03d00 c1675f74 c1675f38 c014795c
c0147378 c130fe74 c0b0c2c4
[ 2.340102] 5f40: c10b1d2a effc4400 c1675f74 c1706000 c1706880
c0147900 c1702e80 00000000
[ 2.340736] 5f60: c130fe74 c1674000 c1675fac c1675f78 c014feb4
c014790c c1706024 c1706024
[ 2.341315] 5f80: c1675fac c1706880 c014fd3c 00000000 00000000
00000000 00000000 00000000
[ 2.341852] 5fa0: 00000000 c1675fb0 c0100150 c014fd48 00000000
00000000 00000000 00000000
[ 2.342407] 5fc0: 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000
[ 2.342957] 5fe0: 00000000 00000000 00000000 00000000 00000013
00000000 00000000 00000000
[ 2.343361] Backtrace:
[ 2.343573] [<c0560ad4>] (strcmp) from [<c064626c>]
(platform_match+0xb8/0xcc)
[ 2.343954] [<c06461b4>] (platform_match) from [<c0643778>]
(__device_attach_driver+0x3c/0xc4)
[ 2.344369] r7:c0d04d08 r6:c13aed18 r5:c1675df4 r4:c1090fc0
[ 2.344615] [<c064373c>] (__device_attach_driver) from [<c06411d0>]
(bus_for_each_drv+0x68/0xc8)
[ 2.345015] r7:c0d04d08 r6:c064373c r5:c1675df4 r4:00000000
[ 2.345283] [<c0641168>] (bus_for_each_drv) from [<c0642f38>]
(__device_attach+0xf0/0x15c)
[ 2.345654] r7:c13aa800 r6:c13aed5c r5:c13aed18 r4:c0d04d08
[ 2.345903] [<c0642e48>] (__device_attach) from [<c064390c>]
(device_initial_probe+0x1c/0x20)
[ 2.346325] r8:c10843a0 r7:c13aa800 r6:c13aed18 r5:c108ea84 r4:c13aed18
[ 2.346635] [<c06438f0>] (device_initial_probe) from [<c0642080>]
(bus_probe_device+0x94/0x9c)
[ 2.347038] [<c0641fec>] (bus_probe_device) from [<c063fa1c>]
(device_add+0x408/0x8b8)
[ 2.347419] r7:c13aa800 r6:c0d04d08 r5:00000000 r4:c13aed18
[ 2.347695] [<c063f614>] (device_add) from [<c071c0e4>]
(serio_handle_event+0x1b8/0x234)
[ 2.348094] r10:c0b7f28c r9:c0b7f260 r8:c11ea558 r7:c1706f40
r6:c108ea54 r5:c13aec00
[ 2.348453] r4:c1706f4c
[ 2.348604] [<c071bf2c>] (serio_handle_event) from [<c01475a4>]
(process_one_work+0x238/0x594)
[ 2.348968] r10:c10b2580 r9:00000000 r8:00000000 r7:effc7700
r6:effc4400 r5:c1702e80
[ 2.349315] r4:c108ea70
[ 2.349468] [<c014736c>] (process_one_work) from [<c014795c>]
(worker_thread+0x5c/0x5f4)
[ 2.349875] r10:c0d03d00 r9:00000008 r8:ffffe000 r7:effc4418
r6:c1702e94 r5:effc4400
[ 2.350169] r4:c1702e80
[ 2.350315] [<c0147900>] (worker_thread) from [<c014feb4>]
(kthread+0x178/0x194)
[ 2.350687] r10:c1674000 r9:c130fe74 r8:00000000 r7:c1702e80
r6:c0147900 r5:c1706880
[ 2.351038] r4:c1706000
[ 2.351182] [<c014fd3c>] (kthread) from [<c0100150>]
(ret_from_fork+0x14/0x24)
[ 2.351500] Exception stack(0xc1675fb0 to 0xc1675ff8)
[ 2.351855] 5fa0: 00000000
00000000 00000000 00000000
[ 2.352415] 5fc0: 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000
[ 2.352923] 5fe0: 00000000 00000000 00000000 00000000 00000013 00000000
[ 2.353283] r10:00000000 r9:00000000 r8:00000000 r7:00000000
r6:00000000 r5:c014fd3c
[ 2.353618] r4:c1706880
[ 2.354146] Code: e24cb004 ea000001 e3530000 0a000006 (e4d03001)
[ 2.354860] Internal error: : 1b [#2] SMP ARM
[ 2.355172] Modules linked in:
[ 2.355254] ---[ end trace f293b13f591ee204 ]---
[ 2.355650] CPU: 1 PID: 27 Comm: kworker/u4:1 Tainted: G D
W 5.14.0-rc7+ #193
[ 2.355888] Kernel panic - not syncing: Fatal exception
[ 2.355990] Hardware name: ARM-Versatile Express
[ 2.356735] Workqueue: events_unbound deferred_probe_work_func
[ 2.357217] PC is at klist_put+0x20/0xa4
[ 2.357537] LR is at klist_iter_exit+0x24/0x30
[ 2.357872] pc : [<c0556280>] lr : [<c0556340>] psr: a00b0013
[ 2.358299] sp : c165de00 ip : c165de20 fp : c165de1c
[ 2.358655] r10: c10b2580 r9 : 00000000 r8 : 00000001
[ 2.359009] r7 : c1702b38 r6 : 00000000 r5 : c165de6c r4 : 00000000
[ 2.359440] r3 : 00000000 r2 : 76076098 r1 : 00000000 r0 : 00000000
[ 2.359893] Flags: NzCv IRQs on FIQs on Mode SVC_32 ISA ARM
Segment none
[ 2.360368] Control: 10c5387d Table: 8177806a DAC: 00000051
[ 2.360759] Register r0 information: NULL pointer
[ 2.361126] Register r1 information: NULL pointer
[ 2.361477] Register r2 information: non-paged memory
[ 2.361835] Register r3 information: NULL pointer
[ 2.362162] Register r4 information: NULL pointer
[ 2.362486] Register r5 information: non-slab/vmalloc memory
[ 2.362887] Register r6 information: NULL pointer
[ 2.363226] Register r7 information: slab kmalloc-128 start c1702b00
pointer offset 56 size 128
[ 2.363919] Register r8 information: non-paged memory
[ 2.364299] Register r9 information: NULL pointer
[ 2.364668] Register r10 information: non-slab/vmalloc memory
[ 2.365089] Register r11 information: non-slab/vmalloc memory
[ 2.365466] Register r12 information: non-slab/vmalloc memory
[ 2.365872] Process kworker/u4:1 (pid: 27, stack limit = 0x(ptrval))
[ 2.366297] Stack: (0xc165de00 to 0xc165e000)
[ 2.366769] de00: c165de3c c165de6c c064373c c0d04d08 c165de34
c165de20 c0556340 c055626c
[ 2.367478] de20: 00000000 c165de6c c165de64 c165de38 c0641208
c0556328 c165de64 c136996c
[ 2.368192] de40: c1702b38 76076098 c0d04d08 c13ae400 c13ae444
c10846b8 c165de9c c165de68
[ 2.368934] de60: c0642f38 c0641174 c063c4c4 c13ae400 00000001
76076098 00000000 c13ae400
[ 2.369654] de80: c107d690 c13ae400 c10846b8 00000000 c165deac
c165dea0 c064390c c0642e54
[ 2.370367] dea0: c165decc c165deb0 c0642080 c06438fc c13ae400
c10846a4 c10846a4 c10846b8
[ 2.371046] dec0: c165def4 c165ded0 c064259c c0641ff8 c10846d4
c16b6f80 c1206200 c1225b00
[ 2.371774] dee0: 00000000 00000000 c165df34 c165def8 c01475a4
c064251c c13906c0 ffffe000
[ 2.372470] df00: c165df1c c165df10 c0149250 c16b6f80 c1206200
c16b6f94 c1206218 ffffe000
[ 2.373189] df20: 00000088 c0d03d00 c165df74 c165df38 c0147bc4
c0147378 c1313e74 c0b0c2c4
[ 2.373925] df40: c10b1d2a c1206200 c165df74 c13d4980 c16b5580
c0147900 c16b6f80 00000000
[ 2.374628] df60: c1313e74 c165c000 c165dfac c165df78 c014feb4
c014790c c13d49a4 c13d49a4
[ 2.375345] df80: c165dfac c16b5580 c014fd3c 00000000 00000000
00000000 00000000 00000000
[ 2.376080] dfa0: 00000000 c165dfb0 c0100150 c014fd48 00000000
00000000 00000000 00000000
[ 2.376807] dfc0: 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000
[ 2.377534] dfe0: 00000000 00000000 00000000 00000000 00000013
00000000 00000000 00000000
[ 2.378080] Backtrace:
[ 2.378297] [<c0556260>] (klist_put) from [<c0556340>]
(klist_iter_exit+0x24/0x30)
[ 2.378819] r7:c0d04d08 r6:c064373c r5:c165de6c r4:c165de3c
[ 2.379199] [<c055631c>] (klist_iter_exit) from [<c0641208>]
(bus_for_each_drv+0xa0/0xc8)
[ 2.379701] r5:c165de6c r4:00000000
[ 2.379932] [<c0641168>] (bus_for_each_drv) from [<c0642f38>]
(__device_attach+0xf0/0x15c)
[ 2.380482] r7:c10846b8 r6:c13ae444 r5:c13ae400 r4:c0d04d08
[ 2.380871] [<c0642e48>] (__device_attach) from [<c064390c>]
(device_initial_probe+0x1c/0x20)
[ 2.381453] r8:00000000 r7:c10846b8 r6:c13ae400 r5:c107d690 r4:c13ae400
[ 2.381851] [<c06438f0>] (device_initial_probe) from [<c0642080>]
(bus_probe_device+0x94/0x9c)
[ 2.382364] [<c0641fec>] (bus_probe_device) from [<c064259c>]
(deferred_probe_work_func+0x8c/0xb8)
[ 2.382936] r7:c10846b8 r6:c10846a4 r5:c10846a4 r4:c13ae400
[ 2.383266] [<c0642510>] (deferred_probe_work_func) from [<c01475a4>]
(process_one_work+0x238/0x594)
[ 2.383885] r9:00000000 r8:00000000 r7:c1225b00 r6:c1206200
r5:c16b6f80 r4:c10846d4
[ 2.384344] [<c014736c>] (process_one_work) from [<c0147bc4>]
(worker_thread+0x2c4/0x5f4)
[ 2.384893] r10:c0d03d00 r9:00000088 r8:ffffe000 r7:c1206218
r6:c16b6f94 r5:c1206200
[ 2.385341] r4:c16b6f80
[ 2.385536] [<c0147900>] (worker_thread) from [<c014feb4>]
(kthread+0x178/0x194)
[ 2.386030] r10:c165c000 r9:c1313e74 r8:00000000 r7:c16b6f80
r6:c0147900 r5:c16b5580
[ 2.386540] r4:c13d4980
[ 2.386742] [<c014fd3c>] (kthread) from [<c0100150>]
(ret_from_fork+0x14/0x24)
[ 2.387211] Exception stack(0xc165dfb0 to 0xc165dff8)
[ 2.387653] dfa0: 00000000
00000000 00000000 00000000
[ 2.388374] dfc0: 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000
[ 2.389071] dfe0: 00000000 00000000 00000000 00000000 00000013 00000000
[ 2.389546] r10:00000000 r9:00000000 r8:00000000 r7:00000000
r6:00000000 r5:c014fd3c
[ 2.390037] r4:c16b5580
[ 2.390376] Code: e1a07000 e1a06001 e3c44001 e1a00004 (e5945010)
[ 2.390836] ---[ end trace f293b13f591ee205 ]---
[ 2.391580] ---[ end Kernel panic - not syncing: Fatal exception ]---
-Saravana
[1] - https://lore.kernel.org/lkml/CAGETcx8b228nDUho3cX9AAQ-pXOfZTMv8cj2vhdx9yc_pk8q+A@xxxxxxxxxxxxxx/
.
.
