Hi Uwe,
Sorry for my late reply.
I only get the initialization line:
************** at91rm9200_timer_init: shift=32, mult=140737,
min_delta_ns=61036, minclc=2
I have attached the kernel panic.
Best regards,
Bo
Uwe Kleine-König wrote:
Hello,
On Fri, Aug 21, 2009 at 02:57:43PM +0200, Bo Hansen wrote:
Hi Uwe,
I cannot find anything in the dmesg or serial output regarding the
WARN_ON_ONCE(...)
I guess the WARN_ON_ONCE(...) should show up in dmesg output?
What puzzles me is that I tried the CONFIG_DEBUG_BUGVERBOSE=y
also when I enabled CONFIG_DEBUG_INFO. When I do
this I don't get the kernel panic. Is this somehow related to the
WARN_ON_ONCE?
Attachments only sent to Uwe - anybody are welcome to get a copy.
Hhhhmm, clkevt32k_next_event is called with delta=1 which hits
BUG_ON(delta < 2).
I calculated the clockeventdevice parameters by hand, and the numbers
look good:
clkevt.shift = 32
clkevt.mult = div_sc(AT91_SLOW_CLOCK, NSEC_PER_SEC, clkevt.shift)
= (32768 << 32) / 1000000000
= 140737
clkevt.min_delta_ns = clockevent_delta2ns(2, &clkevt) + 1
= (2 << clkevt.shift) / clkevt.mult + 1
= (2 << 32) / 140737 + 1
= 61036
min_delta = (clkevt.min_delta_ns * mult) >> clkevt.shift
= (61036 * 140737) >> 32
= 2
Can you please apply the patch below, reproduce and provide the two
lines of output resulting from the two added printks?
Best regards
Uwe
diff --git a/arch/arm/mach-at91/at91rm9200_time.c b/arch/arm/mach-at91/at91rm9200_time.c
index 1ff1bda..83a7379 100644
--- a/arch/arm/mach-at91/at91rm9200_time.c
+++ b/arch/arm/mach-at91/at91rm9200_time.c
@@ -136,7 +136,13 @@ clkevt32k_next_event(unsigned long delta, struct clock_event_device *dev)
u32 alm;
int status = 0;
- BUG_ON(delta < 2);
+ if (unlikely(delta < 2)) {
+ pr_emerg("************** %s: shift=%d, mult=%lu, "
+ "min_delta_ns=%lu, dev=%pS\n", __func__,
+ dev->shift, dev->mult,
+ dev->min_delta_ns, dev);
+ BUG();
+ }
/* Use "raw" primitives so we behave correctly on RT kernels. */
raw_local_irq_save(flags);
@@ -205,6 +211,18 @@ void __init at91rm9200_timer_init(void)
clkevt.mult = div_sc(AT91_SLOW_CLOCK, NSEC_PER_SEC, clkevt.shift);
clkevt.max_delta_ns = clockevent_delta2ns(AT91_ST_ALMV, &clkevt);
clkevt.min_delta_ns = clockevent_delta2ns(2, &clkevt) + 1;
+
+ {
+ unsigned long long clc = (int64_t)clkevt.min_delta_ns *
+ clkevt.mult;
+
+ clc >>= clkevt.shift;
+
+ pr_info("************** %s: shift=%d, mult=%lu, "
+ "min_delta_ns=%lu, minclc=%llu\n", __func__,
+ clkevt.shift, clkevt.mult,
+ clkevt.min_delta_ns, clc);
+ }
clkevt.cpumask = cpumask_of(0);
clockevents_register_device(&clkevt);
Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = c3930000
[00000000] *pgd=2386e031, *pte=00000000, *ppte=00000000
Internal error: Oops: 817 [#1] PREEMPT
Modules linked in:
CPU: 0 Not tainted (2.6.29.6-rt23 #1)
PC is at clkevt32k_next_event+0x94/0xd8
LR is at rt_mutex_unlock+0x10/0x14
pc : [<c002efac>] lr : [<c0256e40>] psr: 00000093
sp : c3a6fc20 ip : c3a6fb30 fp : c3a6fc44
r10: 00000001 r9 : 00000000 r8 : c02f6a30
r7 : 00000032 r6 : 00000000 r5 : 00000001 r4 : 00000000
r3 : 00000000 r2 : 00010002 r1 : 60000093 r0 : 00000062
Flags: nzcv IRQs off FIQs on Mode SVC_32 ISA ARM Segment user
Control: c000717f Table: 23930000 DAC: 00000015
Process cyclictest (pid: 579, stack limit = 0xc3a6e270)
Stack: (0xc3a6fc20 to 0xc3a70000)
fc20: 0000dcaa c02f6a30 00013bc9 00000000 000225c1 00000000 c3a6fc6c c3a6fc48
fc40: c005a20c c002ef28 00000000 0083ad27 00000032 0082d07d 00000032 c02f6a30
fc60: c3a6fcbc c3a6fc70 c005aed4 c005a120 0082d07d 00000032 0083ad27 00000032
fc80: 0082d07d 00000032 0082bdb6 00000032 3bccb551 00829826 00000032 00000032
fca0: c02f9de0 00829826 00000032 c3a6e000 c3a6fcdc c3a6fcc0 c005af78 c005ae18
fcc0: 00000001 00000000 c02f9de0 0082947f c3a6fd3c c3a6fce0 c0052188 c005af58
fce0: 3fd06258 c02f6a30 0082947f 00000032 c3a6fd1c c02f9de0 00000001 00000000
fd00: 0082947f 00000032 c02f9de0 198461bc c3a6fd7c c02f6a08 00010002 c3a6e000
fd20: 00000001 00000000 00000000 00000001 c3a6fd5c c3a6fd40 c002f0a4 c0051f54
fd40: 198461bc c02f6a08 00010002 c3a6e000 c3a6fd8c c3a6fd60 c0065168 c002f000
fd60: 00000001 c02fa4f8 c3a6e000 c02f6a08 00000001 00000001 c3a6e000 c3a6e000
fd80: c3a6fdac c3a6fd90 c0067908 c0065124 00000001 c0302d40 00000000 00000002
fda0: c3a6fdcc c3a6fdb0 c002506c c0067814 00000000 ffffffff fefff000 00000001
fdc0: c3a6fe74 c3a6fdd0 c00259dc c0025010 00000000 c3a67ef8 c3a5fef8 40000013
fde0: 40000013 00000000 0233a240 00000032 c3a6fef8 c02f9de0 c3a6e000 c3a6fe74
fe00: c3a67ef8 c3a6fe18 c3a47ef8 c00528a4 60000013 ffffffff 00000000 00000000
fe20: 00000000 40000013 0233a240 00000032 00000000 00000000 c00540a8 c0054044
fe40: 00000000 c3a6e000 c3a6fe7c 3b9aca00 00000032 00000000 00000000 00000000
fe60: 00000000 c3a6fef8 c3a6fe94 c3a6fe78 c00529cc c0052758 00000000 00000000
fe80: 00000001 3b9aca00 c3a6fed4 c3a6fe98 c02569ac c00529b4 00000000 00000000
fea0: c3a6e000 00000000 c02f9de0 00000000 00000000 00000000 c3a6ff80 c3a6e000
fec0: 00000000 00000000 c3a6ff64 c3a6fed8 c0052a8c c0256904 00000000 00000000
fee0: 38a09550 00000000 0233a240 00000032 00000000 00000000 c0310700 00000000
ff00: 00000000 00000000 0233a240 00000032 0233a240 00000032 c0051e68 c02f9de0
ff20: 00000001 c3a6ff24 c3a6ff24 00000001 c3a63680 c003bf78 c3a6ff88 00000001
ff40: 00000001 00000000 c3a6ff80 c0025f44 c3a6e000 00017690 c3a6ff7c c3a6ff68
ff60: c004c8d0 c00529e4 c0025f44 00000001 c3a6ffa4 c3a6ff80 c004ca00 c004c8b4
ff80: 00000032 0233a240 00000001 00000000 5396ddec 00000109 00000000 c3a6ffa8
ffa0: c0025dc0 c004c8e4 00000001 00000000 00000001 00000001 5396ddec 00000000
ffc0: 00000001 00000000 5396ddec 00000109 00000001 00015c60 00017690 5396ddf4
ffe0: 00000000 5396dc50 4004680c 4004682c 60000010 00000001 00000000 00000000
Backtrace:
[<c002ef18>] (clkevt32k_next_event+0x0/0xd8) from [<c005a20c>] (clockevents_prog
ram_event+0xfc/0x168)
r6:00000000 r5:000225c1 r4:00000000
[<c005a110>] (clockevents_program_event+0x0/0x168) from [<c005aed4>] (tick_dev_p
rogram_event+0xcc/0xf8)
r8:c02f6a30 r7:00000032 r6:0082d07d r5:00000032 r4:0083ad27
[<c005ae08>] (tick_dev_program_event+0x0/0xf8) from [<c005af78>] (tick_program_e
vent+0x30/0x3c)
[<c005af48>] (tick_program_event+0x0/0x3c) from [<c0052188>] (hrtimer_interrupt+
0x244/0x2e8)
r5:0082947f r4:c02f9de0
[<c0051f44>] (hrtimer_interrupt+0x0/0x2e8) from [<c002f0a4>] (at91rm9200_timer_i
nterrupt+0xb4/0xc8)
[<c002eff0>] (at91rm9200_timer_interrupt+0x0/0xc8) from [<c0065168>] (handle_IRQ
_event+0x54/0xec)
r6:c3a6e000 r5:00010002 r4:c02f6a08
[<c0065114>] (handle_IRQ_event+0x0/0xec) from [<c0067908>] (handle_level_irq+0x1
04/0x174)
[<c0067804>] (handle_level_irq+0x0/0x174) from [<c002506c>] (_text+0x6c/0x8c)
r7:00000002 r6:00000000 r5:c0302d40 r4:00000001
[<c0025000>] (_text+0x0/0x8c) from [<c00259dc>] (__irq_svc+0x3c/0x80)
Exception stack(0xc3a6fdd0 to 0xc3a6fe18)
fdc0: 00000000 c3a67ef8 c3a5fef8 40000013
fde0: 40000013 00000000 0233a240 00000032 c3a6fef8 c02f9de0 c3a6e000 c3a6fe74
fe00: c3a67ef8 c3a6fe18 c3a47ef8 c00528a4 60000013 ffffffff
r6:00000001 r5:fefff000 r4:ffffffff
[<c0052748>] (__hrtimer_start_range_ns+0x0/0x228) from [<c00529cc>] (hrtimer_sta
rt_range_ns+0x28/0x30)
[<c00529a4>] (hrtimer_start_range_ns+0x0/0x30) from [<c02569ac>] (do_nanosleep+0
xb8/0x114)
[<c02568f4>] (do_nanosleep+0x0/0x114) from [<c0052a8c>] (hrtimer_nanosleep+0xb8/
0x140)
[<c00529d4>] (hrtimer_nanosleep+0x0/0x140) from [<c004c8d0>] (common_nsleep+0x2c
/0x30)
[<c004c8a4>] (common_nsleep+0x0/0x30) from [<c004ca00>] (sys_clock_nanosleep+0x1
2c/0x150)
r4:00000001
[<c004c8d4>] (sys_clock_nanosleep+0x0/0x150) from [<c0025dc0>] (ret_fast_syscall
+0x0/0x2c)
r7:00000109 r6:5396ddec r5:00000000 r4:00000001
Code: e59f1040 e88d5000 eb0024fc e3a03000 (e5833000)
Kernel panic - not syncing: Fatal exception in interrupt
Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = c0004000
[00000000] *pgd=00000000
Internal error: Oops: 817 [#1] PREEMPT
Modules linked in:
CPU: 0 Not tainted (2.6.29.6-rt23 #1)
PC is at clkevt32k_next_event+0x94/0xd8
LR is at rt_mutex_unlock+0x10/0x14
pc : [<c002efac>] lr : [<c0256e40>] psr: 00000093
sp : c02f3d90 ip : c02f3ca0 fp : c02f3db4
r10: 00000000 r9 : 00000000 r8 : c02f6a30
r7 : 0000004a r6 : 00000000 r5 : 00000001 r4 : 00000000
r3 : 00000000 r2 : 00010002 r1 : 60000093 r0 : 00000062
Flags: nzcv IRQs off FIQs on Mode SVC_32 ISA ARM Segment kernel
Control: c000717f Table: 23890000 DAC: 00000017
Process swapper (pid: 0, stack limit = 0xc02f2270)
Stack: (0xc02f3d90 to 0xc02f4000)
3d80: 0000c6c0 c02f6a30 131806f5 00000000
3da0: 000225c1 00000000 c02f3ddc c02f3db8 c005a20c c002ef28 0000004a 13797362
3dc0: 0000004a 13796120 0000004a c02f6a30 c02f3e2c c02f3de0 c005aed4 c005a120
3de0: 13796120 0000004a 4f140486 00000000 00000000 c02f3e70 13796120 0000004a
3e00: 4e6c7a07 13797362 0000004a 0000004a c02f9de0 13797362 0000004a c02f2000
3e20: c02f3e4c c02f3e30 c005af78 c005ae18 00000001 00000000 c02f9de0 13793a86
3e40: c02f3eac c02f3e50 c0052188 c005af58 3fd06258 c02f6a30 13793a86 0000004a
3e60: c0065168 c02f9de0 00000001 00000000 13793a86 0000004a c02f2000 c0302d40
3e80: c02f3e9c c02f6a08 00010002 c02f2000 00000001 00000000 00000000 00000001
3ea0: c02f3ecc c02f3eb0 c002f0a4 c0051f54 c38eb1e0 c02f6a08 00010002 c02f2000
3ec0: c02f3efc c02f3ed0 c0065168 c002f000 c02f3ef4 c02fa4f8 c02f2000 c02f6a08
3ee0: 00000001 00000001 c02f2000 2001fce8 c02f3f1c c02f3f00 c0067908 c0065124
3f00: 00000001 c0302d40 00000000 00000002 c02f3f3c c02f3f20 c002506c c0067814
3f20: c02f3f54 ffffffff fefff000 00000001 c02f3f94 c02f3f40 c00259dc c0025010
3f40: 00000000 00000001 c02f2000 60000013 c0026eb0 c02f2000 c02f5eb0 c03104e0
3f60: 2001fd1c 41129200 2001fce8 c02f3f94 c02f3f98 c02f3f88 c0026ef0 c0026efc
3f80: 60000013 ffffffff c02f3fb4 c02f3f98 c0026db0 c0026ec0 c02f2000 c031048c
3fa0: c00222c0 c02f5ce0 c02f3fcc c02f3fb8 c02540dc c0026d70 c031048c c03195fc
3fc0: c02f3ff4 c02f3fd0 c0008b38 c0254068 c0008594 00000000 00000000 c0021ebc
3fe0: c0007175 c0310518 00000000 c02f3ff8 20008034 c0008970 00000000 00000000
Backtrace:
[<c002ef18>] (clkevt32k_next_event+0x0/0xd8) from [<c005a20c>] (clockevents_prog
ram_event+0xfc/0x168)
r6:00000000 r5:000225c1 r4:00000000
[<c005a110>] (clockevents_program_event+0x0/0x168) from [<c005aed4>] (tick_dev_p
rogram_event+0xcc/0xf8)
r8:c02f6a30 r7:0000004a r6:13796120 r5:0000004a r4:13797362
[<c005ae08>] (tick_dev_program_event+0x0/0xf8) from [<c005af78>] (tick_program_e
vent+0x30/0x3c)
[<c005af48>] (tick_program_event+0x0/0x3c) from [<c0052188>] (hrtimer_interrupt+
0x244/0x2e8)
r5:13793a86 r4:c02f9de0
[<c0051f44>] (hrtimer_interrupt+0x0/0x2e8) from [<c002f0a4>] (at91rm9200_timer_i
nterrupt+0xb4/0xc8)
[<c002eff0>] (at91rm9200_timer_interrupt+0x0/0xc8) from [<c0065168>] (handle_IRQ
_event+0x54/0xec)
r6:c02f2000 r5:00010002 r4:c02f6a08
[<c0065114>] (handle_IRQ_event+0x0/0xec) from [<c0067908>] (handle_level_irq+0x1
04/0x174)
[<c0067804>] (handle_level_irq+0x0/0x174) from [<c002506c>] (_text+0x6c/0x8c)
r7:00000002 r6:00000000 r5:c0302d40 r4:00000001
[<c0025000>] (_text+0x0/0x8c) from [<c00259dc>] (__irq_svc+0x3c/0x80)
Exception stack(0xc02f3f40 to 0xc02f3f88)
3f40: 00000000 00000001 c02f2000 60000013 c0026eb0 c02f2000 c02f5eb0 c03104e0
3f60: 2001fd1c 41129200 2001fce8 c02f3f94 c02f3f98 c02f3f88 c0026ef0 c0026efc
3f80: 60000013 ffffffff
r6:00000001 r5:fefff000 r4:ffffffff
[<c0026eb0>] (default_idle+0x0/0x54) from [<c0026db0>] (cpu_idle+0x50/0xac)
[<c0026d60>] (cpu_idle+0x0/0xac) from [<c02540dc>] (rest_init+0x84/0x9c)
r7:c02f5ce0 r6:c00222c0 r5:c031048c r4:c02f2000
[<c0254058>] (rest_init+0x0/0x9c) from [<c0008b38>] (start_kernel+0x1d8/0x2c8)
r4:c03195fc
[<c0008960>] (start_kernel+0x0/0x2c8) from [<20008034>] (0x20008034)
r5:c0310518 r4:c0007175
Code: e59f1040 e88d5000 eb0024fc e3a03000 (e5833000)
Kernel panic - not syncing: Fatal exception in interrupt
