2012/10/17 Dave Anderson <anderson(a)redhat.com>:
BTW, what happens when you run it against a task that has taken a
kernel-mode exception or kernel-mode interrupt?
The backtrace stops at the exception point:
crash> bt
PID: 0 TASK: c0998778 CPU: 0 COMMAND: "swapper"
#0 [<c0320fb8>] (touch_softlockup_watchdog) from [<c0290030>]
#1 [<c0290030>] (asm_do_IRQ) from [<c029124c>]
pc : [<c02a1e60>] lr : [<c02a1e5c>] psr: 60000013
sp : c0983f18 ip : 00000002 fp : 000021ce
r10: a83a0af5 r9 : 0000289c r8 : c09ead48
r7 : 00000008 r6 : a7979c2b r5 : 00000001 r4 : 00000003
r3 : 00000000 r2 : 00000001 r1 : 80000093 r0 : c09ead8c
Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM
#2 [<c029124c>] (__irq_svc) from [<c02a1e5c>]
#3 [<c02a1e60>] (cpuidle_enter) from [<c05dfa3c>]
#4 [<c05dfa3c>] (cpuidle_idle_call) from [<c0292c98>]
#5 [<c0292c98>] (cpu_idle) from [<c0008cb0>]
#6 [<c0008cb0>] (start_kernel) from [<00008080>]
crash> gdb bt
#0 0xc0320fb8 in touch_softlockup_watchdog () at
/tmp/kernel/kernel/softlockup.c:77
#1 0xc0290030 in asm_do_IRQ (irq=80, regs=0x0) at
/tmp/kernel/arch/arm/kernel/irq.c:109
#2 0xc029124c in __irq_svc () at /tmp/kernel/arch/arm/kernel/entry-armv.S:229
Register 25 is not available
gdb: gdb request failed: bt