From mboxrd@z Thu Jan  1 00:00:00 1970
From: Wolfgang Grandegger <wg@grandegger.com>
Subject: patch-2.6.20-rt5: time warp detected!
Date: Mon, 19 Feb 2007 18:00:37 +0100
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Hello,

sometimes I get the following message when calling ktime_get_real() from 
my interrupt handler:

BUG: time warp detected!
prev > now, 104357354c79dfed > 1043573435312fb2:
= 4685606971 delta, on CPU#0
  [<c0103d51>] dump_trace+0x68/0x1d9
  [<c0103edd>] show_trace_log_lvl+0x1b/0x36
  [<c01044dd>] show_trace+0xf/0x11
  [<c010455e>] dump_stack+0x12/0x14
  [<c012f1b2>] ktime_get_real+0x10/0x2c
  [<e09c03ad>] rtcan_rcv+0x12/0x99 [xeno_can]
  [<e09c951d>] rtcan_sja_interrupt+0x220/0x43e [xeno_can_sja1000]
  [<e0992018>] _rtdm_irq_trampoline+0x15/0x34 [xeno_rtdm]
  [<c0145eb7>] handle_IRQ_event+0x41/0xb7
  [<c0146334>] thread_simple_irq+0x31/0x5f
  [<c01468f8>] do_irqd+0xbd/0x249
  [<c012c531>] kthread+0xa0/0xcb
  [<c010397b>] kernel_thread_helper+0x7/0x10
  =======================
---------------------------
| preempt count: 00000000 ]
| 0-level deep critical section nesting:
----------------------------------------

Any idea how this can happen?

Thanks.

Wolfgang.