From: Andrew Morton <akpm@osdl.org>

With CONFIG_FRAME_POINTER, profile=1:

Intel(R) Xeon(TM) CPU 3.40GHz stepping 04
Booting processor 2/4 APIC 0x1
Initializing CPU#2
Calibrating delay using timer specific routine.. 6800.36 BogoMIPS (lpj=13600730)
CPU: Trace cache: 12K uops, L1 D cache: 16K
CPU: L2 cache: 1024K
CPU: Physical Processor ID: 0
CPU2: Thermal monitoring enabled (TM1)
                  Intel(R) Xeon(TM) CPU 3.40GHz stepping 04
APIC error on CPU2: 00(40)
Unable to handle kernel NULL pointer dereference at 000000000000001b RIP: 
<ffffffff8020c7b3>{profile_pc+37}
PGD 0 
Oops: 0000 [1] PREEMPT SMP 
last sysfs file: 
CPU 0 
Modules linked in:
Pid: 1, comm: idle Not tainted 2.6.17-rc4-mm2 #88
RIP: 0010:[<ffffffff8020c7b3>] <ffffffff8020c7b3>{profile_pc+37}
RSP: 0000:ffffffff806a2f38  EFLAGS: 00010002
RAX: 0000000000000013 RBX: ffffffff804c4182 RCX: 0000000000000296
RDX: ffffffff804c4182 RSI: ffff81017fc7bcb8 RDI: ffffffff804c4182
RBP: ffffffff806a2f48 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000013 R12: ffff81017fc7bcb8
R13: ffff81017fc6c800 R14: 0000000000000002 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffffffff80719000(0000) knlGS:0000000000000000
CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
CR2: 000000000000001b CR3: 0000000000201000 CR4: 00000000000006e0
Process idle (pid: 1, threadinfo ffff81017fc7a000, task ffff81017fc5c7c0)
Stack: ffff81017fc7bcb8 0000000000000001 ffffffff806a2f68 ffffffff8022c644 
       ffff81017fc7bcb8 ffffffff807668a0 ffffffff806a2f88 ffffffff802149c6 
       0000000000000296 ffff81017fc7bcb8 
Call Trace: <IRQ> <ffffffff8022c644>{profile_tick+70}
       <ffffffff802149c6>{smp_local_timer_interrupt+22} <ffffffff80214a38>{smp_apic_timer_interrupt+62}
       <ffffffff80209f55>{apic_timer_interrupt+101} <EOI> <ffffffff804c4182>{_spin_unlock_irqrestore+17}
       <ffffffff80223c8d>{try_to_wake_up+1015} <ffffffff80223caf>{wake_up_process+16}
       <ffffffff80226c70>{migration_call+283} <ffffffff804c6771>{notifier_call_chain+41}
       <ffffffff802381ce>{blocking_notifier_call_chain+61}
       <ffffffff80247350>{cpu_up+174} <ffffffff802070cb>{init+143}
       <ffffffff804c4244>{_spin_unlock_irq+20} <ffffffff802240d4>{schedule_tail+67}
       <ffffffff8020a26a>{child_rip+8} <ffffffff8020703c>{init+0}
       <ffffffff8020a262>{child_rip+0}

Code: 48 8b 50 08 5b 48 89 d0 41 5c 5d c3 55 48 89 e5 53 56 83 3d 
RIP <ffffffff8020c7b3>{profile_pc+37} RSP <ffffffff806a2f38>
CR2: 000000000000001b
 <0>Kernel panic - not syncing: Aiee, killing interrupt handler!
 BUG: warning at kernel/panic.c:138/panic()

Call Trace: <IRQ> <ffffffff8022b019>{panic+557} <ffffffff804c418c>{_spin_unlock_irqrestore+27}
       <ffffffff80339392>{__up_read+178} <ffffffff802381d8>{blocking_notifier_call_chain+71}
       <ffffffff8022da77>{do_exit+158} <ffffffff804c418c>{_spin_unlock_irqrestore+27}
       <ffffffff804c66c9>{do_page_fault+1950} <ffffffff804c41d4>{_spin_unlock+43}
       <ffffffff8020cd35>{timer_interrupt+35} <ffffffff804c41d4>{_spin_unlock+43}
       <ffffffff8024fe5d>{__do_IRQ+248} <ffffffff8020a0b1>{error_exit+0}
       <ffffffff804c4182>{_spin_unlock_irqrestore+17} <ffffffff804c4182>{_spin_unlock_irqrestore+17}
       <ffffffff804c4182>{_spin_unlock_irqrestore+17} <ffffffff8020c7b3>{profile_pc+37}
       <ffffffff8020c7a7>{profile_pc+25} <ffffffff8022c644>{profile_tick+70}
       <ffffffff802149c6>{smp_local_timer_interrupt+22} <ffffffff80214a38>{smp_apic_timer_interrupt+62}
       <ffffffff80209f55>{apic_timer_interrupt+101} <EOI> <ffffffff804c4182>{_spin_unlock_irqrestore+17}
       <ffffffff80223c8d>{try_to_wake_up+1015} <ffffffff80223caf>{wake_up_process+16}
       <ffffffff80226c70>{migration_call+283} <ffffffff804c6771>{notifier_call_chain+41}
       <ffffffff802381ce>{blocking_notifier_call_chain+61}
       <ffffffff80247350>{cpu_up+174} <ffffffff802070cb>{init+143}
       <ffffffff804c4244>{_spin_unlock_irq+20} <ffffffff802240d4>{schedule_tail+67}
       <ffffffff8020a26a>{child_rip+8} <ffffffff8020703c>{init+0}
       <ffffffff8020a262>{child_rip+0}

Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---

 arch/x86_64/kernel/time.c |    4 ----
 1 files changed, 4 deletions(-)

diff -puN arch/x86_64/kernel/time.c~revert-x86_64-mm-profile-pc-fp arch/x86_64/kernel/time.c
--- 25/arch/x86_64/kernel/time.c~revert-x86_64-mm-profile-pc-fp	2006-05-20 03:07:18.000000000 -0700
+++ 25-akpm/arch/x86_64/kernel/time.c	2006-05-20 03:07:18.000000000 -0700
@@ -187,16 +187,12 @@ unsigned long profile_pc(struct pt_regs 
 	   Better would be to write these functions in assembler again
 	   and check exactly. */
 	if (in_lock_functions(pc)) {
-#ifdef CONFIG_FRAME_POINTER
-		return ((unsigned long *)(regs->rbp))[1];
-#else
 		char *v = *(char **)regs->rsp;
 		if ((v >= _stext && v <= _etext) ||
 			(v >= _sinittext && v <= _einittext) ||
 			(v >= (char *)MODULES_VADDR  && v <= (char *)MODULES_END))
 			return (unsigned long)v;
 		return ((unsigned long *)regs->rsp)[1];
-#endif
 	}
 	return pc;
 }
_