lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Thu, 21 Feb 2008 07:51:48 -0500 (EST)
From:	Steven Rostedt <rostedt@...dmis.org>
To:	Mark Hounschell <dmarkh@....rr.com>
cc:	linux-kernel <linux-kernel@...r.kernel.org>,
	Ingo Molnar <mingo@...e.hu>,
	Mark Hounschell <markh@...pro.net>,
	Thomas Gleixner <tglx@...utronix.de>,
	Jon Masters <jonathan@...masters.org>
Subject: Re: 2.6.24-rt1 IRQ routing anomaly

[CC'd Thomas and Jon]

Thomas, Jon, looks like the someone has the funny interrupt controller.

On Thu, 21 Feb 2008, Mark Hounschell wrote:

> According to /proc/interrupts, every interrupt received by eth1 is also
> being received by the sound card EMU10K1. The problem showed itself
> first with this. The sound system was quiet BTW.
>
> It does not happen with 2.6.24 vanilla.
>
> kernel: irq 19: nobody cared (try booting with the "irqpoll" option)
> kernel: Pid: 1832, comm: IRQ-19 Not tainted 2.6.24.2-crt #2
> kernel:  [<c013d6da>] __report_bad_irq+0x36/0x75
> kernel:  [<c013d910>] note_interrupt+0x1f7/0x227
> kernel:  [<c013ce85>] thread_simple_irq+0x61/0x74
> kernel:  [<c013d455>] do_irqd+0x0/0x22f
> kernel:  [<c013d507>] do_irqd+0xb2/0x22f
> kernel:  [<c013d455>] do_irqd+0x0/0x22f
> kernel:  [<c012b137>] kthread+0x38/0x5d
> kernel:  [<c012b0ff>] kthread+0x0/0x5d
> kernel:  [<c0104c13>] kernel_thread_helper+0x7/0x10
> kernel:  =======================
> kernel: ---------------------------
> kernel: | preempt count: 00000001 ]
> kernel: | 1-level deep critical section nesting:
> kernel: ----------------------------------------
> kernel: .. [<c02b03b3>] .... __spin_lock_irq+0xe/0x1e
> kernel: .....[<00000000>] ..   ( <= _stext+0x3feff000/0x14)
> kernel:
> kernel: handlers:
> kernel: [<f4d16544>] (snd_emu10k1_interrupt+0x0/0x42c [snd_emu10k1])
> kernel: turning off IO-APIC fast mode.
> kernel: irq 19: nobody cared (try booting with the "irqpoll" option)
> kernel: Pid: 1832, comm: IRQ-19 Not tainted 2.6.24.2-crt #2
> kernel:  [<c013d6da>] __report_bad_irq+0x36/0x75
> kernel:  [<c013d910>] note_interrupt+0x1f7/0x227
> kernel:  [<c013ce85>] thread_simple_irq+0x61/0x74
> kernel:  [<c013d455>] do_irqd+0x0/0x22f
> kernel:  [<c013d507>] do_irqd+0xb2/0x22f
> kernel:  [<c013d455>] do_irqd+0x0/0x22f
> kernel:  [<c012b137>] kthread+0x38/0x5d
> kernel:  [<c012b0ff>] kthread+0x0/0x5d
> kernel:  [<c0104c13>] kernel_thread_helper+0x7/0x10
> kernel:  =======================
> kernel: ---------------------------
> kernel: | preempt count: 00000001 ]
> kernel: | 1-level deep critical section nesting:
> kernel: ----------------------------------------
> kernel: .. [<c02b03b3>] .... __spin_lock_irq+0xe/0x1e
> kernel: .....[<00000000>] ..   ( <= _stext+0x3feff000/0x14)
> kernel:
> kernel: handlers:
> kernel: [<f4d16544>] (snd_emu10k1_interrupt+0x0/0x42c [snd_emu10k1])
>
> Looking at /proc/interrupts I could see the the EMU10K1 interrupt was
> going to town. I was busy busy on eth1 at the time.
>
> So a simple externall ping test with a quiet system at run level-3 revealed:
>
> # lspci cat before.ping
>            CPU0       CPU1
>   0:         85          0   IO-APIC-edge      timer
>   1:        396        420   IO-APIC-edge      i8042
>   3:          4          2   IO-APIC-edge
>   4:          5          1   IO-APIC-edge
>   6:          1          4   IO-APIC-edge      floppy
>   7:          0          0   IO-APIC-edge      parport0
>   8:          2          0   IO-APIC-edge      rtc
>   9:          0          1   IO-APIC-fasteoi   acpi
>  12:         21         84   IO-APIC-edge      i8042
>  14:       8457       8179   IO-APIC-edge      libata
>  15:       1016       1519   IO-APIC-edge      libata
>  16:         60         60   IO-APIC-fasteoi   aic7xxx
>  17:        113         96   IO-APIC-fasteoi   eth1
>  18:         44         47   IO-APIC-fasteoi
>  19:         99        114   IO-APIC-fasteoi   EMU10K1
> NMI:          0          0   Non-maskable interrupts
> LOC:      93895      94157   Local timer interrupts
> RES:       8831       8188   Rescheduling interrupts
> CAL:       4176       5267   function call interrupts
> TLB:        271        235   TLB shootdowns
> TRM:          0          0   Thermal event interrupts
> SPU:          0          0   Spurious interrupts
> ERR:          0
> MIS:          0
>
>
> Then from an external machine: ping -c10 10.10.10.200
>
>
> # cat after.ping
>            CPU0       CPU1
>   0:         85          0   IO-APIC-edge      timer
>   1:        464        432   IO-APIC-edge      i8042
>   3:          4          2   IO-APIC-edge
>   4:          5          1   IO-APIC-edge
>   6:          1          4   IO-APIC-edge      floppy
>   7:          0          0   IO-APIC-edge      parport0
>   8:          2          0   IO-APIC-edge      rtc
>   9:          0          1   IO-APIC-fasteoi   acpi
>  12:         21         84   IO-APIC-edge      i8042
>  14:       8460       8198   IO-APIC-edge      libata
>  15:       1360       1549   IO-APIC-edge      libata
>  16:         60         60   IO-APIC-fasteoi   aic7xxx
>  17:        129        102   IO-APIC-fasteoi   eth1
>  18:         44         47   IO-APIC-fasteoi
>  19:        105        130   IO-APIC-fasteoi   EMU10K1
> NMI:          0          0   Non-maskable interrupts
> LOC:     104387     104637   Local timer interrupts
> RES:       8890       8214   Rescheduling interrupts
> CAL:       4176       5267   function call interrupts
> TLB:        271        236   TLB shootdowns
> TRM:          0          0   Thermal event interrupts
> SPU:          0          0   Spurious interrupts
> ERR:          0
> MIS:          0
>
>
> 44 interrupts added to both eth1 and EMU10K1

This is a known problem with this. Some interrupt controlers are funny
and do funny things when an interrupt is masked, but interrupts enabled.
They route the interrupt to the wrong interrupt line. The only reason that
vanilla doesn't show it, is that vanilla does the interrupt handler
when the interrupt is triggered, so it has no need to mask. RT on the
other hand, runs interrupts in threaded context, which triggers this
little quirk because we mask the interrupt. For some strange reason, the
interrupt controller will trigger the interrupt for another interrupt, if
that interrupt line is masked.

To prove this is the problem, boot with noapic in the kernel command line.
1) the problem should disappear.
2) (I'm betting) you see that the eth and EMU10K1 share the same
   interrupt line.

I see from the back trace that this is i386. We have a workaround for this
on x86_64. Jon Masters has been working on better solutions too.

-- Steve

>
>
> #lspci
>
> 00:00.0 Host bridge: Advanced Micro Devices [AMD] AMD-760 MP [IGD4-2P]
> System Controller (rev 20)
> 00:01.0 PCI bridge: Advanced Micro Devices [AMD] AMD-760 MP [IGD4-2P]
> AGP Bridge
> 00:07.0 ISA bridge: Advanced Micro Devices [AMD] AMD-768 [Opus] ISA (rev 05)
> 00:07.1 IDE interface: Advanced Micro Devices [AMD] AMD-768 [Opus] IDE
> (rev 04)
> 00:07.3 Bridge: Advanced Micro Devices [AMD] AMD-768 [Opus] ACPI (rev 03)
> 00:08.0 Ethernet controller: 3Com Corporation 3c905C-TX/TX-M [Tornado]
> (rev 6c)
> 00:09.0 Class Class ff00: Compro Computer Services, Inc. Unknown device
> 4610 (rev 03)
> 00:10.0 PCI bridge: Advanced Micro Devices [AMD] AMD-768 [Opus] PCI (rev 05)
> 01:05.0 VGA compatible controller: nVidia Corporation NV25 [GeForce4 Ti
> 4400] (rev a2)
> 02:04.0 Multimedia audio controller: Creative Labs SB Live! EMU10k1 (rev 04)
> 02:04.1 Input device controller: Creative Labs SB Live! Game Port (rev 01)
> 02:05.0 Communication controller: National Instruments PCI-GPIB (rev 01)
> 02:06.0 SCSI storage controller: Adaptec AHA-2930CU (rev 03)
> 02:07.0 Communication controller: National Instruments PCI-GPIB (rev 01)
> 02:08.0 Ethernet controller: 3Com Corporation 3c905C-TX/TX-M [Tornado]
> (rev 78)
>
> Again this does not happen with 2.6.24 vanilla. I'm not sure about
> earlier RT kernels.
>
> Regards
> Mark
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ