PROBLEM: ide-cd in 2.6.8-2.6.10 and 2.4.26-2.4.28 high cpu use with dma

Hikaru1_at_verizon.net
Date: 01/09/05

  • Next message: Hikaru1_at_verizon.net: "Re: PROBLEM: ide-cd in 2.6.8-2.6.10 and 2.4.26-2.4.28 high cpu use with dma"
    Date:	Sun, 9 Jan 2005 05:52:01 -0500
    To: axboe@suse.de, linux-kernel@vger.kernel.org
    
    

    Hi, I'm using the bug reporting format described at
    http://www.kernel.org/pub/linux/docs/lkml/reporting-bugs.html - if you need
    any additional information, please contact me.

    [1.] One line summary of the problem:
    Burning cd's causes extremely high cpu use with dma enabled.

    [2.] Full description of the problem/report:
    Burning cd's with linux kernel versions 2.4.26-2.4.28 and 2.6.8-2.6.10 with
    cdrecord as root user causes extremely high 'system' cpu use according to
    top even though dma is enabled on the cdrom drive. Earlier kernel versions
    do not have this problem. The problem is so bad that with 2.6.7 a cd can be
    burned at 28x while with later kernel versions, only 15x or slower can be
    used. Note that the test machine was at one point clean booted without the
    nvidia driver loaded, and still experienced the problem. The test machine is
    a server, so it's not nice to keep rebooting it; therefore the nvidia module
    is shown as loaded in the environment section of this bug report since at
    the time ver_linux was run, it was being used normally.

    [3.] Keywords (i.e., modules, networking, kernel):
    modules, kernel, ide-cd, cd burning

    [4.] Kernel version (from /proc/version):
    2.6.10 on the current test machine, however 2.6.8-2.6.10 and 2.4.26-2.4.28
    also experience the same problems.

    [5.] Output of Oops.. message (if applicable) with symbolic information
         resolved (see Documentation/oops-tracing.txt)
    No oops information, kernel has no panics or oopsing. No misbehavior is
    recorded in syslog.

    [6.] A small shell script or example program which triggers the
         problem (if possible)
    cdrecord run in -dummy mode on any data will reproduce the problem.

    [7.] Environment
    [7.1.] Software (add the output of the ver_linux script here)
    If some fields are empty or look unusual you may have an old version.
    Compare to the current minimal requirements in Documentation/Changes.
     
    Linux qserv 2.6.10 #9 Fri Jan 7 07:16:36 EST 2005 i686 unknown unknown GNU/Linux
     
    Gnu C 3.3.4
    Gnu make 3.80
    binutils 2.15.92.0.2
    util-linux 2.12p
    mount 2.12p
    module-init-tools 3.1
    e2fsprogs 1.35
    reiserfsprogs 3.6.18
    reiser4progs line
    Linux C Library 2.3.3
    Dynamic linker (ldd) 2.3.3
    Linux C++ Library 5.0.6
    Procps 3.2.3
    Net-tools 1.60
    Kbd 1.12
    Sh-utils 5.2.1
    Modules Loaded snd_pcm_oss snd_mixer_oss sch_ingress cls_u32 sch_sfq sch_cbq iptable_nat ipt_limit ipt_state iptable_filter ip_tables snd_emu10k1 snd_rawmidi snd_seq_device snd_ac97_codec snd_pcm snd_timer snd_page_alloc snd_util_mem snd_hwdep snd 3c59x 8139too uhci_hcd nvidia

    [7.2.] Processor information (from /proc/cpuinfo):
    processor : 0
    vendor_id : AuthenticAMD
    cpu family : 6
    model : 8
    model name : AMD Athlon(tm) XP Processor
    stepping : 1
    cpu MHz : 1986.867
    cache size : 256 KB
    fdiv_bug : no
    hlt_bug : no
    f00f_bug : no
    coma_bug : no
    fpu : yes
    fpu_exception : yes
    cpuid level : 1
    wp : yes
    flags : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca cmov pat pse36 mmx fxsr sse pni syscall mmxext 3dnowext 3dnow
    bogomips : 3915.77

    [7.3.] Module information (from /proc/modules):
    snd_pcm_oss 47904 0 - Live 0xf8c1b000
    snd_mixer_oss 17280 1 snd_pcm_oss, Live 0xf8c05000
    sch_ingress 3268 1 - Live 0xf89fd000
    cls_u32 6596 5 - Live 0xf8a6d000
    sch_sfq 4608 2 - Live 0xf8a70000
    sch_cbq 15616 1 - Live 0xf8a73000
    iptable_nat 22152 0 - Live 0xf8b06000
    ipt_limit 1920 1 - Live 0xf8a20000
    ipt_state 1472 2 - Live 0xf8a1e000
    iptable_filter 2944 1 - Live 0xf89de000
    ip_tables 16320 4 iptable_nat,ipt_limit,ipt_state,iptable_filter, Live 0xf8a28000
    snd_emu10k1 95172 0 - Live 0xf8a78000
    snd_rawmidi 20192 1 snd_emu10k1, Live 0xf8a22000
    snd_seq_device 7116 2 snd_emu10k1,snd_rawmidi, Live 0xf89ff000
    snd_ac97_codec 72928 1 snd_emu10k1, Live 0xf8a49000
    snd_pcm 84296 3 snd_pcm_oss,snd_emu10k1,snd_ac97_codec, Live 0xf8a33000
    snd_timer 21252 2 snd_emu10k1,snd_pcm, Live 0xf8a03000
    snd_page_alloc 7556 2 snd_emu10k1,snd_pcm, Live 0xf89e7000
    snd_util_mem 3264 1 snd_emu10k1, Live 0xf89e5000
    snd_hwdep 7364 1 snd_emu10k1, Live 0xf89e2000
    snd 46948 9 snd_pcm_oss,snd_mixer_oss,snd_emu10k1,snd_rawmidi,snd_seq_device,snd_ac97_codec,snd_pcm,snd_timer,snd_hwdep, Live 0xf89ee000
    3c59x 36136 0 - Live 0xf89c4000
    8139too 20544 0 - Live 0xf89d7000
    uhci_hcd 30160 0 - Live 0xf89ce000
    nvidia 3464788 12 - Live 0xf8d7e000

    [7.4.] Loaded driver and hardware information (/proc/ioports, /proc/iomem)
    0000-001f : dma1
    0020-0021 : pic1
    0040-0043 : timer0
    0050-0053 : timer1
    0060-006f : keyboard
    0070-0077 : rtc
    0080-008f : dma page reg
    00a0-00a1 : pic2
    00c0-00df : dma2
    00f0-00ff : fpu
    0170-0177 : ide1
    01f0-01f7 : ide0
    0376-0376 : ide1
    0378-037a : parport0
    03c0-03df : vga+
    03f6-03f6 : ide0
    03f8-03ff : serial
    0cf8-0cff : PCI conf1
    1000-10ff : 0000:00:0a.0
      1000-10ff : 8139too
    1400-147f : 0000:00:09.0
      1400-147f : 0000:00:09.0
    1480-14bf : 0000:00:07.0
      1480-14bf : EMU10K1
    14c0-14df : 0000:00:14.2
      14c0-14df : uhci_hcd
    14e0-14ff : 0000:00:14.3
      14e0-14ff : uhci_hcd
    1800-180f : 0000:00:14.1
      1800-1807 : ide0
      1808-180f : ide1
    1810-1817 : 0000:00:07.1
    1818-181b : 0000:00:00.0
    ec00-ec0f : 0000:00:14.4
    ee00-ee7f : motherboard
      ee00-ee03 : PM1a_EVT_BLK
      ee04-ee05 : PM1a_CNT_BLK
      ee08-ee0b : PM_TMR
      ee20-ee23 : GPE0_BLK
    ee80-eeff : motherboard

    00000000-0009fbff : System RAM
    0009fc00-0009ffff : reserved
    000a0000-000bffff : Video RAM area
    000c0000-000cffff : Video ROM
    000d0000-000d07ff : Adapter ROM
    000ec000-000effff : ACPI Non-volatile Storage
    000f0000-000fffff : System ROM
    00100000-3fffffff : System RAM
      00100000-003053ac : Kernel code
      003053ad-003db2ff : Kernel data
    80000000-80ffffff : PCI Bus #01
      80000000-80ffffff : 0000:01:05.0
        80000000-80ffffff : nvidia
    81000000-81003fff : 0000:00:07.2
    81100000-811007ff : 0000:00:07.2
      81100000-811007ff : ohci1394
    81200000-812000ff : 0000:00:0a.0
      81200000-812000ff : 8139too
    81300000-8130007f : 0000:00:09.0
    81400000-81400fff : 0000:00:00.0
    88000000-8fffffff : PCI Bus #01
      88000000-8fffffff : 0000:01:05.0
    90000000-93ffffff : 0000:00:00.0
    fffc0000-ffffffff : reserved

    [7.5.] PCI information ('lspci -vvv' as root)
    Attached devices:
    00:00.0 Host bridge: Advanced Micro Devices [AMD] AMD-760 [IGD4-1P] System Controller (rev 12)
            Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B-
            Status: Cap+ 66Mhz- UDF- FastB2B- ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort+ >SERR- <PERR-
            Latency: 32
            Region 0: Memory at 90000000 (32-bit, prefetchable) [size=64M]
            Region 1: Memory at 81400000 (32-bit, prefetchable) [size=4K]
            Region 2: I/O ports at 1818 [disabled] [size=4]
            Capabilities: [a0] AGP version 2.0
                    Status: RQ=16 Iso- ArqSz=0 Cal=0 SBA+ ITACoh- GART64- HTrans- 64bit- FW+ AGP3- Rate=x1,x2,x4
                    Command: RQ=1 ArqSz=0 Cal=0 SBA+ AGP+ GART64- 64bit- FW+ Rate=x4

    00:01.0 PCI bridge: Advanced Micro Devices [AMD] AMD-760 [IGD4-1P] AGP Bridge (prog-if 00 [Normal decode])
            Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B-
            Status: Cap- 66Mhz+ UDF- FastB2B- ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
            Latency: 32
            Bus: primary=00, secondary=01, subordinate=01, sec-latency=32
            I/O behind bridge: 0000f000-00000fff
            Memory behind bridge: 80000000-80ffffff
            Prefetchable memory behind bridge: 88000000-8fffffff
            BridgeCtl: Parity- SERR- NoISA+ VGA+ MAbort- >Reset- FastB2B-

    00:07.0 Multimedia audio controller: Creative Labs SB Audigy (rev 04)
            Subsystem: Creative Labs: Unknown device 2002
            Control: I/O+ Mem- BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B-
            Status: Cap+ 66Mhz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
            Latency: 32 (500ns min, 5000ns max)
            Interrupt: pin A routed to IRQ 10
            Region 0: I/O ports at 1480 [size=64]
            Capabilities: [dc] Power Management version 2
                    Flags: PMEClk- DSI+ D1+ D2+ AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
                    Status: D0 PME-Enable- DSel=0 DScale=0 PME-

    00:07.1 Input device controller: Creative Labs SB Audigy MIDI/Game port (rev 04)
            Subsystem: Creative Labs SB Audigy MIDI/Game Port
            Control: I/O+ Mem- BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B-
            Status: Cap+ 66Mhz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
            Latency: 32
            Region 0: I/O ports at 1810 [size=8]
            Capabilities: [dc] Power Management version 2
                    Flags: PMEClk- DSI+ D1+ D2+ AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
                    Status: D0 PME-Enable- DSel=0 DScale=0 PME-

    00:07.2 FireWire (IEEE 1394): Creative Labs SB Audigy FireWire Port (rev 04) (prog-if 10 [OHCI])
            Subsystem: Creative Labs SB Audigy FireWire Port
            Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B-
            Status: Cap+ 66Mhz- UDF- FastB2B- ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
            Latency: 32 (500ns min, 1000ns max), cache line size 08
            Interrupt: pin B routed to IRQ 11
            Region 0: Memory at 81100000 (32-bit, non-prefetchable) [size=2K]
            Region 1: Memory at 81000000 (32-bit, non-prefetchable) [size=16K]
            Capabilities: [44] Power Management version 2
                    Flags: PMEClk- DSI- D1+ D2+ AuxCurrent=0mA PME(D0+,D1+,D2+,D3hot+,D3cold-)
                    Status: D0 PME-Enable- DSel=0 DScale=0 PME+

    00:09.0 Ethernet controller: 3Com Corporation 3c905C-TX/TX-M [Tornado] (rev 74)
            Subsystem: 3Com Corporation 3C905C-TX Fast Etherlink for PC Management NIC
            Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B-
            Status: Cap+ 66Mhz- UDF- FastB2B- ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
            Latency: 32 (2500ns min, 2500ns max), cache line size 08
            Interrupt: pin A routed to IRQ 11
            Region 0: I/O ports at 1400 [size=128]
            Region 1: Memory at 81300000 (32-bit, non-prefetchable) [size=128]
            Expansion ROM at <unassigned> [disabled] [size=128K]
            Capabilities: [dc] Power Management version 2
                    Flags: PMEClk- DSI- D1+ D2+ AuxCurrent=0mA PME(D0+,D1+,D2+,D3hot+,D3cold+)
                    Status: D0 PME-Enable- DSel=0 DScale=2 PME-

    00:0a.0 Ethernet controller: Accton Technology Corporation SMC2-1211TX (rev 10)
            Subsystem: Accton Technology Corporation EN-1207D Fast Ethernet Adapter
            Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B-
            Status: Cap+ 66Mhz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
            Latency: 32 (8000ns min, 16000ns max)
            Interrupt: pin A routed to IRQ 3
            Region 0: I/O ports at 1000 [size=256]
            Region 1: Memory at 81200000 (32-bit, non-prefetchable) [size=256]
            Expansion ROM at <unassigned> [disabled] [size=128K]
            Capabilities: [50] Power Management version 2
                    Flags: PMEClk- DSI- D1+ D2+ AuxCurrent=375mA PME(D0-,D1+,D2+,D3hot+,D3cold+)
                    Status: D0 PME-Enable- DSel=0 DScale=0 PME-

    00:14.0 ISA bridge: VIA Technologies, Inc. VT82C686 [Apollo Super South] (rev 40)
            Subsystem: VIA Technologies, Inc. VT82C686/A PCI to ISA Bridge
            Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping+ SERR- FastB2B-
            Status: Cap+ 66Mhz- UDF- FastB2B- ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
            Latency: 0
            Capabilities: [c0] Power Management version 2
                    Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
                    Status: D0 PME-Enable- DSel=0 DScale=0 PME-

    00:14.1 IDE interface: VIA Technologies, Inc. VT82C586A/B/VT82C686/A/B/VT823x/A/C/VT8235 PIPC Bus Master IDE (rev 06) (prog-if 8a [Master SecP PriP])
            Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B-
            Status: Cap+ 66Mhz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
            Latency: 32
            Region 4: I/O ports at 1800 [size=16]
            Capabilities: [c0] Power Management version 2
                    Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
                    Status: D0 PME-Enable- DSel=0 DScale=0 PME-

    00:14.2 USB Controller: VIA Technologies, Inc. VT6202 [USB 2.0 controller] (rev 16) (prog-if 00 [UHCI])
            Subsystem: VIA Technologies, Inc. (Wrong ID) USB Controller
            Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B-
            Status: Cap+ 66Mhz- UDF- FastB2B- ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
            Latency: 32, cache line size 08
            Interrupt: pin D routed to IRQ 11
            Region 4: I/O ports at 14c0 [size=32]
            Capabilities: [80] Power Management version 2
                    Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
                    Status: D0 PME-Enable- DSel=0 DScale=0 PME-

    00:14.3 USB Controller: VIA Technologies, Inc. VT6202 [USB 2.0 controller] (rev 16) (prog-if 00 [UHCI])
            Subsystem: VIA Technologies, Inc. (Wrong ID) USB Controller
            Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B-
            Status: Cap+ 66Mhz- UDF- FastB2B- ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
            Latency: 32, cache line size 08
            Interrupt: pin D routed to IRQ 11
            Region 4: I/O ports at 14e0 [size=32]
            Capabilities: [80] Power Management version 2
                    Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
                    Status: D0 PME-Enable- DSel=0 DScale=0 PME-

    00:14.4 Bridge: VIA Technologies, Inc. VT82C686 [Apollo Super ACPI] (rev 40)
            Control: I/O- Mem- BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B-
            Status: Cap+ 66Mhz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
            Interrupt: pin ? routed to IRQ 9
            Capabilities: [68] Power Management version 2
                    Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
                    Status: D0 PME-Enable- DSel=0 DScale=0 PME-

    01:05.0 VGA compatible controller: nVidia Corporation NV34 [GeForce FX 5200] (rev a1) (prog-if 00 [VGA])
            Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B-
            Status: Cap+ 66Mhz+ UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
            Latency: 248 (1250ns min, 250ns max)
            Interrupt: pin A routed to IRQ 3
            Region 0: Memory at 80000000 (32-bit, non-prefetchable) [size=16M]
            Region 1: Memory at 88000000 (32-bit, prefetchable) [size=128M]
            Expansion ROM at <unassigned> [disabled] [size=128K]
            Capabilities: [60] Power Management version 2
                    Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
                    Status: D0 PME-Enable- DSel=0 DScale=0 PME-
            Capabilities: [44] AGP version 3.0
                    Status: RQ=32 Iso- ArqSz=0 Cal=0 SBA+ ITACoh- GART64- HTrans- 64bit- FW+ AGP3- Rate=x1,x2,x4
                    Command: RQ=16 ArqSz=0 Cal=0 SBA+ AGP+ GART64- 64bit- FW+ Rate=x4

    [7.6.] SCSI information (from /proc/scsi/scsi)
    Nonexistent proc file. No scsi drivers are loaded.

    [7.7.] Other information that might be relevant to the problem
           (please look in /proc and include all information that you
           think to be relevant):

    Checked with hdparm multiple times during cd writes and dma was enabled
    correctly on the drive even though performance was horrible. BIOS settings
    were checked thoroughly although the settings were unable to be set
    manually, the BIOS is enabling dma on the cd drive.

    The cd drive for all the tests is a PIONEER DVD-RW DVR-108 on /dev/hdd

    [X.] Other notes, patches, fixes, workarounds:

    I had to help the user who owns this system with this problem remotely via
    IRC, but I will direct any questions you have about his computer to him, or
    you can email him yourself at admin [at] tuxq.com. His real name is Steven E.
    Woolard.

    Again, note that even though the environment data shows the nvidia driver is
    loaded on this machine, the machine was tested both with it loaded and
    unloaded with the same effects. The environment data only shows it loaded
    because the machine is a server and the owner doesn't like rebooting it all
    the time. I felt it was fairly pointless to ask him to fetch the environment
    data all over again.

    (workaround? fix? What's this thing DO that I found?)
    After hearing him yell repeatedly that something had broken in the linux
    kernel and determining that 2.6.7 had worked but 2.6.8 didn't, I eyeballed
    the diff of the drivers/ide subdirectory, and found a curious... oddity. On
    a whim, I had him check and it was set the same in 2.6.10, so I had him
    change it to what it had been in 2.6.7 - suddenly cd burning works correctly
    for him.

    For both examples, the line changed is in drivers/ide/ide-cd.c

    In 2.6.8 and later, the line reads:
    blk_queue_dma_alignment(drive->queue, 31);

    In 2.6.7, the line reads:
    blk_queue_dma_alignment(drive->queue, 3);

    To be completely clear, the line from 2.6.7 works correctly while the line
    from 2.6.8 does not. I don't know what this does, only that it causes his
    hardware to work again.

    I tried to find a similar line in the 2.4 series, but was unable to. When I
    have more time I'll try eyeballing the ide diff between 2.4.25 and 2.4.26 and
    see if I stumble into something.

    Honestly, I don't know what this patch actually changes. I'm a novice coder
    in C at best and am just learning the basics, so forgive me for throwing
    this at you without any idea of what its meaning is.

    At a guess, I'd say this is a typo - but whatever it is, I'd love to know.

    I have attached a patch which applies to 2.6.10, or 2.6.8/2.6.9 if you use
    -p1

    Timothy Charles McGrath
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  • Next message: Hikaru1_at_verizon.net: "Re: PROBLEM: ide-cd in 2.6.8-2.6.10 and 2.4.26-2.4.28 high cpu use with dma"

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      (Linux-Kernel)
    • Re: Weird kernel errors
      ... This may be related to the kernel error message: ... >> The second is that my hard disks won't accept DMA enabling, ... No DMA on any of the drives. ... > allotted partitions if they aren't "right"). ...
      (uk.comp.os.linux)
    • Re: cd burning
      ... >> But I'm hitting a wall with the cd burning. ... If the Kernel is installed correctly, ... ide-scsi and loop module should be somewhere in ... The bf2.4 Kernel has the ide-cd, scsi-mod and sr_mod drivers built in. ...
      (Debian-User)