Kernel failure while writing DVD-RAM

[Gilboa Davara]

On Thu, 2009-11-12 at 16:10 +0000, Dave Higton wrote:
> I'm testing DVD-RAM writing and reading for reliability under Fedoras 10
> and 5.  While writing some files under F10 this afternoon, there was a
> kernel failure.  Details below:
> 
> WARNING: at fs/buffer.c:1186 mark_buffer_dirty+0x27/0x79() (Not tainted)
> Hardware name: OptiPlex 755                 
> Modules linked in: udf crc_itu_t fuse i915 drm bridge stp bnep sco l2cap
> bluetooth sunrpc nf_conntrack_netbios_ns nf_conntrack_ftp ip6t_REJECT
> nf_conntrack_ipv6 ip6table_filter ip6_tables ipv6 cpufreq_ondemand
> acpi_cpufreq dm_multipath uinput snd_hda_intel snd_seq_dummy snd_seq_oss
> snd_seq_midi_event snd_seq snd_seq_device snd_pcm_oss snd_mixer_oss
> snd_pcm snd_timer snd_page_alloc snd_hwdep ata_generic i2c_i801 snd
> ppdev i2c_core iTCO_wdt iTCO_vendor_support parport_pc pata_acpi
> serio_raw dcdbas soundcore pcspkr parport e1000e e1000 joydev [last
> unloaded: microcode]
> Pid: 12876, comm: fillDVD2 Not tainted 2.6.27.37-170.2.104.fc10.i686 #1
>  [<c042ddfb>] warn_on_slowpath+0x65/0x8b
>  [<c04228dc>] ? __enqueue_entity+0xe3/0xeb
>  [<c0424346>] ? enqueue_entity+0x203/0x20b
>  [<c06abe09>] ? _spin_lock+0x8/0xb
>  [<c0495510>] ? inode_sub_bytes+0x69/0x71
>  [<c04afeef>] mark_buffer_dirty+0x27/0x79
>  [<f8ea4cb3>] udf_bitmap_free_blocks+0xf8/0x12e [udf]
>  [<f8ea51ba>] udf_free_blocks+0x62/0x8c [udf]
>  [<f8eae3f1>] extent_trunc+0xe5/0xf0 [udf]
>  [<f8eae88a>] udf_discard_prealloc+0xce/0x17b [udf]
>  [<f8ea5844>] udf_release_file+0x18/0x22 [udf]
>  [<c04939ad>] __fput+0xad/0x13d
>  [<c0493a54>] fput+0x17/0x19
>  [<c04912e7>] filp_close+0x50/0x5a
>  [<c0491363>] sys_close+0x72/0xb1
>  [<c0404c8a>] syscall_call+0x7/0xb
>  =======================
> ---[ end trace d4c5a1d53380a8a7 ]---
> 
> This is a standard installation from a Fedora 10 DVD, whose image was
> taken from the web.
> 
> Other than "yup, it's broken", does the above trace mean anything to
> anyone, and is there anything I can do to make it work reliably or even
> to diagnose it further?
> 
> fillDVD2 is my app, written in C, which simply writes sequential files
> of 1 MB each to the DVD on /dev/sr0.  I can post the source if anyone
> wants to see it.
> 
> Looking further ahead, the aim was to try to fix writing DVD-RAM under
> Fedora 5.  We know this is broken, and I was hoping to back-port the F10
> code to F5.  Up to now, we had only observed failures under F5, never
> F10 - this is the first.  The failures were entirely different: F5 would
> occasionally fail to write beyond 4 GB, and would consistently write
> DVD-RAMs that showed allocation errors when examined by the Philips
> udf_test application.  F10 has never exhibited either of those failures.
> F5 has never shown an oops.  Now it seems I can no longer rely on the
> F10 UDF code either.
> 
> Dave
> 

Dave,

This doesn't look like an oops. This is a simple WARN_ON (or actually,
in this case, warn_slowpath). Are you getting a real crash or some kind
of failure.

Can you please post:
A. Kernel version.
B. Serial port output. (Should capture the actual OOPs)

Beyond that, F10 is nearing EOL. I'd suggest you hurry up and file a bug
report before it dies. Maybe the Fedora kernel guys will fix in the last
F10 update. (I'd also include the fillDVD code in the bug report.)

As for back-porting fixes from F10 to F5, I'd consider switching to
CentOS/RHEL 5.4 instead, and back porting only the important stuff you
really (really) need from F10.

P.S. Are you by any chance related to Nice U.K? If so, please say
"Hello" to Russ.

- Gilboa