Hi Florian, Thanks for the report, addition of MRW support to cdrom.c exposed bugs in ide-scsi locking. ide-scsi is a "virtual" host driver which is a bridge between IDE and SCSI subsystems so fixing ide-scsi requires assuring that locking is correct both for IDE and SCSI "side".
Required changes consist of: * adding reference counting to ide-scsi (now in ide-dev-2.6 tree) * fixing various races in IDE device drivers to make conversion to driver model possible (now in ide-dev-2.6 tree) * converting IDE device drivers to driver model (posted for review) * fixing reference counting w.r.t. SCSI subsystem (in testing) With all the above changes I can rmmod ide-scsi safely. In short: this will hopefully get fixed in -mm tree soon. Regards, Bartlomiej On Tue, 8 Feb 2005 18:55:29 +0100, Florian Lohoff <[EMAIL PROTECTED]> wrote: > > Hi, > got this oops while unloading ide-scsi (rmmod segfaulted) > > UP P4 1.7Ghz non Preempt, No HT, IDE DVD/CD-RW, IDE Disk, Vanilla > Kernel, (-chaos -> Debian make-kpkg --append-to-version=-chaos) > > Linux chaos 2.6.11-rc3-chaos #1 Fri Feb 4 23:27:57 CET 2005 i686 GNU/Linux > > Unable to handle kernel NULL pointer dereference at virtual address 000001e0 > printing eip: > e089e539 > *pde = 00000000 > Oops: 0000 [#1] > Modules linked in: nls_iso8859_1 isofs autofs4 nfs lockd sunrpc snd_ens1371 > snd_rawmidi snd_ac97_codec snd_pcm_oss snd_mixer_oss snd_pcm snd_timer snd > snd_page_alloc e100 i2c_i801 i2c_core evdev usbhid uhci_hcd usbcore intel_agp > agpgart sr_mod cdrom dm_mod ide_scsi scsi_mod eepro100 mii > CPU: 0 > EIP: 0060:[<e089e539>] Not tainted VLI > EFLAGS: 00010002 (2.6.11-rc3-chaos) > EIP is at idescsi_queue+0x119/0x400 [ide_scsi] > eax: 00000000 ebx: c0971a40 ecx: e08c4a30 edx: dedf8b00 > esi: 00001388 edi: c044e234 ebp: dedf8b54 esp: c910dc94 > ds: 007b es: 007b ss: 0068 > Process rmmod (pid: 11757, threadinfo=c910c000 task=c9eec510) > Stack: dffef380 00000020 00000010 c0971a40 dedf8b00 d9546cb0 dedf8b68 deffcd80 > 000001d4 c044e234 00000293 dedf8b00 ded25400 00000000 e08c47cf dedf8b00 > e08c4a30 e08c76d0 dedf8b88 dedf8b00 df692c00 ded25400 c1583030 e08caa9a > Call Trace: > [<e08c47cf>] scsi_dispatch_cmd+0x16f/0x250 [scsi_mod] > [<e08c4a30>] scsi_done+0x0/0x30 [scsi_mod] > [<e08c76d0>] scsi_times_out+0x0/0xc0 [scsi_mod] > [<e08caa9a>] scsi_request_fn+0x1ca/0x380 [scsi_mod] > [<c0233858>] __elv_add_request+0x78/0xc0 > [<c0236446>] blk_insert_request+0xa6/0xd0 > [<e08c97b8>] scsi_insert_special_req+0x38/0x40 [scsi_mod] > [<e08c9a28>] scsi_wait_req+0x68/0xa0 [scsi_mod] > [<e08c9960>] scsi_wait_done+0x0/0x60 [scsi_mod] > [<e08a3462>] sr_do_ioctl+0x92/0x2a0 [sr_mod] > [<e08a3155>] sr_packet+0x25/0x40 [sr_mod] > [<e08e7a75>] cdrom_get_disc_info+0x65/0xb0 [cdrom] > [<e08e372b>] cdrom_mrw_exit+0x1b/0x70 [cdrom] > [<e08e3323>] unregister_cdrom+0x83/0xb0 [cdrom] > [<e08a319a>] sr_kref_release+0x2a/0x50 [sr_mod] > [<e08a3170>] sr_kref_release+0x0/0x50 [sr_mod] > [<c01bf769>] kref_put+0x39/0xa0 > [<c01bed1f>] kobject_put+0x1f/0x30 > [<e08a31f9>] sr_remove+0x39/0x4b [sr_mod] > [<e08a3170>] sr_kref_release+0x0/0x50 [sr_mod] > [<c022e946>] device_release_driver+0x86/0x90 > [<c022ebc4>] bus_remove_device+0x64/0xb0 > [<c022d8cd>] device_del+0x5d/0xa0 > [<e08cda1f>] scsi_remove_device+0x4f/0xb0 [scsi_mod] > [<e08ccaca>] scsi_forget_host+0x2a/0x50 [scsi_mod] > [<e08c5319>] scsi_remove_host+0x19/0x80 [scsi_mod] > [<e089e2dd>] idescsi_cleanup+0x4d/0x60 [ide_scsi] > [<c024b95e>] ide_unregister_driver+0x5e/0x90 > [<c012f7f8>] try_stop_module+0x28/0x30 > [<e089edef>] exit_idescsi_module+0xf/0x11 [ide_scsi] > [<c012f9b4>] sys_delete_module+0x144/0x180 > [<c0147500>] do_munmap+0xf0/0x160 > [<c01475b4>] sys_munmap+0x44/0x70 > [<c0102f33>] syscall_call+0x7/0xb > Code: 8b 54 24 3c 8b 42 64 89 53 2c 89 43 14 89 43 0c 8b 4c 24 40 89 4b 30 a1 > a0 0d 35 c0 8b 72 3c 01 f0 89 43 38 8b 7c 24 24 8b 47 20 <8b> 80 e0 01 00 00 > a8 01 74 05 0f ba 6b 34 02 8b 43 1c 89 44 24 > > -- > Florian Lohoff [EMAIL PROTECTED] +49-171-2280134 > Heisenberg may have been here. > > > - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
