On 21.08.2008 [20:11:12 -0500], Robin Holt wrote: > Nish, > > Sounds like the callers to ide_output_data need to be doing some > better alignment of their structures. The thing that is confusing me > is, I believe, my own assumption. Do you know when this problem first > occurred? I have assumed it is very recent, but that does not appear > to be the case. Sorry about that misleading, it was unintentional. I was unable to get serial console output on this box (well, actually, successfully boot it in our test grid), because of CONFIG_PRINTK_TIME breakage that was recently resolved with Tony & Peter Z.'s help. However, I saw these "unaligned access" messages on the first successful boot and hadn't seen them before, so I thought I should report them. I should have been more specific that I was not sure this was a regression, but simply didn't have data for kernels before 2.6.27-rc3. I could go and generate that, but it seems like the IDE folks may have an idea of what is the problem. Sorry again, Nish > > Thanks, > Robin > > > On Thu, Aug 21, 2008 at 05:39:06PM -0700, Nishanth Aravamudan wrote: > > On 21.08.2008 [16:54:26 -0500], Robin Holt wrote: > > > > [ 32.597792] outsl(496, e000000644678466, 3) > > > ^^^^^^^^^^^^^^^^ > > > > > > This is expected to be an unsigned int * and typecast to that in outsl. > > > Looks like the buffer being passed in is not properly aligned. Time to > > > go look at the caller. Make sure buf is defined as an array of at least > > > int size. That should make this aligned on a 4 byte boundary instead of > > > the 2 byte boundary it is on now. > > > > > > You can cheat at finding the callers by putting > > > WARN_ON(buf & 0x3); > > > printk... > > > > So I tried this and it gets quite hairy quickly (I think) because what's > > unaligned is an IDE command buffer? There is a lot of pointer passing > > and I get lost since I don't know the IDE/elevator code very well. > > > > Here's the stack trace I'm looking at: > > > > [ 5.018347] [<a000000100015420>] show_stack+0x80/0xa0 > > [ 5.018348] sp=e00000130307f930 bsp=e0000013030793b8 > > [ 5.031782] [<a000000100015470>] dump_stack+0x30/0x60 > > [ 5.031783] sp=e00000130307fb00 bsp=e0000013030793a0 > > [ 5.045223] [<a000000100094ff0>] warn_on_slowpath+0x90/0xe0 > > [ 5.045225] sp=e00000130307fb00 bsp=e000001303079378 > > [ 5.059201] [<a000000100517480>] ide_output_data+0x3c0/0x540 > > [ 5.059204] sp=e00000130307fbf0 bsp=e000001303079310 > > [ 5.073248] [<a0000001005309e0>] cdrom_transfer_packet_command+0x2c0/0x340 > > [ 5.073249] sp=e00000130307fbf0 bsp=e0000013030792d0 > > [ 5.088519] [<a000000100530ac0>] cdrom_do_newpc_cont+0x60/0x80 > > [ 5.088522] sp=e00000130307fc00 bsp=e0000013030792b0 > > [ 5.102739] [<a00000010052f1a0>] ide_cd_do_request+0x980/0x1420 > > [ 5.102742] sp=e00000130307fc00 bsp=e000001303079238 > > [ 5.117064] [<a00000010050fe00>] ide_do_request+0xca0/0x1d00 > > [ 5.117066] sp=e00000130307fc00 bsp=e0000013030791a0 > > [ 5.131105] [<a000000100511580>] do_ide_request+0x40/0x60 > > [ 5.131107] sp=e00000130307fc30 bsp=e000001303079180 > > [ 5.144897] [<a000000100384780>] elv_insert+0x280/0x5c0 > > [ 5.144900] sp=e00000130307fc30 bsp=e000001303079148 > > [ 5.158507] [<a000000100384c40>] __elv_add_request+0x180/0x240 > > [ 5.158509] sp=e00000130307fc30 bsp=e000001303079110 > > [ 5.172733] [<a000000100391730>] blk_execute_rq_nowait+0xd0/0x1e0 > > [ 5.172734] sp=e00000130307fc30 bsp=e0000013030790d0 > > [ 5.187220] [<a000000100391910>] blk_execute_rq+0xd0/0x240 > > [ 5.187221] sp=e00000130307fc30 bsp=e000001303079090 > > [ 5.201091] [<a000000100531f70>] ide_cd_queue_pc+0x130/0x2e0 > > [ 5.201093] sp=e00000130307fcc0 bsp=e000001303078fd0 > > [ 5.215137] [<a0000001005342f0>] ide_cdrom_packet+0x130/0x180 > > [ 5.215139] sp=e00000130307fd00 bsp=e000001303078f78 > > [ 5.229281] [<a000000100593080>] cdrom_mode_sense+0xc0/0xe0 > > [ 5.229283] sp=e00000130307fd10 bsp=e000001303078f40 > > [ 5.243239] [<a00000010052d9c0>] ide_cdrom_get_capabilities+0x80/0xc0 > > [ 5.243240] sp=e00000130307fd10 bsp=e000001303078f10 > > [ 5.258084] [<a000000100533890>] ide_cd_probe+0x810/0xf40 > > [ 5.258086] sp=e00000130307fd50 bsp=e000001303078e90 > > [ 5.273709] [<a00000010050a510>] generic_ide_probe+0x70/0xa0 > > [ 5.273711] sp=e00000130307fdc0 bsp=e000001303078e70 > > [ 5.287774] [<a0000001004bdaf0>] driver_probe_device+0x190/0x3a0 > > [ 5.287775] sp=e00000130307fdc0 bsp=e000001303078e28 > > [ 5.302163] [<a0000001004bdd80>] __driver_attach+0x80/0xe0 > > [ 5.302164] sp=e00000130307fdc0 bsp=e000001303078de8 > > [ 5.316032] [<a0000001004bc5a0>] bus_for_each_dev+0xc0/0x140 > > [ 5.316034] sp=e00000130307fdc0 bsp=e000001303078db0 > > [ 5.330072] [<a0000001004bd700>] driver_attach+0x40/0x60 > > [ 5.330074] sp=e00000130307fde0 bsp=e000001303078d90 > > [ 5.343761] [<a0000001004bd290>] bus_add_driver+0x370/0x4a0 > > [ 5.343763] sp=e00000130307fde0 bsp=e000001303078d48 > > [ 5.357720] [<a0000001004be3d0>] driver_register+0xd0/0x340 > > [ 5.357721] sp=e00000130307fde0 bsp=e000001303078d00 > > [ 5.371693] [<a0000001009a3ea0>] ide_cdrom_init+0x20/0x40 > > [ 5.371695] sp=e00000130307fde0 bsp=e000001303078ce8 > > [ 5.385475] [<a00000010000a5a0>] do_one_initcall+0x60/0x380 > > [ 5.385477] sp=e00000130307fde0 bsp=e000001303078ca8 > > [ 5.399445] [<a0000001009645b0>] kernel_init+0x370/0x420 > > [ 5.399447] sp=e00000130307fe20 bsp=e000001303078c68 > > [ 5.413148] [<a000000100013590>] kernel_thread_helper+0xd0/0x100 > > [ 5.413149] sp=e00000130307fe30 bsp=e000001303078c40 > > [ 5.427547] [<a00000010000a4c0>] start_kernel_thread+0x20/0x40 > > [ 5.427548] sp=e00000130307fe30 bsp=e000001303078c40 > > > > We are trying to send a sense command to the device and the buffer we > > use (which is rq->cmd) is what is unaligned, I believe. I'm not sure how > > useful I can be going forward... > > > > Thanks, > > Nish > > > > -- > > Nishanth Aravamudan <nacc@xxxxxxxxxx> > > IBM Linux Technology Center -- Nishanth Aravamudan <nacc@xxxxxxxxxx> IBM Linux Technology Center -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
