Kernel ata_piix DMA issues [solved]

Question

this is the first time that such a message appeared (i think after a kernel update); something is wrong, cause there are about 15 such messages (different want values) each and every boot.
Feb 3 10:47:23 localhost attempt to access beyond end of device
Feb 3 10:47:23 localhost sdb: rw=0, want=40017915, limit=39062500
but thats not too bad, because it doesn't even add a second to the boot time, and the performance hasn't noticeably changed.
but then, upgrading to 2.6.20, I got this somewhat related message:
Feb 6 21:55:19 localhost scsi2 : ata_piix
Feb 6 21:55:19 localhost ata2.00: ATAPI, max UDMA/33
Feb 6 21:55:19 localhost ata2.01: ATAPI, max UDMA/33
Feb 6 21:55:19 localhost ata2.01: device is on DMA blacklist, disabling DMA
Feb 6 21:55:19 localhost ata2.00: qc timeout (cmd 0xef)
Feb 6 21:55:19 localhost ata2.00: failed to set xfermode (err_mask=0x4)
Feb 6 21:55:19 localhost ata2.00: limiting speed to UDMA/25
Feb 6 21:55:19 localhost ata2: failed to recover some devices, retrying in 5 secs
Feb 6 21:55:19 localhost ata2.01: device is on DMA blacklist, disabling DMA
Feb 6 21:55:19 localhost ata2.00: qc timeout (cmd 0xef)
Feb 6 21:55:19 localhost ata2.00: failed to set xfermode (err_mask=0x4)
Feb 6 21:55:19 localhost ata2.00: limiting speed to PIO0
Feb 6 21:55:19 localhost ata2: failed to recover some devices, retrying in 5 secs
Feb 6 21:55:19 localhost ata2.01: device is on DMA blacklist, disabling DMA
Feb 6 21:55:19 localhost ata2.00: qc timeout (cmd 0xef)
Feb 6 21:55:19 localhost ata2.00: failed to set xfermode (err_mask=0x4)
Feb 6 21:55:19 localhost ata2.00: disabled
Feb 6 21:55:19 localhost ata2: failed to recover some devices, retrying in 5 secs
Feb 6 21:55:19 localhost ata2.01: device is on DMA blacklist, disabling DMA
Feb 6 21:55:19 localhost ata2.01: failed to set xfermode (err_mask=0x40)
Feb 6 21:55:19 localhost ata2.01: limiting speed to PIO3
Feb 6 21:55:19 localhost ata2: failed to recover some devices, retrying in 5 secs
Feb 6 21:55:19 localhost ata2.01: device is on DMA blacklist, disabling DMA
Feb 6 21:55:19 localhost ata2.01: configured for PIO3
it clearly adds a lot of time to boot up, so if DMA really isn't supported for my intel 815 chipset, then what do I tell the kernel so that it doesn't waste time  checking for DMA support?
These two signs seem to be related somehow, I think.
This is all from my second hdd, that doesn't get stressed much, so I wouldn't notice a slowdown if there were one.
Last edited by vogt (2008-02-20 03:07:22)

Answer 1

Hi guys,
I havnt updated arch for a long while because last time i tried i had similar sorts of problems like above. This also happened with other distros i use with the new kernel.
If i put a cd in the cdrom drive, the problem went away and it would boot fine (it also worked if i used to ide-legacy option), but forgetting to put a cd in the drive meant a long wait so i wanted to find a fix for it.
So here i am and after a few months wait i thought there may be some changes and somebody may have fixed it. A simple solution i found was to simply add the word irqpoll to the append line in lilo, the slow boot goes away (well it did for me anyway) and problem fixed (or at least i dont have to worry about putting a cd in the drive before boot lol)
So now im back and using an up to date arch once again
Hope this helps
Kane