Re: [BUG] ide dma_timer_expiry, then hard lockup

[Sergei Shtylyov <sshtylyov@ru.mvista.com>]

Linas Vepstas wrote:

> I've got a hard lockup in the ide subsystem, probably
> due to some irq spew or something like that.

> I've just bought a brand new Maxtor 320GB disk driver 
> for the insane price of $70 US to replace another 
> failing drive. It works well under light load;
> I was able to copy about 60GB to it. However, 
> under heavy load, such as reconstruction of an MD 
> RAID-1 array, it'll lock up the kernel.  Which means
> that my system won't boot :-(

> I'm running 2.6.21.1, although the problem seems to occur 
> in 2.6.19 and 2.6.18 too; its been there a while; I vageuly
> remember similar problems in 2.6.5 or 2.6.10.

    Ah... so you're saying that the old disk works OK, yet you've already 
observed alike behavior on other disks... That speaks against blacklisting the 
drive.

> I can get the system to boot by sneaking in an 
> "hdparm -d0 /dev/hdc" early in the boot process, to turn off 

    Could probably do the same trick and specify the lower DMA speed by using 
-X n option (where n ranges from 64 to 70 for UltraDMA modes 0 to 6) and see 
if it changes anything...

> the use of DMA, but it seems that PIO is so slow, that it takes 
> forever to get NFS started.

    You can use 'ide=nodma' kernel option for this.

MBR, Sergei