RE: eata irq abuse (was: Re: Linux 2.5.60)

Yes, you are correct. I used spin_unlock in order to release the local
driver lock
during the scsi_register call, but I forgot that I had the irq disabled as
well.
SO the correct fix is to use spin_unlock_irq/spin_lock_irq around the
scsi_register call. Same fix applies to the u14-34f driver.

Cheers,

*********************************
Ph.D. Dario Ballabio
EMC Computer Systems Italia spa
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*** Si vis pacem, para bellum ***

-----Original Message-----
From: Manfred Spraul [mailto:[e-mail]]
Sent: Tuesday, February 11, 2003 6:46 PM
To: Zephaniah E. Hull
Cc: [e-mail]; [e-mail];
[e-mail]
Subject: eata irq abuse (was: Re: Linux 2.5.60)

Zephaniah wrote:

>kernel BUG at mm/slab.c:1102!

Slab notices that a function that expects enabled local interrupts is called
with disabled local interrupts.

>Call Trace:
> [<c014a3b3>] do_tune_cpucache+0x83/0x240

do_tune_cpucache:
the function call smp_call_function(), and that is only permitted with
enabled local interrupts. The complain is correct.

> [<c014a300>] do_ccpupdate_local+0x0/0x30
> [<c014a5c1>] enable_cpucache+0x51/0x80
> [<c0148ea5>] kmem_cache_create+0x4a5/0x560

Within kmem_cache_create. kmem_cache_create checks for in_interrupt(), thus
someone probably does

	spin_lock_irqsave();
	kmem_cache_create();

> [<c0285dd2>] scsi_setup_command_freelist+0xa2/0x130

calls kmem_cache_create()

> [<c02887e0>] scsi_register+0x3c0/0x660

calls scsi_setup_command_freelist

> [<c02919a1>] get_pci_dev+0x31/0x50

?? probably stale

> [<c0291df2>] port_detect+0x3c2/0xe50

Do you have an eata scsi controller?

Ugs.
eata2x_detect():
* spin_lock_irqsave();
* calls port_detect();
* * spin_unlock();
* * scsi_register.

Eata maintainers: Is that necessary?
Why do the interrupts remain disabled across scsi_register?
Is that a bug workaround, or an oversight?
I'd use

	spin_unlock_irq();
	scsi_register();
	spin_lock_irq();

--
	Manfred