* Re: [kernel,2.6.33-git11] lib8390: use spin_lock_irqsave for locking
@ 2010-03-07 23:22 David Miller
2010-03-08 12:24 ` Ken Kawasaki
0 siblings, 1 reply; 3+ messages in thread
From: David Miller @ 2010-03-07 23:22 UTC (permalink / raw)
To: ken_kawasaki; +Cc: netdev
This change is not correct.
disable_irq is being intentionally used because the reset
sequence can take a very long time and we don't want to
have cpu interrupts disabled during the entire sequence.
Otherwise slow serial devices will drop characters and
stuff like that.
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [kernel,2.6.33-git11] lib8390: use spin_lock_irqsave for locking
2010-03-07 23:22 [kernel,2.6.33-git11] lib8390: use spin_lock_irqsave for locking David Miller
@ 2010-03-08 12:24 ` Ken Kawasaki
2010-03-08 17:56 ` David Miller
0 siblings, 1 reply; 3+ messages in thread
From: Ken Kawasaki @ 2010-03-08 12:24 UTC (permalink / raw)
To: David Miller; +Cc: netdev
> This change is not correct.
>
> disable_irq is being intentionally used because the reset
> sequence can take a very long time and we don't want to
> have cpu interrupts disabled during the entire sequence.
>
> Otherwise slow serial devices will drop characters and
> stuff like that.
Actually, disable_irq is _not_ safe for lib8390 on SMP system.
Same CPU or other CPU can call enable_irq.
so lib8390 does not work properly on my SMP system.
Ken.
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [kernel,2.6.33-git11] lib8390: use spin_lock_irqsave for locking
2010-03-08 12:24 ` Ken Kawasaki
@ 2010-03-08 17:56 ` David Miller
0 siblings, 0 replies; 3+ messages in thread
From: David Miller @ 2010-03-08 17:56 UTC (permalink / raw)
To: ken_kawasaki; +Cc: netdev
From: Ken Kawasaki <ken_kawasaki@spring.nifty.jp>
Date: Mon, 8 Mar 2010 21:24:33 +0900
>
>> This change is not correct.
>>
>> disable_irq is being intentionally used because the reset
>> sequence can take a very long time and we don't want to
>> have cpu interrupts disabled during the entire sequence.
>>
>> Otherwise slow serial devices will drop characters and
>> stuff like that.
>
>
> Actually, disable_irq is _not_ safe for lib8390 on SMP system.
> Same CPU or other CPU can call enable_irq.
>
> so lib8390 does not work properly on my SMP system.
Then you need to fix that bug, because your patch here, again,
is not correct.
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2010-03-08 17:56 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2010-03-07 23:22 [kernel,2.6.33-git11] lib8390: use spin_lock_irqsave for locking David Miller
2010-03-08 12:24 ` Ken Kawasaki
2010-03-08 17:56 ` David Miller
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).