From: Mark Lord <liml@rtr.ca>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: albertl@mail.com, albertcc@tw.ibm.com,
Tejun Heo <htejun@gmail.com>, Jeff Garzik <jeff@garzik.org>,
Linux IDE <linux-ide@vger.kernel.org>,
Doug Maxey <dwm@enoyolf.org>,
bzolnier@gmail.com
Subject: Re: [PATCH] libata: disable_irq() during polling IDENTIFY
Date: Tue, 08 May 2007 09:42:12 -0400 [thread overview]
Message-ID: <46407E34.7030800@rtr.ca> (raw)
In-Reply-To: <20070507152856.5e817490@the-village.bc.nu>
Alan Cox wrote:
>> This reminds me of a possible issue with the patch:
>> Previously the polling code assumes that the interrupt handler won't interfere
>> with it and the polling code runs without holding ap->lock.
>> However, with the above patch, the interrupt handler might read the
>> Status register when the polling code is transfering data, etc. from the port.
>> Would this cause trouble to the ATA/ATAPI devices?
>
> Oh yes, and also some controllers will corrupt their data stream if you
> do this during a PIO transfer of a block of ATA data.
I also believe that to be true, but don't know exactly which hardware
has that issue.
On the other hand, if we don't read the status from the IRQ handler,
then how does the IRQ get cleared ????
This whole thing is quite messy.
next prev parent reply other threads:[~2007-05-08 13:42 UTC|newest]
Thread overview: 52+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-05-07 4:30 [PATCH] libata: disable_irq() during polling IDENTIFY Albert Lee
2007-05-07 7:43 ` Tejun Heo
2007-05-07 11:18 ` Alan Cox
2007-05-07 11:32 ` Tejun Heo
2007-05-08 13:36 ` Mark Lord
2007-05-07 11:19 ` Albert Lee
2007-05-07 11:29 ` Tejun Heo
2007-05-07 11:54 ` Albert Lee
2007-05-07 12:01 ` Tejun Heo
2007-05-08 11:30 ` [PATCH] libata: disable_irq() during polling IDENTIFY (take 2) Albert Lee
2007-05-08 11:41 ` Tejun Heo
2007-05-08 12:00 ` Alan Cox
2007-05-08 12:01 ` Tejun Heo
2007-05-08 12:20 ` Alan Cox
2007-05-08 12:27 ` Tejun Heo
2007-05-08 12:43 ` Alan Cox
2007-05-08 12:45 ` Tejun Heo
2007-05-08 12:45 ` Alan Cox
2007-05-08 12:57 ` Tejun Heo
2007-05-08 14:59 ` Albert Lee
2007-05-08 15:16 ` Jeff Garzik
2007-05-11 7:20 ` [PATCH/RFC 0/7] libata: push part of irq driven pio to workqueue Albert Lee
2007-05-11 7:24 ` [PATCH 1/7] libata: set the state after "PIO data-in" to HSM_ST_IDLE instead of HSM_ST_LAST Albert Lee
2007-05-11 7:28 ` [PATCH 2/7] libata: move the ata_altstatus() in ata_hsm_qc_complete() Albert Lee
2007-05-11 7:30 ` [PATCH 3/7] libata: move ata_altstatus() out to the pio data xfer functions Albert Lee
2007-05-11 7:31 ` [PATCH 4/7] libata: move polling idle irq check to ata_host_intr() Albert Lee
2007-05-11 14:27 ` Tejun Heo
2007-05-11 15:25 ` Albert Lee
2007-05-11 7:35 ` [PATCH 5/7] libata: move and reduce locking to the pio data xfer functions Albert Lee
2007-05-11 14:37 ` Tejun Heo
2007-05-11 14:55 ` Alan Cox
2007-05-11 14:57 ` Tejun Heo
2007-05-11 15:12 ` Alan Cox
2007-05-11 15:14 ` Tejun Heo
2007-05-11 15:24 ` Alan Cox
2007-05-11 15:39 ` Alan Cox
2007-05-11 16:59 ` Tejun Heo
2007-05-11 17:46 ` Alan Cox
2007-05-11 17:53 ` Tejun Heo
2007-05-11 22:00 ` Alan Cox
2007-05-14 8:24 ` Tejun Heo
2007-05-14 11:29 ` Alan Cox
2007-05-11 15:48 ` Albert Lee
2007-05-11 17:06 ` Tejun Heo
2007-05-11 17:38 ` Alan Cox
2007-05-11 17:42 ` Tejun Heo
2007-05-11 17:07 ` Tejun Heo
2007-05-11 7:37 ` [PATCH 6/7] libata: push part of the irq driven pio out to workqueue Albert Lee
2007-05-11 7:41 ` [PATCH 7/7] libata: ack unexpected INTRQ when polling Albert Lee
2007-05-07 14:28 ` [PATCH] libata: disable_irq() during polling IDENTIFY Alan Cox
2007-05-08 13:42 ` Mark Lord [this message]
2007-05-08 13:57 ` Alan Cox
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=46407E34.7030800@rtr.ca \
--to=liml@rtr.ca \
--cc=alan@lxorguk.ukuu.org.uk \
--cc=albertcc@tw.ibm.com \
--cc=albertl@mail.com \
--cc=bzolnier@gmail.com \
--cc=dwm@enoyolf.org \
--cc=htejun@gmail.com \
--cc=jeff@garzik.org \
--cc=linux-ide@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
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).