linux-ide.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Jeff Garzik <jgarzik@pobox.com>
To: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>,
	linux-ide@vger.kernel.org, akpm@osdl.org
Subject: Re: [PATCH] libata-core: Don't have screaming fits over DF/ERR combinations
Date: Mon, 15 Oct 2007 16:02:23 -0400	[thread overview]
Message-ID: <4713C74F.3020205@pobox.com> (raw)
In-Reply-To: <4713C549.6010704@ru.mvista.com>

Sergei Shtylyov wrote:
> Alan Cox wrote:
> 
>> Some hardware seems to get this wrong in a non-harmful way, and there are
>> some devices that seem to do it deliberately for various reasons.
> 
>> Just take it as a device error not a catastrophic state machine
>> explosion. 
> 
>> Signed-off-by: Alan Cox <alan@redhat.com>
>>
>> diff -u --exclude-from /usr/src/exclude --new-file --recursive 
>> linux.vanilla-2.6.23-mm1/drivers/ata/libata-core.c 
>> linux-2.6.23-mm1/drivers/ata/libata-core.c
>> --- linux.vanilla-2.6.23-mm1/drivers/ata/libata-core.c    2007-10-15 
>> 15:03:26.000000000 +0100
>> +++ linux-2.6.23-mm1/drivers/ata/libata-core.c    2007-10-15 
>> 15:13:49.000000000 +0100
>> @@ -5258,7 +5319,15 @@
>>          if (unlikely(status & (ATA_ERR | ATA_DF))) {
>>              ata_port_printk(ap, KERN_WARNING, "DRQ=1 with device "
>>                      "error, dev_stat 0x%X\n", status);
>> -            qc->err_mask |= AC_ERR_HSM;
>> +            /* Some devices muck this up. Some follow an ATA
>> +               non-standard that permits the damaged sector to
>> +               be retrieved at this point. The ATA spec says
>> +               we should jump up and down on DRQ + ERR, reality
> 
>    I've always thought that setting both DRQ and ERR is perfectly valid 
> (well, maybe it's become invalid since ATAPI-4 where all these state 
> transition flow charts have made its first appearance, to be quickly 
> replaced by the state diagrams :-) -- I'm too lazy to check now... :-)

DRQ+ERR is valid, and SRST (or hard reset) is defined as the method of 
kicking the device out of that state.

	Jeff




  reply	other threads:[~2007-10-15 20:02 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-10-15 18:23 [PATCH] libata-core: Don't have screaming fits over DF/ERR combinations Alan Cox
2007-10-15 19:53 ` Sergei Shtylyov
2007-10-15 20:02   ` Jeff Garzik [this message]
2007-10-15 20:05     ` Sergei Shtylyov
2007-10-15 20:09       ` Jeff Garzik
2007-10-15 20:58         ` Alan Cox
2007-10-25  6:04 ` Jeff Garzik

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=4713C74F.3020205@pobox.com \
    --to=jgarzik@pobox.com \
    --cc=akpm@osdl.org \
    --cc=alan@lxorguk.ukuu.org.uk \
    --cc=linux-ide@vger.kernel.org \
    --cc=sshtylyov@ru.mvista.com \
    /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).