linux-ide.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: James Bottomley <James.Bottomley@HansenPartnership.com>
To: Dan Williams <dan.j.williams@intel.com>
Cc: linux-scsi@vger.kernel.org, linux-ide@vger.kernel.org,
	Jack Wang <jack_wang@usish.com>, Luben Tuikov <ltuikov@yahoo.com>,
	Xiangliang Yu <yuxiangl@marvell.com>
Subject: Re: [PATCH v8 08/13] libsas: libsas.force_hard_reset module parameter
Date: Wed, 29 Feb 2012 15:55:51 -0600	[thread overview]
Message-ID: <1330552551.8846.24.camel@dabdike> (raw)
In-Reply-To: <20120210084520.25701.83280.stgit@dwillia2-linux.jf.intel.com>

On Fri, 2012-02-10 at 00:45 -0800, Dan Williams wrote:
> It is possible for a host to get "locked out" from talking to sata
> devices in the domain if, for example, its sas address changes but the
> expander topology has existing affiliations with the old address.  If
> the system is booted userspace can write to
> /sys/class/sas_phy/<phy-X>/hard_reset to clear the affiliation, however
> if this condition exists for the root device the module parameter can be
> used to promote all ata resets to hard resets.

I don't quite understand this.  Are you saying we can't (or shouldn't)
execute 

/sys/class/sas_phy/<phy-X>/hard_reset

on the root device for some reason?

> After the system is booted this state can be cleared via
> /sys/module/libsas/parameters/force_hard_reset

I really don't think a module parameter for this is such a good idea ...
it effectively promotes all soft resets to being hard ones, which can
have a lot of unintended consequences.

James



  reply	other threads:[~2012-02-29 21:55 UTC|newest]

Thread overview: 29+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-02-10  8:44 [PATCH v8 00/13] libsas error handling + discovery v8 Dan Williams
2012-02-10  8:44 ` [PATCH v8 01/13] libsas: close scsi_remove_target() vs libata-eh race Dan Williams
2012-02-10 18:32   ` Jeff Garzik
2012-02-10 19:09   ` Dan Williams
2012-02-10  8:44 ` [PATCH v8 02/13] libsas: improve debug statements Dan Williams
2012-02-10  8:44 ` [PATCH v8 03/13] libsas: async ata scanning Dan Williams
2012-02-10 18:34   ` Jeff Garzik
2012-02-10  8:45 ` [PATCH v8 04/13] libsas: set attached device type and target protocols for local phys Dan Williams
2012-02-10  8:45 ` [PATCH v8 05/13] libsas: fixup target_port_protocols for expanders that don't report sata Dan Williams
2012-02-10  8:45 ` [PATCH v8 06/13] libsas: don't recover end devices attached to disabled phys Dan Williams
2012-02-10  8:45 ` [PATCH v8 07/13] scsi_transport_sas: 'enable' phys on reset Dan Williams
2012-02-10  8:45 ` [PATCH v8 08/13] libsas: libsas.force_hard_reset module parameter Dan Williams
2012-02-29 21:55   ` James Bottomley [this message]
2012-02-29 22:40     ` Douglas Gilbert
2012-02-29 23:27       ` Dan Williams
2012-03-01  0:23         ` Douglas Gilbert
2012-03-01  0:35           ` Dan Williams
2012-02-29 23:22     ` Dan Williams
2012-03-01 14:27       ` James Bottomley
2012-02-10  8:45 ` [PATCH v8 09/13] libsas: enforce eh strategy handlers only in eh context Dan Williams
2012-02-29 22:05   ` James Bottomley
2012-03-01  0:28     ` Dan Williams
2012-03-01 14:29       ` James Bottomley
2012-03-06 19:17         ` Dan Williams
2012-02-10  8:45 ` [PATCH v8 10/13] libsas: add sas_eh_abort_handler Dan Williams
2012-02-10  8:45 ` [PATCH v8 11/13] libsas: use ->lldd_I_T_nexus_reset for ->eh_bus_reset_handler Dan Williams
2012-02-10  8:45 ` [PATCH v8 12/13] isci: use sas eh strategy handlers Dan Williams
2012-02-10  8:45 ` [PATCH v8 13/13] libsas: trim sas_task of slow path infrastructure Dan Williams
2012-02-15  1:09   ` Jack Wang

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=1330552551.8846.24.camel@dabdike \
    --to=james.bottomley@hansenpartnership.com \
    --cc=dan.j.williams@intel.com \
    --cc=jack_wang@usish.com \
    --cc=linux-ide@vger.kernel.org \
    --cc=linux-scsi@vger.kernel.org \
    --cc=ltuikov@yahoo.com \
    --cc=yuxiangl@marvell.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).