All of lore.kernel.org
 help / color / mirror / Atom feed
From: "tj@kernel.org" <tj@kernel.org>
To: Bart Van Assche <Bart.VanAssche@wdc.com>
Cc: "mingo@kernel.org" <mingo@kernel.org>,
	"jthumshirn@suse.de" <jthumshirn@suse.de>,
	"oleg@redhat.com" <oleg@redhat.com>,
	"martin.petersen@oracle.com" <martin.petersen@oracle.com>,
	"stable@vger.kernel.org" <stable@vger.kernel.org>,
	"ebiederm@xmission.com" <ebiederm@xmission.com>,
	"linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>,
	"hare@suse.com" <hare@suse.com>,
	"jejb@linux.vnet.ibm.com" <jejb@linux.vnet.ibm.com>
Subject: Re: [PATCH, RESEND] Avoid that SCSI device removal through sysfs triggers a deadlock
Date: Mon, 30 Jul 2018 07:13:45 -0700	[thread overview]
Message-ID: <20180730141345.GC1206094@devbig004.ftw2.facebook.com> (raw)
In-Reply-To: <c73204ebe4ebfbbaa652a4fda910d25c9d055ce4.camel@wdc.com>

Hello, Bart.

On Thu, Jul 26, 2018 at 09:57:40PM +0000, Bart Van Assche wrote:
...
> @@ -440,11 +445,21 @@ bool sysfs_remove_file_self(struct kobject *kobj, const struct attribute *attr)
>  		return false;
>  
>  	ret = kernfs_remove_self(kn);
> +	if (ret && cb) {
> +		kernfs_break_active_protection(kn);
> +		cb(kobj, attr, data);
> +		kernfs_break_active_protection(kn);

unbreak?

Also, wouldn't it be better to just expose sysfs_break/unbreak and
then do sth like the following from scsi?

        kobject_get();
	sysfs_break_active_protection();
	do normal sysfs removal;
	sysfs_unbreak..();
	kobject_put();

Thanks.

-- 
tejun

  reply	other threads:[~2018-07-30 14:13 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-07-25 17:38 [PATCH, RESEND] Avoid that SCSI device removal through sysfs triggers a deadlock Bart Van Assche
2018-07-26  1:47 ` Martin K. Petersen
2018-07-26 11:46 ` Johannes Thumshirn
2018-07-26 11:46   ` Johannes Thumshirn
2018-07-26 12:50 ` Jack Wang
2018-07-26 13:35 ` Tejun Heo
2018-07-26 14:09   ` Bart Van Assche
2018-07-26 14:14     ` tj
2018-07-26 21:57       ` Bart Van Assche
2018-07-30 14:13         ` tj [this message]
2018-07-30 17:28           ` Bart Van Assche
2018-07-30 17:31             ` tj
2018-07-30 17:50               ` Bart Van Assche
2018-07-30 17:57                 ` tj
2018-07-29  4:03   ` Bart Van Assche
2018-07-30 14:17     ` tj

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=20180730141345.GC1206094@devbig004.ftw2.facebook.com \
    --to=tj@kernel.org \
    --cc=Bart.VanAssche@wdc.com \
    --cc=ebiederm@xmission.com \
    --cc=hare@suse.com \
    --cc=jejb@linux.vnet.ibm.com \
    --cc=jthumshirn@suse.de \
    --cc=linux-scsi@vger.kernel.org \
    --cc=martin.petersen@oracle.com \
    --cc=mingo@kernel.org \
    --cc=oleg@redhat.com \
    --cc=stable@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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.