Linux CXL
 help / color / mirror / Atom feed
From: Peter Zijlstra <peterz@infradead.org>
To: Dan Williams <dan.j.williams@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>,
	linux-cxl@vger.kernel.org,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	"Rafael J. Wysocki" <rafael@kernel.org>,
	Ingo Molnar <mingo@redhat.com>, Will Deacon <will@kernel.org>,
	Waiman Long <longman@redhat.com>,
	Boqun Feng <boqun.feng@gmail.com>,
	Alison Schofield <alison.schofield@intel.com>,
	Vishal Verma <vishal.l.verma@intel.com>,
	Ben Widawsky <ben.widawsky@intel.com>,
	Jonathan Cameron <Jonathan.Cameron@huawei.com>,
	Linux NVDIMM <nvdimm@lists.linux.dev>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v3 2/8] cxl/acpi: Add root device lockdep validation
Date: Mon, 25 Apr 2022 12:33:07 +0200	[thread overview]
Message-ID: <20220425103307.GI2731@worktop.programming.kicks-ass.net> (raw)
In-Reply-To: <CAPcyv4hhD5t-qm_c_=bRjbJZFg9Mjkzbvu_2MEJB87fKy3hh-g@mail.gmail.com>

On Sat, Apr 23, 2022 at 10:27:52AM -0700, Dan Williams wrote:

> ...so I'm going to drop it and just add a comment about the
> expectations. As Peter said there's already a multitude of ways to
> cause false positive / negative results with lockdep so this is just
> one more area where one needs to be careful and understand the lock
> context they might be overriding.

One safe-guard might be to check the class you're overriding is indeed
__no_validate__, and WARN if not. Then the unconditional reset is
conistent.

Then, if/when, that WARN ever triggers you can revisit all this.

  reply	other threads:[~2022-04-25 10:33 UTC|newest]

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-04-21 15:33 [PATCH v3 0/8] device-core: Enable device_lock() lockdep validation Dan Williams
2022-04-21 15:33 ` [PATCH v3 1/8] cxl: Replace lockdep_mutex with local lock classes Dan Williams
2022-04-22 23:43   ` Ira Weiny
2022-04-21 15:33 ` [PATCH v3 2/8] cxl/acpi: Add root device lockdep validation Dan Williams
2022-04-21 16:10   ` Greg Kroah-Hartman
2022-04-22 23:58   ` Ira Weiny
2022-04-23  0:08     ` Dan Williams
2022-04-23 17:27       ` Dan Williams
2022-04-25 10:33         ` Peter Zijlstra [this message]
2022-04-25 16:05           ` Dan Williams
2022-04-25 18:57             ` Dan Williams
2022-04-23 21:05   ` [PATCH v4 " Dan Williams
2022-04-26  4:23     ` [PATCH v5 " Dan Williams
2022-04-26 19:22       ` [PATCH v6 " Dan Williams
2022-04-21 15:33 ` [PATCH v3 3/8] cxl: Drop cxl_device_lock() Dan Williams
2022-04-23  0:07   ` Ira Weiny
2022-04-21 15:33 ` [PATCH v3 4/8] nvdimm: Replace lockdep_mutex with local lock classes Dan Williams
2022-04-23  0:19   ` Ira Weiny
2022-04-21 15:33 ` [PATCH v3 5/8] ACPI: NFIT: Drop nfit_device_lock() Dan Williams
2022-04-23  0:21   ` Ira Weiny
2022-04-21 15:33 ` [PATCH v3 6/8] nvdimm: Drop nd_device_lock() Dan Williams
2022-04-23  0:24   ` Ira Weiny
2022-04-21 15:33 ` [PATCH v3 7/8] device-core: Kill the lockdep_mutex Dan Williams
2022-04-21 16:09   ` Greg Kroah-Hartman
2022-04-23  0:25   ` Ira Weiny
2022-04-21 15:33 ` [PATCH v3 8/8] nvdimm: Fix firmware activation deadlock scenarios Dan Williams
2022-04-23  4:28   ` Ira Weiny
2022-04-23 17:29     ` Dan Williams
2022-04-23 21:22   ` [PATCH v4 " Dan Williams
2022-04-24 23:30     ` Ira Weiny

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=20220425103307.GI2731@worktop.programming.kicks-ass.net \
    --to=peterz@infradead.org \
    --cc=Jonathan.Cameron@huawei.com \
    --cc=alison.schofield@intel.com \
    --cc=ben.widawsky@intel.com \
    --cc=boqun.feng@gmail.com \
    --cc=dan.j.williams@intel.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=ira.weiny@intel.com \
    --cc=linux-cxl@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=longman@redhat.com \
    --cc=mingo@redhat.com \
    --cc=nvdimm@lists.linux.dev \
    --cc=rafael@kernel.org \
    --cc=vishal.l.verma@intel.com \
    --cc=will@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