From: Greg KH <gregkh@linuxfoundation.org>
To: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>,
Minchan Kim <minchan@kernel.org>,
keescook@chromium.org, dhowells@redhat.com, hch@infradead.org,
mbenes@suse.com, ngupta@vflare.org,
sergey.senozhatsky.work@gmail.com, axboe@kernel.dk,
linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
Steven Rostedt <rostedt@goodmis.org>,
Peter Zijlstra <peterz@infradead.org>,
Jessica Yu <jeyu@kernel.org>,
Thomas Gleixner <tglx@linutronix.de>,
Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH 1/2] zram: fix crashes due to use of cpu hotplug multistate
Date: Thu, 8 Apr 2021 08:18:21 +0200 [thread overview]
Message-ID: <YG6gLd9bnDsXhrNx@kroah.com> (raw)
In-Reply-To: <20210407201746.ueijmegmpbyq5quv@treble>
On Wed, Apr 07, 2021 at 03:17:46PM -0500, Josh Poimboeuf wrote:
> On Fri, Apr 02, 2021 at 09:54:12AM +0200, Greg KH wrote:
> > On Thu, Apr 01, 2021 at 11:59:25PM +0000, Luis Chamberlain wrote:
> > > As for the syfs deadlock possible with drivers, this fixes it in a generic way:
> > >
> > > commit fac43d8025727a74f80a183cc5eb74ed902a5d14
> > > Author: Luis Chamberlain <mcgrof@kernel.org>
> > > Date: Sat Mar 27 14:58:15 2021 +0000
> > >
> > > sysfs: add optional module_owner to attribute
> > >
> > > This is needed as otherwise the owner of the attribute
> > > or group read/store might have a shared lock used on driver removal,
> > > and deadlock if we race with driver removal.
> > >
> > > Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
> >
> > No, please no. Module removal is a "best effort", if the system dies
> > when it happens, that's on you. I am not willing to expend extra energy
> > and maintance of core things like sysfs for stuff like this that does
> > not matter in any system other than a developer's box.
>
> So I mentioned this on IRC, and some folks were surprised to hear that
> module unloading is unsupported and is just a development aid.
>
> Is this stance documented anywhere?
>
> If we really believe this to be true, we should make rmmod taint the
> kernel.
My throw-away comment here seems to have gotten way more attention than
it deserved, sorry about that everyone.
Nothing is supported for anything here, it's all "best effort" :)
And I would love a taint for rmmod, but what is that going to help out
with?
thanks,
greg k-h
next prev parent reply other threads:[~2021-04-08 6:18 UTC|newest]
Thread overview: 44+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-06 2:20 [PATCH 0/2] zram: fix few ltp zram02.sh crashes Luis Chamberlain
2021-03-06 2:20 ` [PATCH 1/2] zram: fix crashes due to use of cpu hotplug multistate Luis Chamberlain
2021-03-09 2:55 ` Minchan Kim
2021-03-10 13:11 ` Luis Chamberlain
2021-03-10 21:25 ` Luis Chamberlain
2021-03-12 2:08 ` Minchan Kim
2021-03-10 21:21 ` Luis Chamberlain
2021-03-12 2:14 ` Minchan Kim
2021-03-12 18:32 ` Luis Chamberlain
2021-03-12 19:28 ` Minchan Kim
2021-03-19 19:09 ` Luis Chamberlain
2021-03-22 16:37 ` Minchan Kim
2021-03-22 20:41 ` Luis Chamberlain
2021-03-22 22:12 ` Minchan Kim
2021-04-01 23:59 ` Luis Chamberlain
2021-04-02 7:54 ` Greg KH
2021-04-02 18:30 ` Luis Chamberlain
2021-04-03 6:13 ` Greg KH
[not found] ` <20210406003152.GZ4332@42.do-not-panic.com>
2021-04-06 12:00 ` Miroslav Benes
2021-04-06 15:54 ` Josh Poimboeuf
2021-04-07 14:09 ` Peter Zijlstra
2021-04-07 15:30 ` Josh Poimboeuf
2021-04-07 16:48 ` Peter Zijlstra
2021-04-07 20:17 ` Josh Poimboeuf
2021-04-08 6:18 ` Greg KH [this message]
2021-04-08 13:16 ` Steven Rostedt
2021-04-08 13:37 ` Josh Poimboeuf
2021-04-08 1:37 ` Thomas Gleixner
2021-04-08 6:16 ` Greg KH
2021-04-08 8:01 ` Jiri Kosina
2021-04-08 8:09 ` Greg KH
2021-04-08 8:35 ` Jiri Kosina
2021-04-08 8:55 ` Greg KH
2021-04-08 18:40 ` Luis Chamberlain
2021-04-09 3:01 ` Kees Cook
2021-04-05 17:07 ` Minchan Kim
2021-04-05 19:00 ` Luis Chamberlain
2021-04-05 19:58 ` Minchan Kim
2021-04-06 0:29 ` Luis Chamberlain
2021-04-07 1:23 ` Minchan Kim
2021-04-07 1:38 ` Minchan Kim
2021-04-07 14:52 ` Luis Chamberlain
2021-04-07 14:50 ` Luis Chamberlain
2021-03-06 2:20 ` [PATCH 2/2] zram: fix races of sysfs attribute removal and usage Luis Chamberlain
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