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From: Greg KH <gregkh@linuxfoundation.org>
To: Jens Axboe <axboe@kernel.dk>
Cc: Ming Lei <ming.lei@redhat.com>,
	linux-block@vger.kernel.org, stable@vger.kernel.org,
	Mark Ray <mark.ray@hpe.com>
Subject: Re: [PATCH] blk-mq: remove blk_mq_hw_sysfs_cpus
Date: Fri, 16 Aug 2019 16:54:35 +0200	[thread overview]
Message-ID: <20190816145435.GA3424@kroah.com> (raw)
In-Reply-To: <5baa0c28-6e12-5a61-0254-de0e49cf1596@kernel.dk>

On Fri, Aug 16, 2019 at 08:20:42AM -0600, Jens Axboe wrote:
> On 8/16/19 1:48 AM, Ming Lei wrote:
> > It is reported that sysfs buffer overflow can be triggered in case
> > of too many CPU cores(>841 on 4K PAGE_SIZE) when showing CPUs in
> > blk_mq_hw_sysfs_cpus_show().
> > 
> > This info isn't useful, given users may retrieve the CPU list
> > from sw queue entries under same kobject dir, so far not see
> > any active users.
> > 
> > So remove the entry as suggested by Greg.
> 
> I think that's a bit frivolous, there could very well be scripts or
> apps that use it. Let's just fix the overflow.

As no one really knows what the format is (and the patch to fix the
overflow changes the format of the file), I would say that it needs to
just be dropped as it is not an example of what you should be doing in
sysfs.

thanks,

greg k-h

  reply	other threads:[~2019-08-16 14:54 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-08-16  7:48 [PATCH] blk-mq: remove blk_mq_hw_sysfs_cpus Ming Lei
2019-08-16  8:12 ` Greg KH
2019-08-16 14:20 ` Jens Axboe
2019-08-16 14:54   ` Greg KH [this message]
2019-08-16 15:12     ` Jens Axboe
2019-08-16 15:21       ` Greg KH
2019-08-16 16:08   ` Ming Lei

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