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Date: Fri, 26 Jan 2024 10:58:07 -0800
From: Dan Williams <dan.j.williams@intel.com>
To: Dan Williams <dan.j.williams@intel.com>, Greg KH
	<gregkh@linuxfoundation.org>, Alistair Francis <alistair23@gmail.com>
CC: <bhelgaas@google.com>, <linux-pci@vger.kernel.org>,
	<Jonathan.Cameron@huawei.com>, <lukas@wunner.de>,
	<alex.williamson@redhat.com>, <christian.koenig@amd.com>, <kch@nvidia.com>,
	<logang@deltatee.com>, <linux-kernel@vger.kernel.org>,
	<chaitanyak@nvidia.com>, <rdunlap@infradead.org>, Alistair Francis
	<alistair.francis@wdc.com>
Subject: Re: [PATCH v6 2/3] sysfs: Add a attr_is_visible function to
 attribute_group
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Dan Williams wrote:
> Greg KH wrote:
> [..]
> > > 
> > > Hey Greg,
> > > 
> > > I wanted to follow up on this and see if you are able to provide more
> > > details for reproducing or if you are able to look into it?
> > 
> > Last I tried this, it still crashed and would not boot either on my
> > laptop or my workstation.  I don't know how it is working properly for
> > you, what systems have you tried it on?
> > 
> > I'm not going to be able to look at this for many weeks due to
> > conference stuff, so if you want to take the series and test it and
> > hopefully catch my error, that would be great, I'd love to move forward
> > and get this merged someday.
> 
> I mentioned to Lukas that I was working on a "sysfs group visibility"
> patch and he pointed me to this thread. I will note that I tried to make
> the "hide group if all attributes are invisible" approach work, but
> reverted to a "new is_group_visible() callback" approach. I did read
> through the thread and try to improve the argument in the changelog
> accordingly.
> 
> I do admit to liking the cleanliness (not touching 'struct
> attribute_group') of the "hide if no visible attribute" approch, but see
> the criticism of that alternative below, and let me know if it is
> convincing. I tested it locally with the following hack to make the
> group disappear every other sysfs_update_group() event:

Hey Greg,

Ignore this version:

---
From: Dan Williams <dan.j.williams@intel.com>
Date: Tue, 23 Jan 2024 20:20:39 -0800
Subject: [PATCH] sysfs: Introduce is_group_visible() for attribute_groups
---

I am going back to your approach without a new callback, and some fixups
to avoid unintended directory removal. I will post that shortly with its
consumer.