To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Cc: Bjorn Helgaas <helgaas@kernel.org>,
        kernel test robot <fengguang.wu@intel.com>,
        Linus Torvalds <torvalds@linux-foundation.org>, LKP <lkp@01.org>,
        linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org,
        linux-doc@vger.kernel.org, linux-pci@vger.kernel.org,
        linux-kernel@vger.kernel.org, Bjorn Helgaas <bhelgaas@google.com>,
        wfg@linux.intel.com, Alan Cox <alan@linux.intel.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Linus Walleij <linus.walleij@linaro.org>,
        David Airlie <airlied@linux.ie>,
        David Herrmann <dh.herrmann@gmail.com>,
        Daniel Vetter <daniel.vetter@ffwll.ch>
From: Logan Gunthorpe <logang@deltatee.com>
Message-ID: <541d1104-6139-c902-ec91-943ec1e8a881@deltatee.com>
Date: Tue, 13 Jun 2017 23:55:37 -0600
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Subject: Re: [Merge tag 'pci-v4.12-changes' of git] 857f864014: BUG: unable to
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On 13/06/17 11:00 PM, Greg Kroah-Hartman wrote:
> No, don't modify any drivers, do this in the core chardev code.

Ok, well then maybe I misunderstood what you originally asked for
because I don't see how you can change a fixed allocation to a dynamic
one without touching the driver code which needs to know the major that
was assigned in the end.

> At quick glance, looks good to me, care to clean it up and make it behind
> a config option?

Sure. However, is a config option really necessary here? As is, the
extended dynamic region will only be used if there are too many chardev
majors and it shouldn't have _any_ effect on users that have a small
number. So it seems like not selecting that option is just telling the
kernel to be broken for no obvious trade-off.

Logan