linux-kernel - Re: [PATCH 06/25] mm: factor out a devm_request_free_mem

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20190617174018.GA18185@lst.de>
Date:   Mon, 17 Jun 2019 19:40:18 +0200
From:   Christoph Hellwig <hch@....de>
To:     Dan Williams <dan.j.williams@...el.com>
Cc:     Christoph Hellwig <hch@....de>,
        Jérôme Glisse <jglisse@...hat.com>,
        Jason Gunthorpe <jgg@...lanox.com>,
        Ben Skeggs <bskeggs@...hat.com>, Linux MM <linux-mm@...ck.org>,
        nouveau@...ts.freedesktop.org,
        Maling list - DRI developers 
        <dri-devel@...ts.freedesktop.org>,
        linux-nvdimm <linux-nvdimm@...ts.01.org>,
        linux-pci@...r.kernel.org,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        John Hubbard <jhubbard@...dia.com>
Subject: Re: [PATCH 06/25] mm: factor out a devm_request_free_mem_region
 helper

On Mon, Jun 17, 2019 at 10:37:12AM -0700, Dan Williams wrote:
> > +struct resource *devm_request_free_mem_region(struct device *dev,
> > +               struct resource *base, unsigned long size);
> 
> This appears to need a 'static inline' helper stub in the
> CONFIG_DEVICE_PRIVATE=n case, otherwise this compile error triggers:
> 
> ld: mm/hmm.o: in function `hmm_devmem_add':
> /home/dwillia2/git/linux/mm/hmm.c:1427: undefined reference to
> `devm_request_free_mem_region'

*sigh* - hmm_devmem_add already only works for device private memory,
so it shouldn't be built if that option is not enabled, but in the
current code it is.  And a few patches later in the series we just
kill it off entirely, and the only real caller of this function
already depends on CONFIG_DEVICE_PRIVATE.  So I'm tempted to just
ignore the strict bisectability requirement here instead of making
things messy by either adding the proper ifdefs in hmm.c or providing
a stub we don't really need.