Re: [PATCH] fs: fix sysctls.c built

From: Luis Chamberlain <mcgrof@kernel.org>
To: Christian Brauner <brauner@kernel.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>,
	linux-fsdevel@vger.kernel.org,
	Andrew Morton <akpm@linux-foundation.org>,
	linux-kernel@vger.kernel.org,
	Alexander Viro <viro@zeniv.linux.org.uk>
Subject: Re: [PATCH] fs: fix sysctls.c built
Date: Thu, 13 Apr 2023 10:06:35 -0700	[thread overview]
Message-ID: <ZDg2m/U1NasHfK4j@bombadil.infradead.org> (raw)
In-Reply-To: <20230412-sympathie-haltbar-da2d2183067b@brauner>

On Wed, Apr 12, 2023 at 11:19:56AM +0200, Christian Brauner wrote:
> On Tue, Apr 11, 2023 at 12:14:44PM +0800, Kefeng Wang wrote:
> > /proc/sys/fs/overflowuid and overflowgid  will be lost without
> > building this file, kindly ping, any comments, thanks.
> > 
> > 
> > On 2023/3/31 16:45, Kefeng Wang wrote:
> > > 'obj-$(CONFIG_SYSCTL) += sysctls.o' must be moved after "obj-y :=",
> > > or it won't be built as it is overwrited.
> > > 
> > > Fixes: ab171b952c6e ("fs: move namespace sysctls and declare fs base directory")
> > > Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
> > > ---
> > >   fs/Makefile | 3 +--
> > >   1 file changed, 1 insertion(+), 2 deletions(-)
> > > 
> > > diff --git a/fs/Makefile b/fs/Makefile
> > > index 05f89b5c962f..8d4736fcc766 100644
> > > --- a/fs/Makefile
> > > +++ b/fs/Makefile
> > > @@ -6,7 +6,6 @@
> > >   # Rewritten to use lists instead of if-statements.
> > >   #
> > > -obj-$(CONFIG_SYSCTL)		+= sysctls.o
> > >   obj-y :=	open.o read_write.o file_table.o super.o \
> > >   		char_dev.o stat.o exec.o pipe.o namei.o fcntl.o \
> > > @@ -50,7 +49,7 @@ obj-$(CONFIG_FS_MBCACHE)	+= mbcache.o
> > >   obj-$(CONFIG_FS_POSIX_ACL)	+= posix_acl.o
> > >   obj-$(CONFIG_NFS_COMMON)	+= nfs_common/
> > >   obj-$(CONFIG_COREDUMP)		+= coredump.o
> > > -obj-$(CONFIG_SYSCTL)		+= drop_caches.o
> > > +obj-$(CONFIG_SYSCTL)		+= drop_caches.o sysctls.o
> > >   obj-$(CONFIG_FHANDLE)		+= fhandle.o
> > >   obj-y				+= iomap/
> 
> Given the description in
> ab171b952c6e ("fs: move namespace sysctls and declare fs base directory")
> you probably want to move this earlier.

I was being *way* too cautious and I was wrong, so I'll take Kefang's patch as
I can verify now that order does not matter and his patch is correct.
I've corrected the documentation and clarified this on sysctl-next and
so reflected on linux-next too with these two patches:

sysctl: clarify register_sysctl_init() base directory order
https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux.git/commit/?h=sysctl-next-20230413&id=8ae59580f2b0529b6dd1a1cda6b838cfb268cb87

proc_sysctl: move helper which creates required subdirectories
https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux.git/commit/?h=sysctl-next-20230413&id=f4c09b14073513efd581459520a01c4c88cb24d7

proc_sysctl: update docs for __register_sysctl_table()
https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux.git/commit/?h=sysctl-next-20230413&id=d59d91edd67ec4cef62f26249510fe08b291ae72

proc_sysctl: enhance documentation
https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux.git/commit/?h=sysctl-next-20230413&id=eb472aa0678fd03321093bffeb9c7fd7f5035844

And so something we can do eventually is do away with all the base stuff.
For now it's fine, it's not creating an issue.

  Luis