Gentoo Archives: gentoo-user

From: Mike Gilbert <floppym@g.o>
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] /dev/shm mode 1777
Date: Sat, 04 Oct 2014 15:43:23
Message-Id: CAJ0EP41Y89dRbcO1fg5DDk=_dRQFmcVWyB6a4y4jpGmGiNLA_Q@mail.gmail.com
In Reply to: Re: [gentoo-user] /dev/shm mode 1777 by Joseph
1 On Fri, Oct 3, 2014 at 11:42 PM, Joseph <syscon780@×××××.com> wrote:
2 > On 10/03/14 23:00, Mike Gilbert wrote:
3 >>
4 >> On Fri, Oct 3, 2014 at 10:22 PM, Joseph <syscon780@×××××.com> wrote:
5 >>>
6 >>> I'm getting an error message during emerge:
7 >>> * configure has detected that the sem_open function is broken.
8 >>> * Please ensure that /dev/shm is mounted as a tmpfs with mode 1777.
9 >>> * ERROR: dev-lang/python-3.3.5-r1::gentoo failed (configure phase):
10 >>>
11 >>> my /dev/shm is mounted as drwxr-xr-x 17 root root 4020 Oct 3
12 >>> 08:57
13 >>> shm
14 >>>
15 >>> and it should be:
16 >>> drwxrwxrwt 2 root root 100 Sep 29 09:25 shm
17 >>>
18 >>> I've already change in fstab:
19 >>> from:
20 >>> shm /dev/shm devtmpfs
21 >>> nodev,nosuid,noexec
22 >>> 0 0
23 >>>
24 >>> to:
25 >>> shm /dev/shm tmpfs
26 >>> defaults,nodev,nosuid,mode=1777 0 0
27 >>>
28 >>> Is it OK to run:
29 >>> umount shm
30 >>> mount shm
31 >>>
32 >>> This is a remount system, so I want to make sure I'm not making a
33 >>> mistake.
34 >>>
35 >>
36 >> Yes, that should be fairly safe to run. The only risk is if you have
37 >> some application running which has files open on it; but umount should
38 >> give you an error in that case.
39 >>
40 >> Also, you can/should remove that fstab entry entirely once you have
41 >> remounted it; both openrc and systemd will automatically mount
42 >> /dev/shm with proper permissions if it is missing from fstab.
43 >
44 >
45 > Will it?
46 > In my kernel confg I have:
47 >
48 > grep CONFIG_DEVTMPFS /usr/src/linux/.config CONFIG_DEVTMPFS=y
49 > # CONFIG_DEVTMPFS_MOUNT is not set
50 >
51 > should I set "CONFIG_DEVTMPFS_MOUNT=y"
52 >
53
54 It has nothing to do with that kernel option.