diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-08-07 10:13:14 -0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-08-07 10:13:14 -0400 |
| commit | e9d488c3114acb6a0a93e99c02f9cd1d656f46c7 (patch) | |
| tree | b0342f47b8bb8fa6af3a6d1416e9881ccdb00144 /Documentation | |
| parent | 337684a1746f93ae107e05d90977b070bb7e39d8 (diff) | |
| parent | 4af75df6a410ce76d9f60f27b07e5645ecc2c5ed (diff) | |
Merge tag 'binfmt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/binfmt_misc
Pull binfmt_misc update from James Bottomley:
"This update is to allow architecture emulation containers to function
such that the emulation binary can be housed outside the container
itself. The container and fs parts both have acks from relevant
experts.
To use the new feature you have to add an F option to your binfmt_misc
configuration"
From the docs:
"The usual behaviour of binfmt_misc is to spawn the binary lazily when
the misc format file is invoked. However, this doesn't work very well
in the face of mount namespaces and changeroots, so the F mode opens
the binary as soon as the emulation is installed and uses the opened
image to spawn the emulator, meaning it is always available once
installed, regardless of how the environment changes"
* tag 'binfmt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/binfmt_misc:
binfmt_misc: add F option description to documentation
binfmt_misc: add persistent opened binary handler for containers
fs: add filp_clone_open API
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/binfmt_misc.txt | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/Documentation/binfmt_misc.txt b/Documentation/binfmt_misc.txt index 6b1de7058371..ec83bbce547a 100644 --- a/Documentation/binfmt_misc.txt +++ b/Documentation/binfmt_misc.txt @@ -66,6 +66,13 @@ Here is what the fields mean: This feature should be used with care as the interpreter will run with root permissions when a setuid binary owned by root is run with binfmt_misc. + 'F' - fix binary. The usual behaviour of binfmt_misc is to spawn the + binary lazily when the misc format file is invoked. However, + this doesn't work very well in the face of mount namespaces and + changeroots, so the F mode opens the binary as soon as the + emulation is installed and uses the opened image to spawn the + emulator, meaning it is always available once installed, + regardless of how the environment changes. There are some restrictions: |