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author | Andi Kleen <ak@linux.intel.com> | 2011-08-19 16:15:10 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-08-25 10:17:28 -0700 |
commit | be27425dcc516fd08245b047ea57f83b8f6f0903 (patch) | |
tree | 0f7cfb258a663d99ebeedf8ed3b9637b266b021c /include | |
parent | caca9510ff4e5d842c0589110243d60927836222 (diff) | |
download | lwn-be27425dcc516fd08245b047ea57f83b8f6f0903.tar.gz lwn-be27425dcc516fd08245b047ea57f83b8f6f0903.zip |
Add a personality to report 2.6.x version numbers
I ran into a couple of programs which broke with the new Linux 3.0
version. Some of those were binary only. I tried to use LD_PRELOAD to
work around it, but it was quite difficult and in one case impossible
because of a mix of 32bit and 64bit executables.
For example, all kind of management software from HP doesnt work, unless
we pretend to run a 2.6 kernel.
$ uname -a
Linux svivoipvnx001 3.0.0-08107-g97cd98f #1062 SMP Fri Aug 12 18:11:45 CEST 2011 i686 i686 i386 GNU/Linux
$ hpacucli ctrl all show
Error: No controllers detected.
$ rpm -qf /usr/sbin/hpacucli
hpacucli-8.75-12.0
Another notable case is that Python now reports "linux3" from
sys.platform(); which in turn can break things that were checking
sys.platform() == "linux2":
https://bugzilla.mozilla.org/show_bug.cgi?id=664564
It seems pretty clear to me though it's a bug in the apps that are using
'==' instead of .startswith(), but this allows us to unbreak broken
programs.
This patch adds a UNAME26 personality that makes the kernel report a
2.6.40+x version number instead. The x is the x in 3.x.
I know this is somewhat ugly, but I didn't find a better workaround, and
compatibility to existing programs is important.
Some programs also read /proc/sys/kernel/osrelease. This can be worked
around in user space with mount --bind (and a mount namespace)
To use:
wget ftp://ftp.kernel.org/pub/linux/kernel/people/ak/uname26/uname26.c
gcc -o uname26 uname26.c
./uname26 program
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/personality.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/linux/personality.h b/include/linux/personality.h index eec3bae164d4..8fc7dd1a57ff 100644 --- a/include/linux/personality.h +++ b/include/linux/personality.h @@ -22,6 +22,7 @@ extern int __set_personality(unsigned int); * These occupy the top three bytes. */ enum { + UNAME26 = 0x0020000, ADDR_NO_RANDOMIZE = 0x0040000, /* disable randomization of VA space */ FDPIC_FUNCPTRS = 0x0080000, /* userspace function ptrs point to descriptors * (signal handling) |