kernel/sys.c: Clarify that UNAME26 does not generate unique versions anymore

b7285b42 · Jonathan Neuschäfer <[email protected]> · 2019-01-12 18:14:30 +01:00

UNAME26 is a mechanism to report Linux's version as 2.6.x, for
compatibility with old/broken software.  Due to the way it is
implemented, it would have to be updated after 5.0, to keep the
resulting versions unique.  Linus Torvalds argued:

 "Do we actually need this?

  I'd rather let it bitrot, and just let it return random versions. It
  will just start again at 2.4.60, won't it?

  Anybody who uses UNAME26 for a 5.x kernel might as well think it's
  still 4.x. The user space is so old that it can't possibly care about
  differences between 4.x and 5.x, can it?

  The only thing that matters is that it shows "2.4.<largeenough>",
  which it will do regardless"

Signed-off-by: Jonathan Neuschäfer <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

Commit: b7285b425318331c2de4af2a784a18e6dccef484
Parents: dbc3c09b

Changes

1 files changed · +2 −1

File	Status	Add	Del	Content
kernel/sys.c	modified	+2	−1	View file

kernel/sys.c

View file

diff --git a/kernel/sys.c b/kernel/sys.c
index a48cbf1..f7eb62e 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1207,7 +1207,8 @@ DECLARE_RWSEM(uts_sem);
 /*
  * Work around broken programs that cannot handle "Linux 3.0".
  * Instead we map 3.x to 2.6.40+x, so e.g. 3.0 would be 2.6.40
- * And we map 4.x to 2.6.60+x, so 4.0 would be 2.6.60.
+ * And we map 4.x and later versions to 2.6.60+x, so 4.0/5.0/6.0/... would be
+ * 2.6.60.
  */
 static int override_release(char __user *release, size_t len)
 {