Re: [PATCH 00/18] More y2038 fixes

[Joseph Myers <joseph@codesourcery.com>]

On Thu, 17 Jun 2021, Adhemerval Zanella via Libc-alpha wrote:

> > BTW: I'm wondering when the minimal, supported Linux kernel version is
> > going to be moved forward?
> 
> We usually follow the minimum LTS supported by Linux kernel developers.

However, updates are usually only done when they actually allow 
significant cleanups in glibc.  And given there isn't much benefit on 
x86_64 to increasing the minimum version, it seems like a good idea to 
first implement Carlos's proposal to remove the error at glibc startup for 
an old kernel version number (so people trying to use new glibc in 
containers on old kernels don't automatically get everything failing at 
startup, and may well have things work especially if a few syscalls have 
been backported to the old kernel).

Once Carlos's proposal is implemented, a 4.4 minimum *would* allow 
significant cleanups, such as removing most of the socketcall support.  
But it would be important to *check* the kernel support in 4.4 for each 
feature carefully before assuming it to be present globally.  (For 
example, when removing the socketcall support, we can't do so for 
getpeername or getsockname until the minimum kernel version is 4.20 or 
later (so not until 2025 based on the current EOL dates at 
<https://www.kernel.org/category/releases.html>), because that's when 
those syscalls were added to the compat syscall table for 32-bit SPARC 
programs running on 64-bit kernels.)

-- 
Joseph S. Myers
joseph@codesourcery.com