Merge branch 'bpf-consolidate-pointer-offset-tracking-in-var_off'

Merge branch 'bpf-consolidate-pointer-offset-tracking-in-var_off'

Eduard Zingerman says:

====================
bpf: consolidate pointer offset tracking in var_off

Consolidate static and varying pointer offset tracking logic in the
BPF verifier. All pointer offsets are now represented solely using
`reg->var_off` and min/max fields, simplifying pointer tracking code
and making it easier to widen pointer registers for loop convergence
checks.

Patch 1 is a preparatory refactoring of check_reg_sane_offset().
Patch 2 is the main change, moving pointer offsets from `reg->off`
  to `reg->var_off`.
Patch 3 removes references to `reg->off` in netronome code.
Patch 4 renames the now-repurposed `reg->off` field to `reg->delta`,
  reflecting its remaining role as a constant delta between linked
  scalar registers.

Note: netronome changes are compile-tested only!

Changelog:
v1 -> v2:
- put back WARN_ON_ONCE in mark_ptr_or_null_reg() (Alexei).
- references to `ptr->off` field are removed from netronome code
  (bot+bpf-ci, kernel test robot).
- fix for a comment referencing `ptr->off` in bpf_verifier.h
  (bot+bpf-ci).

v1: https://lore.kernel.org/bpf/20260211-ptrs-off-migration-v1-0-996c2a37b063@gmail.com/
---
====================

Link: https://patch.msgid.link/20260212-ptrs-off-migration-v2-0-00820e4d3438@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>