[PATCH v2 0/2] Rewrite ret_from_fork() in C

[Brian Gerst]

When kCFI is enabled, special handling is needed for the indirect call
to the kernel thread function.  Handling this in pure assembly is not
simple, so moving it to C is more appropriate.  Instead of moving just
the indirect call to C as Peter Zijlstra has proposed, this patchset
rewrites the whole ret_from_fork() function in C (other than some
necessary asm glue remaning).

V2:
- Fixed wrong address of pt_regs being passed
- Simplified 64-bit asm stub to not use a tail-call

Brian Gerst (2):
  x86/32: Remove schedule_tail_wrapper()
  x86: Rewrite ret_from_fork() in C

 arch/x86/entry/entry_32.S        | 53 ++++++++------------------------
 arch/x86/entry/entry_64.S        | 33 +++++---------------
 arch/x86/include/asm/switch_to.h |  4 ++-
 arch/x86/kernel/process.c        | 22 ++++++++++++-
 4 files changed, 45 insertions(+), 67 deletions(-)

-- 
2.41.0