Re: [PATCH v4 3/9] x86/entry: Convert ret_from_fork to C

[Josh Poimboeuf]

On Wed, Mar 17, 2021 at 11:12:42AM -0700, Andy Lutomirski wrote:
> ret_from_fork is written in asm, slightly differently, for x86_32 and
> x86_64.  Convert it to C.
> 
> This is a straight conversion without any particular cleverness.  As a
> further cleanup, the code that sets up the ret_from_fork argument registers
> could be adjusted to put the arguments in the correct registers.
> 
> This will cause the ORC unwinder to find pt_regs even for kernel threads on
> x86_64.  This seems harmless.
> 
> The 32-bit comment above the now-deleted schedule_tail_wrapper was
> obsolete: the encode_frame_pointer mechanism (see copy_thread()) solves the
> same problem more cleanly.
> 
> Cc: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
> Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxx>

Acked-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>

-- 
Josh