Re: [PATCH 0/4] MIPS: process: Some fixes and improvements about get_frame_info()

[Jinyang He]

On 01/18/2021 09:51 AM, Jiaxun Yang wrote:

> 在 2021/1/12 下午8:29, Jinyang He 写道:
> > Not familiar with microMIPS. Not test on microMIPS.
>
> Hi Jinyang,
>
> I was messing around QEMU microMIPS and found kernel stuck
> at loading init process after applied your patches :-(
>
> Thanks.
>
> - Jiaxun

Hi, Jiaxun,

Thanks you for test.
I think the last patch went wrong.

+    if (ip->r_format.opcode == mm_pool32a_op &&
+        ip->r_format.func == mm_pool32axf_op &&
+        ((ip->u_format.uimmediate >> 6) & GENMASK(9,0)) == mm_jalr_op &&
+            ip->r_format.rs == 31)

There is no POOL32A format in uapi/asm/inst.h, so some bits here use the
format of r_format instead.

---------------------------------------------------------------------
|    format      |  31:26  | 25:21 | 20:16 |    15:6    |    5:0 |
-----------------+---------+-------+-------+------------+------------
| pool32a_format | pool32a |  rt   |  rs   |   jalrc    | pool32axf |
-----------------+---------+-------+-------+------------+------------
|    r_format    |  opcode |  rs   |  rt   | rd:5, re:5 |    func |
---------------------------------------------------------------------

I mistakenly thought that r_format.rs and pool32a_format.rs are the same.

+        return 1;
+    return 0;

Could you help me test it again?

Thanks,
Jinyang

> > Jinyang He (4):
> >    MIPS: process: Reorder header files
> >    MIPS: microMIPS: Fix the judgment of mm_jr16_op and mm_jalr_op
> >    MIPS: Fix get_frame_info() handing of function size
> >    MIPS: Add is_jr_ra_ins() to end the loop early
> >
> >   arch/mips/kernel/process.c | 92 
> > +++++++++++++++++++++++++++++++---------------
> >   1 file changed, 62 insertions(+), 30 deletions(-)