Not familiar with microMIPS. Not test on microMIPS.
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(-)
--
2.1.0
mm16_r5_format.rt is 5 bits, so directly judge the value if equal or not.
mm_jalr_op requires 7th to 16th bits. These 10 which bits generated by
shifting u_format.uimmediate by 6 may be affected by sign extension.
Thus, take out the 10 bits for comparison.
Without this patch, errors may occur, such as these bits are all ones.
Signed-off-by: Jinyang He <[email protected]>
---
arch/mips/kernel/process.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index 361bd28..94dfdf4 100644
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -311,8 +311,8 @@ static inline int is_jump_ins(union mips_instruction *ip)
* microMIPS is kind of more fun...
*/
if (mm_insn_16bit(ip->word >> 16)) {
- if ((ip->mm16_r5_format.opcode == mm_pool16c_op &&
- (ip->mm16_r5_format.rt & mm_jr16_op) == mm_jr16_op))
+ if (ip->mm16_r5_format.opcode == mm_pool16c_op &&
+ ip->mm16_r5_format.rt == mm_jr16_op)
return 1;
return 0;
}
@@ -324,7 +324,7 @@ static inline int is_jump_ins(union mips_instruction *ip)
if (ip->r_format.opcode != mm_pool32a_op ||
ip->r_format.func != mm_pool32axf_op)
return 0;
- return ((ip->u_format.uimmediate >> 6) & mm_jalr_op) == mm_jalr_op;
+ return ((ip->u_format.uimmediate >> 6) & GENMASK(9,0)) == mm_jalr_op;
#else
if (ip->j_format.opcode == j_op)
return 1;
--
2.1.0
?? 2021/1/12 ????8:29, Jinyang He д??:
> 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
>
> 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(-)
>
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(-)
>>