Re: [PATCH] powerpc/8xx: hide itlbie and dtlbie symbols

From: Michael Ellerman
Date: Wed Dec 12 2018 - 08:05:28 EST


Christophe Leroy <christophe.leroy@xxxxxx> writes:

> When disassembling InstructionTLBError we get the following messy code:
>
> c000138c: 7d 84 63 78 mr r4,r12
> c0001390: 75 25 58 00 andis. r5,r9,22528
> c0001394: 75 2a 40 00 andis. r10,r9,16384
> c0001398: 41 a2 00 08 beq c00013a0 <itlbie>
> c000139c: 7c 00 22 64 tlbie r4,r0
>
> c00013a0 <itlbie>:
> c00013a0: 39 40 04 01 li r10,1025
> c00013a4: 91 4b 00 b0 stw r10,176(r11)
> c00013a8: 39 40 10 32 li r10,4146
> c00013ac: 48 00 cc 59 bl c000e004 <transfer_to_handler>
>
> For a cleaner code dump, this patch replaces itlbie and dtlbie
> symbols by numeric symbols.
>
> c000138c: 7d 84 63 78 mr r4,r12
> c0001390: 75 25 58 00 andis. r5,r9,22528
> c0001394: 75 2a 40 00 andis. r10,r9,16384
> c0001398: 41 a2 00 08 beq c00013a0 <InstructionTLBError+0xa0>
> c000139c: 7c 00 22 64 tlbie r4,r0
> c00013a0: 39 40 04 01 li r10,1025
> c00013a4: 91 4b 00 b0 stw r10,176(r11)
> c00013a8: 39 40 10 32 li r10,4146
> c00013ac: 48 00 cc 59 bl c000e004 <transfer_to_handler>
> Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
> ---
> arch/powerpc/kernel/head_8xx.S | 14 ++++++--------
> 1 file changed, 6 insertions(+), 8 deletions(-)
>
> diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
> index 3b67b9533c82..8c848acfe249 100644
> --- a/arch/powerpc/kernel/head_8xx.S
> +++ b/arch/powerpc/kernel/head_8xx.S
> @@ -552,11 +552,10 @@ InstructionTLBError:
> mr r4,r12
> andis. r5,r9,DSISR_SRR1_MATCH_32S@h /* Filter relevant SRR1 bits */
> andis. r10,r9,SRR1_ISI_NOPT@h
> - beq+ 1f
> + beq+ 1301f
> tlbie r4
> -itlbie:
> /* 0x400 is InstructionAccess exception, needed by bad_page_fault() */
> -1: EXC_XFER_LITE(0x400, handle_page_fault)
> +1301: EXC_XFER_LITE(0x400, handle_page_fault)

You could use a local symbol, something like:

beq+ 1f
tlbie r4
.Litlbie:
/* 0x400 is InstructionAccess exception, needed by bad_page_fault() */
1: EXC_XFER_LITE(0x400, handle_page_fault)


cheers