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Date:   Thu, 18 Aug 2022 16:25:27 +0530
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Subject: Re: [PATCH 03/16] powerpc: Fix objtool unannotated intra-function
 call warnings
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To:     Christophe Leroy <christophe.leroy@csgroup.eu>,
        Sathvika Vasireddy <sv@linux.ibm.com>,
        "linuxppc-dev@lists.ozlabs.org" <linuxppc-dev@lists.ozlabs.org>
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        "aik@ozlabs.ru" <aik@ozlabs.ru>,
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 <d3022c04-8fd5-d357-e22d-041e8f70aac8@csgroup.eu>
From:   Sathvika Vasireddy <sv@linux.vnet.ibm.com>
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On 10/08/22 14:02, Christophe Leroy wrote:
>
> Le 08/08/2022 à 13:48, Sathvika Vasireddy a écrit :
>> objtool throws unannotated intra-function call warnings
>> in the following assembly files.
>>
>> arch/powerpc/kernel/vector.o: warning: objtool: .text+0x53c: unannotated intra-function call
>>
>> arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0x60: unannotated intra-function call
>> arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0x124: unannotated intra-function call
>> arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0x5d4: unannotated intra-function call
>> arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0x5dc: unannotated intra-function call
>> arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0xcb8: unannotated intra-function call
>> arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0xd0c: unannotated intra-function call
>> arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0x1030: unannotated intra-function call
>>
>> arch/powerpc/kernel/head_64.o: warning: objtool: .text+0x358: unannotated intra-function call
>> arch/powerpc/kernel/head_64.o: warning: objtool: .text+0x728: unannotated intra-function call
>> arch/powerpc/kernel/head_64.o: warning: objtool: .text+0x4d94: unannotated intra-function call
>> arch/powerpc/kernel/head_64.o: warning: objtool: .text+0x4ec4: unannotated intra-function call
>>
>> arch/powerpc/kvm/book3s_hv_interrupts.o: warning: objtool: .text+0x6c: unannotated intra-function call
>> arch/powerpc/kernel/misc_64.o: warning: objtool: .text+0x64: unannotated intra-function call
>>
> Before explaining how you fix it, can you explain why we get it ?
Sure.

objtool does not add STT_NOTYPE symbols with size 0 to the rbtree, which 
is why find_call_destination()
function is not able to find the destination symbol for 'bl' 
instruction. For such symbols, objtool is throwing
unannotated intra-function call warnings in assembly files. Fix these 
warnings by adding
SYM_FUNC_START_LOCAL() and SYM_FUNC_END() annotations to those symbols 
to be able to set symbol
type to STT_FUNC and set size of these symbols accordingly.

I'll add this explanation to the commit message.

Thanks for reviewing.

- Sathvika