Re: linux-next: manual merge of the akpm-current tree with the powerpc tree

[Christophe Leroy <christophe.leroy@csgroup.eu>]

Le 15/04/2021 à 12:07, Christophe Leroy a écrit :
> 
> 
> Le 15/04/2021 à 11:58, Stephen Rothwell a écrit :
>> Hi all,
>>
>> On Thu, 15 Apr 2021 19:44:17 +1000 Stephen Rothwell <sfr@canb.auug.org.au> wrote:
>>>
>>> Today's linux-next merge of the akpm-current tree got a conflict in:
>>>
>>>    arch/powerpc/kernel/module.c
>>>
>>> between commit:
>>>
>>>    2ec13df16704 ("powerpc/modules: Load modules closer to kernel text")
>>>
>>> from the powerpc tree and commit:
>>>
>>>    4930ba789f8d ("powerpc/64s/radix: enable huge vmalloc mappings")
>>>
>>> from the akpm-current tree.
>>>
>>> I fixed it up (I think - see below) and can carry the fix as
>>> necessary. This is now fixed as far as linux-next is concerned, but any
>>> non trivial conflicts should be mentioned to your upstream maintainer
>>> when your tree is submitted for merging.  You may also want to consider
>>> cooperating with the maintainer of the conflicting tree to minimise any
>>> particularly complex conflicts.
>>>
>>> -- 
>>> Cheers,
>>> Stephen Rothwell
>>>
>>> diff --cc arch/powerpc/kernel/module.c
>>> index fab84024650c,cdb2d88c54e7..000000000000
>>> --- a/arch/powerpc/kernel/module.c
>>> +++ b/arch/powerpc/kernel/module.c
>>> @@@ -88,29 -88,26 +89,42 @@@ int module_finalize(const Elf_Ehdr *hdr
>>>        return 0;
>>>    }
>>> - #ifdef MODULES_VADDR
>>>   -void *module_alloc(unsigned long size)
>>>   +static __always_inline void *
>>>   +__module_alloc(unsigned long size, unsigned long start, unsigned long end)
>>>    {
>>>   -    unsigned long start = VMALLOC_START;
>>>   -    unsigned long end = VMALLOC_END;
>>>   -
>>>   -#ifdef MODULES_VADDR
>>>   -    BUILD_BUG_ON(TASK_SIZE > MODULES_VADDR);
>>>   -    start = MODULES_VADDR;
>>>   -    end = MODULES_END;
>>>   -#endif
>>>   -
>>> +     /*
>>> +      * Don't do huge page allocations for modules yet until more testing
>>> +      * is done. STRICT_MODULE_RWX may require extra work to support this
>>> +      * too.
>>> +      */
>>> +
>>>        return __vmalloc_node_range(size, 1, start, end, GFP_KERNEL,
>>> -                     PAGE_KERNEL_EXEC, VM_FLUSH_RESET_PERMS, NUMA_NO_NODE,
>>> +                     PAGE_KERNEL_EXEC,
>>> +                     VM_NO_HUGE_VMAP | VM_FLUSH_RESET_PERMS,
>>> +                     NUMA_NO_NODE,
>>>                        __builtin_return_address(0));
>>>    }
>>>   +
>>> ++
>>>   +void *module_alloc(unsigned long size)
>>>   +{
>>> ++    unsigned long start = VMALLOC_START;
>>> ++    unsigned long end = VMALLOC_END;
>>>   +    unsigned long limit = (unsigned long)_etext - SZ_32M;
>>>   +    void *ptr = NULL;
>>>   +
>>> ++#ifdef MODULES_VADDR
>>>   +    BUILD_BUG_ON(TASK_SIZE > MODULES_VADDR);
>>> ++    start = MODULES_VADDR;
>>> ++    end = MODULES_END;
> 
> The #endif should be here.
> 
> 
>>>   +
>>>   +    /* First try within 32M limit from _etext to avoid branch trampolines */
>>>   +    if (MODULES_VADDR < PAGE_OFFSET && MODULES_END > limit)

Should also use start and end here instead of MODULES_VADDR  and MODULES_END

>>> -         ptr = __module_alloc(size, limit, MODULES_END);
>>> ++        ptr = __module_alloc(size, limit, end);
>>>   +
>>>   +    if (!ptr)
>>> -         ptr = __module_alloc(size, MODULES_VADDR, MODULES_END);
>>> ++#endif
>>> ++        ptr = __module_alloc(size, start, end);
>>>   +
>>>   +    return ptr;
>>>   +}
>>> - #endif
>>
>> Unfortunately, it also needs this:
> 
> Before the #endif is too far.
> 
>>
>> From: Stephen Rothwell <sfr@canb.auug.org.au>
>> Date: Thu, 15 Apr 2021 19:53:58 +1000
>> Subject: [PATCH] merge fix up for powerpc merge fix
>>
>> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
>> ---
>>   arch/powerpc/kernel/module.c | 2 ++
>>   1 file changed, 2 insertions(+)
>>
>> diff --git a/arch/powerpc/kernel/module.c b/arch/powerpc/kernel/module.c
>> index d8ab1ad2eb05..c060f99afd4d 100644
>> --- a/arch/powerpc/kernel/module.c
>> +++ b/arch/powerpc/kernel/module.c
>> @@ -110,7 +110,9 @@ void *module_alloc(unsigned long size)
>>   {
>>       unsigned long start = VMALLOC_START;
>>       unsigned long end = VMALLOC_END;
>> +#ifdef MODULES_VADDR
>>       unsigned long limit = (unsigned long)_etext - SZ_32M;
>> +#endif
>>       void *ptr = NULL;
>>   #ifdef MODULES_VADDR
>>