2022-03-30 11:09:57

by kernel test robot

[permalink] [raw]
Subject: [ammarfaizi2-block:google/android/kernel/common/android12-trusty-5.10 4036/5872] WARNING: modpost: vmlinux.o(.text+0x4111c4): Section mismatch in reference from the function memblock_bottom_up() to the variable .meminit.data:memblock

Hi Roman,

FYI, the error/warning still remains.

tree: https://github.com/ammarfaizi2/linux-block google/android/kernel/common/android12-trusty-5.10
head: 07055bfd3d810d41a38354693dfaa55a6f8c0025
commit: 0e0bfc41fdf4d79d39ebe929844cdee44f97366d [4036/5872] UPSTREAM: mm: cma: allocate cma areas bottom-up
config: x86_64-randconfig-a005 (https://download.01.org/0day-ci/archive/20220330/[email protected]/config)
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 0f6d9501cf49ce02937099350d08f20c4af86f3d)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/ammarfaizi2/linux-block/commit/0e0bfc41fdf4d79d39ebe929844cdee44f97366d
git remote add ammarfaizi2-block https://github.com/ammarfaizi2/linux-block
git fetch --no-tags ammarfaizi2-block google/android/kernel/common/android12-trusty-5.10
git checkout 0e0bfc41fdf4d79d39ebe929844cdee44f97366d
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <[email protected]>

All warnings (new ones prefixed by >>, old ones prefixed by <<):

>> WARNING: modpost: vmlinux.o(.text+0x4111c4): Section mismatch in reference from the function memblock_bottom_up() to the variable .meminit.data:memblock
The function memblock_bottom_up() references
the variable __meminitdata memblock.
This is often because memblock_bottom_up lacks a __meminitdata
annotation or the annotation of memblock is wrong.

--
0-DAY CI Kernel Test Service
https://01.org/lkp


2022-03-31 03:41:48

by Roman Gushchin

[permalink] [raw]
Subject: Re: [ammarfaizi2-block:google/android/kernel/common/android12-trusty-5.10 4036/5872] WARNING: modpost: vmlinux.o(.text+0x4111c4): Section mismatch in reference from the function memblock_bottom_up() to the variable .meminit.data:memblock

On Wed, Mar 30, 2022 at 02:53:14PM +0800, kbuild test robot wrote:
> Hi Roman,
>
> FYI, the error/warning still remains.
>
> tree: https://github.com/ammarfaizi2/linux-block google/android/kernel/common/android12-trusty-5.10
> head: 07055bfd3d810d41a38354693dfaa55a6f8c0025
> commit: 0e0bfc41fdf4d79d39ebe929844cdee44f97366d [4036/5872] UPSTREAM: mm: cma: allocate cma areas bottom-up
> config: x86_64-randconfig-a005 (https://download.01.org/0day-ci/archive/20220330/[email protected]/config)
> compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 0f6d9501cf49ce02937099350d08f20c4af86f3d)
> reproduce (this is a W=1 build):
> wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> chmod +x ~/bin/make.cross
> # https://github.com/ammarfaizi2/linux-block/commit/0e0bfc41fdf4d79d39ebe929844cdee44f97366d
> git remote add ammarfaizi2-block https://github.com/ammarfaizi2/linux-block
> git fetch --no-tags ammarfaizi2-block google/android/kernel/common/android12-trusty-5.10
> git checkout 0e0bfc41fdf4d79d39ebe929844cdee44f97366d
> # save the config file to linux build tree
> mkdir build_dir
> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <[email protected]>
>
> All warnings (new ones prefixed by >>, old ones prefixed by <<):
>
> >> WARNING: modpost: vmlinux.o(.text+0x4111c4): Section mismatch in reference from the function memblock_bottom_up() to the variable .meminit.data:memblock
> The function memblock_bottom_up() references
> the variable __meminitdata memblock.
> This is often because memblock_bottom_up lacks a __meminitdata
> annotation or the annotation of memblock is wrong.

I guess this patch should fix it, however I fail to reproduce the original issue.
Maybe it's up to the specific compiler version.

--

From b55a8dd19f4156d7e24ec39b18ede06965ce1c4f Mon Sep 17 00:00:00 2001
From: Roman Gushchin <[email protected]>
Date: Wed, 30 Mar 2022 14:42:12 -0700
Subject: [PATCH] memblock: fix memblock_bottom_up() and
memblock_set_bottom_up() annotations

memblock_bottom_up() and memblock_set_bottom_up() lack __meminitdata
annotations causing compiler warnings like:
WARNING: modpost: vmlinux.o(.text+0x4111c4): Section mismatch in reference from the function memblock_bottom_up() to the
variable .meminit.data:memblock

Fix it by adding the missing annotation and removing the wrong
__meminit annotation.

Reported-by: kernel test robot <[email protected]>
Signed-off-by: Roman Gushchin <[email protected]>
---
include/linux/memblock.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/linux/memblock.h b/include/linux/memblock.h
index 50ad19662a32..536bc2fc31e6 100644
--- a/include/linux/memblock.h
+++ b/include/linux/memblock.h
@@ -460,7 +460,7 @@ static inline void *memblock_alloc_node(phys_addr_t size,
/*
* Set the allocation direction to bottom-up or top-down.
*/
-static inline __init_memblock void memblock_set_bottom_up(bool enable)
+static inline __initdata_memblock void memblock_set_bottom_up(bool enable)
{
memblock.bottom_up = enable;
}
@@ -470,7 +470,7 @@ static inline __init_memblock void memblock_set_bottom_up(bool enable)
* if this is true, that said, memblock will allocate memory
* in bottom-up direction.
*/
-static inline __init_memblock bool memblock_bottom_up(void)
+static inline __initdata_memblock bool memblock_bottom_up(void)
{
return memblock.bottom_up;
}
--
2.30.2

2022-03-31 17:39:14

by Mike Rapoport

[permalink] [raw]
Subject: Re: [ammarfaizi2-block:google/android/kernel/common/android12-trusty-5.10 4036/5872] WARNING: modpost: vmlinux.o(.text+0x4111c4): Section mismatch in reference from the function memblock_bottom_up() to the variable .meminit.data:memblock

(added llvm folks)

Hi,

On Wed, Mar 30, 2022 at 02:47:43PM -0700, Roman Gushchin wrote:
> On Wed, Mar 30, 2022 at 02:53:14PM +0800, kbuild test robot wrote:
> > Hi Roman,
> >
> > FYI, the error/warning still remains.
> >
> > tree: https://github.com/ammarfaizi2/linux-block google/android/kernel/common/android12-trusty-5.10
> > head: 07055bfd3d810d41a38354693dfaa55a6f8c0025
> > commit: 0e0bfc41fdf4d79d39ebe929844cdee44f97366d [4036/5872] UPSTREAM: mm: cma: allocate cma areas bottom-up
> > config: x86_64-randconfig-a005 (https://download.01.org/0day-ci/archive/20220330/[email protected]/config)
> > compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 0f6d9501cf49ce02937099350d08f20c4af86f3d)
> > reproduce (this is a W=1 build):
> > wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> > chmod +x ~/bin/make.cross
> > # https://github.com/ammarfaizi2/linux-block/commit/0e0bfc41fdf4d79d39ebe929844cdee44f97366d
> > git remote add ammarfaizi2-block https://github.com/ammarfaizi2/linux-block
> > git fetch --no-tags ammarfaizi2-block google/android/kernel/common/android12-trusty-5.10
> > git checkout 0e0bfc41fdf4d79d39ebe929844cdee44f97366d
> > # save the config file to linux build tree
> > mkdir build_dir
> > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash
> >
> > If you fix the issue, kindly add following tag as appropriate
> > Reported-by: kernel test robot <[email protected]>
> >
> > All warnings (new ones prefixed by >>, old ones prefixed by <<):
> >
> > >> WARNING: modpost: vmlinux.o(.text+0x4111c4): Section mismatch in reference from the function memblock_bottom_up() to the variable .meminit.data:memblock
> > The function memblock_bottom_up() references
> > the variable __meminitdata memblock.
> > This is often because memblock_bottom_up lacks a __meminitdata
> > annotation or the annotation of memblock is wrong.
>
> I guess this patch should fix it, however I fail to reproduce the original issue.
> Maybe it's up to the specific compiler version.
>
> --
>
> From b55a8dd19f4156d7e24ec39b18ede06965ce1c4f Mon Sep 17 00:00:00 2001
> From: Roman Gushchin <[email protected]>
> Date: Wed, 30 Mar 2022 14:42:12 -0700
> Subject: [PATCH] memblock: fix memblock_bottom_up() and
> memblock_set_bottom_up() annotations
>
> memblock_bottom_up() and memblock_set_bottom_up() lack __meminitdata
> annotations causing compiler warnings like:
> WARNING: modpost: vmlinux.o(.text+0x4111c4): Section mismatch in reference from the function memblock_bottom_up() to the
> variable .meminit.data:memblock
>
> Fix it by adding the missing annotation and removing the wrong
> __meminit annotation.
>
> Reported-by: kernel test robot <[email protected]>
> Signed-off-by: Roman Gushchin <[email protected]>
> ---
> include/linux/memblock.h | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/include/linux/memblock.h b/include/linux/memblock.h
> index 50ad19662a32..536bc2fc31e6 100644
> --- a/include/linux/memblock.h
> +++ b/include/linux/memblock.h
> @@ -460,7 +460,7 @@ static inline void *memblock_alloc_node(phys_addr_t size,
> /*
> * Set the allocation direction to bottom-up or top-down.
> */
> -static inline __init_memblock void memblock_set_bottom_up(bool enable)
> +static inline __initdata_memblock void memblock_set_bottom_up(bool enable)

I think putting __initdata_memlock won't help here, because there should be
nothing wrong with __meminit function accessing __meminitdata data.

My guesstimate would be that the compiler decided not to inline this and
still dropped section attribute because of 'inline'.

If this is the case we I think we should

s/inline __init_memblock/__always_inline/

> {
> memblock.bottom_up = enable;
> }
> @@ -470,7 +470,7 @@ static inline __init_memblock void memblock_set_bottom_up(bool enable)
> * if this is true, that said, memblock will allocate memory
> * in bottom-up direction.
> */
> -static inline __init_memblock bool memblock_bottom_up(void)
> +static inline __initdata_memblock bool memblock_bottom_up(void)
> {
> return memblock.bottom_up;
> }
> --
> 2.30.2
>

--
Sincerely yours,
Mike.

2022-04-01 00:19:54

by Nick Desaulniers

[permalink] [raw]
Subject: Re: [ammarfaizi2-block:google/android/kernel/common/android12-trusty-5.10 4036/5872] WARNING: modpost: vmlinux.o(.text+0x4111c4): Section mismatch in reference from the function memblock_bottom_up() to the variable .meminit.data:memblock

On Thu, Mar 31, 2022 at 9:11 AM Nathan Chancellor <[email protected]> wrote:
>
> On Thu, Mar 31, 2022 at 12:42:04PM +0300, Mike Rapoport wrote:
> > (added llvm folks)
> >
> > Hi,
> >
> > On Wed, Mar 30, 2022 at 02:47:43PM -0700, Roman Gushchin wrote:
> > > On Wed, Mar 30, 2022 at 02:53:14PM +0800, kbuild test robot wrote:
> > > > Hi Roman,
> > > >
> > > > FYI, the error/warning still remains.
> > > >
> > > > tree: https://github.com/ammarfaizi2/linux-block google/android/kernel/common/android12-trusty-5.10
> > > > head: 07055bfd3d810d41a38354693dfaa55a6f8c0025
> > > > commit: 0e0bfc41fdf4d79d39ebe929844cdee44f97366d [4036/5872] UPSTREAM: mm: cma: allocate cma areas bottom-up
> > > > config: x86_64-randconfig-a005 (https://download.01.org/0day-ci/archive/20220330/[email protected]/config)
> > > > compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 0f6d9501cf49ce02937099350d08f20c4af86f3d)
> > > > reproduce (this is a W=1 build):
> > > > wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> > > > chmod +x ~/bin/make.cross
> > > > # https://github.com/ammarfaizi2/linux-block/commit/0e0bfc41fdf4d79d39ebe929844cdee44f97366d
> > > > git remote add ammarfaizi2-block https://github.com/ammarfaizi2/linux-block
> > > > git fetch --no-tags ammarfaizi2-block google/android/kernel/common/android12-trusty-5.10
> > > > git checkout 0e0bfc41fdf4d79d39ebe929844cdee44f97366d
> > > > # save the config file to linux build tree
> > > > mkdir build_dir
> > > > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash
> > > >
> > > > If you fix the issue, kindly add following tag as appropriate
> > > > Reported-by: kernel test robot <[email protected]>
> > > >
> > > > All warnings (new ones prefixed by >>, old ones prefixed by <<):
> > > >
> > > > >> WARNING: modpost: vmlinux.o(.text+0x4111c4): Section mismatch in reference from the function memblock_bottom_up() to the variable .meminit.data:memblock
> > > > The function memblock_bottom_up() references
> > > > the variable __meminitdata memblock.
> > > > This is often because memblock_bottom_up lacks a __meminitdata
> > > > annotation or the annotation of memblock is wrong.
> > >
> > > I guess this patch should fix it, however I fail to reproduce the original issue.
> > > Maybe it's up to the specific compiler version.
> > >
> > > --
> > >
> > > From b55a8dd19f4156d7e24ec39b18ede06965ce1c4f Mon Sep 17 00:00:00 2001
> > > From: Roman Gushchin <[email protected]>
> > > Date: Wed, 30 Mar 2022 14:42:12 -0700
> > > Subject: [PATCH] memblock: fix memblock_bottom_up() and
> > > memblock_set_bottom_up() annotations
> > >
> > > memblock_bottom_up() and memblock_set_bottom_up() lack __meminitdata
> > > annotations causing compiler warnings like:
> > > WARNING: modpost: vmlinux.o(.text+0x4111c4): Section mismatch in reference from the function memblock_bottom_up() to the
> > > variable .meminit.data:memblock
> > >
> > > Fix it by adding the missing annotation and removing the wrong
> > > __meminit annotation.
> > >
> > > Reported-by: kernel test robot <[email protected]>
> > > Signed-off-by: Roman Gushchin <[email protected]>
> > > ---
> > > include/linux/memblock.h | 4 ++--
> > > 1 file changed, 2 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/include/linux/memblock.h b/include/linux/memblock.h
> > > index 50ad19662a32..536bc2fc31e6 100644
> > > --- a/include/linux/memblock.h
> > > +++ b/include/linux/memblock.h
> > > @@ -460,7 +460,7 @@ static inline void *memblock_alloc_node(phys_addr_t size,
> > > /*
> > > * Set the allocation direction to bottom-up or top-down.
> > > */
> > > -static inline __init_memblock void memblock_set_bottom_up(bool enable)
> > > +static inline __initdata_memblock void memblock_set_bottom_up(bool enable)
> >
> > I think putting __initdata_memlock won't help here, because there should be
> > nothing wrong with __meminit function accessing __meminitdata data.
> >
> > My guesstimate would be that the compiler decided not to inline this and
> > still dropped section attribute because of 'inline'.
> >
> > If this is the case we I think we should
> >
> > s/inline __init_memblock/__always_inline/
> >
> > > {
> > > memblock.bottom_up = enable;
> > > }
> > > @@ -470,7 +470,7 @@ static inline __init_memblock void memblock_set_bottom_up(bool enable)
> > > * if this is true, that said, memblock will allocate memory
> > > * in bottom-up direction.
> > > */
> > > -static inline __init_memblock bool memblock_bottom_up(void)
> > > +static inline __initdata_memblock bool memblock_bottom_up(void)
> > > {
> > > return memblock.bottom_up;
> > > }
> > > --
> > > 2.30.2
> > >
> >
>
> For the record, I cannot reproduce this on mainline, which has commits
> 34dc2efb39a2 ("memblock: fix section mismatch warning") and a024b7c2850d
> ("mm: memblock: fix section mismatch warning again"). That first commit
> has the same exact warning as this report, which is against an Android
> tree (android12-trusty-5.10).
>
> While I do not see the commit that 34dc2efb39a2 claims to fix in
> android12-trusty-5.10, I do see the three commits in android12-5.10:
>
> a46e3fa13968 ("UPSTREAM: mm: memblock: drop __init from memblock functions to make it inline")
> 5f7ec0f4c383 ("UPSTREAM: memblock: fix section mismatch warning")
> 8cf5bb6946a2 ("UPSTREAM: mm: memblock: fix section mismatch warning again")

It sounds like trusty just needs to pull down from (or rebase onto)
android12-5.10 into android12-trusty-5.10.

>
> I think we can just discard this report for now, unless someone from
> Google's trusty team wants to address it in that branch.
>
> Cheers,
> Nathan



--
Thanks,
~Nick Desaulniers

2022-04-01 03:30:07

by Roman Gushchin

[permalink] [raw]
Subject: Re: [ammarfaizi2-block:google/android/kernel/common/android12-trusty-5.10 4036/5872] WARNING: modpost: vmlinux.o(.text+0x4111c4): Section mismatch in reference from the function memblock_bottom_up() to the variable .meminit.data:memblock


> On Mar 31, 2022, at 9:11 AM, Nathan Chancellor <[email protected]> wrote:
>
> On Thu, Mar 31, 2022 at 12:42:04PM +0300, Mike Rapoport wrote:
>> (added llvm folks)
>>
>> Hi,
>>
>>> On Wed, Mar 30, 2022 at 02:47:43PM -0700, Roman Gushchin wrote:
>>> On Wed, Mar 30, 2022 at 02:53:14PM +0800, kbuild test robot wrote:
>>>> Hi Roman,
>>>>
>>>> FYI, the error/warning still remains.
>>>>
>>>> tree: https://github.com/ammarfaizi2/linux-block google/android/kernel/common/android12-trusty-5.10
>>>> head: 07055bfd3d810d41a38354693dfaa55a6f8c0025
>>>> commit: 0e0bfc41fdf4d79d39ebe929844cdee44f97366d [4036/5872] UPSTREAM: mm: cma: allocate cma areas bottom-up
>>>> config: x86_64-randconfig-a005 (https://download.01.org/0day-ci/archive/20220330/[email protected]/config)
>>>> compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 0f6d9501cf49ce02937099350d08f20c4af86f3d)
>>>> reproduce (this is a W=1 build):
>>>> wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>>>> chmod +x ~/bin/make.cross
>>>> # https://github.com/ammarfaizi2/linux-block/commit/0e0bfc41fdf4d79d39ebe929844cdee44f97366d
>>>> git remote add ammarfaizi2-block https://github.com/ammarfaizi2/linux-block
>>>> git fetch --no-tags ammarfaizi2-block google/android/kernel/common/android12-trusty-5.10
>>>> git checkout 0e0bfc41fdf4d79d39ebe929844cdee44f97366d
>>>> # save the config file to linux build tree
>>>> mkdir build_dir
>>>> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash
>>>>
>>>> If you fix the issue, kindly add following tag as appropriate
>>>> Reported-by: kernel test robot <[email protected]>
>>>>
>>>> All warnings (new ones prefixed by >>, old ones prefixed by <<):
>>>>
>>>>>> WARNING: modpost: vmlinux.o(.text+0x4111c4): Section mismatch in reference from the function memblock_bottom_up() to the variable .meminit.data:memblock
>>>> The function memblock_bottom_up() references
>>>> the variable __meminitdata memblock.
>>>> This is often because memblock_bottom_up lacks a __meminitdata
>>>> annotation or the annotation of memblock is wrong.
>>>
>>> I guess this patch should fix it, however I fail to reproduce the original issue.
>>> Maybe it's up to the specific compiler version.
>>>
>>> --
>>>
>>> From b55a8dd19f4156d7e24ec39b18ede06965ce1c4f Mon Sep 17 00:00:00 2001
>>> From: Roman Gushchin <[email protected]>
>>> Date: Wed, 30 Mar 2022 14:42:12 -0700
>>> Subject: [PATCH] memblock: fix memblock_bottom_up() and
>>> memblock_set_bottom_up() annotations
>>>
>>> memblock_bottom_up() and memblock_set_bottom_up() lack __meminitdata
>>> annotations causing compiler warnings like:
>>> WARNING: modpost: vmlinux.o(.text+0x4111c4): Section mismatch in reference from the function memblock_bottom_up() to the
>>> variable .meminit.data:memblock
>>>
>>> Fix it by adding the missing annotation and removing the wrong
>>> __meminit annotation.
>>>
>>> Reported-by: kernel test robot <[email protected]>
>>> Signed-off-by: Roman Gushchin <[email protected]>
>>> ---
>>> include/linux/memblock.h | 4 ++--
>>> 1 file changed, 2 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/include/linux/memblock.h b/include/linux/memblock.h
>>> index 50ad19662a32..536bc2fc31e6 100644
>>> --- a/include/linux/memblock.h
>>> +++ b/include/linux/memblock.h
>>> @@ -460,7 +460,7 @@ static inline void *memblock_alloc_node(phys_addr_t size,
>>> /*
>>> * Set the allocation direction to bottom-up or top-down.
>>> */
>>> -static inline __init_memblock void memblock_set_bottom_up(bool enable)
>>> +static inline __initdata_memblock void memblock_set_bottom_up(bool enable)
>>
>> I think putting __initdata_memlock won't help here, because there should be
>> nothing wrong with __meminit function accessing __meminitdata data.
>>
>> My guesstimate would be that the compiler decided not to inline this and
>> still dropped section attribute because of 'inline'.
>>
>> If this is the case we I think we should
>>
>> s/inline __init_memblock/__always_inline/
>>
>>> {
>>> memblock.bottom_up = enable;
>>> }
>>> @@ -470,7 +470,7 @@ static inline __init_memblock void memblock_set_bottom_up(bool enable)
>>> * if this is true, that said, memblock will allocate memory
>>> * in bottom-up direction.
>>> */
>>> -static inline __init_memblock bool memblock_bottom_up(void)
>>> +static inline __initdata_memblock bool memblock_bottom_up(void)
>>> {
>>> return memblock.bottom_up;
>>> }
>>> --
>>> 2.30.2
>>>
>>
>
> For the record, I cannot reproduce this on mainline, which has commits
> 34dc2efb39a2 ("memblock: fix section mismatch warning") and a024b7c2850d
> ("mm: memblock: fix section mismatch warning again"). That first commit
> has the same exact warning as this report, which is against an Android
> tree (android12-trusty-5.10).
>
> While I do not see the commit that 34dc2efb39a2 claims to fix in
> android12-trusty-5.10, I do see the three commits in android12-5.10:
>
> a46e3fa13968 ("UPSTREAM: mm: memblock: drop __init from memblock functions to make it inline")
> 5f7ec0f4c383 ("UPSTREAM: memblock: fix section mismatch warning")
> 8cf5bb6946a2 ("UPSTREAM: mm: memblock: fix section mismatch warning again")
>
> I think we can just discard this report for now, unless someone from
> Google's trusty team wants to address it in that branch.

I agree. Or at least help us with the testing of the proposed fixes.

Thanks!

2022-04-01 06:40:27

by Nathan Chancellor

[permalink] [raw]
Subject: Re: [ammarfaizi2-block:google/android/kernel/common/android12-trusty-5.10 4036/5872] WARNING: modpost: vmlinux.o(.text+0x4111c4): Section mismatch in reference from the function memblock_bottom_up() to the variable .meminit.data:memblock

On Thu, Mar 31, 2022 at 12:42:04PM +0300, Mike Rapoport wrote:
> (added llvm folks)
>
> Hi,
>
> On Wed, Mar 30, 2022 at 02:47:43PM -0700, Roman Gushchin wrote:
> > On Wed, Mar 30, 2022 at 02:53:14PM +0800, kbuild test robot wrote:
> > > Hi Roman,
> > >
> > > FYI, the error/warning still remains.
> > >
> > > tree: https://github.com/ammarfaizi2/linux-block google/android/kernel/common/android12-trusty-5.10
> > > head: 07055bfd3d810d41a38354693dfaa55a6f8c0025
> > > commit: 0e0bfc41fdf4d79d39ebe929844cdee44f97366d [4036/5872] UPSTREAM: mm: cma: allocate cma areas bottom-up
> > > config: x86_64-randconfig-a005 (https://download.01.org/0day-ci/archive/20220330/[email protected]/config)
> > > compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 0f6d9501cf49ce02937099350d08f20c4af86f3d)
> > > reproduce (this is a W=1 build):
> > > wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> > > chmod +x ~/bin/make.cross
> > > # https://github.com/ammarfaizi2/linux-block/commit/0e0bfc41fdf4d79d39ebe929844cdee44f97366d
> > > git remote add ammarfaizi2-block https://github.com/ammarfaizi2/linux-block
> > > git fetch --no-tags ammarfaizi2-block google/android/kernel/common/android12-trusty-5.10
> > > git checkout 0e0bfc41fdf4d79d39ebe929844cdee44f97366d
> > > # save the config file to linux build tree
> > > mkdir build_dir
> > > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash
> > >
> > > If you fix the issue, kindly add following tag as appropriate
> > > Reported-by: kernel test robot <[email protected]>
> > >
> > > All warnings (new ones prefixed by >>, old ones prefixed by <<):
> > >
> > > >> WARNING: modpost: vmlinux.o(.text+0x4111c4): Section mismatch in reference from the function memblock_bottom_up() to the variable .meminit.data:memblock
> > > The function memblock_bottom_up() references
> > > the variable __meminitdata memblock.
> > > This is often because memblock_bottom_up lacks a __meminitdata
> > > annotation or the annotation of memblock is wrong.
> >
> > I guess this patch should fix it, however I fail to reproduce the original issue.
> > Maybe it's up to the specific compiler version.
> >
> > --
> >
> > From b55a8dd19f4156d7e24ec39b18ede06965ce1c4f Mon Sep 17 00:00:00 2001
> > From: Roman Gushchin <[email protected]>
> > Date: Wed, 30 Mar 2022 14:42:12 -0700
> > Subject: [PATCH] memblock: fix memblock_bottom_up() and
> > memblock_set_bottom_up() annotations
> >
> > memblock_bottom_up() and memblock_set_bottom_up() lack __meminitdata
> > annotations causing compiler warnings like:
> > WARNING: modpost: vmlinux.o(.text+0x4111c4): Section mismatch in reference from the function memblock_bottom_up() to the
> > variable .meminit.data:memblock
> >
> > Fix it by adding the missing annotation and removing the wrong
> > __meminit annotation.
> >
> > Reported-by: kernel test robot <[email protected]>
> > Signed-off-by: Roman Gushchin <[email protected]>
> > ---
> > include/linux/memblock.h | 4 ++--
> > 1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/include/linux/memblock.h b/include/linux/memblock.h
> > index 50ad19662a32..536bc2fc31e6 100644
> > --- a/include/linux/memblock.h
> > +++ b/include/linux/memblock.h
> > @@ -460,7 +460,7 @@ static inline void *memblock_alloc_node(phys_addr_t size,
> > /*
> > * Set the allocation direction to bottom-up or top-down.
> > */
> > -static inline __init_memblock void memblock_set_bottom_up(bool enable)
> > +static inline __initdata_memblock void memblock_set_bottom_up(bool enable)
>
> I think putting __initdata_memlock won't help here, because there should be
> nothing wrong with __meminit function accessing __meminitdata data.
>
> My guesstimate would be that the compiler decided not to inline this and
> still dropped section attribute because of 'inline'.
>
> If this is the case we I think we should
>
> s/inline __init_memblock/__always_inline/
>
> > {
> > memblock.bottom_up = enable;
> > }
> > @@ -470,7 +470,7 @@ static inline __init_memblock void memblock_set_bottom_up(bool enable)
> > * if this is true, that said, memblock will allocate memory
> > * in bottom-up direction.
> > */
> > -static inline __init_memblock bool memblock_bottom_up(void)
> > +static inline __initdata_memblock bool memblock_bottom_up(void)
> > {
> > return memblock.bottom_up;
> > }
> > --
> > 2.30.2
> >
>

For the record, I cannot reproduce this on mainline, which has commits
34dc2efb39a2 ("memblock: fix section mismatch warning") and a024b7c2850d
("mm: memblock: fix section mismatch warning again"). That first commit
has the same exact warning as this report, which is against an Android
tree (android12-trusty-5.10).

While I do not see the commit that 34dc2efb39a2 claims to fix in
android12-trusty-5.10, I do see the three commits in android12-5.10:

a46e3fa13968 ("UPSTREAM: mm: memblock: drop __init from memblock functions to make it inline")
5f7ec0f4c383 ("UPSTREAM: memblock: fix section mismatch warning")
8cf5bb6946a2 ("UPSTREAM: mm: memblock: fix section mismatch warning again")

I think we can just discard this report for now, unless someone from
Google's trusty team wants to address it in that branch.

Cheers,
Nathan