PROBLEM: 5.9.0-rc6 fails to compile due to 'redefinition of ‘dax_supported’'

PROBLEM: 5.9.0-rc6 fails to compile due to 'redefinition of ‘dax_supported’'

[Stuart Little]

I am trying to compile for an x86_64 machine (Intel(R) Core(TM) i7-7500U CPU @ 2.70GHz). The config file I am currently using is at

https://termbin.com/xin7

The build for 5.9.0-rc6 fails with the following errors:

--- cut here ---

drivers/dax/super.c:325:6: error: redefinition of ‘dax_supported’
  325 | bool dax_supported(struct dax_device *dax_dev, struct block_device *bdev,
      |      ^~~~~~~~~~~~~
In file included from drivers/dax/super.c:16:
./include/linux/dax.h:162:20: note: previous definition of ‘dax_supported’ was here
  162 | static inline bool dax_supported(struct dax_device *dax_dev,
      |                    ^~~~~~~~~~~~~
  CC      lib/memregion.o
  CC [M]  drivers/gpu/drm/drm_gem_vram_helper.o
make[2]: *** [scripts/Makefile.build:283: drivers/dax/super.o] Error 1
make[1]: *** [scripts/Makefile.build:500: drivers/dax] Error 2
make[1]: *** Waiting for unfinished jobs....

--- end ---

That's earlier on, and then later, at the end of the (failed) build:

make: *** [Makefile:1784: drivers] Error 2

The full build log is at

https://termbin.com/ihxj

but I do not see anything else amiss. 5.9.0-rc5 built fine last week.

Re: PROBLEM: 5.9.0-rc6 fails to compile due to 'redefinition of ‘dax_supported’'

[Stuart Little]

An update on this: I've done a bisect, with the following result.

--- cut here ---

e2ec5128254518cae320d5dc631b71b94160f663 is the first bad commit
commit e2ec5128254518cae320d5dc631b71b94160f663
Author: Jan Kara <jack@suse.cz>
Date:   Sun Sep 20 08:54:42 2020 -0700

    dm: Call proper helper to determine dax support
    
    DM was calling generic_fsdax_supported() to determine whether a device
    referenced in the DM table supports DAX. However this is a helper for "leaf" device drivers so that
    they don't have to duplicate common generic checks. High level code
    should call dax_supported() helper which that calls into appropriate
    helper for the particular device. This problem manifested itself as
    kernel messages:
    
    dm-3: error: dax access failed (-95)
    
    when lvm2-testsuite run in cases where a DM device was stacked on top of
    another DM device.
    
    Fixes: 7bf7eac8d648 ("dax: Arrange for dax_supported check to span multiple devices")
    Cc: <stable@vger.kernel.org>
    Tested-by: Adrian Huang <ahuang12@lenovo.com>
    Signed-off-by: Jan Kara <jack@suse.cz>
    Acked-by: Mike Snitzer <snitzer@redhat.com>
    Reported-by: kernel test robot <lkp@intel.com>
    Link: https://lore.kernel.org/r/160061715195.13131.5503173247632041975.stgit@dwillia2-desk3.amr.corp.intel.com
    Signed-off-by: Dan Williams <dan.j.williams@intel.com>

 drivers/dax/super.c   |  4 ++++
 drivers/md/dm-table.c | 10 +++++++---
 include/linux/dax.h   | 22 ++++++++++++++++++++--
 3 files changed, 31 insertions(+), 5 deletions(-)

--- end ---

On Sun, Sep 20, 2020 at 09:03:59PM -0400, Stuart Little wrote:
> I am trying to compile for an x86_64 machine (Intel(R) Core(TM) i7-7500U CPU @ 2.70GHz). The config file I am currently using is at
> 
> https://termbin.com/xin7
> 
> The build for 5.9.0-rc6 fails with the following errors:
> 
> --- cut here ---
> 
> drivers/dax/super.c:325:6: error: redefinition of ‘dax_supported’
>   325 | bool dax_supported(struct dax_device *dax_dev, struct block_device *bdev,
>       |      ^~~~~~~~~~~~~
> In file included from drivers/dax/super.c:16:
> ./include/linux/dax.h:162:20: note: previous definition of ‘dax_supported’ was here
>   162 | static inline bool dax_supported(struct dax_device *dax_dev,
>       |                    ^~~~~~~~~~~~~
>   CC      lib/memregion.o
>   CC [M]  drivers/gpu/drm/drm_gem_vram_helper.o
> make[2]: *** [scripts/Makefile.build:283: drivers/dax/super.o] Error 1
> make[1]: *** [scripts/Makefile.build:500: drivers/dax] Error 2
> make[1]: *** Waiting for unfinished jobs....
> 
> --- end ---
> 
> That's earlier on, and then later, at the end of the (failed) build:
> 
> make: *** [Makefile:1784: drivers] Error 2
> 
> The full build log is at
> 
> https://termbin.com/ihxj
> 
> but I do not see anything else amiss. 5.9.0-rc5 built fine last week.

Re: PROBLEM: 5.9.0-rc6 fails to compile due to 'redefinition of ‘dax_supported’'

[Robert Gadsdon]

On 9/20/20 7:25 PM, Stuart Little wrote:
> An update on this: I've done a bisect, with the following result.
>
> --- cut here ---
>
> e2ec5128254518cae320d5dc631b71b94160f663 is the first bad commit
> commit e2ec5128254518cae320d5dc631b71b94160f663
> Author: Jan Kara <jack@suse.cz>
> Date:   Sun Sep 20 08:54:42 2020 -0700
>
>      dm: Call proper helper to determine dax support
>      
>      DM was calling generic_fsdax_supported() to determine whether a device
>      referenced in the DM table supports DAX. However this is a helper for "leaf" device drivers so that
>      they don't have to duplicate common generic checks. High level code
>      should call dax_supported() helper which that calls into appropriate
>      helper for the particular device. This problem manifested itself as
>      kernel messages:
>      
>      dm-3: error: dax access failed (-95)
>      
>      when lvm2-testsuite run in cases where a DM device was stacked on top of
>      another DM device.
>      
>      Fixes: 7bf7eac8d648 ("dax: Arrange for dax_supported check to span multiple devices")
>      Cc: <stable@vger.kernel.org>
>      Tested-by: Adrian Huang <ahuang12@lenovo.com>
>      Signed-off-by: Jan Kara <jack@suse.cz>
>      Acked-by: Mike Snitzer <snitzer@redhat.com>
>      Reported-by: kernel test robot <lkp@intel.com>
>      Link: https://lore.kernel.org/r/160061715195.13131.5503173247632041975.stgit@dwillia2-desk3.amr.corp.intel.com
>      Signed-off-by: Dan Williams <dan.j.williams@intel.com>
>
>   drivers/dax/super.c   |  4 ++++
>   drivers/md/dm-table.c | 10 +++++++---
>   include/linux/dax.h   | 22 ++++++++++++++++++++--
>   3 files changed, 31 insertions(+), 5 deletions(-)
>
> --- end ---
>
Confirm that reverting this patch, 5.9-rc6 compiles OK ...

RG.

Re: PROBLEM: 5.9.0-rc6 fails to compile due to 'redefinition of ‘dax_supported’'

[Naresh Kamboju]

On Mon, 21 Sep 2020 at 06:34, Stuart Little <achirvasub@gmail.com> wrote:
>
> I am trying to compile for an x86_64 machine (Intel(R) Core(TM) i7-7500U CPU @ 2.70GHz). The config file I am currently using is at
>
> https://termbin.com/xin7
>
> The build for 5.9.0-rc6 fails with the following errors:
>

arm and mips allmodconfig build breaks due to this error.

>
> drivers/dax/super.c:325:6: error: redefinition of ‘dax_supported’
>   325 | bool dax_supported(struct dax_device *dax_dev, struct block_device *bdev,
>       |      ^~~~~~~~~~~~~
> In file included from drivers/dax/super.c:16:
> ./include/linux/dax.h:162:20: note: previous definition of ‘dax_supported’ was here
>   162 | static inline bool dax_supported(struct dax_device *dax_dev,
>       |                    ^~~~~~~~~~~~~
>   CC      lib/memregion.o
>   CC [M]  drivers/gpu/drm/drm_gem_vram_helper.o
> make[2]: *** [scripts/Makefile.build:283: drivers/dax/super.o] Error 1
> make[1]: *** [scripts/Makefile.build:500: drivers/dax] Error 2
> make[1]: *** Waiting for unfinished jobs....
>
> --- end ---
>
> That's earlier on, and then later, at the end of the (failed) build:
>
> make: *** [Makefile:1784: drivers] Error 2
>
> The full build log is at
>
> https://termbin.com/ihxj
>
> but I do not see anything else amiss. 5.9.0-rc5 built fine last week.

Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>

Re: PROBLEM: 5.9.0-rc6 fails to compile due to 'redefinition of ‘dax_supported’'

[Greg KH]

On Mon, Sep 21, 2020 at 11:34:17AM +0530, Naresh Kamboju wrote:
> On Mon, 21 Sep 2020 at 06:34, Stuart Little <achirvasub@gmail.com> wrote:
> >
> > I am trying to compile for an x86_64 machine (Intel(R) Core(TM) i7-7500U CPU @ 2.70GHz). The config file I am currently using is at
> >
> > https://termbin.com/xin7
> >
> > The build for 5.9.0-rc6 fails with the following errors:
> >
> 
> arm and mips allmodconfig build breaks due to this error.

all my local builds are breaking now too with this :(

Was there a proposed patch anywhere for this?

thanks,

greg k-h

Re: PROBLEM: 5.9.0-rc6 fails to compile due to 'redefinition of ‘dax_supported’'

[Borislav Petkov]

On Mon, Sep 21, 2020 at 09:32:18AM +0200, Greg KH wrote:
> all my local builds are breaking now too with this :(
> 
> Was there a proposed patch anywhere for this?

I've disabled CONFIG_BLK_DEV_PMEM which allowed me to de-select those
two:

# CONFIG_DAX is not set
# CONFIG_FS_DAX is not set

and now it at least builds.

In order to avoid such breakage in the future, I'd suggest you guys to
run randconfigs on your stuff before sending, especially if the Kconfig
ifdeffery is not a trivial one like the DAX maze.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette

Re: PROBLEM: 5.9.0-rc6 fails to compile due to 'redefinition of ‘dax_supported’'

[Bhaskar Chowdhury]

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On 09:32 Mon 21 Sep 2020, Greg KH wrote:
>On Mon, Sep 21, 2020 at 11:34:17AM +0530, Naresh Kamboju wrote:
>> On Mon, 21 Sep 2020 at 06:34, Stuart Little <achirvasub@gmail.com> wrote:
>> >
>> > I am trying to compile for an x86_64 machine (Intel(R) Core(TM) i7-7500U CPU @ 2.70GHz). The config file I am currently using is at
>> >
>> > https://termbin.com/xin7
>> >
>> > The build for 5.9.0-rc6 fails with the following errors:
>> >
>> 
>> arm and mips allmodconfig build breaks due to this error.
>
>all my local builds are breaking now too with this :(
>
>Was there a proposed patch anywhere for this?
>
>thanks,
>
>greg k-h

I don't know Greg,but it builds for me with these config :

bhaskar@Slackware_14:14:31_Mon Sep 21:~> cd /data/linux
✔ /data/linux [master|⚑ 1]
14:14 $ grep DAX .config
CONFIG_NVDIMM_DAX=y
CONFIG_DAX_DRIVER=y
CONFIG_DAX=y
CONFIG_DEV_DAX=m
CONFIG_DEV_DAX_PMEM=m
CONFIG_DEV_DAX_KMEM=m
CONFIG_DEV_DAX_PMEM_COMPAT=m
CONFIG_FS_DAX=y
CONFIG_FS_DAX_PMD=y


and it gets booted by qemu ....like this 

[    5.134563] devtmpfs: mounted
[    5.164729] Freeing unused decrypted memory: 2040K
[    5.314950] Freeing unused kernel image (initmem) memory: 1600K
[    5.316543] Write protecting the kernel read-only data: 26624k
[    5.327037] Freeing unused kernel image (text/rodata gap) memory: 2040K
[    5.331005] Freeing unused kernel image (rodata/data gap) memory: 876K
[    5.331861] rodata_test: all tests were successful
[    5.332872] Run /sbin/init as init process
[    5.694654] EXT4-fs (sda): re-mounted. Opts: (null)
[    5.695839] ext4 filesystem being remounted at / supports timestamps until 2038 (0x7fffffff)
Starting syslogd: OK
Starting klogd: OK
Running sysctl: [    6.974188] random: crng init done
OK
Initializing random number generator: OK
Saving random seed: OK
Starting network: [    8.293018] hrtimer: interrupt took 4569776 ns
OK

Welcome to Buildroot_Linux
Bhaskar_Thinkpad_x250 login: root
# uname -a
Linux Bhaskar_Thinkpad_x250 5.9.0-rc6-Slackware #1 SMP Mon Sep 21 11:42:03 IST 2020 x86_64 GNU/Linux


~Bhaskar

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Re: PROBLEM: 5.9.0-rc6 fails to compile due to 'redefinition of ‘dax_supported’'

[Jan Kara]

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On Mon 21-09-20 09:32:18, Greg KH wrote:
> On Mon, Sep 21, 2020 at 11:34:17AM +0530, Naresh Kamboju wrote:
> > On Mon, 21 Sep 2020 at 06:34, Stuart Little <achirvasub@gmail.com> wrote:
> > >
> > > I am trying to compile for an x86_64 machine (Intel(R) Core(TM) i7-7500U CPU @ 2.70GHz). The config file I am currently using is at
> > >
> > > https://termbin.com/xin7
> > >
> > > The build for 5.9.0-rc6 fails with the following errors:
> > >
> > 
> > arm and mips allmodconfig build breaks due to this error.
> 
> all my local builds are breaking now too with this :(
> 
> Was there a proposed patch anywhere for this?

Attached patch should fix the build breakage. I'm sorry for that.

								Honza
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR

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[-- Type: text/x-patch, Size: 2341 bytes --]

From 8b8c7d6148bc1bab3cf88cac49038a05db7dd938 Mon Sep 17 00:00:00 2001
From: Jan Kara <jack@suse.cz>
Date: Mon, 21 Sep 2020 11:33:23 +0200
Subject: [PATCH] dax: Fix compilation for CONFIG_DAX && !CONFIG_FS_DAX

dax_supported() is defined whenever CONFIG_DAX is enabled. So dummy
implementation should be defined only in !CONFIG_DAX case, not in
!CONFIG_FS_DAX case.

Fixes: e2ec51282545 ("dm: Call proper helper to determine dax support")
Cc: <stable@vger.kernel.org>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 include/linux/dax.h | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/include/linux/dax.h b/include/linux/dax.h
index 497031392e0a..43b39ab9de1a 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -58,6 +58,8 @@ static inline void set_dax_synchronous(struct dax_device *dax_dev)
 {
 	__set_dax_synchronous(dax_dev);
 }
+bool dax_supported(struct dax_device *dax_dev, struct block_device *bdev,
+		int blocksize, sector_t start, sector_t len);
 /*
  * Check if given mapping is supported by the file / underlying device.
  */
@@ -104,6 +106,12 @@ static inline bool dax_synchronous(struct dax_device *dax_dev)
 static inline void set_dax_synchronous(struct dax_device *dax_dev)
 {
 }
+static inline bool dax_supported(struct dax_device *dax_dev,
+		struct block_device *bdev, int blocksize, sector_t start,
+		sector_t len)
+{
+	return false;
+}
 static inline bool daxdev_mapping_supported(struct vm_area_struct *vma,
 				struct dax_device *dax_dev)
 {
@@ -130,8 +138,6 @@ static inline bool generic_fsdax_supported(struct dax_device *dax_dev,
 	return __generic_fsdax_supported(dax_dev, bdev, blocksize, start,
 			sectors);
 }
-bool dax_supported(struct dax_device *dax_dev, struct block_device *bdev,
-		int blocksize, sector_t start, sector_t len);
 
 static inline void fs_put_dax(struct dax_device *dax_dev)
 {
@@ -159,13 +165,6 @@ static inline bool generic_fsdax_supported(struct dax_device *dax_dev,
 	return false;
 }
 
-static inline bool dax_supported(struct dax_device *dax_dev,
-		struct block_device *bdev, int blocksize, sector_t start,
-		sector_t len)
-{
-	return false;
-}
-
 static inline void fs_put_dax(struct dax_device *dax_dev)
 {
 }
-- 
2.16.4

Re: PROBLEM: 5.9.0-rc6 fails to compile due to 'redefinition of ‘dax_supported’'

[Geert Uytterhoeven]

Hi Honza,

On Mon, Sep 21, 2020 at 11:54 AM Jan Kara <jack@suse.cz> wrote:
> On Mon 21-09-20 09:32:18, Greg KH wrote:
> > On Mon, Sep 21, 2020 at 11:34:17AM +0530, Naresh Kamboju wrote:
> > > On Mon, 21 Sep 2020 at 06:34, Stuart Little <achirvasub@gmail.com> wrote:
> > > > I am trying to compile for an x86_64 machine (Intel(R) Core(TM) i7-7500U CPU @ 2.70GHz). The config file I am currently using is at
> > > >
> > > > https://termbin.com/xin7
> > > >
> > > > The build for 5.9.0-rc6 fails with the following errors:
> > > >
> > >
> > > arm and mips allmodconfig build breaks due to this error.
> >
> > all my local builds are breaking now too with this :(
> >
> > Was there a proposed patch anywhere for this?
>
> Attached patch should fix the build breakage. I'm sorry for that.

Thanks, this fixes my m68k build issues:
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: PROBLEM: 5.9.0-rc6 fails to compile due to 'redefinition of ‘dax_supported’'

[Stuart Little]

Confirmed: the patch fixed the build for me as well; thank you! 

On Mon, Sep 21, 2020 at 12:08:43PM +0200, Geert Uytterhoeven wrote:
> Hi Honza,
> 
> On Mon, Sep 21, 2020 at 11:54 AM Jan Kara <jack@suse.cz> wrote:
> > On Mon 21-09-20 09:32:18, Greg KH wrote:
> > > On Mon, Sep 21, 2020 at 11:34:17AM +0530, Naresh Kamboju wrote:
> > > > On Mon, 21 Sep 2020 at 06:34, Stuart Little <achirvasub@gmail.com> wrote:
> > > > > I am trying to compile for an x86_64 machine (Intel(R) Core(TM) i7-7500U CPU @ 2.70GHz). The config file I am currently using is at
> > > > >
> > > > > https://termbin.com/xin7
> > > > >
> > > > > The build for 5.9.0-rc6 fails with the following errors:
> > > > >
> > > >
> > > > arm and mips allmodconfig build breaks due to this error.
> > >
> > > all my local builds are breaking now too with this :(
> > >
> > > Was there a proposed patch anywhere for this?
> >
> > Attached patch should fix the build breakage. I'm sorry for that.
> 
> Thanks, this fixes my m68k build issues:
> Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
> 
> Gr{oetje,eeting}s,
> 
>                         Geert
> 
> -- 
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
> 
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
>                                 -- Linus Torvalds