[bigeasy-staging:lockdep-nesting 7/12] include/linux/fs.h:1422:29: error: array type has incomplete element type 'struct percpu_rw_semaphore'

[bigeasy-staging:lockdep-nesting 7/12] include/linux/fs.h:1422:29: error: array type has incomplete element type 'struct percpu_rw_semaphore'

[kbuild test robot]

[-- Attachment #1: Type: text/plain, Size: 2445 bytes --]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/bigeasy/staging.git lockdep-nesting
head:   6fc4f4da69e0935e367236eea81e979b1a72c5b4
commit: 27e1b50f54aaaa88fd9b0040ce0d8285c584410e [7/12] rcuwait: Add @state argument to rcuwait_wait_event()
config: ia64-allmodconfig (attached as .config)
compiler: ia64-linux-gcc (GCC) 9.2.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        git checkout 27e1b50f54aaaa88fd9b0040ce0d8285c584410e
        # save the attached .config to linux build tree
        GCC_VERSION=9.2.0 make.cross ARCH=ia64 

If you fix the issue, kindly add following tag
Reported-by: kbuild test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   In file included from include/linux/huge_mm.h:8,
                    from include/linux/mm.h:567,
                    from arch/ia64/include/asm/uaccess.h:38,
                    from include/linux/uaccess.h:11,
                    from include/linux/sched/task.h:11,
                    from include/linux/sched/signal.h:9,
                    from include/linux/rcuwait.h:6,
                    from include/linux/percpu-rwsem.h:8,
                    from kernel/locking/percpu-rwsem.c:6:
>> include/linux/fs.h:1422:29: error: array type has incomplete element type 'struct percpu_rw_semaphore'
    1422 |  struct percpu_rw_semaphore rw_sem[SB_FREEZE_LEVELS];
         |                             ^~~~~~

vim +1422 include/linux/fs.h

5accdf82ba25ca Jan Kara      2012-06-12  1418  
5accdf82ba25ca Jan Kara      2012-06-12  1419  struct sb_writers {
5accdf82ba25ca Jan Kara      2012-06-12  1420  	int				frozen;		/* Is sb frozen? */
8129ed29644bf5 Oleg Nesterov 2015-08-11  1421  	wait_queue_head_t		wait_unfrozen;	/* for get_super_thawed() */
8129ed29644bf5 Oleg Nesterov 2015-08-11 @1422  	struct percpu_rw_semaphore	rw_sem[SB_FREEZE_LEVELS];
5accdf82ba25ca Jan Kara      2012-06-12  1423  };
5accdf82ba25ca Jan Kara      2012-06-12  1424  

:::::: The code at line 1422 was first introduced by commit
:::::: 8129ed29644bf56ed17ec1bbbeed5c568b43d6a0 change sb_writers to use percpu_rw_semaphore

:::::: TO: Oleg Nesterov <oleg@redhat.com>
:::::: CC: Oleg Nesterov <oleg@redhat.com>

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org

[-- Attachment #2: config.gz --]
[-- Type: application/gzip, Size: 56555 bytes --]

Re: [bigeasy-staging:lockdep-nesting 7/12] include/linux/fs.h:1422:29: error: array type has incomplete element type 'struct percpu_rw_semaphore'

[Sebastian Andrzej Siewior]

[-- Attachment #1: Type: text/plain, Size: 1192 bytes --]

On 2020-03-19 17:17:37 [+0800], kbuild test robot wrote:
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/bigeasy/staging.git lockdep-nesting
> head:   6fc4f4da69e0935e367236eea81e979b1a72c5b4

This is the new HEAD. New as in tglx's v2 with the removal of the mm.h
include in nds32. And we have the same issue

> commit: 27e1b50f54aaaa88fd9b0040ce0d8285c584410e [7/12] rcuwait: Add @state argument to rcuwait_wait_event()
> config: ia64-allmodconfig (attached as .config)
> compiler: ia64-linux-gcc (GCC) 9.2.0
> reproduce:
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         git checkout 27e1b50f54aaaa88fd9b0040ce0d8285c584410e
>         # save the attached .config to linux build tree
>         GCC_VERSION=9.2.0 make.cross ARCH=ia64 

on ia64. And probably on

|$ git grep linux/mm.h arch/*/include/asm/uaccess.h
|arch/csky/include/asm/uaccess.h:#include <linux/mm.h>
|arch/hexagon/include/asm/uaccess.h:#include <linux/mm.h>
|arch/ia64/include/asm/uaccess.h:#include <linux/mm.h>
|arch/microblaze/include/asm/uaccess.h:#include <linux/mm.h>

Sebastian

[PATCH 0/5] Remove mm.h from arch/*/include/asm/uaccess.h

[Sebastian Andrzej Siewior]

[-- Attachment #1: Type: text/plain, Size: 336 bytes --]

The following mini-series removes linux/mm.h from the asm/uaccess.h of
the individual architecture. The series has been compile tested with the
defconfig and additionally for ia64 with the "special" allmodconfig
supplied by the bot. The regular allmod for the architectures does not
compile (even without the series).

Sebastian

[PATCH 1/5] nds32: Remove mm.h from asm/uaccess.h

[Sebastian Andrzej Siewior]

[-- Attachment #1: Type: text/plain, Size: 1492 bytes --]

The defconfig compiles without linux/mm.h. With mm.h included the
include chain leands to:
|   CC      kernel/locking/percpu-rwsem.o
| In file included from include/linux/huge_mm.h:8,
|                  from include/linux/mm.h:567,
|                  from arch/nds32/include/asm/uaccess.h:,
|                  from include/linux/uaccess.h:11,
|                  from include/linux/sched/task.h:11,
|                  from include/linux/sched/signal.h:9,
|                  from include/linux/rcuwait.h:6,
|                  from include/linux/percpu-rwsem.h:8,
|                  from kernel/locking/percpu-rwsem.c:6:
| include/linux/fs.h:1422:29: error: array type has incomplete element type 'struct percpu_rw_semaphore'
|  1422 |  struct percpu_rw_semaphore rw_sem[SB_FREEZE_LEVELS];

once rcuwait.h includes linux/sched/signal.h.

Remove the linux/mm.h include.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 arch/nds32/include/asm/uaccess.h | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/nds32/include/asm/uaccess.h b/arch/nds32/include/asm/uaccess.h
index 8916ad9f9f139..3a9219f53ee0d 100644
--- a/arch/nds32/include/asm/uaccess.h
+++ b/arch/nds32/include/asm/uaccess.h
@@ -11,7 +11,6 @@
 #include <asm/errno.h>
 #include <asm/memory.h>
 #include <asm/types.h>
-#include <linux/mm.h>
 
 #define __asmeq(x, y)  ".ifnc " x "," y " ; .err ; .endif\n\t"
 
-- 
2.26.0.rc2

[PATCH 2/5] csky: Remove mm.h from asm/uaccess.h

[Sebastian Andrzej Siewior]

[-- Attachment #1: Type: text/plain, Size: 1504 bytes --]

The defconfig compiles without linux/mm.h. With mm.h included the
include chain leands to:
|   CC      kernel/locking/percpu-rwsem.o
| In file included from include/linux/huge_mm.h:8,
|                  from include/linux/mm.h:567,
|                  from arch/csky/include/asm/uaccess.h:,
|                  from include/linux/uaccess.h:11,
|                  from include/linux/sched/task.h:11,
|                  from include/linux/sched/signal.h:9,
|                  from include/linux/rcuwait.h:6,
|                  from include/linux/percpu-rwsem.h:8,
|                  from kernel/locking/percpu-rwsem.c:6:
| include/linux/fs.h:1422:29: error: array type has incomplete element type 'struct percpu_rw_semaphore'
|  1422 |  struct percpu_rw_semaphore rw_sem[SB_FREEZE_LEVELS];

once rcuwait.h includes linux/sched/signal.h.

Remove the linux/mm.h include.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 arch/csky/include/asm/uaccess.h | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/csky/include/asm/uaccess.h b/arch/csky/include/asm/uaccess.h
index eaa1c3403a424..abefa125b93cf 100644
--- a/arch/csky/include/asm/uaccess.h
+++ b/arch/csky/include/asm/uaccess.h
@@ -11,7 +11,6 @@
 #include <linux/errno.h>
 #include <linux/types.h>
 #include <linux/sched.h>
-#include <linux/mm.h>
 #include <linux/string.h>
 #include <linux/version.h>
 #include <asm/segment.h>
-- 
2.26.0.rc2

[PATCH 3/5] hexagon: Remove mm.h from asm/uaccess.h

[Sebastian Andrzej Siewior]

[-- Attachment #1: Type: text/plain, Size: 1444 bytes --]

The defconfig compiles without linux/mm.h. With mm.h included the
include chain leands to:
|   CC      kernel/locking/percpu-rwsem.o
| In file included from include/linux/huge_mm.h:8,
|                  from include/linux/mm.h:567,
|                  from arch/hexagon/include/asm/uaccess.h:,
|                  from include/linux/uaccess.h:11,
|                  from include/linux/sched/task.h:11,
|                  from include/linux/sched/signal.h:9,
|                  from include/linux/rcuwait.h:6,
|                  from include/linux/percpu-rwsem.h:8,
|                  from kernel/locking/percpu-rwsem.c:6:
| include/linux/fs.h:1422:29: error: array type has incomplete element type 'struct percpu_rw_semaphore'
|  1422 |  struct percpu_rw_semaphore rw_sem[SB_FREEZE_LEVELS];

once rcuwait.h includes linux/sched/signal.h.

Remove the linux/mm.h include.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 arch/hexagon/include/asm/uaccess.h | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/hexagon/include/asm/uaccess.h b/arch/hexagon/include/asm/uaccess.h
index 00cb38faad0c4..c1019a736ff13 100644
--- a/arch/hexagon/include/asm/uaccess.h
+++ b/arch/hexagon/include/asm/uaccess.h
@@ -10,7 +10,6 @@
 /*
  * User space memory access functions
  */
-#include <linux/mm.h>
 #include <asm/sections.h>
 
 /*
-- 
2.26.0.rc2

[PATCH 4/5] ia64: Remove mm.h from asm/uaccess.h

[Sebastian Andrzej Siewior]

[-- Attachment #1: Type: text/plain, Size: 2210 bytes --]

The defconfig compiles without linux/mm.h. With mm.h included the
include chain leands to:
|   CC      kernel/locking/percpu-rwsem.o
| In file included from include/linux/huge_mm.h:8,
|                  from include/linux/mm.h:567,
|                  from arch/ia64/include/asm/uaccess.h:,
|                  from include/linux/uaccess.h:11,
|                  from include/linux/sched/task.h:11,
|                  from include/linux/sched/signal.h:9,
|                  from include/linux/rcuwait.h:6,
|                  from include/linux/percpu-rwsem.h:8,
|                  from kernel/locking/percpu-rwsem.c:6:
| include/linux/fs.h:1422:29: error: array type has incomplete element type 'struct percpu_rw_semaphore'
|  1422 |  struct percpu_rw_semaphore rw_sem[SB_FREEZE_LEVELS];

once rcuwait.h includes linux/sched/signal.h.

Remove the linux/mm.h include.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 arch/ia64/include/asm/uaccess.h | 1 -
 arch/ia64/kernel/process.c      | 1 +
 arch/ia64/mm/ioremap.c          | 1 +
 3 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/ia64/include/asm/uaccess.h b/arch/ia64/include/asm/uaccess.h
index 89782ad3fb887..5c7e79eccaeed 100644
--- a/arch/ia64/include/asm/uaccess.h
+++ b/arch/ia64/include/asm/uaccess.h
@@ -35,7 +35,6 @@
 
 #include <linux/compiler.h>
 #include <linux/page-flags.h>
-#include <linux/mm.h>
 
 #include <asm/intrinsics.h>
 #include <asm/pgtable.h>
diff --git a/arch/ia64/kernel/process.c b/arch/ia64/kernel/process.c
index 968b5f33e725e..743aaf5283278 100644
--- a/arch/ia64/kernel/process.c
+++ b/arch/ia64/kernel/process.c
@@ -681,3 +681,4 @@ machine_power_off (void)
 	machine_halt();
 }
 
+EXPORT_SYMBOL(ia64_delay_loop);
diff --git a/arch/ia64/mm/ioremap.c b/arch/ia64/mm/ioremap.c
index a09cfa0645369..55fd3eb753ff9 100644
--- a/arch/ia64/mm/ioremap.c
+++ b/arch/ia64/mm/ioremap.c
@@ -8,6 +8,7 @@
 #include <linux/module.h>
 #include <linux/efi.h>
 #include <linux/io.h>
+#include <linux/mm.h>
 #include <linux/vmalloc.h>
 #include <asm/io.h>
 #include <asm/meminit.h>
-- 
2.26.0.rc2

[PATCH 5/5] microblaze: Remove mm.h from asm/uaccess.h

[Sebastian Andrzej Siewior]

[-- Attachment #1: Type: text/plain, Size: 1492 bytes --]

The defconfig compiles without linux/mm.h. With mm.h included the
include chain leands to:
|   CC      kernel/locking/percpu-rwsem.o
| In file included from include/linux/huge_mm.h:8,
|                  from include/linux/mm.h:567,
|                  from arch/microblaze/include/asm/uaccess.h:,
|                  from include/linux/uaccess.h:11,
|                  from include/linux/sched/task.h:11,
|                  from include/linux/sched/signal.h:9,
|                  from include/linux/rcuwait.h:6,
|                  from include/linux/percpu-rwsem.h:8,
|                  from kernel/locking/percpu-rwsem.c:6:
| include/linux/fs.h:1422:29: error: array type has incomplete element type 'struct percpu_rw_semaphore'
|  1422 |  struct percpu_rw_semaphore rw_sem[SB_FREEZE_LEVELS];

once rcuwait.h includes linux/sched/signal.h.

Remove the linux/mm.h include.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 arch/microblaze/include/asm/uaccess.h | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/microblaze/include/asm/uaccess.h b/arch/microblaze/include/asm/uaccess.h
index a1f206b90753a..4916d5fbea5e3 100644
--- a/arch/microblaze/include/asm/uaccess.h
+++ b/arch/microblaze/include/asm/uaccess.h
@@ -12,7 +12,6 @@
 #define _ASM_MICROBLAZE_UACCESS_H
 
 #include <linux/kernel.h>
-#include <linux/mm.h>
 
 #include <asm/mmu.h>
 #include <asm/page.h>
-- 
2.26.0.rc2

[PATCH 4/5 v2] ia64: Remove mm.h from asm/uaccess.h

[Sebastian Andrzej Siewior]

[-- Attachment #1: Type: text/plain, Size: 1944 bytes --]


The defconfig compiles without linux/mm.h. With mm.h included the
include chain leands to:
|   CC      kernel/locking/percpu-rwsem.o
| In file included from include/linux/huge_mm.h:8,
|                  from include/linux/mm.h:567,
|                  from arch/ia64/include/asm/uaccess.h:,
|                  from include/linux/uaccess.h:11,
|                  from include/linux/sched/task.h:11,
|                  from include/linux/sched/signal.h:9,
|                  from include/linux/rcuwait.h:6,
|                  from include/linux/percpu-rwsem.h:8,
|                  from kernel/locking/percpu-rwsem.c:6:
| include/linux/fs.h:1422:29: error: array type has incomplete element type 'struct percpu_rw_semaphore'
|  1422 |  struct percpu_rw_semaphore rw_sem[SB_FREEZE_LEVELS];

once rcuwait.h includes linux/sched/signal.h.

Remove the linux/mm.h include.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---

v1…v2: remove the EXPORT_SYMBOL hunk, was required to allmodconfig,
       unrelated to the series.

 arch/ia64/include/asm/uaccess.h | 1 -
 arch/ia64/mm/ioremap.c          | 1 +
 2 files changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/ia64/include/asm/uaccess.h b/arch/ia64/include/asm/uaccess.h
index 89782ad3fb887..5c7e79eccaeed 100644
--- a/arch/ia64/include/asm/uaccess.h
+++ b/arch/ia64/include/asm/uaccess.h
@@ -35,7 +35,6 @@
 
 #include <linux/compiler.h>
 #include <linux/page-flags.h>
-#include <linux/mm.h>
 
 #include <asm/intrinsics.h>
 #include <asm/pgtable.h>
diff --git a/arch/ia64/mm/ioremap.c b/arch/ia64/mm/ioremap.c
index a09cfa0645369..55fd3eb753ff9 100644
--- a/arch/ia64/mm/ioremap.c
+++ b/arch/ia64/mm/ioremap.c
@@ -8,6 +8,7 @@
 #include <linux/module.h>
 #include <linux/efi.h>
 #include <linux/io.h>
+#include <linux/mm.h>
 #include <linux/vmalloc.h>
 #include <asm/io.h>
 #include <asm/meminit.h>
-- 
2.26.0.rc2

[PATCH 4/5] ia64: Remove mm.h from asm/uaccess.h

[Sebastian Andrzej Siewior]

The defconfig compiles without linux/mm.h. With mm.h included the
include chain leands to:
|   CC      kernel/locking/percpu-rwsem.o
| In file included from include/linux/huge_mm.h:8,
|                  from include/linux/mm.h:567,
|                  from arch/ia64/include/asm/uaccess.h:,
|                  from include/linux/uaccess.h:11,
|                  from include/linux/sched/task.h:11,
|                  from include/linux/sched/signal.h:9,
|                  from include/linux/rcuwait.h:6,
|                  from include/linux/percpu-rwsem.h:8,
|                  from kernel/locking/percpu-rwsem.c:6:
| include/linux/fs.h:1422:29: error: array type has incomplete element type 'struct percpu_rw_semaphore'
|  1422 |  struct percpu_rw_semaphore rw_sem[SB_FREEZE_LEVELS];

once rcuwait.h includes linux/sched/signal.h.

Remove the linux/mm.h include.

Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: linux-ia64@vger.kernel.org
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 arch/ia64/include/asm/uaccess.h | 1 -
 arch/ia64/kernel/process.c      | 1 +
 arch/ia64/mm/ioremap.c          | 1 +
 3 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/ia64/include/asm/uaccess.h b/arch/ia64/include/asm/uaccess.h
index 89782ad3fb887..5c7e79eccaeed 100644
--- a/arch/ia64/include/asm/uaccess.h
+++ b/arch/ia64/include/asm/uaccess.h
@@ -35,7 +35,6 @@
 
 #include <linux/compiler.h>
 #include <linux/page-flags.h>
-#include <linux/mm.h>
 
 #include <asm/intrinsics.h>
 #include <asm/pgtable.h>
diff --git a/arch/ia64/kernel/process.c b/arch/ia64/kernel/process.c
index 968b5f33e725e..743aaf5283278 100644
--- a/arch/ia64/kernel/process.c
+++ b/arch/ia64/kernel/process.c
@@ -681,3 +681,4 @@ machine_power_off (void)
 	machine_halt();
 }
 
+EXPORT_SYMBOL(ia64_delay_loop);
diff --git a/arch/ia64/mm/ioremap.c b/arch/ia64/mm/ioremap.c
index a09cfa0645369..55fd3eb753ff9 100644
--- a/arch/ia64/mm/ioremap.c
+++ b/arch/ia64/mm/ioremap.c
@@ -8,6 +8,7 @@
 #include <linux/module.h>
 #include <linux/efi.h>
 #include <linux/io.h>
+#include <linux/mm.h>
 #include <linux/vmalloc.h>
 #include <asm/io.h>
 #include <asm/meminit.h>
-- 
2.26.0.rc2

[PATCH 4/5] ia64: Remove mm.h from asm/uaccess.h

[Sebastian Andrzej Siewior]

The defconfig compiles without linux/mm.h. With mm.h included the
include chain leands to:
|   CC      kernel/locking/percpu-rwsem.o
| In file included from include/linux/huge_mm.h:8,
|                  from include/linux/mm.h:567,
|                  from arch/ia64/include/asm/uaccess.h:,
|                  from include/linux/uaccess.h:11,
|                  from include/linux/sched/task.h:11,
|                  from include/linux/sched/signal.h:9,
|                  from include/linux/rcuwait.h:6,
|                  from include/linux/percpu-rwsem.h:8,
|                  from kernel/locking/percpu-rwsem.c:6:
| include/linux/fs.h:1422:29: error: array type has incomplete element type 'struct percpu_rw_semaphore'
|  1422 |  struct percpu_rw_semaphore rw_sem[SB_FREEZE_LEVELS];

once rcuwait.h includes linux/sched/signal.h.

Remove the linux/mm.h include.

Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: linux-ia64@vger.kernel.org
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 arch/ia64/include/asm/uaccess.h | 1 -
 arch/ia64/kernel/process.c      | 1 +
 arch/ia64/mm/ioremap.c          | 1 +
 3 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/ia64/include/asm/uaccess.h b/arch/ia64/include/asm/uaccess.h
index 89782ad3fb887..5c7e79eccaeed 100644
--- a/arch/ia64/include/asm/uaccess.h
+++ b/arch/ia64/include/asm/uaccess.h
@@ -35,7 +35,6 @@
 
 #include <linux/compiler.h>
 #include <linux/page-flags.h>
-#include <linux/mm.h>
 
 #include <asm/intrinsics.h>
 #include <asm/pgtable.h>
diff --git a/arch/ia64/kernel/process.c b/arch/ia64/kernel/process.c
index 968b5f33e725e..743aaf5283278 100644
--- a/arch/ia64/kernel/process.c
+++ b/arch/ia64/kernel/process.c
@@ -681,3 +681,4 @@ machine_power_off (void)
 	machine_halt();
 }
 
+EXPORT_SYMBOL(ia64_delay_loop);
diff --git a/arch/ia64/mm/ioremap.c b/arch/ia64/mm/ioremap.c
index a09cfa0645369..55fd3eb753ff9 100644
--- a/arch/ia64/mm/ioremap.c
+++ b/arch/ia64/mm/ioremap.c
@@ -8,6 +8,7 @@
 #include <linux/module.h>
 #include <linux/efi.h>
 #include <linux/io.h>
+#include <linux/mm.h>
 #include <linux/vmalloc.h>
 #include <asm/io.h>
 #include <asm/meminit.h>
-- 
2.26.0.rc2

[PATCH 4/5] ia64: Remove mm.h from asm/uaccess.h

[Sebastian Andrzej Siewior]

The defconfig compiles without linux/mm.h. With mm.h included the
include chain leands to:
|   CC      kernel/locking/percpu-rwsem.o
| In file included from include/linux/huge_mm.h:8,
|                  from include/linux/mm.h:567,
|                  from arch/ia64/include/asm/uaccess.h:,
|                  from include/linux/uaccess.h:11,
|                  from include/linux/sched/task.h:11,
|                  from include/linux/sched/signal.h:9,
|                  from include/linux/rcuwait.h:6,
|                  from include/linux/percpu-rwsem.h:8,
|                  from kernel/locking/percpu-rwsem.c:6:
| include/linux/fs.h:1422:29: error: array type has incomplete element type 'struct percpu_rw_semaphore'
|  1422 |  struct percpu_rw_semaphore rw_sem[SB_FREEZE_LEVELS];

once rcuwait.h includes linux/sched/signal.h.

Remove the linux/mm.h include.

Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: linux-ia64@vger.kernel.org
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 arch/ia64/include/asm/uaccess.h | 1 -
 arch/ia64/kernel/process.c      | 1 +
 arch/ia64/mm/ioremap.c          | 1 +
 3 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/ia64/include/asm/uaccess.h b/arch/ia64/include/asm/uaccess.h
index 89782ad3fb887..5c7e79eccaeed 100644
--- a/arch/ia64/include/asm/uaccess.h
+++ b/arch/ia64/include/asm/uaccess.h
@@ -35,7 +35,6 @@
 
 #include <linux/compiler.h>
 #include <linux/page-flags.h>
-#include <linux/mm.h>
 
 #include <asm/intrinsics.h>
 #include <asm/pgtable.h>
diff --git a/arch/ia64/kernel/process.c b/arch/ia64/kernel/process.c
index 968b5f33e725e..743aaf5283278 100644
--- a/arch/ia64/kernel/process.c
+++ b/arch/ia64/kernel/process.c
@@ -681,3 +681,4 @@ machine_power_off (void)
 	machine_halt();
 }
 
+EXPORT_SYMBOL(ia64_delay_loop);
diff --git a/arch/ia64/mm/ioremap.c b/arch/ia64/mm/ioremap.c
index a09cfa0645369..55fd3eb753ff9 100644
--- a/arch/ia64/mm/ioremap.c
+++ b/arch/ia64/mm/ioremap.c
@@ -8,6 +8,7 @@
 #include <linux/module.h>
 #include <linux/efi.h>
 #include <linux/io.h>
+#include <linux/mm.h>
 #include <linux/vmalloc.h>
 #include <asm/io.h>
 #include <asm/meminit.h>
-- 
2.26.0.rc2