diff mbox series

[SRU,Bionic,1/1] include/uapi/linux/swab.h: fix userspace breakage, use __BITS_PER_LONG for swap

Message ID 20200507094122.28921-2-kleber.souza@canonical.com
State New
Headers show
Series Fix breaking userpace build on bionic proposed | expand

Commit Message

Kleber Sacilotto de Souza May 7, 2020, 9:41 a.m. UTC
From: Christian Borntraeger <borntraeger@de.ibm.com>

BugLink: https://bugs.launchpad.net/bugs/1877123

QEMU has a funny new build error message when I use the upstream kernel
headers:

      CC      block/file-posix.o
    In file included from /home/cborntra/REPOS/qemu/include/qemu/timer.h:4,
                     from /home/cborntra/REPOS/qemu/include/qemu/timed-average.h:29,
                     from /home/cborntra/REPOS/qemu/include/block/accounting.h:28,
                     from /home/cborntra/REPOS/qemu/include/block/block_int.h:27,
                     from /home/cborntra/REPOS/qemu/block/file-posix.c:30:
    /usr/include/linux/swab.h: In function `__swab':
    /home/cborntra/REPOS/qemu/include/qemu/bitops.h:20:34: error: "sizeof" is not defined, evaluates to 0 [-Werror=undef]
       20 | #define BITS_PER_LONG           (sizeof (unsigned long) * BITS_PER_BYTE)
          |                                  ^~~~~~
    /home/cborntra/REPOS/qemu/include/qemu/bitops.h:20:41: error: missing binary operator before token "("
       20 | #define BITS_PER_LONG           (sizeof (unsigned long) * BITS_PER_BYTE)
          |                                         ^
    cc1: all warnings being treated as errors
    make: *** [/home/cborntra/REPOS/qemu/rules.mak:69: block/file-posix.o] Error 1
    rm tests/qemu-iotests/socket_scm_helper.o

This was triggered by commit d5767057c9a ("uapi: rename ext2_swab() to
swab() and share globally in swab.h").  That patch is doing

  #include <asm/bitsperlong.h>

but it uses BITS_PER_LONG.

The kernel file asm/bitsperlong.h provide only __BITS_PER_LONG.

Let us use the __ variant in swap.h

Link: http://lkml.kernel.org/r/20200213142147.17604-1-borntraeger@de.ibm.com
Fixes: d5767057c9a ("uapi: rename ext2_swab() to swab() and share globally in swab.h")
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Yury Norov <yury.norov@gmail.com>
Cc: Allison Randal <allison@lohutok.net>
Cc: Joe Perches <joe@perches.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Cc: Torsten Hilbrich <torsten.hilbrich@secunet.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit 467d12f5c7842896d2de3ced74e4147ee29e97c8)
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
---
 include/uapi/linux/swab.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Stefan Bader May 7, 2020, 9:44 a.m. UTC | #1
On 07.05.20 11:41, Kleber Sacilotto de Souza wrote:
> From: Christian Borntraeger <borntraeger@de.ibm.com>
> 
> BugLink: https://bugs.launchpad.net/bugs/1877123
> 
> QEMU has a funny new build error message when I use the upstream kernel
> headers:
> 
>       CC      block/file-posix.o
>     In file included from /home/cborntra/REPOS/qemu/include/qemu/timer.h:4,
>                      from /home/cborntra/REPOS/qemu/include/qemu/timed-average.h:29,
>                      from /home/cborntra/REPOS/qemu/include/block/accounting.h:28,
>                      from /home/cborntra/REPOS/qemu/include/block/block_int.h:27,
>                      from /home/cborntra/REPOS/qemu/block/file-posix.c:30:
>     /usr/include/linux/swab.h: In function `__swab':
>     /home/cborntra/REPOS/qemu/include/qemu/bitops.h:20:34: error: "sizeof" is not defined, evaluates to 0 [-Werror=undef]
>        20 | #define BITS_PER_LONG           (sizeof (unsigned long) * BITS_PER_BYTE)
>           |                                  ^~~~~~
>     /home/cborntra/REPOS/qemu/include/qemu/bitops.h:20:41: error: missing binary operator before token "("
>        20 | #define BITS_PER_LONG           (sizeof (unsigned long) * BITS_PER_BYTE)
>           |                                         ^
>     cc1: all warnings being treated as errors
>     make: *** [/home/cborntra/REPOS/qemu/rules.mak:69: block/file-posix.o] Error 1
>     rm tests/qemu-iotests/socket_scm_helper.o
> 
> This was triggered by commit d5767057c9a ("uapi: rename ext2_swab() to
> swab() and share globally in swab.h").  That patch is doing
> 
>   #include <asm/bitsperlong.h>
> 
> but it uses BITS_PER_LONG.
> 
> The kernel file asm/bitsperlong.h provide only __BITS_PER_LONG.
> 
> Let us use the __ variant in swap.h
> 
> Link: http://lkml.kernel.org/r/20200213142147.17604-1-borntraeger@de.ibm.com
> Fixes: d5767057c9a ("uapi: rename ext2_swab() to swab() and share globally in swab.h")
> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
> Cc: Yury Norov <yury.norov@gmail.com>
> Cc: Allison Randal <allison@lohutok.net>
> Cc: Joe Perches <joe@perches.com>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
> Cc: Torsten Hilbrich <torsten.hilbrich@secunet.com>
> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
> (cherry picked from commit 467d12f5c7842896d2de3ced74e4147ee29e97c8)
> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
> ---
>  include/uapi/linux/swab.h | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/include/uapi/linux/swab.h b/include/uapi/linux/swab.h
> index fa7f97da5b76..7272f85d6d6a 100644
> --- a/include/uapi/linux/swab.h
> +++ b/include/uapi/linux/swab.h
> @@ -135,9 +135,9 @@ static inline __attribute_const__ __u32 __fswahb32(__u32 val)
>  
>  static __always_inline unsigned long __swab(const unsigned long y)
>  {
> -#if BITS_PER_LONG == 64
> +#if __BITS_PER_LONG == 64
>  	return __swab64(y);
> -#else /* BITS_PER_LONG == 32 */
> +#else /* __BITS_PER_LONG == 32 */
>  	return __swab32(y);
>  #endif
>  }
>
Andrea Righi May 7, 2020, 9:48 a.m. UTC | #2
On Thu, May 07, 2020 at 11:41:22AM +0200, Kleber Sacilotto de Souza wrote:
> From: Christian Borntraeger <borntraeger@de.ibm.com>
> 
> BugLink: https://bugs.launchpad.net/bugs/1877123
> 
> QEMU has a funny new build error message when I use the upstream kernel
> headers:
> 
>       CC      block/file-posix.o
>     In file included from /home/cborntra/REPOS/qemu/include/qemu/timer.h:4,
>                      from /home/cborntra/REPOS/qemu/include/qemu/timed-average.h:29,
>                      from /home/cborntra/REPOS/qemu/include/block/accounting.h:28,
>                      from /home/cborntra/REPOS/qemu/include/block/block_int.h:27,
>                      from /home/cborntra/REPOS/qemu/block/file-posix.c:30:
>     /usr/include/linux/swab.h: In function `__swab':
>     /home/cborntra/REPOS/qemu/include/qemu/bitops.h:20:34: error: "sizeof" is not defined, evaluates to 0 [-Werror=undef]
>        20 | #define BITS_PER_LONG           (sizeof (unsigned long) * BITS_PER_BYTE)
>           |                                  ^~~~~~
>     /home/cborntra/REPOS/qemu/include/qemu/bitops.h:20:41: error: missing binary operator before token "("
>        20 | #define BITS_PER_LONG           (sizeof (unsigned long) * BITS_PER_BYTE)
>           |                                         ^
>     cc1: all warnings being treated as errors
>     make: *** [/home/cborntra/REPOS/qemu/rules.mak:69: block/file-posix.o] Error 1
>     rm tests/qemu-iotests/socket_scm_helper.o
> 
> This was triggered by commit d5767057c9a ("uapi: rename ext2_swab() to
> swab() and share globally in swab.h").  That patch is doing
> 
>   #include <asm/bitsperlong.h>
> 
> but it uses BITS_PER_LONG.
> 
> The kernel file asm/bitsperlong.h provide only __BITS_PER_LONG.
> 
> Let us use the __ variant in swap.h
> 
> Link: http://lkml.kernel.org/r/20200213142147.17604-1-borntraeger@de.ibm.com
> Fixes: d5767057c9a ("uapi: rename ext2_swab() to swab() and share globally in swab.h")
> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
> Cc: Yury Norov <yury.norov@gmail.com>
> Cc: Allison Randal <allison@lohutok.net>
> Cc: Joe Perches <joe@perches.com>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
> Cc: Torsten Hilbrich <torsten.hilbrich@secunet.com>
> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
> (cherry picked from commit 467d12f5c7842896d2de3ced74e4147ee29e97c8)
> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

Looks good to me. Thanks.

Acked-by: Andrea Righi <andrea.righi@canonical.com>
diff mbox series

Patch

diff --git a/include/uapi/linux/swab.h b/include/uapi/linux/swab.h
index fa7f97da5b76..7272f85d6d6a 100644
--- a/include/uapi/linux/swab.h
+++ b/include/uapi/linux/swab.h
@@ -135,9 +135,9 @@  static inline __attribute_const__ __u32 __fswahb32(__u32 val)
 
 static __always_inline unsigned long __swab(const unsigned long y)
 {
-#if BITS_PER_LONG == 64
+#if __BITS_PER_LONG == 64
 	return __swab64(y);
-#else /* BITS_PER_LONG == 32 */
+#else /* __BITS_PER_LONG == 32 */
 	return __swab32(y);
 #endif
 }