Re: [vfs:work.aio 10/12] fs/aio.c:1444: undefined reference to `ioprio_check_cap'

[Al Viro <viro@xxxxxxxxxxxxxxxxxx>]

On Fri, Jun 01, 2018 at 08:36:47AM +0800, kbuild test robot wrote:
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs.git work.aio
> head:   087e566916ce2cde4f20a148607c9c3591f46f67
> commit: d9a08a9e616beeccdbd0e7262b7225ffdfa49e92 [10/12] fs: Add aio iopriority support
> config: x86_64-randconfig-u0-06010558 (attached as .config)
> compiler: gcc-5 (Debian 5.5.0-3) 5.4.1 20171010
> reproduce:
>         git checkout d9a08a9e616beeccdbd0e7262b7225ffdfa49e92
>         # save the attached .config to linux build tree
>         make ARCH=x86_64 
> 
> All errors (new ones prefixed by >>):
> 
>    fs/aio.o: In function `aio_prep_rw':
> >> fs/aio.c:1444: undefined reference to `ioprio_check_cap'

Huh?  In the same commit:
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -36,6 +36,7 @@
 #include <linux/delayed_call.h>
 #include <linux/uuid.h>
 #include <linux/errseq.h>
+#include <linux/ioprio.h>

Two commits earlier:
--- a/include/linux/ioprio.h
+++ b/include/linux/ioprio.h
@@ -77,4 +77,6 @@ extern int ioprio_best(unsigned short aprio, unsigned short bprio);
 
 extern int set_task_ioprio(struct task_struct *task, int ioprio);
 
+extern int ioprio_check_cap(int ioprio);
+

and fs/aio.c definitely contains include of linux/fs.h...