[mark:arm64/ftrace/minimal-regs 5/6] include/linux/ftrace.h:422:57: warning: 'struct ftrace_regs' declared inside parameter list will not be visible outside of this definition or declaration

From: kernel test robot
Date: Wed Jun 01 2022 - 11:30:15 EST


tree: https://git.kernel.org/pub/scm/linux/kernel/git/mark/linux.git arm64/ftrace/minimal-regs
head: b0741d059a9f19a1aa1191833140f53e41f1775a
commit: c694698df7f633bcbdf8bc0edb94f4a70ed0d092 [5/6] ftrace: pass fregs to arch_ftrace_set_direct_caller()
config: um-i386_defconfig (https://download.01.org/0day-ci/archive/20220601/202206012357.BH7ZUhqM-lkp@xxxxxxxxx/config)
compiler: gcc-11 (Debian 11.3.0-1) 11.3.0
reproduce (this is a W=1 build):
# https://git.kernel.org/pub/scm/linux/kernel/git/mark/linux.git/commit/?id=c694698df7f633bcbdf8bc0edb94f4a70ed0d092
git remote add mark https://git.kernel.org/pub/scm/linux/kernel/git/mark/linux.git
git fetch --no-tags mark arm64/ftrace/minimal-regs
git checkout c694698df7f633bcbdf8bc0edb94f4a70ed0d092
# save the config file
mkdir build_dir && cp config build_dir/.config
make W=1 O=build_dir ARCH=um SUBARCH=i386 SHELL=/bin/bash fs/

If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@xxxxxxxxx>

All warnings (new ones prefixed by >>):

In file included from include/linux/perf_event.h:51,
from include/linux/trace_events.h:10,
from include/trace/syscall.h:7,
from include/linux/syscalls.h:88,
from fs/binfmt_misc.c:27:
>> include/linux/ftrace.h:422:57: warning: 'struct ftrace_regs' declared inside parameter list will not be visible outside of this definition or declaration
422 | static inline void arch_ftrace_set_direct_caller(struct ftrace_regs *fregs,
| ^~~~~~~~~~~
--
In file included from include/linux/perf_event.h:51,
from include/linux/trace_events.h:10,
from include/trace/syscall.h:7,
from include/linux/syscalls.h:88,
from fs/pipe.c:24:
>> include/linux/ftrace.h:422:57: warning: 'struct ftrace_regs' declared inside parameter list will not be visible outside of this definition or declaration
422 | static inline void arch_ftrace_set_direct_caller(struct ftrace_regs *fregs,
| ^~~~~~~~~~~
fs/pipe.c:757:15: warning: no previous prototype for 'account_pipe_buffers' [-Wmissing-prototypes]
757 | unsigned long account_pipe_buffers(struct user_struct *user,
| ^~~~~~~~~~~~~~~~~~~~
fs/pipe.c:763:6: warning: no previous prototype for 'too_many_pipe_buffers_soft' [-Wmissing-prototypes]
763 | bool too_many_pipe_buffers_soft(unsigned long user_bufs)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
fs/pipe.c:770:6: warning: no previous prototype for 'too_many_pipe_buffers_hard' [-Wmissing-prototypes]
770 | bool too_many_pipe_buffers_hard(unsigned long user_bufs)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
fs/pipe.c:777:6: warning: no previous prototype for 'pipe_is_unprivileged_user' [-Wmissing-prototypes]
777 | bool pipe_is_unprivileged_user(void)
| ^~~~~~~~~~~~~~~~~~~~~~~~~
fs/pipe.c:1253:5: warning: no previous prototype for 'pipe_resize_ring' [-Wmissing-prototypes]
1253 | int pipe_resize_ring(struct pipe_inode_info *pipe, unsigned int nr_slots)
| ^~~~~~~~~~~~~~~~
--
In file included from include/linux/perf_event.h:51,
from include/linux/trace_events.h:10,
from include/trace/syscall.h:7,
from include/linux/syscalls.h:88,
from fs/d_path.c:2:
>> include/linux/ftrace.h:422:57: warning: 'struct ftrace_regs' declared inside parameter list will not be visible outside of this definition or declaration
422 | static inline void arch_ftrace_set_direct_caller(struct ftrace_regs *fregs,
| ^~~~~~~~~~~
fs/d_path.c:318:7: warning: no previous prototype for 'simple_dname' [-Wmissing-prototypes]
318 | char *simple_dname(struct dentry *dentry, char *buffer, int buflen)
| ^~~~~~~~~~~~
--
In file included from include/linux/perf_event.h:51,
from include/linux/trace_events.h:10,
from include/trace/syscall.h:7,
from include/linux/syscalls.h:88,
from fs/io_uring.c:45:
>> include/linux/ftrace.h:422:57: warning: 'struct ftrace_regs' declared inside parameter list will not be visible outside of this definition or declaration
422 | static inline void arch_ftrace_set_direct_caller(struct ftrace_regs *fregs,
| ^~~~~~~~~~~
fs/io_uring.c: In function '__io_submit_flush_completions':
fs/io_uring.c:3152:40: warning: variable 'prev' set but not used [-Wunused-but-set-variable]
3152 | struct io_wq_work_node *node, *prev;
| ^~~~


vim +422 include/linux/ftrace.h

407
408 #ifndef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
409 /*
410 * This must be implemented by the architecture.
411 * It is the way the ftrace direct_ops helper, when called
412 * via ftrace (because there's other callbacks besides the
413 * direct call), can inform the architecture's trampoline that this
414 * routine has a direct caller, and what the caller is.
415 *
416 * For example, in x86, it returns the direct caller
417 * callback function via the regs->orig_ax parameter.
418 * Then in the ftrace trampoline, if this is set, it makes
419 * the return from the trampoline jump to the direct caller
420 * instead of going back to the function it just traced.
421 */
> 422 static inline void arch_ftrace_set_direct_caller(struct ftrace_regs *fregs,
423 unsigned long addr) { }
424 #endif /* CONFIG_HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */
425

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