6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Arnd Bergmann <arnd@xxxxxxxx> [ Upstream commit 79038a99445f69c5d28494dd4f8c6f0509f65b2e ] In some randconfig builds, kernfs ends up being disabled, so there is no prototype for kernfs_generic_poll() In file included from kernel/sched/build_utility.c:97: kernel/sched/psi.c:1479:3: error: implicit declaration of function 'kernfs_generic_poll' is invalid in C99 [-Werror,-Wimplicit-function-declaration] kernfs_generic_poll(t->of, wait); ^ Add a stub helper for it, as we have it for other kernfs functions. Fixes: aff037078ecae ("sched/psi: use kernfs polling functions for PSI trigger polling") Fixes: 147e1a97c4a0b ("fs: kernfs: add poll file operation") Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> Reviewed-by: Chengming Zhou <zhouchengming@xxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20230724121823.1357562-1-arnd@xxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- include/linux/kernfs.h | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/include/linux/kernfs.h b/include/linux/kernfs.h index 73f5c120def88..2a36f3218b510 100644 --- a/include/linux/kernfs.h +++ b/include/linux/kernfs.h @@ -550,6 +550,10 @@ static inline int kernfs_setattr(struct kernfs_node *kn, const struct iattr *iattr) { return -ENOSYS; } +static inline __poll_t kernfs_generic_poll(struct kernfs_open_file *of, + struct poll_table_struct *pt) +{ return -ENOSYS; } + static inline void kernfs_notify(struct kernfs_node *kn) { } static inline int kernfs_xattr_get(struct kernfs_node *kn, const char *name, -- 2.40.1