On Sat, 20 Feb 2021, Randy Dunlap wrote:
> When CONFIG_EPOLL is not set/enabled, sys_oabi-compat.c has build
> errors. Fix these by surrounding them with ifdef CONFIG_EPOLL/endif
> and providing stubs for the "EPOLL is not set" case.
>
> ../arch/arm/kernel/sys_oabi-compat.c: In function 'sys_oabi_epoll_ctl':
> ../arch/arm/kernel/sys_oabi-compat.c:257:6: error: implicit declaration of
> function 'ep_op_has_event' [-Werror=implicit-function-declaration]
> 257 | if (ep_op_has_event(op) &&
> | ^~~~~~~~~~~~~~~
> ../arch/arm/kernel/sys_oabi-compat.c:264:9: error: implicit declaration of
> function 'do_epoll_ctl'; did you mean 'sys_epoll_ctl'?
> [-Werror=implicit-function-declaration]
> 264 | return do_epoll_ctl(epfd, op, fd, &kernel, false);
> | ^~~~~~~~~~~~
>
> Fixes: c281634c8652 ("ARM: compat: remove KERNEL_DS usage in
> sys_oabi_epoll_ctl()")
> Signed-off-by: Randy Dunlap <[email protected]>
> Reported-by: kernel test robot <[email protected]> # from an lkp .config file
> Cc: Russell King <[email protected]>
> Cc: [email protected]
> Cc: Nicolas Pitre <[email protected]>
> Cc: Alexander Viro <[email protected]>
> Cc: [email protected]
Acked-by: Nicolas Pitre <[email protected]>
> ---
> v2: use correct Fixes: tag (thanks, rmk)
> v3: add patches@ to Cc: list
>
> arch/arm/kernel/sys_oabi-compat.c | 15 +++++++++++++++
> 1 file changed, 15 insertions(+)
>
> --- linux-next-20201214.orig/arch/arm/kernel/sys_oabi-compat.c
> +++ linux-next-20201214/arch/arm/kernel/sys_oabi-compat.c
> @@ -248,6 +248,7 @@ struct oabi_epoll_event {
> __u64 data;
> } __attribute__ ((packed,aligned(4)));
>
> +#ifdef CONFIG_EPOLL
> asmlinkage long sys_oabi_epoll_ctl(int epfd, int op, int fd,
> struct oabi_epoll_event __user *event)
> {
> @@ -298,6 +299,20 @@ asmlinkage long sys_oabi_epoll_wait(int
> kfree(kbuf);
> return err ? -EFAULT : ret;
> }
> +#else
> +asmlinkage long sys_oabi_epoll_ctl(int epfd, int op, int fd,
> + struct oabi_epoll_event __user *event)
> +{
> + return -EINVAL;
> +}
> +
> +asmlinkage long sys_oabi_epoll_wait(int epfd,
> + struct oabi_epoll_event __user *events,
> + int maxevents, int timeout)
> +{
> + return -EINVAL;
> +}
> +#endif
>
> struct oabi_sembuf {
> unsigned short sem_num;
>
