PowerPC-64 follows the LP64 data model and then uses int-l64.h (instead of int-ll64.h like most architectures) for user space code. Here is the same code with the (suggested) "%lu" token on x86_86: samples/landlock/sandboxer.c: In function ‘populate_ruleset_net’: samples/landlock/sandboxer.c:170:77: error: format ‘%lu’ expects argument of type ‘long unsigned int’, but argument 3 has type ‘__u64’ {aka ‘long long unsigned int’} [-Werror=format=] 170 | "Failed to update the ruleset with port \"%lu\": %s\n", | ~~^ | | | long unsigned int | %llu 171 | net_port.port, strerror(errno)); | ~~~~~~~~~~~~~ | | | __u64 {aka long long unsigned int} We would then need to cast __u64 to unsigned long long to avoid this warning, which may look useless, of even buggy, for people taking a look at this sample. Anyway, it makes more sense to cast it to __u16 because it is the expected type for a TCP port. I'm updating the patch with that. Konstantin, please take this fix for the next series: https://git.kernel.org/mic/c/fc9de206a61a On Tue, Oct 03, 2023 at 02:27:37PM +1100, Stephen Rothwell wrote: > Hi all, > > After merging the landlock tree, today's linux-next build (powerpc > allyesconfig) produced this warning: > > samples/landlock/sandboxer.c: In function 'populate_ruleset_net': > samples/landlock/sandboxer.c:170:78: warning: format '%llu' expects argument of type 'long long unsigned int', but argument 3 has type '__u64' {aka 'long unsigned int'} [-Wformat=] > 170 | "Failed to update the ruleset with port \"%llu\": %s\n", > | ~~~^ > | | > | long long unsigned int > | %lu > 171 | net_port.port, strerror(errno)); > | ~~~~~~~~~~~~~ > | | > | __u64 {aka long unsigned int} > > Introduced by commit > > 24889e7a2079 ("samples/landlock: Add network demo") > > -- > Cheers, > Stephen Rothwell