On 09/05/25 5:53 pm, Saket Kumar Bhaskar wrote:
On linux-next, build for bpf selftest displays an error due to mismatch in the expected function signature of bpf_testmod_test_read and bpf_testmod_test_write.
Commit 97d06802d10a ("sysfs: constify bin_attribute argument of bin_attribute::read/write()") changed the required type for struct bin_attribute to const struct bin_attribute.
To resolve the error, update corresponding signature for the callback.
Reported-by: Venkat Rao Bagalkote venkat88@linux.ibm.com Closes: https://lore.kernel.org/all/e915da49-2b9a-4c4c-a34f-877f378129f6@linux.ibm.c... Signed-off-by: Saket Kumar Bhaskar skb99@linux.ibm.com
tools/testing/selftests/bpf/test_kmods/bpf_testmod.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/tools/testing/selftests/bpf/test_kmods/bpf_testmod.c b/tools/testing/selftests/bpf/test_kmods/bpf_testmod.c index 2e54b95ad898..194c442580ee 100644 --- a/tools/testing/selftests/bpf/test_kmods/bpf_testmod.c +++ b/tools/testing/selftests/bpf/test_kmods/bpf_testmod.c @@ -385,7 +385,7 @@ int bpf_testmod_fentry_ok; noinline ssize_t bpf_testmod_test_read(struct file *file, struct kobject *kobj,
struct bin_attribute *bin_attr,
const struct bin_attribute *bin_attr, char *buf, loff_t off, size_t len)@@ -465,7 +465,7 @@ ALLOW_ERROR_INJECTION(bpf_testmod_test_read, ERRNO); noinline ssize_t bpf_testmod_test_write(struct file *file, struct kobject *kobj,
struct bin_attribute *bin_attr,
const struct bin_attribute *bin_attr, char *buf, loff_t off, size_t len)
Tested this patch by applying on top of next-20250508 and if fixes the build issue. Hence,
Tested-by: Venkat Rao Bagalkote venkat88@linux.ibm.com
commit f48887a98b78880b7711aca311fbbbcaad6c4e3b (tag: next-20250508, origin/master, origin/HEAD, bpf_arena) Author: Stephen Rothwell sfr@canb.auug.org.au Date: Thu May 8 18:45:50 2025 +1000
Add linux-next specific files for 20250508
After this patch:
TEST-OBJ [test_progs-cpuv4] xdp_flowtable.test.o TEST-OBJ [test_progs-cpuv4] xdp_info.test.o TEST-OBJ [test_progs-cpuv4] xdp_link.test.o TEST-OBJ [test_progs-cpuv4] xdp_metadata.test.o TEST-OBJ [test_progs-cpuv4] xdp_noinline.test.o TEST-OBJ [test_progs-cpuv4] xdp_perf.test.o TEST-OBJ [test_progs-cpuv4] xdp_synproxy.test.o TEST-OBJ [test_progs-cpuv4] xdp_vlan.test.o TEST-OBJ [test_progs-cpuv4] xdpwall.test.o TEST-OBJ [test_progs-cpuv4] xfrm_info.test.o BINARY bench BINARY test_maps BINARY test_progs BINARY test_progs-no_alu32 BINARY test_progs-cpuv4
Before this patch:
CLANG /root/linux-next/tools/testing/selftests/bpf/tools/build/bpftool/profiler.bpf.o bpf_testmod.c:494:17: error: initialization of ‘ssize_t (*)(struct file *, struct kobject *, const struct bin_attribute *, char *, loff_t, size_t)’ {aka ‘long int (*)(struct file *, struct kobject *, const struct bin_attribute *, char *, long long int, long unsigned int)’} from incompatible pointer type ‘ssize_t (*)(struct file *, struct kobject *, struct bin_attribute *, char *, loff_t, size_t)’ {aka ‘long int (*)(struct file *, struct kobject *, struct bin_attribute *, char *, long long int, long unsigned int)’} [-Wincompatible-pointer-types] 494 | .read = bpf_testmod_test_read, | ^~~~~~~~~~~~~~~~~~~~~ bpf_testmod.c:494:17: note: (near initialization for ‘bin_attr_bpf_testmod_file.read’) bpf_testmod.c:495:18: error: initialization of ‘ssize_t (*)(struct file *, struct kobject *, const struct bin_attribute *, char *, loff_t, size_t)’ {aka ‘long int (*)(struct file *, struct kobject *, const struct bin_attribute *, char *, long long int, long unsigned int)’} from incompatible pointer type ‘ssize_t (*)(struct file *, struct kobject *, struct bin_attribute *, char *, loff_t, size_t)’ {aka ‘long int (*)(struct file *, struct kobject *, struct bin_attribute *, char *, long long int, long unsigned int)’} [-Wincompatible-pointer-types] 495 | .write = bpf_testmod_test_write, | ^~~~~~~~~~~~~~~~~~~~~~ bpf_testmod.c:495:18: note: (near initialization for ‘bin_attr_bpf_testmod_file.write’) make[4]: *** [/root/linux-next/scripts/Makefile.build:203: bpf_testmod.o] Error 1 make[3]: *** [/root/linux-next/Makefile:2009: .] Error 2 make[2]: *** [Makefile:248: __sub-make] Error 2 make[1]: *** [Makefile:18: all] Error 2 make: *** [Makefile:282: test_kmods/bpf_testmod.ko] Error 2
Regards,
Venkat.