Re: [PATCH] selftests/bpf: Fix bpf selftest build error
From: Venkat Rao Bagalkote <hidden>
Date: 2025-05-12 03:54:51
Also in:
bpf, linux-kselftest, linux-next, lkml
On 09/05/25 5:53 pm, Saket Kumar Bhaskar wrote:
quoted hunk ↗ jump to hunk
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 <redacted> Closes: https://lore.kernel.org/all/e915da49-2b9a-4c4c-a34f-877f378129f6@linux.ibm.com/ (local) Signed-off-by: Saket Kumar Bhaskar <redacted> --- 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) { struct bpf_testmod_test_read_ctx ctx = {@@ -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) { struct bpf_testmod_test_write_ctx ctx = {
Tested this patch by applying on top of next-20250508 and if fixes the
build issue. Hence,
Tested-by: Venkat Rao Bagalkote <redacted>
commit f48887a98b78880b7711aca311fbbbcaad6c4e3b (tag: next-20250508,
origin/master, origin/HEAD, bpf_arena)
Author: Stephen Rothwell [off-list ref]
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.