Justin,
On Tue, Aug 22, 2023 at 10:44 PM Nick Desaulniers ndesaulniers@google.com wrote:
- Ben, author of commit dbb60c8a26da ("selftests: add tests for the
HID-bpf initial implementation")
On Tue, Aug 22, 2023 at 1:34 PM Justin Stitt justinstitt@google.com wrote:
Hi, I'd like to get some help with building the kselftest target.
I am running into some warnings within the hid tree: | progs/hid_bpf_helpers.h:9:38: error: declaration of 'struct hid_bpf_ctx' will \ | not be visible outside of this function [-Werror,-Wvisibility] | 9 | extern __u8 *hid_bpf_get_data(struct hid_bpf_ctx *ctx, | | ^ | progs/hid.c:23:35: error: incompatible pointer types passing 'struct hid_bpf_ctx *' \ | to parameter of type 'struct hid_bpf_ctx *' [-Werror,-Wincompatible-pointer-types] | 23 | __u8 *rw_data = hid_bpf_get_data(hid_ctx, 0 /* offset */, 3 /* size */);
This warning, amongst others, is due to some symbol not being included. In this case, `struct hid_bpf_ctx` is not being defined anywhere that I can see inside of the testing tree itself.
Instead, `struct hid_bpf_ctx` is defined and implemented at `include/linux/hid_bpf.h`. AFAIK, I cannot just include this header as the tools directory is a separate entity from kbuild and these tests are meant to be built/ran without relying on kernel headers. Am I correct in this assumption? At any rate, the include itself doesn't work. How can I properly include this struct definition and fix the warning(s)?
Please note that we cannot just forward declare the struct as it is being dereferenced and would then yield a completely different error/warning for an incomplete type. We need the entire implementation for the struct included.
Other symbols also defined in `include/linux/hid_bpf.h` that we need are `struct hid_report_type` and `HID_BPF_FLAG...`
Here's the invocation I am running to build kselftest: `$ make LLVM=1 ARCH=x86_64 mrproper headers && make LLVM=1 ARCH=x86_64 -j128 V=1 -C tools/testing/selftests`
I think I fixed the same issue in the script I am running to launch those tests in a VM. This was in commit f9abdcc617dad5f14bbc2ebe96ee99f3e6de0c4e (in the v6.5-rc+ series).
And in the commit log, I wrote: ``` According to commit 01d6c48a828b ("Documentation: kselftest: "make headers" is a prerequisite"), running the kselftests requires to run "make headers" first. ```
So my assumption is that you also need to run "make headers" with the proper flags before compiling the selftests themselves (I might be wrong but that's how I read the commit).
Cheers, Benjamin
If anyone is currently getting clean builds of kselftest with clang, what invocation works for you?
Link: https://github.com/ClangBuiltLinux/linux/issues/1698 Full-build-log: https://gist.github.com/JustinStitt/b217f6e47c1d762e5e1cc6c3532f1bbb (V=1)
Thanks. Justin
-- Thanks, ~Nick Desaulniers