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Khem Raj
e8b8f3ddd9
The build host HOME directory check recently added to OE-Core's buildpaths QA test flags the ptest gtest binary: WARNING: bpftrace-0.25.1-r0 do_package_qa: QA Issue: File /usr/lib/bpftrace/ptest/tests/bpftrace_test in package bpftrace-ptest contains a reference to the build host HOME directory. [buildpaths] WARNING: bpftrace-0.25.1-r0 do_package_qa: QA Issue: File /usr/lib/bpftrace/ptest/tests/.debug/bpftrace_test in package bpftrace-dbg contains a reference to the build host HOME directory. [buildpaths] cmake/BuildBPF.cmake links the intermediate DWARF carrier binary data_source_exe with the plain build host gcc, which bakes the host dynamic loader's absolute path into the PT_INTERP segment. With a distro gcc that is an innocuous /lib64/ld-linux-x86-64.so.2, but when the host toolchain is a buildtools-extended/SDK gcc installed under the build user's home directory (as on the autobuilder workers), it is a $HOME-prefixed path like /srv/pokybuild/.../buildtools/sysroots/x86_64-pokysdk-linux/lib/ld-linux-x86-64.so.2 The executable is then embedded byte-for-byte into bpftrace_test via embed()/xxd (tests/data/CMakeLists.txt), so the path ends up in the test binary's .rodata, triggering the bpftrace-ptest warning. And because cmake/Embed.tmpl declares the embedded blob as a constexpr array, gcc additionally copies its contents into .debug_info as DW_AT_const_value, which is how the same string survives objcopy --only-keep-debug into the split debug file, triggering the bpftrace-dbg warning. This is the same embedding mechanism that previously leaked TMPDIR paths, fixed for the compile step by the DEBUG_PREFIX_MAP patch; the link step was still leaking. The tests only write this binary to a temp file and use it as a uprobe target (tests/dwarf_common.h), parsing its DWARF and symbols; it is never executed. So link it with -nostdlib -no-pie -Wl,--entry=0: no interpreter, no host crt objects, no dynamic segment, and thus nothing host-specific in the embedded blob. Function symbols, DWARF type information and the pahole -J BTF encoding step are unaffected, and the field_analyser_dwarf ptests still pass. Because the object is now linked -nostdlib it must not reference the libc stack-protector runtime. Host gcc toolchains that default to -fstack-protector-strong (e.g. Debian/Ubuntu and the Yocto autobuilder workers) otherwise leave an undefined reference and the link fails: ld: data_source.o: in function `main': data_source.c:212: undefined reference to `__stack_chk_fail' collect2: error: ld returned 1 exit status Compile the object and link the binary with -fno-stack-protector; the canary is irrelevant to a DWARF/BTF carrier that is never run. Signed-off-by: Khem Raj <khem.raj@oss.qualcomm.com>
Collection of layers for the OE-core universe
Main layer maintainer: Khem Raj raj.khem@gmail.com
This repository is a collection of layers to supplement OE-Core with additional packages, Each layer have designated maintainer Please see the respective READMEs in the layer subdirectories