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f00bb757ed
__msg, __regex and __xlated tags are based on
__attribute__((btf_decl_tag("..."))) annotations.
Clang de-duplicates such annotations, e.g. the following
two sequences of tags are identical in final BTF:
/* seq A */ /* seq B */
__tag("foo") __tag("foo")
__tag("bar") __tag("bar")
__tag("foo")
Fix this by adding a unique suffix for each tag using __COUNTER__
pre-processor macro. E.g. here is a new definition for __msg:
#define __msg(msg) \
__attribute__((btf_decl_tag("comment:test_expect_msg=" XSTR(__COUNTER__) "=" msg)))
Using this definition the "seq A" from example above is translated to
BTF as follows:
[..] DECL_TAG 'comment:test_expect_msg=0=foo' type_id=X component_idx=-1
[..] DECL_TAG 'comment:test_expect_msg=1=bar' type_id=X component_idx=-1
[..] DECL_TAG 'comment:test_expect_msg=2=foo' type_id=X component_idx=-1
Surprisingly, this bug affects a single existing test:
verifier_spill_fill/old_stack_misc_vs_cur_ctx_ptr,
where sequence of identical messages was expected in the log.
Fixes: 537c3f66ea ("selftests/bpf: add generic BPF program tester-loader")
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240820102357.3372779-4-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.