8dc26b6f71
The addr2line process is sent an address then multiple function, filename:line "records" are read. To detect the end of output a ',' is sent and for llvm-addr2line a ',' is then read back showing the end of addrline's output. For binutils addr2line the ',' translates to address 0 and we expect the bogus filename marker "??:0" (see filename_split) to be sent from addr2line. For some kernels address 0 may have a mapping and so a seemingly valid inline output is given and breaking the sentinel discovery: ``` $ addr2line -e vmlinux -f -i , __per_cpu_start ./arch/x86/kernel/cpu/common.c:1850 ``` To avoid this problem enable the address dumping for addr2line (the -a option). If an address of 0x0000000000000000 is read then this is the sentinel value working around the problem above. The filename_split still needs to check for "??:0" as bogus non-zero addresses also need handling. Reported-by: Changbin Du <changbin.du@huawei.com> Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: Changbin Du <changbin.du@huawei.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tom Rix <trix@redhat.com> Cc: llvm@lists.linux.dev Link: https://lore.kernel.org/r/20230613034817.1356114-3-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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 Restructured Text 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.