701677b957
addr2line may fail to send expected values causing perf to wait indefinitely. Add a 1 second timeout (twice the timeout for reading from /proc/pid/maps) so that such reads don't cause perf to appear to lock up. There are already checks that the file for addr2line contains a debug section but this isn't always sufficient. The problem was observed when a valid elf file would set the configuration for binutils addr2line, then a later read of vmlinux with ELF debug sections would cause a failing write/read which would block indefinitely. As a service to future readers, if the io hits eof or an error, cleanup the addr2line process. Signed-off-by: Ian Rogers <irogers@google.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: Peter Zijlstra <peterz@infradead.org> Cc: Yang Jihong <yangjihong1@huawei.com> Link: https://lore.kernel.org/r/20230608061812.3715566-2-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.