Arm64 ELF section '.note.stapsdt' uses string format "-4@[sp, NUM]" if the probe is to access data in stack, e.g. below is an example for dumping Arm64 ELF file and shows the argument format: Arguments: -4@[sp, 12] -4@[sp, 8] -4@[sp, 4] Comparing against other archs' argument format, Arm64's argument introduces an extra space character in the middle of square brackets, due to argv_split() uses space as splitter, the argument is wrongly divided into two items. To support Arm64 SDT, this patch fixes up for this case, if any item contains sub string "[sp", concatenates the two continuous items. And adds the detailed explaination in comment. Signed-off-by: Leo Yan <leo.yan@linaro.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexandre Truong <alexandre.truong@arm.com> Cc: Alexis Berlemont <alexis.berlemont@gmail.com> Cc: He Zhe <zhe.he@windriver.com> Cc: Ian Rogers <irogers@google.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: John Garry <john.garry@huawei.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Cc: Thomas Richter <tmricht@linux.ibm.com> Cc: Will Deacon <will@kernel.org> Cc: linux-arm-kernel@lists.infradead.org Link: http://lore.kernel.org/lkml/20201225052751.24513-3-leo.yan@linaro.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>