From: Adrian Hunter adrian.hunter@intel.com
stable inclusion from linux-4.19.149 commit a63689c06a6dd5c0cf2a9221927b9b1b2b2bb9c1
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[ Upstream commit 61f82e3fb697a8e85f22fdec786528af73dc36d1 ]
In the absence of any modules, no "modules" map is created, but there are other executable pages to map, due to eBPF JIT, kprobe or ftrace. Map them by recognizing that the first "module" symbol is not necessarily from a module, and adjust the map accordingly.
Signed-off-by: Adrian Hunter adrian.hunter@intel.com Cc: Alexander Shishkin alexander.shishkin@linux.intel.com Cc: Borislav Petkov bp@alien8.de Cc: H. Peter Anvin hpa@zytor.com Cc: Jiri Olsa jolsa@redhat.com Cc: Leo Yan leo.yan@linaro.org Cc: Mark Rutland mark.rutland@arm.com Cc: Masami Hiramatsu mhiramat@kernel.org Cc: Mathieu Poirier mathieu.poirier@linaro.org Cc: Peter Zijlstra peterz@infradead.org Cc: Steven Rostedt (VMware) rostedt@goodmis.org Cc: x86@kernel.org Link: http://lore.kernel.org/lkml/20200512121922.8997-10-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- tools/perf/util/symbol-elf.c | 7 +++++++ 1 file changed, 7 insertions(+)
diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c index a701a8a48f00..166c621e0223 100644 --- a/tools/perf/util/symbol-elf.c +++ b/tools/perf/util/symbol-elf.c @@ -1421,6 +1421,7 @@ struct kcore_copy_info { u64 first_symbol; u64 last_symbol; u64 first_module; + u64 first_module_symbol; u64 last_module_symbol; size_t phnum; struct list_head phdrs; @@ -1497,6 +1498,8 @@ static int kcore_copy__process_kallsyms(void *arg, const char *name, char type, return 0;
if (strchr(name, '[')) { + if (!kci->first_module_symbol || start < kci->first_module_symbol) + kci->first_module_symbol = start; if (start > kci->last_module_symbol) kci->last_module_symbol = start; return 0; @@ -1694,6 +1697,10 @@ static int kcore_copy__calc_maps(struct kcore_copy_info *kci, const char *dir, kci->etext += page_size; }
+ if (kci->first_module_symbol && + (!kci->first_module || kci->first_module_symbol < kci->first_module)) + kci->first_module = kci->first_module_symbol; + kci->first_module = round_down(kci->first_module, page_size);
if (kci->last_module_symbol) {