On Thu, 27 Feb 2020 17:20:39 +0100 Alexandre Ghiti alex@ghiti.fr wrote:
On 2/27/20 4:42 PM, Masami Hiramatsu wrote:
Do not depend on dwfl_module_addrsym() because it can fail on user-space shared libraries.
Actually, same bug was fixed by commit 664fee3dc379 ("perf probe: Do not use dwfl_module_addrsym if dwarf_diename finds symbol name"), but commit 07d369857808 ("perf probe: Fix wrong address verification) reverted to get actual symbol address from symtab.
This fixes it again by getting symbol address from DIE, and only if the DIE has only address range, it uses dwfl_module_addrsym().
Fixes: 07d369857808 ("perf probe: Fix wrong address verification) Reported-by: Alexandre Ghiti alex@ghiti.fr Signed-off-by: Masami Hiramatsu mhiramat@kernel.org
tools/perf/util/probe-finder.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c index 1c817add6ca4..e4cff49384f4 100644 --- a/tools/perf/util/probe-finder.c +++ b/tools/perf/util/probe-finder.c @@ -637,14 +637,19 @@ static int convert_to_trace_point(Dwarf_Die *sp_die, Dwfl_Module *mod, return -EINVAL; }
- /* Try to get actual symbol name from symtab */
- symbol = dwfl_module_addrsym(mod, paddr, &sym, NULL);
- if (dwarf_entrypc(sp_die, &eaddr) == 0) {
/* If the DIE has entrypc, use it. */symbol = dwarf_diename(sp_die);- } else {
/* Try to get actual symbol name and address from symtab */symbol = dwfl_module_addrsym(mod, paddr, &sym, NULL);eaddr = sym.st_value;- } if (!symbol) { pr_warning("Failed to find symbol at 0x%lx\n", (unsigned long)paddr); return -ENOENT; }
- eaddr = sym.st_value;
tp->offset = (unsigned long)(paddr - eaddr); tp->address = (unsigned long)paddr;
I have just tested your patch, that fixes the issue, so you can add:
Tested-by: Alexandre Ghiti alex@ghiti.fr
Thanks Alexandre, Arnaldo, could you also pick this for fix?
Thank you,