Commit-ID: f1031c8d33a8c40d4cac26e58c37d9fba0e31a8a
Gitweb: https://git.kernel.org/tip/f1031c8d33a8c40d4cac26e58c37d9fba0e31a8a
Author: Kim Phillips <kim.phillips@xxxxxxx>
AuthorDate: Thu, 14 Dec 2017 17:52:42 -0600
Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Wed, 27 Dec 2017 12:15:58 -0300
perf probe arm64: Fix symbol fixup issues due to ELF type
On an arm64 machine running a CONFIG_RANDOMIZE_BASE=y kernel, perf
kernel symbol resolution fails. Debugging saw symsrc_init calling the
default elf__needs_adjust_symbols() where checks for an ET_DYN (3)
ehdr.e_type failed when they should have succeeded.
Fix by adopting powerpc version of the weak elf__needs_adjust_symbols()
function, as done in commit d2332098331f ("perf probe ppc: Fix symbol
fixup issues due to ELF type").
Prior to this patch, perf test 1 would fail:
$ sudo oldperf test -v 1 |& head
1: vmlinux symtab matches kallsyms :
test child forked, pid 33374
Looking at the vmlinux_path (8 entries long)
Using /usr/lib/debug/boot/vmlinux for symbols
ERR : 0xfffe0000100f1000: do_undefinstr not on kallsyms
ERR : 0xfffe0000100f1320: do_sysinstr not on kallsyms
ERR : 0xfffe0000100f13b0: do_debug_exception not on kallsyms
ERR : 0xfffe0000100f1498: do_mem_abort not on kallsyms
ERR : 0xfffe0000100f1580: do_sp_pc_abort not on kallsyms
...
After applying this patch, perf test 1 now succeeds:
$ sudo ./newperf test -v 1 |& head
1: vmlinux symtab matches kallsyms :
test child forked, pid 33378
Looking at the vmlinux_path (8 entries long)
Using /usr/lib/debug/boot/vmlinux for symbols
WARN: 0xffff000008081000: diff name v: do_undefinstr k: __exception_text_start
WARN: 0xffff0000080819e8: diff name v: __irqentry_text_end k: __softirqentry_text_start
WARN: 0xffff000008081d08: diff name v: __entry_text_start k: __softirqentry_text_end
WARN: 0xffff00000809db5c: diff name v: flush_icache_range k: __flush_cache_user_range
WARN: 0xffff000008101908: diff name v: sys_ni_syscall k: sys_vm86old
...
Signed-off-by: Kim Phillips <kim.phillips@xxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Ganapatrao Kulkarni <ganapatrao.kulkarni@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Naveen N. Rao <naveen.n.rao@xxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Will Deacon <will.deacon@xxxxxxx>
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/20171214175242.e30450f17f93ad675d968fa3@xxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/arch/arm64/util/Build | 1 +
tools/perf/arch/arm64/util/sym-handling.c | 22 ++++++++++++++++++++++
2 files changed, 23 insertions(+)
diff --git a/tools/perf/arch/arm64/util/Build b/tools/perf/arch/arm64/util/Build
index b1ab72d..e04f6cd 100644
--- a/tools/perf/arch/arm64/util/Build
+++ b/tools/perf/arch/arm64/util/Build
@@ -1,4 +1,5 @@
libperf-y += header.o
+libperf-y += sym-handling.o
libperf-$(CONFIG_DWARF) += dwarf-regs.o
libperf-$(CONFIG_LOCAL_LIBUNWIND) += unwind-libunwind.o
diff --git a/tools/perf/arch/arm64/util/sym-handling.c b/tools/perf/arch/arm64/util/sym-handling.c
new file mode 100644
index 0000000..0051b1e
--- /dev/null
+++ b/tools/perf/arch/arm64/util/sym-handling.c
@@ -0,0 +1,22 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * Copyright (C) 2015 Naveen N. Rao, IBM Corporation
+ */
+
+#include "debug.h"
+#include "symbol.h"
+#include "map.h"
+#include "probe-event.h"
+#include "probe-file.h"
+
+#ifdef HAVE_LIBELF_SUPPORT
+bool elf__needs_adjust_symbols(GElf_Ehdr ehdr)
+{
+ return ehdr.e_type == ET_EXEC ||
+ ehdr.e_type == ET_REL ||
+ ehdr.e_type == ET_DYN;
+}
+#endif
--
To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
|