Commit 409b4fa7 authored Apr 03, 2023 by Adrian Hunter Committed by Greg Kroah-Hartman May 17, 2023

perf auxtrace: Fix address filter entire kernel size



commit 1f9f33ccf0320be21703d9195dd2b36a1c9a07cb upstream.

kallsyms is not completely in address order.

In find_entire_kern_cb(), calculate the kernel end from the maximum
address not the last symbol.

Example:

 Before:

    $ sudo cat /proc/kallsyms | grep ' [twTw] ' | tail -1
    ffffffffc00b8bd0 t bpf_prog_6deef7357e7b4530    [bpf]
    $ sudo cat /proc/kallsyms | grep ' [twTw] ' | sort | tail -1
    ffffffffc15e0cc0 t iwl_mvm_exit [iwlmvm]
    $ perf.d093603a05aa record -v --kcore -e intel_pt// --filter 'filter *' -- uname |& grep filter
    Address filter: filter 0xffffffff93200000/0x2ceba000

 After:

    $ perf.8fb0f7a01f8e record -v --kcore -e intel_pt// --filter 'filter *' -- uname |& grep filter
    Address filter: filter 0xffffffff93200000/0x2e3e2000

Fixes: 1b36c03e ("perf record: Add support for using symbols in address filters")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230403154831.8651-2-adrian.hunter@intel.com


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent b4b94b25

tools/perf/util/auxtrace.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -1793,6 +1793,7 @@ static int find_entire_kern_cb(void arg, const char name __maybe_unused,
		char type, u64 start)
		{
		struct sym_args *args = arg;
		u64 size;

		if (!kallsyms__is_function(type))
		return 0;
		@@ -1802,7 +1803,9 @@ static int find_entire_kern_cb(void arg, const char name __maybe_unused,
		args->start = start;
		}
		/* Don't know exactly where the kernel ends, so we add a page */
		args->size = round_up(start, page_size) + page_size - args->start;
		size = round_up(start, page_size) + page_size - args->start;
		if (size > args->size)
		args->size = size;

		return 0;
		}