Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753323AbbLJF4y (ORCPT ); Thu, 10 Dec 2015 00:56:54 -0500 Received: from szxga03-in.huawei.com ([119.145.14.66]:16907 "EHLO szxga03-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752138AbbLJF4n (ORCPT ); Thu, 10 Dec 2015 00:56:43 -0500 From: Wang Nan To: , , CC: , , , Wang Nan , Arnaldo Carvalho de Melo , Namhyung Kim Subject: [PATCH 1/2] perf tests: Fix incorrect free and false TEST_OK result Date: Thu, 10 Dec 2015 05:52:47 +0000 Message-ID: <1449726768-79624-1-git-send-email-wangnan0@huawei.com> X-Mailer: git-send-email 1.8.3.4 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.107.193.248] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020206.5669140B.016C,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2013-05-26 15:14:31, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: f4c9a3cd7df753a5c9407d2952dc821b Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 10159 Lines: 315 Commit cc1121ab9687d660cc02f50b1a4974112f87a8e6 ('perf machine: Fix machine.vmlinux_maps to make sure to clear the old one') reveals a bug in 'perf test' that in all test cases which use setup_fake_machine() incorrectly call free() when failure, because all users of setup_fake_machine() use static allocated 'machines' structure, but setup_fake_machine() calls machine__delete() which try to free() it. If a normal user try those test cases this problem can be seen: $ cat /proc/sys/kernel/kptr_restrict 1 $ ./perf test 'hist' 15: Test matching and linking multiple hists :*** Error in `./perf': munmap_chunk(): invalid pointer: 0x00007ffd6e900090 *** ======= Backtrace: ========= /lib64/libc.so.6(+0x6eeef)[0x7fcec97e1eef] /lib64/libc.so.6(+0x78cae)[0x7fcec97ebcae] ./perf(setup_fake_machine+0x1cd)[0x4721ad] ./perf(test__hists_link+0xbf)[0x472d3f] ./perf[0x4648df] ./perf(cmd_test+0x589)[0x464ec9] ./perf[0x47fd11] ./perf(main+0x5f6)[0x432b96] /lib64/libc.so.6(__libc_start_main+0xf5)[0x7fcec9794bd5] ./perf[0x432cc5] ======= Memory map: ======== ... 25: Test filtering hist entries :*** Error in `./perf': munmap_chunk(): invalid pointer: 0x00007ffd6e900080 *** ======= Backtrace: ========= /lib64/libc.so.6(+0x6eeef)[0x7fcec97e1eef] /lib64/libc.so.6(+0x78cae)[0x7fcec97ebcae] ./perf(setup_fake_machine+0x1cd)[0x4721ad] ./perf(test__hists_filter+0xc6)[0x4730f6] ./perf[0x4648df] ./perf(cmd_test+0x589)[0x464ec9] ./perf[0x47fd11] ./perf(main+0x5f6)[0x432b96] /lib64/libc.so.6(__libc_start_main+0xf5)[0x7fcec9794bd5] ./perf[0x432cc5] ======= Memory map: ======== ... ... Actually, all users of 'machines__init()' should avoid calling machine__delete(). We can further add a flag in machine structure to enforce this restriction. After changing machine__delete() to machine__exit() another problem arises: $ ./perf test 'hist' 15: Test matching and linking multiple hists : Ok 25: Test filtering hist entries : Ok 28: Test output sorting of hist entries : Ok 29: Test cumulation of child hist entries : Ok The result is not true: $ ./perf test -v 'hist' 15: Test matching and linking multiple hists : --- start --- test child forked, pid 17657 Not enough memory for machine setup Not enough memory for machine setup test child finished with 0 ---- end ---- Test matching and linking multiple hists: Ok 25: Test filtering hist entries : --- start --- test child forked, pid 17658 Not enough memory for machine setup Not enough memory for machine setup test child finished with 0 ---- end ---- Test filtering hist entries: Ok 28: Test output sorting of hist entries : --- start --- test child forked, pid 17659 Not enough memory for machine setup Not enough memory for machine setup test child finished with 0 ---- end ---- Test output sorting of hist entries: Ok 29: Test cumulation of child hist entries : --- start --- test child forked, pid 17660 Not enough memory for machine setup Not enough memory for machine setup test child finished with 0 ---- end ---- Test cumulation of child hist entries: Ok Because the test body is not executed at all. The reason is that *ALL* hists test cases forget to reset err after using it to hold an error code: err = TEST_FAIL; ... err = parse_events(evlist, "cpu-clock", NULL); if (err) goto out; /* err is already 0 here */ ... machine = setup_fake_machine(&machines); if (!machine) goto out; ... out: ... return err; This patch ensure err is reset. In case when kptr_restrict prevent normal user get kernel address, this test should be skipped, not fail. This patch use linux/err.h to store error code in return value of setup_fake_machine(), and let 'EACCES' to indicate this problem. Also, the debug message 'Not enough memory for machine setup' is not true and should be fixed. Here is the final result: $ ./perf test 'hist' 15: Test matching and linking multiple hists : Skip 25: Test filtering hist entries : Skip 28: Test output sorting of hist entries : Skip 29: Test cumulation of child hist entries : Skip $ ./perf test -v 'hist' 15: Test matching and linking multiple hists : --- start --- test child forked, pid 20177 Failed to create kernel maps Hint: Check /proc/sys/kernel/kptr_restrict. Failed for machine setup test child finished with -2 ---- end ---- Test matching and linking multiple hists: Skip 25: Test filtering hist entries ... $ sudo ./perf test hist 15: Test matching and linking multiple hists : Ok 25: Test filtering hist entries : Ok 28: Test output sorting of hist entries : Ok 29: Test cumulation of child hist entries : Ok Signed-off-by: Wang Nan Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Masami Hiramatsu Cc: Namhyung Kim --- tools/perf/tests/hists_common.c | 15 ++++++++++----- tools/perf/tests/hists_common.h | 1 + tools/perf/tests/hists_cumulate.c | 6 +++++- tools/perf/tests/hists_filter.c | 6 +++++- tools/perf/tests/hists_link.c | 6 +++++- tools/perf/tests/hists_output.c | 6 +++++- 6 files changed, 31 insertions(+), 9 deletions(-) diff --git a/tools/perf/tests/hists_common.c b/tools/perf/tests/hists_common.c index 46f453b..4cd8cad 100644 --- a/tools/perf/tests/hists_common.c +++ b/tools/perf/tests/hists_common.c @@ -81,14 +81,19 @@ struct machine *setup_fake_machine(struct machines *machines) { struct machine *machine = machines__find(machines, HOST_KERNEL_ID); size_t i; + int err = -ENOMEM; if (machine == NULL) { pr_debug("Not enough memory for machine setup\n"); - return NULL; + return ERR_PTR(-ENOMEM); } if (machine__create_kernel_maps(machine)) { - pr_debug("Not enough memory for machine setup\n"); + pr_debug("Failed to create kernel maps\n"); + if (symbol_conf.kptr_restrict) { + pr_debug("Hint: Check /proc/sys/kernel/kptr_restrict.\n"); + err = -EACCES; + } goto out; } @@ -153,10 +158,10 @@ struct machine *setup_fake_machine(struct machines *machines) return machine; out: - pr_debug("Not enough memory for machine setup\n"); + pr_debug("Failed for machine setup\n"); machine__delete_threads(machine); - machine__delete(machine); - return NULL; + machine__exit(machine); + return ERR_PTR(err); } void print_hists_in(struct hists *hists) diff --git a/tools/perf/tests/hists_common.h b/tools/perf/tests/hists_common.h index 888254e..0252eae 100644 --- a/tools/perf/tests/hists_common.h +++ b/tools/perf/tests/hists_common.h @@ -1,5 +1,6 @@ #ifndef __PERF_TESTS__HISTS_COMMON_H__ #define __PERF_TESTS__HISTS_COMMON_H__ +#include struct machine; struct machines; diff --git a/tools/perf/tests/hists_cumulate.c b/tools/perf/tests/hists_cumulate.c index 8292948..c211075 100644 --- a/tools/perf/tests/hists_cumulate.c +++ b/tools/perf/tests/hists_cumulate.c @@ -706,13 +706,17 @@ int test__hists_cumulate(int subtest __maybe_unused) err = parse_events(evlist, "cpu-clock", NULL); if (err) goto out; + err = TEST_FAIL; machines__init(&machines); /* setup threads/dso/map/symbols also */ machine = setup_fake_machine(&machines); - if (!machine) + if (IS_ERR(machine)) { + if (PTR_ERR(machine) == -EACCES) + err = TEST_SKIP; goto out; + } if (verbose > 1) machine__fprintf(machine, stderr); diff --git a/tools/perf/tests/hists_filter.c b/tools/perf/tests/hists_filter.c index ccb5b49..795a04d 100644 --- a/tools/perf/tests/hists_filter.c +++ b/tools/perf/tests/hists_filter.c @@ -120,6 +120,7 @@ int test__hists_filter(int subtest __maybe_unused) err = parse_events(evlist, "task-clock", NULL); if (err) goto out; + err = TEST_FAIL; /* default sort order (comm,dso,sym) will be used */ if (setup_sorting() < 0) @@ -129,8 +130,11 @@ int test__hists_filter(int subtest __maybe_unused) /* setup threads/dso/map/symbols also */ machine = setup_fake_machine(&machines); - if (!machine) + if (IS_ERR(machine)) { + if (PTR_ERR(machine) == -EACCES) + err = TEST_SKIP; goto out; + } if (verbose > 1) machine__fprintf(machine, stderr); diff --git a/tools/perf/tests/hists_link.c b/tools/perf/tests/hists_link.c index 6243e2b..f5f37ef9 100644 --- a/tools/perf/tests/hists_link.c +++ b/tools/perf/tests/hists_link.c @@ -293,6 +293,7 @@ int test__hists_link(int subtest __maybe_unused) if (err) goto out; + err = TEST_FAIL; /* default sort order (comm,dso,sym) will be used */ if (setup_sorting() < 0) goto out; @@ -301,8 +302,11 @@ int test__hists_link(int subtest __maybe_unused) /* setup threads/dso/map/symbols also */ machine = setup_fake_machine(&machines); - if (!machine) + if (IS_ERR(machine)) { + if (PTR_ERR(machine) == -EACCES) + err = TEST_SKIP; goto out; + } if (verbose > 1) machine__fprintf(machine, stderr); diff --git a/tools/perf/tests/hists_output.c b/tools/perf/tests/hists_output.c index 248beec..cc570cf 100644 --- a/tools/perf/tests/hists_output.c +++ b/tools/perf/tests/hists_output.c @@ -597,13 +597,17 @@ int test__hists_output(int subtest __maybe_unused) err = parse_events(evlist, "cpu-clock", NULL); if (err) goto out; + err = TEST_FAIL; machines__init(&machines); /* setup threads/dso/map/symbols also */ machine = setup_fake_machine(&machines); - if (!machine) + if (IS_ERR(machine)) { + if (PTR_ERR(machine) == -EACCES) + err = TEST_SKIP; goto out; + } if (verbose > 1) machine__fprintf(machine, stderr); -- 1.8.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/