From b15e7490a1efd4c0f54434c3a85ced1b6b536b7a Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Thu, 21 Sep 2023 10:16:41 -0700 Subject: [PATCH 1/3] KVM: selftests: Treat %llx like %lx when formatting guest printf Treat %ll* formats the same as %l* formats when processing printfs from the guest so that using e.g. %llx instead of %lx generates the expected output. Ideally, unexpected formats would generate compile-time warnings or errors, but it's not at all obvious how to actually accomplish that. Alternatively, guest_vsnprintf() could assert on an unexpected format, but since the vast majority of printfs are for failed guest asserts, getting *something* printed is better than nothing. E.g. before ==== Test Assertion Failure ==== x86_64/private_mem_conversions_test.c:265: mem[i] == 0 pid=4286 tid=4290 errno=4 - Interrupted system call 1 0x0000000000401c74: __test_mem_conversions at private_mem_conversions_test.c:336 2 0x00007f3aae6076da: ?? ??:0 3 0x00007f3aae32161e: ?? ??:0 Expected 0x0 at offset 0 (gpa 0x%lx), got 0x0 and after ==== Test Assertion Failure ==== x86_64/private_mem_conversions_test.c:265: mem[i] == 0 pid=5664 tid=5668 errno=4 - Interrupted system call 1 0x0000000000401c74: __test_mem_conversions at private_mem_conversions_test.c:336 2 0x00007fbe180076da: ?? ??:0 3 0x00007fbe17d2161e: ?? ??:0 Expected 0x0 at offset 0 (gpa 0x100000000), got 0xcc Fixes: e5119382499c ("KVM: selftests: Add guest_snprintf() to KVM selftests") Cc: Aaron Lewis Link: https://lore.kernel.org/r/20230921171641.3641776-1-seanjc@google.com Signed-off-by: Sean Christopherson --- tools/testing/selftests/kvm/lib/guest_sprintf.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/tools/testing/selftests/kvm/lib/guest_sprintf.c b/tools/testing/selftests/kvm/lib/guest_sprintf.c index c4a69d8aeb68..74627514c4d4 100644 --- a/tools/testing/selftests/kvm/lib/guest_sprintf.c +++ b/tools/testing/selftests/kvm/lib/guest_sprintf.c @@ -200,6 +200,13 @@ int guest_vsnprintf(char *buf, int n, const char *fmt, va_list args) ++fmt; } + /* + * Play nice with %llu, %llx, etc. KVM selftests only support + * 64-bit builds, so just treat %ll* the same as %l*. + */ + if (qualifier == 'l' && *fmt == 'l') + ++fmt; + /* default base */ base = 10; From 332c4d90a09c2cdc59f88d6a6c58c1601403b891 Mon Sep 17 00:00:00 2001 From: Like Xu Date: Thu, 14 Sep 2023 17:48:03 +0800 Subject: [PATCH 2/3] KVM: selftests: Remove obsolete and incorrect test case metadata Delete inaccurate descriptions and obsolete metadata for test cases. It adds zero value, and has a non-zero chance of becoming stale and misleading in the future. No functional changes intended. Suggested-by: Sean Christopherson Signed-off-by: Like Xu Link: https://lore.kernel.org/r/20230914094803.94661-1-likexu@tencent.com Signed-off-by: Sean Christopherson --- tools/testing/selftests/kvm/include/ucall_common.h | 2 -- tools/testing/selftests/kvm/lib/x86_64/apic.c | 2 -- tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c | 2 -- tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.c | 2 -- tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.sh | 1 - tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c | 4 ---- tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c | 4 ---- 7 files changed, 17 deletions(-) diff --git a/tools/testing/selftests/kvm/include/ucall_common.h b/tools/testing/selftests/kvm/include/ucall_common.h index 112bc1da732a..ce33d306c2cb 100644 --- a/tools/testing/selftests/kvm/include/ucall_common.h +++ b/tools/testing/selftests/kvm/include/ucall_common.h @@ -1,7 +1,5 @@ /* SPDX-License-Identifier: GPL-2.0-only */ /* - * tools/testing/selftests/kvm/include/kvm_util.h - * * Copyright (C) 2018, Google LLC. */ #ifndef SELFTEST_KVM_UCALL_COMMON_H diff --git a/tools/testing/selftests/kvm/lib/x86_64/apic.c b/tools/testing/selftests/kvm/lib/x86_64/apic.c index 7168e25c194e..89153a333e83 100644 --- a/tools/testing/selftests/kvm/lib/x86_64/apic.c +++ b/tools/testing/selftests/kvm/lib/x86_64/apic.c @@ -1,7 +1,5 @@ // SPDX-License-Identifier: GPL-2.0-only /* - * tools/testing/selftests/kvm/lib/x86_64/processor.c - * * Copyright (C) 2021, Google LLC. */ diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c b/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c index e446d76d1c0c..6c1278562090 100644 --- a/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c +++ b/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c @@ -1,7 +1,5 @@ // SPDX-License-Identifier: GPL-2.0-only /* - * KVM_GET/SET_* tests - * * Copyright (C) 2022, Red Hat, Inc. * * Tests for Hyper-V extensions to SVM. diff --git a/tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.c b/tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.c index 7f36c32fa760..18ac5c1952a3 100644 --- a/tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.c +++ b/tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.c @@ -1,7 +1,5 @@ // SPDX-License-Identifier: GPL-2.0-only /* - * tools/testing/selftests/kvm/nx_huge_page_test.c - * * Usage: to be run via nx_huge_page_test.sh, which does the necessary * environment setup and teardown * diff --git a/tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.sh b/tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.sh index 0560149e66ed..7cbb409801ee 100755 --- a/tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.sh +++ b/tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.sh @@ -4,7 +4,6 @@ # Wrapper script which performs setup and cleanup for nx_huge_pages_test. # Makes use of root privileges to set up huge pages and KVM module parameters. # -# tools/testing/selftests/kvm/nx_huge_page_test.sh # Copyright (C) 2022, Google LLC. set -e diff --git a/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c b/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c index 5b669818e39a..59c7304f805e 100644 --- a/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c +++ b/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c @@ -1,10 +1,6 @@ // SPDX-License-Identifier: GPL-2.0-only /* - * svm_vmcall_test - * * Copyright © 2021 Amazon.com, Inc. or its affiliates. - * - * Xen shared_info / pvclock testing */ #include "test_util.h" diff --git a/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c b/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c index 05898ad9f4d9..9ec9ab60b63e 100644 --- a/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c +++ b/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c @@ -1,10 +1,6 @@ // SPDX-License-Identifier: GPL-2.0-only /* - * svm_vmcall_test - * * Copyright © 2021 Amazon.com, Inc. or its affiliates. - * - * Xen shared_info / pvclock testing */ #include "test_util.h" From 6313e096dbfaf1377ba8f5f8ccd720cc36c576c6 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Wed, 4 Oct 2023 17:29:54 -0700 Subject: [PATCH 3/3] KVM: selftests: Zero-initialize entire test_result in memslot perf test MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Zero-initialize the entire test_result structure used by memslot_perf_test instead of zeroing only the fields used to guard the pr_info() calls. gcc 13.2.0 is a bit overzealous and incorrectly thinks that rbestslottime's slot_runtime may be used uninitialized. In file included from memslot_perf_test.c:25: memslot_perf_test.c: In function ‘main’: include/test_util.h:31:22: error: ‘rbestslottime.slot_runtime.tv_nsec’ may be used uninitialized [-Werror=maybe-uninitialized] 31 | #define pr_info(...) printf(__VA_ARGS__) | ^~~~~~~~~~~~~~~~~~~ memslot_perf_test.c:1127:17: note: in expansion of macro ‘pr_info’ 1127 | pr_info("Best slot setup time for the whole test area was %ld.%.9lds\n", | ^~~~~~~ memslot_perf_test.c:1092:28: note: ‘rbestslottime.slot_runtime.tv_nsec’ was declared here 1092 | struct test_result rbestslottime; | ^~~~~~~~~~~~~ include/test_util.h:31:22: error: ‘rbestslottime.slot_runtime.tv_sec’ may be used uninitialized [-Werror=maybe-uninitialized] 31 | #define pr_info(...) printf(__VA_ARGS__) | ^~~~~~~~~~~~~~~~~~~ memslot_perf_test.c:1127:17: note: in expansion of macro ‘pr_info’ 1127 | pr_info("Best slot setup time for the whole test area was %ld.%.9lds\n", | ^~~~~~~ memslot_perf_test.c:1092:28: note: ‘rbestslottime.slot_runtime.tv_sec’ was declared here 1092 | struct test_result rbestslottime; | ^~~~~~~~~~~~~ That can't actually happen, at least not without the "result" structure in test_loop() also being used uninitialized, which gcc doesn't complain about, as writes to rbestslottime are all-or-nothing, i.e. slottimens can't be non-zero without slot_runtime being written. if (!data->mem_size && (!rbestslottime->slottimens || result.slottimens < rbestslottime->slottimens)) *rbestslottime = result; Zero-initialize the structures to make gcc happy even though this is likely a compiler bug. The cost to do so is negligible, both in terms of code and runtime overhead. The only downside is that the compiler won't warn about legitimate usage of "uninitialized" data, e.g. the test could end up consuming zeros instead of useful data. However, given that the test is quite mature and unlikely to see substantial changes, the odds of introducing such bugs are relatively low, whereas being able to compile KVM selftests with -Werror detects issues on a regular basis. Reviewed-by: Maciej S. Szmigiero Reviewed-by: Philippe Mathieu-Daudé Link: https://lore.kernel.org/r/20231005002954.2887098-1-seanjc@google.com Signed-off-by: Sean Christopherson --- tools/testing/selftests/kvm/memslot_perf_test.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/tools/testing/selftests/kvm/memslot_perf_test.c b/tools/testing/selftests/kvm/memslot_perf_test.c index 20eb2e730800..8698d1ab60d0 100644 --- a/tools/testing/selftests/kvm/memslot_perf_test.c +++ b/tools/testing/selftests/kvm/memslot_perf_test.c @@ -1033,9 +1033,8 @@ static bool test_loop(const struct test_data *data, struct test_result *rbestruntime) { uint64_t maxslots; - struct test_result result; + struct test_result result = {}; - result.nloops = 0; if (!test_execute(targs->nslots, &maxslots, targs->seconds, data, &result.nloops, &result.slot_runtime, &result.guest_runtime)) { @@ -1089,7 +1088,7 @@ int main(int argc, char *argv[]) .seconds = 5, .runs = 1, }; - struct test_result rbestslottime; + struct test_result rbestslottime = {}; int tctr; if (!check_memory_sizes()) @@ -1098,11 +1097,10 @@ int main(int argc, char *argv[]) if (!parse_args(argc, argv, &targs)) return -1; - rbestslottime.slottimens = 0; for (tctr = targs.tfirst; tctr <= targs.tlast; tctr++) { const struct test_data *data = &tests[tctr]; unsigned int runctr; - struct test_result rbestruntime; + struct test_result rbestruntime = {}; if (tctr > targs.tfirst) pr_info("\n"); @@ -1110,7 +1108,6 @@ int main(int argc, char *argv[]) pr_info("Testing %s performance with %i runs, %d seconds each\n", data->name, targs.runs, targs.seconds); - rbestruntime.runtimens = 0; for (runctr = 0; runctr < targs.runs; runctr++) if (!test_loop(data, &targs, &rbestslottime, &rbestruntime))