From b15e7490a1efd4c0f54434c3a85ced1b6b536b7a Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Thu, 21 Sep 2023 10:16:41 -0700 Subject: [PATCH] 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;