From 94058f6cde8b887178885954740ac6c866d25eab Mon Sep 17 00:00:00 2001 From: Aurelien Jarno Date: Wed, 15 Dec 2021 23:46:19 +0100 Subject: [PATCH] elf: Fix tst-cpu-features-cpuinfo for KVM guests on some AMD systems [BZ #28704] On KVM guests running on some AMD systems, the IBRS feature is reported as a synthetic feature using the Intel feature, while the cpuinfo entry keeps the same. Handle that by first checking the presence of the Intel feature on AMD systems. Fixes bug 28704. --- sysdeps/x86/tst-cpu-features-cpuinfo.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/sysdeps/x86/tst-cpu-features-cpuinfo.c b/sysdeps/x86/tst-cpu-features-cpuinfo.c index 2d4927f5e5..830aaca2ec 100644 --- a/sysdeps/x86/tst-cpu-features-cpuinfo.c +++ b/sysdeps/x86/tst-cpu-features-cpuinfo.c @@ -169,7 +169,14 @@ do_test (int argc, char **argv) else if (cpu_features->basic.kind == arch_kind_amd) { fails += CHECK_PROC (ibpb, AMD_IBPB); - fails += CHECK_PROC (ibrs, AMD_IBRS); + + /* The IBRS feature on AMD processors is reported using the Intel feature + * on KVM guests (synthetic bit). In both cases the cpuinfo entry is the + * same. */ + if (HAS_CPU_FEATURE (IBRS_IBPB)) + fails += CHECK_PROC (ibrs, IBRS_IBPB); + else + fails += CHECK_PROC (ibrs, AMD_IBRS); fails += CHECK_PROC (stibp, AMD_STIBP); } fails += CHECK_PROC (ibt, IBT); -- 2.43.5