From: Mingwei Zhang Date: Tue, 21 Feb 2023 16:36:50 +0000 (+0000) Subject: KVM: selftests: Verify XTILE_DATA in XSTATE isn't affected by IA32_XFD X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=bfc5afc37c9dba85f8c057fb85109a72e72d64a5;p=linux.git KVM: selftests: Verify XTILE_DATA in XSTATE isn't affected by IA32_XFD Add asserts to verify the XSTATE metadata for XTILE_DATA isn't affected by disabling AMX tile data via IA32_XFD. XFD doesn't intercept XSAVE, it only prevents setting bits in XCR0, i.e. regardless of XFD, AMX state is managed by XSAVE/XRSTOR as long as the corresponding bits are set XCR0. Signed-off-by: Mingwei Zhang Link: https://lore.kernel.org/r/20230221163655.920289-9-mizhang@google.com [sean: massage changelog] Signed-off-by: Sean Christopherson --- diff --git a/tools/testing/selftests/kvm/x86_64/amx_test.c b/tools/testing/selftests/kvm/x86_64/amx_test.c index cd0491cc7c8c9..e6bc6cd108dc0 100644 --- a/tools/testing/selftests/kvm/x86_64/amx_test.c +++ b/tools/testing/selftests/kvm/x86_64/amx_test.c @@ -201,6 +201,16 @@ static void __attribute__((__flatten__)) guest_code(struct tile_config *amx_cfg, /* xfd=0x40000, disable amx tiledata */ wrmsr(MSR_IA32_XFD, XFEATURE_MASK_XTILEDATA); + + /* + * XTILEDATA is cleared in xstate_bv but set in xcomp_bv, this property + * remains the same even when amx tiledata is disabled by IA32_XFD. + */ + xstate->header.xstate_bv = XFEATURE_MASK_XTILEDATA; + __xsavec(xstate, XFEATURE_MASK_XTILEDATA); + GUEST_ASSERT(!(xstate->header.xstate_bv & XFEATURE_MASK_XTILEDATA)); + GUEST_ASSERT((xstate->header.xcomp_bv & XFEATURE_MASK_XTILEDATA)); + GUEST_SYNC(6); GUEST_ASSERT(rdmsr(MSR_IA32_XFD) == XFEATURE_MASK_XTILEDATA); set_tilecfg(amx_cfg);