On Tue, Feb 14, 2023 at 06:46:01PM +0000, Mingwei Zhang wrote: >After the execution of __tilerelease(), AMX component will be in INIT >state. Therefore, execution of XSAVEC saving the AMX state into memory will >cause the xstate_bv[18] cleared in xheader. However, the xcomp_bv[18] will >remain set. Fix the error in comment. Also, update xsavec() to XSAVEC >because xcomp_bv[18] is set due to the instruction, not the function. >Finally, use XTILEDATA instead 'bit 18' in comments. > >Cc: Jim Mattson <jmattson@xxxxxxxxxx> >Cc: Venkatesh Srinivas <venkateshs@xxxxxxxxxx> >Cc: Aaron Lewis <aaronlewis@xxxxxxxxxx> >Signed-off-by: Mingwei Zhang <mizhang@xxxxxxxxxx> >--- > tools/testing/selftests/kvm/x86_64/amx_test.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > >diff --git a/tools/testing/selftests/kvm/x86_64/amx_test.c b/tools/testing/selftests/kvm/x86_64/amx_test.c >index d506821a5a26..aac727ff7cf8 100644 >--- a/tools/testing/selftests/kvm/x86_64/amx_test.c >+++ b/tools/testing/selftests/kvm/x86_64/amx_test.c >@@ -190,7 +190,10 @@ static void __attribute__((__flatten__)) guest_code(struct tile_config *amx_cfg, > GUEST_SYNC(4); > __tilerelease(); > GUEST_SYNC(5); >- /* bit 18 not in the XCOMP_BV after xsavec() */ >+ /* >+ * After XSAVEC, XTILEDATA is cleared in the xstate_bv but is set in >+ * the xcomp_bv. >+ */ > xstate->header.xstate_bv = XFEATURE_MASK_XTILEDATA; > __xsavec(xstate, XFEATURE_MASK_XTILEDATA); > GUEST_ASSERT(!(xstate->header.xstate_bv & XFEATURE_MASK_XTILEDATA)); maybe it would be better to add another GUEST_ASSERT() to enforce that XTILEDATA is set in the xcomp_bv. >-- >2.39.1.581.gbfd45094c4-goog >
