Commit bec357a4 authored by Mingwei Zhang's avatar Mingwei Zhang Committed by Sean Christopherson
Browse files

KVM: selftests: Fix an error in comment of amx_test 



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@google.com>
Cc: Venkatesh Srinivas <venkateshs@google.com>
Cc: Aaron Lewis <aaronlewis@google.com>
Signed-off-by: default avatarMingwei Zhang <mizhang@google.com>
Link: https://lore.kernel.org/r/20230221163655.920289-4-mizhang@google.com


Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent 5de4a376

tools/testing/selftests/kvm/x86_64/amx_test.c

+4 −1
Original line number Diff line number Diff line
@@ -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));