From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E09D6422E23; Tue, 28 Jul 2026 17:42:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785260562; cv=none; b=ng2icyrztR/4OX125L+Q91aQayHMXqPHRZhzlIRKsOh9D2vPtaRs6khOUKmJPhlVWXlRenX4FzIUyG+cWESOw5eLymKZRn5qD11b7bRYVWmnMvB+pXQWqOt4rmymUSNbXm7fMvYHIJBdGd6d0tH2UJm2v83bw5mExzYLyNejE3U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785260562; c=relaxed/simple; bh=FQXZ9Stckq8exVW0ERYClKUtBICXrdUIGPHCiL7iLkU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DoJQ2o75QnbhurkADX04By8tVe23+Sr8PEaNQBhHSVzvb+9lJ8Le4Hfyc48RUeBT+Abvx/bqr+3xmZ6kyryE6AUDIm18Uqfy364IYyEo9m800Em5i8M7WkKEEbjiZebE6q8jfttUNB/MxXIX6AfcpRPc18RpBrZ1h0PnMLgEx30= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=GlxOqGlh; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="GlxOqGlh" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 84E9F1F00A3E; Tue, 28 Jul 2026 17:42:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785260559; bh=v39KYB6cskShr4qDx8ePPFvZkoDLUj4MhkwVa0MDDUM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=GlxOqGlhw6vlkJS9T1+1HVktkMl/uN2jnV2bMFywa9HLvJpGYz5uzhNBo/TcjGCYf srOcv443Gc0W+4NpHYtFVgPDQFUEKKwDUUXSxFdI8i5ZnkgFdJYoCnv569tHWM4CmA f3N5ZiOLNkIfjqvHvf38zLsR3N/4D2wtP2oJ0mKWuRGgPYQjhZ2em2acLMEQDiJZI9 FME5VcIrlbViRteiX2dtfMz5vQjZNjKfRQe2nmaPI1RYG9MjwmdRyz7ni2CeBGaLdA biaD/KQzrGr83r9vxMjVjvyS7GpcI6K0vWDjbWvRWzzA9LKvQcW7pbhGkmGdteEs5C drEclUZSp+ARg== From: Yosry Ahmed To: Sean Christopherson Cc: Paolo Bonzini , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Yosry Ahmed , Sashiko Subject: [PATCH v5 02/13] KVM: selftests: Fix RAX and RFLAGS VMCB offsets when running L2 Date: Tue, 28 Jul 2026 17:42:21 +0000 Message-ID: <20260728174232.2423257-3-yosry@kernel.org> X-Mailer: git-send-email 2.55.0.487.gaf234c4eb3-goog In-Reply-To: <20260728174232.2423257-1-yosry@kernel.org> References: <20260728174232.2423257-1-yosry@kernel.org> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit The offsets used (0x170 and 0x1f8) are offsets within vmcb_save_area, not vmcb. The correct offsets should include the base of vmcb_save_area within vmcb (which is 0x400 -- so 0x570 and 0x5f8). Instead of just correcting the offsets, use vmcb->save.rax and vmcb->save.rflags as parameters to the asm block and avoid hardcoding offsets completely. While at it, also use guest_regs.rax directly instead of assuming it's at offset 0 of guest_regs. Note: "+m" must be used for vmcb_rax and vmcb_rflags, as caching those fields in registers would be wrong as the underlying KVM will update them in memory. The same problem was recently fixed (differently) for kvm-unit-tests [1]. [1]https://lore.kernel.org/all/20260521092311.86030-1-pbonzini@redhat.com/ Reported-by: Sashiko Closes: https://sashiko.dev/#/patchset/20260518202514.2037078-1-yosry%40kernel.org?part=1 Signed-off-by: Yosry Ahmed --- tools/testing/selftests/kvm/lib/x86/svm.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) diff --git a/tools/testing/selftests/kvm/lib/x86/svm.c b/tools/testing/selftests/kvm/lib/x86/svm.c index 1445b890986fd..766d15f1d534a 100644 --- a/tools/testing/selftests/kvm/lib/x86/svm.c +++ b/tools/testing/selftests/kvm/lib/x86/svm.c @@ -164,19 +164,22 @@ void run_guest(struct vmcb *vmcb, u64 vmcb_gpa) { asm volatile ( "vmload %[vmcb_gpa]\n\t" - "mov rflags, %%r15\n\t" // rflags - "mov %%r15, 0x170(%[vmcb])\n\t" - "mov guest_regs, %%r15\n\t" // rax - "mov %%r15, 0x1f8(%[vmcb])\n\t" + "mov rflags, %%r15\n\t" + "mov %%r15, %[vmcb_rflags]\n\t" + "mov %[guest_regs_rax], %%r15\n\t" + "mov %%r15, %[vmcb_rax]\n\t" LOAD_GPR_C "vmrun %[vmcb_gpa]\n\t" SAVE_GPR_C - "mov 0x170(%[vmcb]), %%r15\n\t" // rflags + "mov %[vmcb_rflags], %%r15\n\t" "mov %%r15, rflags\n\t" - "mov 0x1f8(%[vmcb]), %%r15\n\t" // rax - "mov %%r15, guest_regs\n\t" + "mov %[vmcb_rax], %%r15\n\t" // rax + "mov %%r15, %[guest_regs_rax]\n\t" "vmsave %[vmcb_gpa]\n\t" - : : [vmcb] "r" (vmcb), [vmcb_gpa] "a" (vmcb_gpa) + : [vmcb_rflags] "+m" (vmcb->save.rflags), + [vmcb_rax] "+m" (vmcb->save.rax), + [guest_regs_rax] "+rm" (guest_regs.rax) + : [vmcb_gpa] "a" (vmcb_gpa) : "r15", "memory"); } -- 2.55.0.487.gaf234c4eb3-goog