From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 74A493C871D; Thu, 30 Apr 2026 20:28:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777580885; cv=none; b=bnk5zWeMmdv+vPj4iCd3bojCP7FdgaTrqUcMvUGv9K0fX6rF17EZB/4R/fJxP0VKPvxHZ2MLf1n5uL5lmmN4yH0dpE23g+aRUCzk1KlPqS2kDf6VCjikVxZnB9JNTfZrGVOTj0tlG4G8h1gjFBwA+3qH/NkuloUU51Ka3jsaj7A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777580885; c=relaxed/simple; bh=peLf1xjVZgVyqN2SqYE3bmr9oD1pXuOn5SU63DvVSnA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=HE75y79LoHhO/YbGoGMZG8VE96XmuwECtmYEWrp9XCCfH+hABa1l7cvOoF8yAf1LJRv2+fhb6b+HJPZsqmhZ9Gxj0j+Whqt9Te3Tiv4f0E7kQSlrAIphEwCBcR4a9HQISXn+imFaEWup1yz4IPe6kw0I2VzYDUWZCSCMyrytEmU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=UvQMzCZb; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="UvQMzCZb" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E728FC2BCB4; Thu, 30 Apr 2026 20:28:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1777580885; bh=peLf1xjVZgVyqN2SqYE3bmr9oD1pXuOn5SU63DvVSnA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UvQMzCZbkMZ5rXcASvLqtlRTVWcFycpepD+hRDKxseMzaul9054r1PH4U3Df2nUBs sdHOQv7lgYKr18+9imlmW9dFk1tV+DNqaJNkrIMqlATUJWKKz25PxecxecKYVrcoaG HShW5mL2E+cNJqq+NtL3NoHaxkIOiJqmRM9jW1wgK7ToQgWlzsWd0L6bexwLxqjVZo lNBZyJ2q1i+injrge5jzSEqOgxH+km31k20iePCFv4KuPCOcqI4lXjECbbn1QlPtpz r68I45+ully34gsS/utY2xh+r/BFBvLufp+C3wk5oXbIRuThAyL0PvrESSz5bHdRP7 xiG7yVqC2A/4A== From: Yosry Ahmed To: Sean Christopherson Cc: Paolo Bonzini , Jim Mattson , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Alexander Shishkin , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Yosry Ahmed Subject: [PATCH v5 10/13] KVM: selftests: Refactor allocating guest stack into a helper Date: Thu, 30 Apr 2026 20:27:47 +0000 Message-ID: <20260430202750.3924147-11-yosry@kernel.org> X-Mailer: git-send-email 2.54.0.545.g6539524ca2-goog In-Reply-To: <20260430202750.3924147-1-yosry@kernel.org> References: <20260430202750.3924147-1-yosry@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit In preparation for reusing the logic to allocate stacks for nested guests, refactoring allocating a guest stack and aligning RSP into a helper. No functional change intended. Signed-off-by: Yosry Ahmed --- .../testing/selftests/kvm/lib/x86/processor.c | 45 ++++++++++--------- 1 file changed, 25 insertions(+), 20 deletions(-) diff --git a/tools/testing/selftests/kvm/lib/x86/processor.c b/tools/testing/selftests/kvm/lib/x86/processor.c index b51467d70f6e7..94a1cadb2b26b 100644 --- a/tools/testing/selftests/kvm/lib/x86/processor.c +++ b/tools/testing/selftests/kvm/lib/x86/processor.c @@ -778,6 +778,30 @@ void assert_on_unhandled_exception(struct kvm_vcpu *vcpu) REPORT_GUEST_ASSERT(uc); } +static gva_t vm_alloc_stack(struct kvm_vm *vm, int nr_pages) +{ + int size = nr_pages * getpagesize(); + gva_t stack_gva; + + stack_gva = __vm_alloc(vm, size, DEFAULT_GUEST_STACK_VADDR_MIN, MEM_REGION_DATA); + stack_gva += size; + + /* + * Align stack to match calling sequence requirements in section "The + * Stack Frame" of the System V ABI AMD64 Architecture Processor + * Supplement, which requires the value (%rsp + 8) to be a multiple of + * 16 when control is transferred to the function entry point. + * + * If this code is ever used to launch a vCPU with 32-bit entry point it + * may need to subtract 4 bytes instead of 8 bytes. + */ + TEST_ASSERT(IS_ALIGNED(stack_gva, PAGE_SIZE), + "__vm_alloc() did not provide a page-aligned address"); + stack_gva -= 8; + + return stack_gva; +} + void kvm_arch_vm_post_create(struct kvm_vm *vm, unsigned int nr_vcpus) { int r; @@ -820,27 +844,8 @@ struct kvm_vcpu *vm_arch_vcpu_add(struct kvm_vm *vm, u32 vcpu_id) { struct kvm_mp_state mp_state; struct kvm_regs regs; - gva_t stack_gva; struct kvm_vcpu *vcpu; - stack_gva = __vm_alloc(vm, DEFAULT_STACK_PGS * getpagesize(), - DEFAULT_GUEST_STACK_VADDR_MIN, MEM_REGION_DATA); - - stack_gva += DEFAULT_STACK_PGS * getpagesize(); - - /* - * Align stack to match calling sequence requirements in section "The - * Stack Frame" of the System V ABI AMD64 Architecture Processor - * Supplement, which requires the value (%rsp + 8) to be a multiple of - * 16 when control is transferred to the function entry point. - * - * If this code is ever used to launch a vCPU with 32-bit entry point it - * may need to subtract 4 bytes instead of 8 bytes. - */ - TEST_ASSERT(IS_ALIGNED(stack_gva, PAGE_SIZE), - "__vm_alloc() did not provide a page-aligned address"); - stack_gva -= 8; - vcpu = __vm_vcpu_add(vm, vcpu_id); vcpu_init_cpuid(vcpu, kvm_get_supported_cpuid()); vcpu_init_sregs(vm, vcpu); @@ -849,7 +854,7 @@ struct kvm_vcpu *vm_arch_vcpu_add(struct kvm_vm *vm, u32 vcpu_id) /* Setup guest general purpose registers */ vcpu_regs_get(vcpu, ®s); regs.rflags = regs.rflags | 0x2; - regs.rsp = stack_gva; + regs.rsp = vm_alloc_stack(vm, DEFAULT_STACK_PGS); vcpu_regs_set(vcpu, ®s); /* Setup the MP state */ -- 2.54.0.545.g6539524ca2-goog