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 39B4D4CA28E; Thu, 4 Jun 2026 20:36:03 +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=1780605364; cv=none; b=UuUk9nq3YKrFAOF2T+HOq8ddp9l5JySFYtsrNPyyXMmEuXiUO0cO/YWwshRiPyVXZHGm1okPJdlcpOtMJLW+oIw4CnQoOgeX7SqSMUZugtYZb31Rtup+96Jpu9pcgrrSvWYTxROY+LRyTOHpwBQ4tJm6Ke780aPgx4AjhCTl2Ws= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780605364; c=relaxed/simple; bh=jYDcP1j84C4u3f4AWfEcCd2MRGkrmQ+VaR17b6rbbk0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=RAGj96nkSxQewtZ6PogKnc73JA6ESHlzNlnAwQ7mB7bhL+xCxaRsgRglYKtKlY1KW/JoMEUBDwrXwMRoJV/4p+pua+MzhmmH9AQNgZ7zPK3kkNvIQS7oRQ6KIwqBkCGtzVT59Ys+k8St503lCl+Ug0n/quazB9qdIBRidV9i/ps= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ZHNFg7TL; 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="ZHNFg7TL" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E74801F0089C; Thu, 4 Jun 2026 20:36:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780605363; bh=i/TIB41PHxWTXJyWP5r4IoLt45r+2twsxHvTX+LHVr0=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ZHNFg7TL+XnYcX0olqhU6rn7MBVxy0m7tm4oIfzK/uxV0hn8FUhAkMi9KmGpQg8I6 9C8gBxiYKqAbcPv4FyvqlXK2xPC65FI+7NXFBm3t45EFM3F91RNX/unsHMXtM97mfz xpVXikvzOt6f5sH2FQb9lQcrsr5+CIuriLJsWXy4GCR0xAf3lmES2iyroZdNbb2Zde r09a6W+i3A6AFYog2fQOsq9RsrwCfPEqAmOLn2oRpCA7zNOBWYXDB3gW4sNMIICLwy xcBg/mHm9byWxlnt0XplJ06DGLYONH1sE37i59pWNE5SjbaWqpXVO0/Z/vYqujCnCG fwBwXIRu0YZCA== From: Yosry Ahmed To: Sean Christopherson Cc: Paolo Bonzini , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Yosry Ahmed Subject: [PATCH v2 09/10] KVM: selftests: Support running stress save+restore and #PF test in L2 Date: Thu, 4 Jun 2026 20:35:45 +0000 Message-ID: <20260604203546.365658-10-yosry@kernel.org> X-Mailer: git-send-email 2.54.0.1032.g2f8565e1d1-goog In-Reply-To: <20260604203546.365658-1-yosry@kernel.org> References: <20260604203546.365658-1-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 Extend the stress test to allow running the access+#PF code in L2 instead of L1 by adding proper L1 guest code to bootstrap L2. The test runs in nested mode if a '-n' flag is added. Assisted-by: Gemini:gemini-3.1-pro Signed-off-by: Yosry Ahmed --- .../kvm/x86/stress_save_restore_pf_test.c | 75 ++++++++++++++++++- 1 file changed, 73 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/kvm/x86/stress_save_restore_pf_test.c b/tools/testing/selftests/kvm/x86/stress_save_restore_pf_test.c index 92efb7ac9d95f..c285ef093400d 100644 --- a/tools/testing/selftests/kvm/x86/stress_save_restore_pf_test.c +++ b/tools/testing/selftests/kvm/x86/stress_save_restore_pf_test.c @@ -8,10 +8,13 @@ #include #include #include +#include #include "test_util.h" #include "kvm_util.h" #include "processor.h" +#include "svm_util.h" +#include "vmx.h" #define NR_ITERATIONS 500 @@ -25,6 +28,8 @@ do { \ fflush(stdout); \ } while (0) +#define L2_GUEST_STACK_SIZE 64 + #define PTRS_PER_PTE 512 #define PXD_INDEX(vaddr, level) (((vaddr) >> PG_LEVEL_SHIFT(level)) & (PTRS_PER_PTE - 1)) @@ -99,6 +104,41 @@ static void guest_access_memory(void *arg) } } +static void l1_svm_code(struct svm_test_data *svm) +{ + unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE]; + + generic_svm_setup(svm, guest_access_memory, &l2_guest_stack[L2_GUEST_STACK_SIZE]); + + run_guest(svm->vmcb, svm->vmcb_gpa); + GUEST_ASSERT(false); +} + +static void l1_vmx_code(struct vmx_pages *vmx) +{ + unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE]; + + GUEST_ASSERT(prepare_for_vmx_operation(vmx)); + GUEST_ASSERT(load_vmcs(vmx)); + prepare_vmcs(vmx, guest_access_memory, &l2_guest_stack[L2_GUEST_STACK_SIZE]); + + /* Ignore any #PF */ + GUEST_ASSERT(!vmwrite(EXCEPTION_BITMAP, BIT(PF_VECTOR))); + GUEST_ASSERT(!vmwrite(PAGE_FAULT_ERROR_CODE_MASK, 0)); + GUEST_ASSERT(!vmwrite(PAGE_FAULT_ERROR_CODE_MATCH, -1)); + + GUEST_ASSERT(!vmlaunch()); + GUEST_ASSERT(false); +} + +static void l1_guest_code(void *test_data) +{ + if (this_cpu_has(X86_FEATURE_SVM)) + l1_svm_code(test_data); + else + l1_vmx_code(test_data); +} + static void *sigusr_thread_fn(void *arg) { pthread_t vcpu_thread = (pthread_t)arg; @@ -126,6 +166,25 @@ static void vcpu_sigusr_ignore(void) sigaction(SIGUSR1, &sa, NULL); } +static bool parse_args_nested(int argc, char *argv[]) +{ + bool nested = false; + int opt; + + while ((opt = getopt(argc, argv, "n")) != -1) { + switch (opt) { + case 'n': + nested = true; + break; + default: + printf("Usage: %s [-n]\n", argv[0]); + exit(1); + } + } + + return nested; +} + int main(int argc, char *argv[]) { struct kvm_x86_state *state; @@ -136,12 +195,24 @@ int main(int argc, char *argv[]) struct kvm_vm *vm; struct ucall uc; u64 *pgtable; + bool nested; gva_t gva; u64 pte; - vm = vm_create_with_one_vcpu(&vcpu, guest_access_memory); + nested = parse_args_nested(argc, argv); + + vm = vm_create_with_one_vcpu(&vcpu, nested ? l1_guest_code : guest_access_memory); vm_install_exception_handler(vm, PF_VECTOR, guest_pf_handler); + if (nested) { + TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_SVM) || kvm_cpu_has(X86_FEATURE_VMX)); + if (kvm_cpu_has(X86_FEATURE_SVM)) + vcpu_alloc_svm(vm, &gva); + else + vcpu_alloc_vmx(vm, &gva); + vcpu_args_set(vcpu, 1, gva); + } + pte_present_mask = PTE_PRESENT_MASK(&vm->mmu); pte_huge_mask = PTE_HUGE_MASK(&vm->mmu); sync_global_to_guest(vm, pte_present_mask); @@ -216,7 +287,7 @@ int main(int argc, char *argv[]) sync_global_from_guest(vm, guest_faults); TEST_ASSERT(guest_faults > 0, "No guest page faults triggered"); - pr_info("Guest page faults: %lu\n", guest_faults); + pr_info("Guest page faults%s: %lu\n", nested ? " (in L2)" : "", guest_faults); pthread_cancel(sigusr_thread); pthread_join(sigusr_thread, NULL); -- 2.54.0.1032.g2f8565e1d1-goog