From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2F50CCD4F3C for ; Sat, 16 May 2026 18:31:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=6Yr9GGgCQpScYsf1hUYT729pk2Pxrw9m5mYbmydC2KA=; b=CV9S6ccW7KBKmG/VkOc2k13AW5 Oqjps217xv4Xyv4oIJn/o0rUL0jxiQBUNG80OBJi+nq98qE5cydBF86lfr0FoTliJMgGTr9ERKf2k V5heL5Rt5W49FqQHI7YD4KWLM4tdzu2pJBPkyeutaTAqLIMXxZSIjA+o58qMzGkW+JZeSuU8SAe+4 WxPEROZubN1rABmXPzVdjJwA4agOtRI9jBae7ENlFwixvMStpFjeu10qTQBwKTJQ/L2jZX4BhLr/h Cb4Mrj4s1W/iywKT6MNX9Qe5/BrjKgQ7WF9qSOxYFJN2YfH5wzHq+J6YLOZ6WcPU/2k5DD+5RuYvg r+RldMTQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wOJn5-0000000BCRN-2cOz; Sat, 16 May 2026 18:31:11 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wOJn2-0000000BCOk-1OiX for linux-arm-kernel@lists.infradead.org; Sat, 16 May 2026 18:31:09 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 7E1C91CDD; Sat, 16 May 2026 11:31:01 -0700 (PDT) Received: from workstation-e142269.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 134633F85F; Sat, 16 May 2026 11:31:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1778956266; bh=jADMEVZuXP3pAMbKzFIdmO4l26Z49yvuX6i+PGRaGSI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EMtBQNSdsfY93wcLqMuI5+b453PA5kzcOT/rTsqInDh8uabl8rFIATtsowQL62NI9 Wtvcip2D30av12+kf64gPKTyQj/414nurusUCSeb+f0FncU8zzZlwxuyvULAkci6wm C73C1WaSK7A+4LiJnP58PJMMZS9Usa098a5pEUX4= From: Wei-Lin Chang To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev Cc: Paolo Bonzini , Shuah Khan , Marc Zyngier , Oliver Upton , Joey Gouly , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Will Deacon , Itaru Kitayama , Wei-Lin Chang Subject: [PATCH v3 6/9] KVM: arm64: selftests: shadow_stage2: Allocate L2 stack from dedicated pool Date: Sat, 16 May 2026 19:30:00 +0100 Message-ID: <20260516183003.799058-7-weilin.chang@arm.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260516183003.799058-1-weilin.chang@arm.com> References: <20260516183003.799058-1-weilin.chang@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260516_113108_478147_4966ACD0 X-CRM114-Status: GOOD ( 15.02 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Instead of using L1's stack, create a simple page allocator and use that to allocate L2 stack. The allocator will also be used later on when the stage-2 page table generator builds stage-2 mappings for the nested guest (L2). Signed-off-by: Wei-Lin Chang --- .../selftests/kvm/arm64/shadow_stage2.c | 20 ++++++++--- .../selftests/kvm/include/arm64/nested.h | 9 +++++ .../testing/selftests/kvm/lib/arm64/nested.c | 33 +++++++++++++++++++ 3 files changed, 58 insertions(+), 4 deletions(-) diff --git a/tools/testing/selftests/kvm/arm64/shadow_stage2.c b/tools/testing/selftests/kvm/arm64/shadow_stage2.c index cf76a2b0582d..1ad510a38654 100644 --- a/tools/testing/selftests/kvm/arm64/shadow_stage2.c +++ b/tools/testing/selftests/kvm/arm64/shadow_stage2.c @@ -9,12 +9,16 @@ #include "ucall.h" #define XLATE2GPA (0xABCD) -#define L2STACKSZ (0x100) #define L2SUCCESS (0x0) #define L2FAILED (0x1) #define L2SYNC (0x2) +/* Used for L2 stack and guest S2 page tables. */ +#define L2_PAGE_POOL_ADDR (0x80000000) +#define L2_PAGE_POOL_NPAGES (512) +#define L2_PAGE_POOL_MEMSLOT (0x2) + /* * TPIDR_EL2 is used to store vcpu id, so save and restore it. */ @@ -48,14 +52,18 @@ static void guest_code(void) struct hyp_data hyp_data; int ret, i = 0; gpa_t l2_pc, l2_stack_top; - /* force 16-byte alignment for the stack pointer */ - u8 l2_stack[L2STACKSZ] __attribute__((aligned(16))); + struct page_pool pp; GUEST_ASSERT_EQ(get_current_el(), 2); GUEST_PRINTF("vEL2 entry\n"); + pp.start = L2_PAGE_POOL_ADDR; + pp.npages = L2_PAGE_POOL_NPAGES; + pp.current = L2_PAGE_POOL_ADDR; + pp.page_size = get_page_size(); + + l2_stack_top = alloc_page(&pp) + pp.page_size; l2_pc = ucall_translate_to_gpa(l2_guest_code); - l2_stack_top = ucall_translate_to_gpa(&l2_stack[L2STACKSZ]); init_vcpu(&vcpu, l2_pc, l2_stack_top); prepare_hyp(); @@ -96,6 +104,10 @@ int main(void) vcpu = aarch64_vcpu_add(vm, 0, &init, guest_code); kvm_arch_vm_finalize_vcpus(vm); + vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, + L2_PAGE_POOL_ADDR, L2_PAGE_POOL_MEMSLOT, + L2_PAGE_POOL_NPAGES, 0); + while (true) { vcpu_run(vcpu); diff --git a/tools/testing/selftests/kvm/include/arm64/nested.h b/tools/testing/selftests/kvm/include/arm64/nested.h index c10ef4a85be7..8e7d7738b381 100644 --- a/tools/testing/selftests/kvm/include/arm64/nested.h +++ b/tools/testing/selftests/kvm/include/arm64/nested.h @@ -46,6 +46,15 @@ struct hyp_data { struct cpu_context hyp_context; }; +struct page_pool { + gpa_t start; + gpa_t current; + size_t npages; + size_t page_size; +}; + +size_t get_page_size(void); +gpa_t alloc_page(struct page_pool *pp); void prepare_hyp(void); void init_vcpu(struct vcpu *vcpu, gpa_t l2_pc, gpa_t l2_stack_top); int run_l2(struct vcpu *vcpu, struct hyp_data *hyp_data); diff --git a/tools/testing/selftests/kvm/lib/arm64/nested.c b/tools/testing/selftests/kvm/lib/arm64/nested.c index f6c24beb01d0..7f47e340f00d 100644 --- a/tools/testing/selftests/kvm/lib/arm64/nested.c +++ b/tools/testing/selftests/kvm/lib/arm64/nested.c @@ -7,6 +7,39 @@ #include "processor.h" #include "test_util.h" #include +#include + +size_t get_page_size(void) +{ + u64 tcr_el1 = read_sysreg(tcr_el1); + u64 tg0 = SYS_FIELD_GET(TCR_EL1, TG0, tcr_el1); + + switch (tg0) { + case TCR_EL1_TG0_4K: + return SZ_4K; + case TCR_EL1_TG0_16K: + return SZ_16K; + case TCR_EL1_TG0_64K: + return SZ_64K; + default: + GUEST_FAIL("Unexpected tg0 value!\n"); + return 0; + } +} + +gpa_t alloc_page(struct page_pool *pp) +{ + gpa_t page = pp->current; + + pp->current += pp->page_size; + + if ((pp->current - pp->start) / pp->page_size <= pp->npages) { + return page; + } else { + GUEST_FAIL("%s failed!\n", __func__); + return 0; + } +} void prepare_hyp(void) { -- 2.43.0