From patchwork Fri Nov 3 06:35:47 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nico Boehr X-Patchwork-Id: 13444357 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (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 1028917CA for ; Fri, 3 Nov 2023 06:41:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b="JXWPtNe3" Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AAA24CA; Thu, 2 Nov 2023 23:41:38 -0700 (PDT) Received: from pps.filterd (m0353726.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 3A36ek84019934; Fri, 3 Nov 2023 06:41:38 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=pp1; bh=XTggoVLwdL6KTjQ0ZrB9ljS56YDf3mMltfkTpGRShd0=; b=JXWPtNe3z54psMdOGduzSIbOZr+aFNVwznmnN8A4bNdkMn6OtHcljeYdQZBdTb+XO6jk JmUgiWyKEtTM6PJc57R0Cy000GoWqDDt9gso+6QzuD2XJlp3S446CtGqCTT9+tM34xOq BYThlBFMYo/CzJaJ3uA3VOEqoZY4C3n+NGiVWTkcfTv4A40JmncO2n5fnoADmbd5Q+hc rf9tp126ofpEpAXPIwPIPdVavTVFTB0oa20GHqFmTFkNHYalf6VMcxxd2m+6+PK+jFkw lG+5cTCTl2P4oseiclBvScH6L23GsLLcnCwQMj0OTu6E0yMt+n5Gw4Bwj6n5OBOW70T+ 5w== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3u4uam0s84-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 03 Nov 2023 06:41:38 +0000 Received: from m0353726.ppops.net (m0353726.ppops.net [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 3A36eu03021554; Fri, 3 Nov 2023 06:41:37 GMT Received: from ppma12.dal12v.mail.ibm.com (dc.9e.1632.ip4.static.sl-reverse.com [50.22.158.220]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3u4uam0s7v-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 03 Nov 2023 06:41:37 +0000 Received: from pps.filterd (ppma12.dal12v.mail.ibm.com [127.0.0.1]) by ppma12.dal12v.mail.ibm.com (8.17.1.19/8.17.1.19) with ESMTP id 3A33x67j000583; Fri, 3 Nov 2023 06:41:36 GMT Received: from smtprelay03.fra02v.mail.ibm.com ([9.218.2.224]) by ppma12.dal12v.mail.ibm.com (PPS) with ESMTPS id 3u1cmtmf2u-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 03 Nov 2023 06:41:36 +0000 Received: from smtpav03.fra02v.mail.ibm.com (smtpav03.fra02v.mail.ibm.com [10.20.54.102]) by smtprelay03.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 3A36fY5P19333740 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 3 Nov 2023 06:41:34 GMT Received: from smtpav03.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id EE4F02005A; Fri, 3 Nov 2023 06:41:33 +0000 (GMT) Received: from smtpav03.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id B95862004E; Fri, 3 Nov 2023 06:41:33 +0000 (GMT) Received: from t35lp63.lnxne.boe (unknown [9.152.108.100]) by smtpav03.fra02v.mail.ibm.com (Postfix) with ESMTP; Fri, 3 Nov 2023 06:41:33 +0000 (GMT) From: Nico Boehr To: frankja@linux.ibm.com, imbrenda@linux.ibm.com, thuth@redhat.com Cc: kvm@vger.kernel.org, linux-s390@vger.kernel.org Subject: [kvm-unit-tests PATCH v1 2/2] s390x: sie: ensure guests are aligned to 2GB Date: Fri, 3 Nov 2023 07:35:47 +0100 Message-ID: <20231103064132.11358-3-nrb@linux.ibm.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20231103064132.11358-1-nrb@linux.ibm.com> References: <20231103064132.11358-1-nrb@linux.ibm.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-GUID: R-lhPlEKTodqQnwdfBGNGIxhlMP-v1r7 X-Proofpoint-ORIG-GUID: X6G9fXNbIKquDtbAiog6nWiAhWSchW1d X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.987,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-11-03_06,2023-11-02_03,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 bulkscore=0 mlxlogscore=999 suspectscore=0 phishscore=0 mlxscore=0 lowpriorityscore=0 clxscore=1015 malwarescore=0 spamscore=0 impostorscore=0 adultscore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2310240000 definitions=main-2311030053 Until now, kvm-unit-tests has aligned guests to 1 MB in the host virtual address space. Unfortunately, some s390x environments require guests to be 2GB aligned in the host virtual address space, preventing kvm-unit-tests which act as a hypervisor from running there. We can't easily put guests at address 0, since we want to be able to run with MSO/MSL without having to maintain separate page tables for the guest physical memory. 2GB is also not a good choice, since the alloc_pages allocator will place its metadata there when the host has more than 2GB of memory. In addition, we also want a bit of space after the end of the host physical memory to be able to catch accesses beyond the end of physical memory. The vmalloc allocator unfortunately allocates memory starting at the highest virtual address which is not suitable for guest memory either due to additional constraints of some environments. The physical page allocator in memalign_pages() is also not a optimal choice, since every test running SIE would then require at least 4GB+1MB of physical memory. This results in a few quite complex allocation requirements, hence add a new function sie_guest_alloc() which allocates memory for a guest and then establishes a properly aligned virtual space mapping. Rework snippet test and sie tests to use the new sie_guest_alloc() function. Signed-off-by: Nico Boehr --- lib/s390x/sie.c | 42 ++++++++++++++++++++++++++++++++++++++++++ lib/s390x/sie.h | 2 ++ lib/s390x/snippet.h | 9 +++------ s390x/sie.c | 4 ++-- 4 files changed, 49 insertions(+), 8 deletions(-) diff --git a/lib/s390x/sie.c b/lib/s390x/sie.c index b44febdeaaac..bd907a0ffefa 100644 --- a/lib/s390x/sie.c +++ b/lib/s390x/sie.c @@ -15,6 +15,8 @@ #include #include #include +#include +#include void sie_expect_validity(struct vm *vm) { @@ -111,6 +113,46 @@ void sie_guest_create(struct vm *vm, uint64_t guest_mem, uint64_t guest_mem_len) vm->sblk->crycbd = (uint32_t)(uintptr_t)vm->crycb; } +/* + * Allocate memory for a guest and map it in virtual address space such that + * it is properly aligned. + * @guest_size the desired size of the guest in bytes. + */ +uint8_t *sie_guest_alloc(uint64_t guest_size) +{ + pgd_t *root; + u8 *guest_phys, *guest_virt; + static unsigned long guest_counter = 1; + unsigned long i; + + setup_vm(); + root = (pgd_t *)(stctg(1) & PAGE_MASK); + + /* + * Start of guest memory in host virtual space needs to be aligned to + * 2GB for some environments. It also can't be at 2GB since the memory + * allocator stores its page_states metadata there. + * Thus we use the next multiple of 4GB after the end of physical + * mapping. This also leaves space after end of physical memory so the + * page immediately after physical memory is guaranteed not to be + * present. + */ + guest_virt = (uint8_t *)ALIGN(get_ram_size() + guest_counter * 4UL * SZ_1G, SZ_2G); + guest_counter++; + + guest_phys = alloc_pages(get_order(guest_size) - 12); + /* + * Establish a new mapping of the guest memory so it can be 2GB aligned + * without actually requiring 2GB physical memory. + */ + for (i = 0; i <= guest_size; i += PAGE_SIZE) { + install_page(root, __pa(guest_phys + i), guest_virt + i); + } + memset(guest_virt, 0, guest_size); + + return guest_virt; +} + /* Frees the memory that was gathered on initialization */ void sie_guest_destroy(struct vm *vm) { diff --git a/lib/s390x/sie.h b/lib/s390x/sie.h index 147cb0f2a556..c1724cf2f67e 100644 --- a/lib/s390x/sie.h +++ b/lib/s390x/sie.h @@ -285,4 +285,6 @@ void sie_guest_sca_create(struct vm *vm); void sie_guest_create(struct vm *vm, uint64_t guest_mem, uint64_t guest_mem_len); void sie_guest_destroy(struct vm *vm); +uint8_t *sie_guest_alloc(uint64_t guest_size); + #endif /* _S390X_SIE_H_ */ diff --git a/lib/s390x/snippet.h b/lib/s390x/snippet.h index 11ec54c379e9..910849aa186c 100644 --- a/lib/s390x/snippet.h +++ b/lib/s390x/snippet.h @@ -125,14 +125,11 @@ static inline void snippet_pv_init(struct vm *vm, const char *gbin, /* Allocates and sets up a snippet based guest */ static inline void snippet_setup_guest(struct vm *vm, bool is_pv) { - u8 *guest; - - /* Allocate 1MB as guest memory */ - guest = alloc_pages(8); - memset(guest, 0, HPAGE_SIZE); + const unsigned long guest_size = SZ_1M; + uint8_t *guest_start = sie_guest_alloc(guest_size); /* Initialize the vm struct and allocate control blocks */ - sie_guest_create(vm, (uint64_t)guest, HPAGE_SIZE); + sie_guest_create(vm, (uint64_t)guest_start, guest_size); if (is_pv) { /* FMT4 needs a ESCA */ diff --git a/s390x/sie.c b/s390x/sie.c index cd3cea10d100..ce5b6069bf0b 100644 --- a/s390x/sie.c +++ b/s390x/sie.c @@ -89,8 +89,8 @@ static void setup_guest(void) { setup_vm(); - /* Allocate 1MB as guest memory */ - guest = alloc_pages(8); + guest = sie_guest_alloc(SZ_1M); + /* The first two pages are the lowcore */ guest_instr = guest + PAGE_SIZE * 2;