From nobody Fri Oct 31 09:41:31 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) client-ip=192.237.175.120; envelope-from=xen-devel-bounces@lists.xenproject.org; helo=lists.xenproject.org; Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org; dmarc=fail(p=quarantine dis=quarantine) header.from=proton.me Return-Path: Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) by mx.zohomail.com with SMTPS id 1747785662787782.363569601403; Tue, 20 May 2025 17:01:02 -0700 (PDT) Received: from list by lists.xenproject.org with outflank-mailman.991281.1375175 (Exim 4.92) (envelope-from ) id 1uHWt2-0002Ve-Ex; Wed, 21 May 2025 00:00:44 +0000 Received: by outflank-mailman (output) from mailman id 991281.1375175; Wed, 21 May 2025 00:00:44 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1uHWt2-0002VX-Br; Wed, 21 May 2025 00:00:44 +0000 Received: by outflank-mailman (input) for mailman id 991281; Wed, 21 May 2025 00:00:43 +0000 Received: from se1-gles-sth1-in.inumbo.com ([159.253.27.254] helo=se1-gles-sth1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1uHWt1-0002HS-Bp for xen-devel@lists.xenproject.org; Wed, 21 May 2025 00:00:43 +0000 Received: from mail-24417.protonmail.ch (mail-24417.protonmail.ch [109.224.244.17]) by se1-gles-sth1.inumbo.com (Halon) with ESMTPS id a2e697ab-35d6-11f0-a2fa-13f23c93f187; Wed, 21 May 2025 02:00:42 +0200 (CEST) X-Outflank-Mailman: Message body and most headers restored to incoming version X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: a2e697ab-35d6-11f0-a2fa-13f23c93f187 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=proton.me; s=protonmail; t=1747785641; x=1748044841; bh=pvUKgvpXykk6QPUGl6S7aKbOTQ27IdteI+qrKZUIs0A=; h=Date:To:From:Cc:Subject:Message-ID:In-Reply-To:References: Feedback-ID:From:To:Cc:Date:Subject:Reply-To:Feedback-ID: Message-ID:BIMI-Selector:List-Unsubscribe:List-Unsubscribe-Post; b=An2iLpdqI15UhAcI0GkxEVPTUsxOoayhPebJIgCaUJqgNGxNUfBN6/rpcWmyKUpuL eHwLLblh4XZ4jXBNavjYH6rneTV4gVsCKmAUZq7JaAealPHfHL/tCA7rPvPjG90XDS LhypG4sCiZhnxa039wX+MphJmBAP/3a8YelI2fqbY/sO9uqbMrcdq9qXxHo1+tidAm UK0AmML5Vj6uNmQxUnMJ4LrcBMjYyfVL0wM71qAFhICdaJGn4UhmkXJcL833V8CORy ISgwaAxsVSA0HhmIBj+O6jbl0BQzapFt19ntZiPbpA7mELbODqdU3JKVy4mMNUh0iR 1Gb/R717yzfZQ== Date: Wed, 21 May 2025 00:00:38 +0000 To: xen-devel@lists.xenproject.org From: dmkhn@proton.me Cc: andrew.cooper3@citrix.com, anthony.perard@vates.tech, jbeulich@suse.com, julien@xen.org, michal.orzel@amd.com, roger.pau@citrix.com, sstabellini@kernel.org, teddy.astie@vates.tech, dmukhin@ford.com Subject: [PATCH v8 1/3] xen/domain: unify domain ID allocation Message-ID: <20250521000024.2944685-2-dmukhin@ford.com> In-Reply-To: <20250521000024.2944685-1-dmukhin@ford.com> References: <20250521000024.2944685-1-dmukhin@ford.com> Feedback-ID: 123220910:user:proton X-Pm-Message-ID: f7978f4ed4e2dd4147763957d2eb90fa79770726 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1747785663608116600 Content-Type: text/plain; charset="utf-8" From: Denis Mukhin Currently, hypervisor code has two different non-system domain ID allocation implementations: (a) Sequential IDs allocation in dom0less Arm code based on max_init_domi= d; (b) Sequential IDs allocation in XEN_DOMCTL_createdomain; does not use max_init_domid (both Arm and x86). It makes sense to have a common helper code for such task across architectu= res (Arm and x86) and between dom0less / toolstack domU allocation. Wrap the domain ID allocation as an arch-independent function domid_alloc()= in common/domain.c based on the bitmap. Allocation algorithm: - If an explicit domain ID is provided, verify its availability and use it = if ID is not used; - If DOMID_INVALID is provided, search the range [0..DOMID_FIRST_RESERVED-1= ], starting from the last used ID and wrapping around as needed. It guarante= es that two consecutive calls will never return the same ID. Also, remove is_free_domid() helper as it is not needed now. No functional change intended. Signed-off-by: Denis Mukhin --- Changes since v7: - Use DOMID_FIRST_RESERVED --- xen/arch/arm/domain_build.c | 17 ++++++--- xen/arch/x86/setup.c | 11 +++--- xen/common/device-tree/dom0less-build.c | 10 +++--- xen/common/domain.c | 47 +++++++++++++++++++++++++ xen/common/domctl.c | 42 +++------------------- xen/include/xen/domain.h | 3 ++ 6 files changed, 80 insertions(+), 50 deletions(-) diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c index b189a7cfae..e9d563c269 100644 --- a/xen/arch/arm/domain_build.c +++ b/xen/arch/arm/domain_build.c @@ -2010,6 +2010,7 @@ void __init create_dom0(void) .grant_opts =3D XEN_DOMCTL_GRANT_version(opt_gnttab_max_version), }; unsigned int flags =3D CDF_privileged | CDF_hardware; + domid_t domid; int rc; =20 /* The vGIC for DOM0 is exactly emulating the hardware GIC */ @@ -2034,19 +2035,25 @@ void __init create_dom0(void) if ( !llc_coloring_enabled ) flags |=3D CDF_directmap; =20 - dom0 =3D domain_create(0, &dom0_cfg, flags); + domid =3D domid_alloc(0); + if ( domid =3D=3D DOMID_INVALID ) + panic("Error allocating domain ID 0\n"); + + dom0 =3D domain_create(domid, &dom0_cfg, flags); if ( IS_ERR(dom0) ) - panic("Error creating domain 0 (rc =3D %ld)\n", PTR_ERR(dom0)); + panic("Error creating domain %d (rc =3D %ld)\n", domid, PTR_ERR(do= m0)); =20 if ( llc_coloring_enabled && (rc =3D dom0_set_llc_colors(dom0)) ) - panic("Error initializing LLC coloring for domain 0 (rc =3D %d)\n"= , rc); + panic("Error initializing LLC coloring for domain %pd (rc =3D %d)\= n", + dom0, rc); =20 if ( alloc_dom0_vcpu0(dom0) =3D=3D NULL ) - panic("Error creating domain 0 vcpu0\n"); + panic("Error creating domain %pdv0\n", dom0); =20 rc =3D construct_dom0(dom0); if ( rc ) - panic("Could not set up DOM0 guest OS (rc =3D %d)\n", rc); + panic("Could not set up guest OS for domain %pd (rc =3D %d)\n", + dom0, rc); =20 set_xs_domain(dom0); } diff --git a/xen/arch/x86/setup.c b/xen/arch/x86/setup.c index 2518954124..ac1c3e669b 100644 --- a/xen/arch/x86/setup.c +++ b/xen/arch/x86/setup.c @@ -1030,8 +1030,11 @@ static struct domain *__init create_dom0(struct boot= _info *bi) if ( iommu_enabled ) dom0_cfg.flags |=3D XEN_DOMCTL_CDF_iommu; =20 - /* Create initial domain. Not d0 for pvshim. */ - bd->domid =3D get_initial_domain_id(); + /* Allocate initial domain ID. Not d0 for pvshim. */ + bd->domid =3D domid_alloc(get_initial_domain_id()); + if ( bd->domid =3D=3D DOMID_INVALID ) + panic("Error allocating domain ID %d\n", get_initial_domain_id()); + d =3D domain_create(bd->domid, &dom0_cfg, pv_shim ? 0 : CDF_privileged | CDF_hardware); if ( IS_ERR(d) ) @@ -1063,7 +1066,7 @@ static struct domain *__init create_dom0(struct boot_= info *bi) =20 if ( (strlen(acpi_param) =3D=3D 0) && acpi_disabled ) { - printk("ACPI is disabled, notifying Domain 0 (acpi=3Doff)\n"); + printk("ACPI is disabled, notifying domain %pd (acpi=3Doff)\n"= , d); safe_strcpy(acpi_param, "off"); } =20 @@ -1078,7 +1081,7 @@ static struct domain *__init create_dom0(struct boot_= info *bi) =20 bd->d =3D d; if ( construct_dom0(bd) !=3D 0 ) - panic("Could not construct domain 0\n"); + panic("Could not construct domain %pd\n", d); =20 bd->cmdline =3D NULL; xfree(cmdline); diff --git a/xen/common/device-tree/dom0less-build.c b/xen/common/device-tr= ee/dom0less-build.c index 2c56f13771..9236dbae11 100644 --- a/xen/common/device-tree/dom0less-build.c +++ b/xen/common/device-tree/dom0less-build.c @@ -850,15 +850,13 @@ void __init create_domUs(void) struct xen_domctl_createdomain d_cfg =3D {0}; unsigned int flags =3D 0U; bool has_dtb =3D false; + domid_t domid; uint32_t val; int rc; =20 if ( !dt_device_is_compatible(node, "xen,domain") ) continue; =20 - if ( (max_init_domid + 1) >=3D DOMID_FIRST_RESERVED ) - panic("No more domain IDs available\n"); - d_cfg.max_evtchn_port =3D 1023; d_cfg.max_grant_frames =3D -1; d_cfg.max_maptrack_frames =3D -1; @@ -981,7 +979,11 @@ void __init create_domUs(void) * very important to use the pre-increment operator to call * domain_create() with a domid > 0. (domid =3D=3D 0 is reserved f= or Dom0) */ - d =3D domain_create(++max_init_domid, &d_cfg, flags); + domid =3D domid_alloc(++max_init_domid); + if ( domid =3D=3D DOMID_INVALID ) + panic("Error allocating ID for domain %s\n", dt_node_name(node= )); + + d =3D domain_create(domid, &d_cfg, flags); if ( IS_ERR(d) ) panic("Error creating domain %s (rc =3D %ld)\n", dt_node_name(node), PTR_ERR(d)); diff --git a/xen/common/domain.c b/xen/common/domain.c index abf1969e60..9c6932c457 100644 --- a/xen/common/domain.c +++ b/xen/common/domain.c @@ -66,6 +66,11 @@ DEFINE_RCU_READ_LOCK(domlist_read_lock); static struct domain *domain_hash[DOMAIN_HASH_SIZE]; struct domain *domain_list; =20 +/* Non-system domain ID allocator. */ +static DEFINE_SPINLOCK(domid_lock); +static DECLARE_BITMAP(domid_bitmap, DOMID_FIRST_RESERVED); +static domid_t domid_last; + /* * Insert a domain into the domlist/hash. This allows the domain to be lo= oked * up by domid, and therefore to be the subject of hypercalls/etc. @@ -1449,6 +1454,8 @@ void domain_destroy(struct domain *d) =20 TRACE_TIME(TRC_DOM0_DOM_REM, d->domain_id); =20 + domid_free(d->domain_id); + /* Remove from the domlist/hash. */ domlist_remove(d); =20 @@ -2405,6 +2412,46 @@ domid_t get_initial_domain_id(void) return hardware_domid; } =20 +domid_t domid_alloc(domid_t domid) +{ + spin_lock(&domid_lock); + + if ( domid < DOMID_FIRST_RESERVED ) + { + if ( __test_and_set_bit(domid, domid_bitmap) ) + domid =3D DOMID_INVALID; + } + else + { + domid =3D find_next_zero_bit(domid_bitmap, DOMID_FIRST_RESERVED, + domid_last); + + if ( domid =3D=3D DOMID_FIRST_RESERVED ) + domid =3D find_next_zero_bit(domid_bitmap, DOMID_FIRST_RESERVE= D, 0); + + if ( domid =3D=3D DOMID_FIRST_RESERVED ) + { + domid =3D DOMID_INVALID; + } + else + { + __set_bit(domid, domid_bitmap); + domid_last =3D domid; + } + } + + spin_unlock(&domid_lock); + + return domid; +} + +void domid_free(domid_t domid) +{ + spin_lock(&domid_lock); + __clear_bit(domid, domid_bitmap); + spin_unlock(&domid_lock); +} + /* * Local variables: * mode: C diff --git a/xen/common/domctl.c b/xen/common/domctl.c index bfe2e1f9f0..8ef0c147c9 100644 --- a/xen/common/domctl.c +++ b/xen/common/domctl.c @@ -49,20 +49,6 @@ static int xenctl_bitmap_to_nodemask(nodemask_t *nodemas= k, MAX_NUMNODES); } =20 -static inline int is_free_domid(domid_t dom) -{ - struct domain *d; - - if ( dom >=3D DOMID_FIRST_RESERVED ) - return 0; - - if ( (d =3D rcu_lock_domain_by_id(dom)) =3D=3D NULL ) - return 1; - - rcu_unlock_domain(d); - return 0; -} - void getdomaininfo(struct domain *d, struct xen_domctl_getdomaininfo *info) { struct vcpu *v; @@ -421,36 +407,18 @@ long do_domctl(XEN_GUEST_HANDLE_PARAM(xen_domctl_t) u= _domctl) =20 case XEN_DOMCTL_createdomain: { - domid_t dom; - static domid_t rover =3D 0; + domid_t domid =3D domid_alloc(op->domain); =20 - dom =3D op->domain; - if ( (dom > 0) && (dom < DOMID_FIRST_RESERVED) ) + if ( domid =3D=3D DOMID_INVALID ) { ret =3D -EEXIST; - if ( !is_free_domid(dom) ) - break; - } - else - { - for ( dom =3D rover + 1; dom !=3D rover; dom++ ) - { - if ( dom =3D=3D DOMID_FIRST_RESERVED ) - dom =3D 1; - if ( is_free_domid(dom) ) - break; - } - - ret =3D -ENOMEM; - if ( dom =3D=3D rover ) - break; - - rover =3D dom; + break; } =20 - d =3D domain_create(dom, &op->u.createdomain, false); + d =3D domain_create(domid, &op->u.createdomain, false); if ( IS_ERR(d) ) { + domid_free(domid); ret =3D PTR_ERR(d); d =3D NULL; break; diff --git a/xen/include/xen/domain.h b/xen/include/xen/domain.h index e10baf2615..8aab05ae93 100644 --- a/xen/include/xen/domain.h +++ b/xen/include/xen/domain.h @@ -38,6 +38,9 @@ void arch_get_domain_info(const struct domain *d, =20 domid_t get_initial_domain_id(void); =20 +domid_t domid_alloc(domid_t domid); +void domid_free(domid_t domid); + /* CDF_* constant. Internal flags for domain creation. */ /* Is this a privileged domain? */ #define CDF_privileged (1U << 0) --=20 2.34.1 From nobody Fri Oct 31 09:41:31 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) client-ip=192.237.175.120; envelope-from=xen-devel-bounces@lists.xenproject.org; helo=lists.xenproject.org; Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org; dmarc=fail(p=quarantine dis=quarantine) header.from=proton.me Return-Path: Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) by mx.zohomail.com with SMTPS id 1747785667403153.90730855170466; Tue, 20 May 2025 17:01:07 -0700 (PDT) Received: from list by lists.xenproject.org with outflank-mailman.991282.1375184 (Exim 4.92) (envelope-from ) id 1uHWt9-0002rH-NZ; Wed, 21 May 2025 00:00:51 +0000 Received: by outflank-mailman (output) from mailman id 991282.1375184; Wed, 21 May 2025 00:00:51 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1uHWt9-0002r8-Ju; Wed, 21 May 2025 00:00:51 +0000 Received: by outflank-mailman (input) for mailman id 991282; Wed, 21 May 2025 00:00:50 +0000 Received: from se1-gles-sth1-in.inumbo.com ([159.253.27.254] helo=se1-gles-sth1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1uHWt8-0002HS-QK for xen-devel@lists.xenproject.org; Wed, 21 May 2025 00:00:50 +0000 Received: from mail-24418.protonmail.ch (mail-24418.protonmail.ch [109.224.244.18]) by se1-gles-sth1.inumbo.com (Halon) with ESMTPS id a7819557-35d6-11f0-a2fa-13f23c93f187; Wed, 21 May 2025 02:00:50 +0200 (CEST) X-Outflank-Mailman: Message body and most headers restored to incoming version X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: a7819557-35d6-11f0-a2fa-13f23c93f187 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=proton.me; s=protonmail; t=1747785649; x=1748044849; bh=gZuziIYnGqs/5mkfDoO7rMHMyTdKJ31HoXIZkb3ogxY=; h=Date:To:From:Cc:Subject:Message-ID:In-Reply-To:References: Feedback-ID:From:To:Cc:Date:Subject:Reply-To:Feedback-ID: Message-ID:BIMI-Selector:List-Unsubscribe:List-Unsubscribe-Post; b=SgfyCp/aOipnEISvQfwIG7qCTfnIQVUPThwCW8JbXmXMjTQTQFW9Pk89lMs8Uiktv O6U+Ng/lsODW24bqQf33QTJiX8ICubq7Vc1Z9qelK7JZiWurRvj2jdxMoIuUClZv9V s+PQ6yK+nq9htiYlseyTLVJcNECUGyl7rZefM5n2NFX5AkZfWjj9M0BCJfADcXprXb tGH8GIAA1S/4EMQdEk4G5QMj5kGRl7MEDepUVdOJRi9iOxhFS5VMLZP9JR4kWdxdUn mfEDs7J/0nx64ZUFWiV4VfdVIIUhSD0KPuepdNR1SXDHbWp/zcvLbUFwF7F3tfI4n5 w+N9N++quiBzA== Date: Wed, 21 May 2025 00:00:44 +0000 To: xen-devel@lists.xenproject.org From: dmkhn@proton.me Cc: andrew.cooper3@citrix.com, anthony.perard@vates.tech, jbeulich@suse.com, julien@xen.org, michal.orzel@amd.com, roger.pau@citrix.com, sstabellini@kernel.org, teddy.astie@vates.tech, dmukhin@ford.com Subject: [PATCH v8 2/3] xen/domain: adjust domain ID allocation for Arm Message-ID: <20250521000024.2944685-3-dmukhin@ford.com> In-Reply-To: <20250521000024.2944685-1-dmukhin@ford.com> References: <20250521000024.2944685-1-dmukhin@ford.com> Feedback-ID: 123220910:user:proton X-Pm-Message-ID: 907ae400060ee37746716b45fa33c0fbb991a03f MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1747785669397116600 Content-Type: text/plain; charset="utf-8" From: Denis Mukhin Remove the hardcoded domain ID 0 allocation for hardware domain and replace= it with a call to get_initial_domain_id() (returns the value of hardware_domid= on Arm). Update domid_alloc(DOMID_INVALID) case to ensure that get_initial_domain_id= () ID is skipped during domain ID allocation to cover domU case in dom0less configuration. That also fixes a potential issue with re-using ID#0 for dom= Us when get_initial_domain_id() returns non-zero. Signed-off-by: Denis Mukhin --- Changes since v7: - use `bool reserved;` in domid_alloc() --- xen/arch/arm/domain_build.c | 4 ++-- xen/common/device-tree/dom0less-build.c | 9 +++------ xen/common/domain.c | 6 ++++++ 3 files changed, 11 insertions(+), 8 deletions(-) diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c index e9d563c269..0ad80b020a 100644 --- a/xen/arch/arm/domain_build.c +++ b/xen/arch/arm/domain_build.c @@ -2035,9 +2035,9 @@ void __init create_dom0(void) if ( !llc_coloring_enabled ) flags |=3D CDF_directmap; =20 - domid =3D domid_alloc(0); + domid =3D domid_alloc(get_initial_domain_id()); if ( domid =3D=3D DOMID_INVALID ) - panic("Error allocating domain ID 0\n"); + panic("Error allocating domain ID %d\n", get_initial_domain_id()); =20 dom0 =3D domain_create(domid, &dom0_cfg, flags); if ( IS_ERR(dom0) ) diff --git a/xen/common/device-tree/dom0less-build.c b/xen/common/device-tr= ee/dom0less-build.c index 9236dbae11..8e38affd0c 100644 --- a/xen/common/device-tree/dom0less-build.c +++ b/xen/common/device-tree/dom0less-build.c @@ -974,14 +974,11 @@ void __init create_domUs(void) =20 arch_create_domUs(node, &d_cfg, flags); =20 - /* - * The variable max_init_domid is initialized with zero, so here i= t's - * very important to use the pre-increment operator to call - * domain_create() with a domid > 0. (domid =3D=3D 0 is reserved f= or Dom0) - */ - domid =3D domid_alloc(++max_init_domid); + domid =3D domid_alloc(DOMID_INVALID); if ( domid =3D=3D DOMID_INVALID ) panic("Error allocating ID for domain %s\n", dt_node_name(node= )); + if ( max_init_domid < domid ) + max_init_domid =3D domid; =20 d =3D domain_create(domid, &d_cfg, flags); if ( IS_ERR(d) ) diff --git a/xen/common/domain.c b/xen/common/domain.c index 9c6932c457..01a65cb35d 100644 --- a/xen/common/domain.c +++ b/xen/common/domain.c @@ -2423,6 +2423,9 @@ domid_t domid_alloc(domid_t domid) } else { + bool reserved =3D __test_and_set_bit(get_initial_domain_id(), + domid_bitmap); + domid =3D find_next_zero_bit(domid_bitmap, DOMID_FIRST_RESERVED, domid_last); =20 @@ -2438,6 +2441,9 @@ domid_t domid_alloc(domid_t domid) __set_bit(domid, domid_bitmap); domid_last =3D domid; } + + if ( !reserved ) + __clear_bit(reserved, domid_bitmap); } =20 spin_unlock(&domid_lock); --=20 2.34.1 From nobody Fri Oct 31 09:41:31 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) client-ip=192.237.175.120; envelope-from=xen-devel-bounces@lists.xenproject.org; helo=lists.xenproject.org; Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org; dmarc=fail(p=quarantine dis=quarantine) header.from=proton.me Return-Path: Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) by mx.zohomail.com with SMTPS id 1747785672424459.8075082971552; Tue, 20 May 2025 17:01:12 -0700 (PDT) Received: from list by lists.xenproject.org with outflank-mailman.991287.1375195 (Exim 4.92) (envelope-from ) id 1uHWtK-0003RI-2w; Wed, 21 May 2025 00:01:02 +0000 Received: by outflank-mailman (output) from mailman id 991287.1375195; Wed, 21 May 2025 00:01:02 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1uHWtK-0003RB-06; Wed, 21 May 2025 00:01:02 +0000 Received: by outflank-mailman (input) for mailman id 991287; Wed, 21 May 2025 00:01:00 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1uHWtI-0003ED-MZ for xen-devel@lists.xenproject.org; Wed, 21 May 2025 00:01:00 +0000 Received: from mail-4322.protonmail.ch (mail-4322.protonmail.ch [185.70.43.22]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id acc4adee-35d6-11f0-b892-0df219b8e170; Wed, 21 May 2025 02:00:58 +0200 (CEST) X-Outflank-Mailman: Message body and most headers restored to incoming version X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: acc4adee-35d6-11f0-b892-0df219b8e170 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=proton.me; s=protonmail; t=1747785658; x=1748044858; bh=dyWE4g9RjoCjxwzz+tbMoGFTSyVkuUaSnQCT8L45dwk=; h=Date:To:From:Cc:Subject:Message-ID:In-Reply-To:References: Feedback-ID:From:To:Cc:Date:Subject:Reply-To:Feedback-ID: Message-ID:BIMI-Selector:List-Unsubscribe:List-Unsubscribe-Post; b=TbSqvMPGyLUnSry1J+SA51tgHl9mOQP1t0Z66lTI0S24Aq08/Ua1vmdjgH2RDku7E sl8IGfAc3N5H79SR4ElyeXcO8O17UnC5cPV7tUlNyh+16f6UaiTGbuTzIkJe1iGiRo jwbxC0HR/jEB+Q1e3DqcfER4N7t0gVFtPXwq72yk0T0VMS/5PVJ0FBneAYeanUo3Pn 8iq4J0T3uyvrGZFPwKjpFkNgd6EhB223+U1kNBrSXw7YjNiA5YH2AxDnldgZ5Mk/3V HafsksnYXhKXE/sUiIl9CziZ9CxFYb5/wnNJsJAzwCsSSmRxvpJmMrPCC1fDGnJTFJ 3I+BmkfnGzPKg== Date: Wed, 21 May 2025 00:00:52 +0000 To: xen-devel@lists.xenproject.org From: dmkhn@proton.me Cc: andrew.cooper3@citrix.com, anthony.perard@vates.tech, jbeulich@suse.com, julien@xen.org, michal.orzel@amd.com, roger.pau@citrix.com, sstabellini@kernel.org, teddy.astie@vates.tech, dmukhin@ford.com Subject: [PATCH v8 3/3] xen/domain: introduce CONFIG_MAX_DOMID Message-ID: <20250521000024.2944685-4-dmukhin@ford.com> In-Reply-To: <20250521000024.2944685-1-dmukhin@ford.com> References: <20250521000024.2944685-1-dmukhin@ford.com> Feedback-ID: 123220910:user:proton X-Pm-Message-ID: 4bd2800df5799a7a1e01ada611e97a9ce4808730 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1747785673837116600 Content-Type: text/plain; charset="utf-8" From: Denis Mukhin Embedded deployments of Xen do not need to have support for more than dozen= of domains. Introduce build-time configuration option to limit the number of domains du= ring run-time. Also, move DOMID_FIRST_RESERVED compile-time check from Arm to common code. Suggested-by: Julien Grall Signed-off-by: Denis Mukhin --- This is an RFC. Changes since v7: - moved DOMID_FIRST_RESERVED compile-time checks to common code - changed description for MAX_DOMID Kconfig option --- xen/arch/arm/tee/ffa.c | 3 +-- xen/arch/x86/cpu/mcheck/mce.c | 2 +- xen/arch/x86/cpu/vpmu.c | 2 +- xen/common/Kconfig | 7 +++++++ xen/common/domain.c | 21 ++++++++++++--------- xen/common/sched/core.c | 4 ++-- xen/drivers/passthrough/vtd/iommu.c | 2 +- xen/include/public/domctl.h | 2 +- 8 files changed, 26 insertions(+), 17 deletions(-) diff --git a/xen/arch/arm/tee/ffa.c b/xen/arch/arm/tee/ffa.c index 3bbdd7168a..7417ce6bed 100644 --- a/xen/arch/arm/tee/ffa.c +++ b/xen/arch/arm/tee/ffa.c @@ -331,10 +331,9 @@ static int ffa_domain_init(struct domain *d) * reserved for the hypervisor and we only support secure endpoints us= ing * FF-A IDs with BIT 15 set to 1 so make sure those are not used by Xe= n. */ - BUILD_BUG_ON(DOMID_FIRST_RESERVED >=3D UINT16_MAX); BUILD_BUG_ON((DOMID_MASK & BIT(15, U)) !=3D 0); =20 - if ( d->domain_id >=3D DOMID_FIRST_RESERVED ) + if ( d->domain_id >=3D CONFIG_MAX_DOMID ) return -ERANGE; =20 ctx =3D xzalloc(struct ffa_ctx); diff --git a/xen/arch/x86/cpu/mcheck/mce.c b/xen/arch/x86/cpu/mcheck/mce.c index 1c348e557d..ee8ddd33b0 100644 --- a/xen/arch/x86/cpu/mcheck/mce.c +++ b/xen/arch/x86/cpu/mcheck/mce.c @@ -1493,7 +1493,7 @@ long do_mca(XEN_GUEST_HANDLE_PARAM(xen_mc_t) u_xen_mc) d =3D rcu_lock_domain_by_any_id(mc_msrinject->mcinj_domid); if ( d =3D=3D NULL ) { - if ( mc_msrinject->mcinj_domid >=3D DOMID_FIRST_RESERVED ) + if ( mc_msrinject->mcinj_domid >=3D CONFIG_MAX_DOMID ) return x86_mcerr("do_mca inject: incompatible flag " "MC_MSRINJ_F_GPADDR with domain %d", -EINVAL, domid); diff --git a/xen/arch/x86/cpu/vpmu.c b/xen/arch/x86/cpu/vpmu.c index c28192ea26..67d423e088 100644 --- a/xen/arch/x86/cpu/vpmu.c +++ b/xen/arch/x86/cpu/vpmu.c @@ -174,7 +174,7 @@ void vpmu_do_interrupt(void) * in XENPMU_MODE_ALL, for everyone. */ if ( (vpmu_mode & XENPMU_MODE_ALL) || - (sampled->domain->domain_id >=3D DOMID_FIRST_RESERVED) ) + (sampled->domain->domain_id >=3D CONFIG_MAX_DOMID) ) { sampling =3D choose_hwdom_vcpu(); if ( !sampling ) diff --git a/xen/common/Kconfig b/xen/common/Kconfig index 6d43be2e6e..66b91840f2 100644 --- a/xen/common/Kconfig +++ b/xen/common/Kconfig @@ -576,4 +576,11 @@ config BUDDY_ALLOCATOR_SIZE Amount of memory reserved for the buddy allocator to serve Xen heap, working alongside the colored one. =20 +config MAX_DOMID + int "Maximum number of user domains" + range 1 32752 + default 32752 + help + Specifies the maximum number of domains a user can create. + endmenu diff --git a/xen/common/domain.c b/xen/common/domain.c index 01a65cb35d..204b71d096 100644 --- a/xen/common/domain.c +++ b/xen/common/domain.c @@ -68,7 +68,7 @@ struct domain *domain_list; =20 /* Non-system domain ID allocator. */ static DEFINE_SPINLOCK(domid_lock); -static DECLARE_BITMAP(domid_bitmap, DOMID_FIRST_RESERVED); +static DECLARE_BITMAP(domid_bitmap, CONFIG_MAX_DOMID); static domid_t domid_last; =20 /* @@ -155,7 +155,7 @@ int domain_init_states(void) ASSERT(rw_is_write_locked_by_me(¤t->domain->event_lock)); =20 dom_state_changed =3D xvzalloc_array(unsigned long, - BITS_TO_LONGS(DOMID_FIRST_RESERVED)= ); + BITS_TO_LONGS(CONFIG_MAX_DOMID)); if ( !dom_state_changed ) return -ENOMEM; =20 @@ -235,7 +235,7 @@ int get_domain_state(struct xen_domctl_get_domain_state= *info, struct domain *d, while ( dom_state_changed ) { dom =3D find_first_bit(dom_state_changed, DOMID_MASK + 1); - if ( dom >=3D DOMID_FIRST_RESERVED ) + if ( dom >=3D CONFIG_MAX_DOMID ) break; if ( test_and_clear_bit(dom, dom_state_changed) ) { @@ -824,7 +824,7 @@ struct domain *domain_create(domid_t domid, /* Sort out our idea of is_hardware_domain(). */ if ( (flags & CDF_hardware) || domid =3D=3D hardware_domid ) { - if ( hardware_domid < 0 || hardware_domid >=3D DOMID_FIRST_RESERVE= D ) + if ( hardware_domid < 0 || hardware_domid >=3D CONFIG_MAX_DOMID ) panic("The value of hardware_dom must be a valid domain ID\n"); =20 /* late_hwdom is only allowed for dom0. */ @@ -2414,9 +2414,12 @@ domid_t get_initial_domain_id(void) =20 domid_t domid_alloc(domid_t domid) { + BUILD_BUG_ON(DOMID_FIRST_RESERVED >=3D UINT16_MAX); + BUILD_BUG_ON(DOMID_FIRST_RESERVED < CONFIG_MAX_DOMID); + spin_lock(&domid_lock); =20 - if ( domid < DOMID_FIRST_RESERVED ) + if ( domid < CONFIG_MAX_DOMID ) { if ( __test_and_set_bit(domid, domid_bitmap) ) domid =3D DOMID_INVALID; @@ -2426,13 +2429,13 @@ domid_t domid_alloc(domid_t domid) bool reserved =3D __test_and_set_bit(get_initial_domain_id(), domid_bitmap); =20 - domid =3D find_next_zero_bit(domid_bitmap, DOMID_FIRST_RESERVED, + domid =3D find_next_zero_bit(domid_bitmap, CONFIG_MAX_DOMID, domid_last); =20 - if ( domid =3D=3D DOMID_FIRST_RESERVED ) - domid =3D find_next_zero_bit(domid_bitmap, DOMID_FIRST_RESERVE= D, 0); + if ( domid =3D=3D CONFIG_MAX_DOMID ) + domid =3D find_next_zero_bit(domid_bitmap, CONFIG_MAX_DOMID, 0= ); =20 - if ( domid =3D=3D DOMID_FIRST_RESERVED ) + if ( domid =3D=3D CONFIG_MAX_DOMID ) { domid =3D DOMID_INVALID; } diff --git a/xen/common/sched/core.c b/xen/common/sched/core.c index 9043414290..f1bfb6f6a2 100644 --- a/xen/common/sched/core.c +++ b/xen/common/sched/core.c @@ -867,7 +867,7 @@ int sched_init_domain(struct domain *d, unsigned int po= olid) int ret; =20 ASSERT(d->cpupool =3D=3D NULL); - ASSERT(d->domain_id < DOMID_FIRST_RESERVED); + ASSERT(d->domain_id < CONFIG_MAX_DOMID); =20 if ( (ret =3D cpupool_add_domain(d, poolid)) ) return ret; @@ -891,7 +891,7 @@ int sched_init_domain(struct domain *d, unsigned int po= olid) =20 void sched_destroy_domain(struct domain *d) { - ASSERT(d->domain_id < DOMID_FIRST_RESERVED); + ASSERT(d->domain_id < CONFIG_MAX_DOMID); =20 if ( d->cpupool ) { diff --git a/xen/drivers/passthrough/vtd/iommu.c b/xen/drivers/passthrough/= vtd/iommu.c index c55f02c97e..5df85ca629 100644 --- a/xen/drivers/passthrough/vtd/iommu.c +++ b/xen/drivers/passthrough/vtd/iommu.c @@ -1509,7 +1509,7 @@ int domain_context_mapping_one( =20 prev_did =3D context_domain_id(lctxt); domid =3D did_to_domain_id(iommu, prev_did); - if ( domid < DOMID_FIRST_RESERVED ) + if ( domid < CONFIG_MAX_DOMID ) prev_dom =3D rcu_lock_domain_by_id(domid); else if ( pdev ? domid =3D=3D pdev->arch.pseudo_domid : domid > DO= MID_MASK ) prev_dom =3D rcu_lock_domain(dom_io); diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h index 5b2063eed9..0c14c30c1b 100644 --- a/xen/include/public/domctl.h +++ b/xen/include/public/domctl.h @@ -36,7 +36,7 @@ =20 /* * NB. xen_domctl.domain is an IN/OUT parameter for this operation. - * If it is specified as an invalid value (0 or >=3D DOMID_FIRST_RESERVED), + * If it is specified as an invalid value (0 or >=3D CONFIG_MAX_DOMID), * an id is auto-allocated and returned. */ /* XEN_DOMCTL_createdomain */ --=20 2.34.1