From patchwork Mon Dec 16 17:37:31 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Julien Grall X-Patchwork-Id: 22538 Return-Path: X-Original-To: linaro@patches.linaro.org Delivered-To: linaro@patches.linaro.org Received: from mail-qc0-f198.google.com (mail-qc0-f198.google.com [209.85.216.198]) by ip-10-151-82-157.ec2.internal (Postfix) with ESMTPS id 0EEAF23FC6 for ; Mon, 16 Dec 2013 17:37:54 +0000 (UTC) Received: by mail-qc0-f198.google.com with SMTP id e9sf9311650qcy.9 for ; Mon, 16 Dec 2013 09:37:53 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:delivered-to:from:to:cc:subject :date:message-id:in-reply-to:references:x-original-sender :x-original-authentication-results:precedence:mailing-list:list-id :list-post:list-help:list-archive:list-unsubscribe; bh=kiUSGMXMah5Da6AQ8Og82yrjRVJmsOZigtgatCI/sbs=; b=B3+tbouObrp47FLEyFBBNVVjkQJM+whPFzwzTqs55EKd+A66cc1q2gu6RwCdXZYiOx gBqqruDrS/nwzk5IhqtPlzsyCilGHm/0wE1qYZcD7Yg7qdvdyiZJ3Hboqzsajxa97XUP WjMOgEb3NHhQyaObIJLSWhp7EjR8Fw7z1nA8sS2hNDq2jHSM3h33uy+VRlK+7D0jDQzo 4kv7rZOnfvis1KEiOaq5241MiF8DaNfG0x//WByFwef0ypFXkg6TrY6BmHeWXwjBXtll HVWwshzGrnxbSPLCm/ErxWjIKaMfM1W4bEBE5fuHogk3Qswzazsqsq9qpJ4Fo9cs3aYE v2TA== X-Gm-Message-State: ALoCoQl0K/P4m9YZAy7dn6Vmdeg3cN9EU1DV3TdVY1BrD3RDcd8ZmT4ZmuZKJRPZqE411HS+h3NE X-Received: by 10.236.73.164 with SMTP id v24mr5661607yhd.24.1387215473902; Mon, 16 Dec 2013 09:37:53 -0800 (PST) MIME-Version: 1.0 X-BeenThere: patchwork-forward@linaro.org Received: by 10.49.131.162 with SMTP id on2ls2170365qeb.73.gmail; Mon, 16 Dec 2013 09:37:53 -0800 (PST) X-Received: by 10.220.7.147 with SMTP id d19mr1726809vcd.47.1387215473782; Mon, 16 Dec 2013 09:37:53 -0800 (PST) Received: from mail-vc0-f182.google.com (mail-vc0-f182.google.com [209.85.220.182]) by mx.google.com with ESMTPS id a6si4155832vdp.26.2013.12.16.09.37.53 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 16 Dec 2013 09:37:53 -0800 (PST) Received-SPF: neutral (google.com: 209.85.220.182 is neither permitted nor denied by best guess record for domain of patch+caf_=patchwork-forward=linaro.org@linaro.org) client-ip=209.85.220.182; Received: by mail-vc0-f182.google.com with SMTP id lc6so3345268vcb.41 for ; Mon, 16 Dec 2013 09:37:53 -0800 (PST) X-Received: by 10.52.165.131 with SMTP id yy3mr7482755vdb.25.1387215473703; Mon, 16 Dec 2013 09:37:53 -0800 (PST) X-Forwarded-To: patchwork-forward@linaro.org X-Forwarded-For: patch@linaro.org patchwork-forward@linaro.org Delivered-To: patches@linaro.org Received: by 10.220.174.196 with SMTP id u4csp6134vcz; Mon, 16 Dec 2013 09:37:53 -0800 (PST) X-Received: by 10.15.22.137 with SMTP id f9mr8951427eeu.30.1387215472378; Mon, 16 Dec 2013 09:37:52 -0800 (PST) Received: from mail-ea0-f171.google.com (mail-ea0-f171.google.com [209.85.215.171]) by mx.google.com with ESMTPS id s42si774728eew.161.2013.12.16.09.37.51 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 16 Dec 2013 09:37:52 -0800 (PST) Received-SPF: neutral (google.com: 209.85.215.171 is neither permitted nor denied by best guess record for domain of julien.grall@linaro.org) client-ip=209.85.215.171; Received: by mail-ea0-f171.google.com with SMTP id h10so2375047eak.16 for ; Mon, 16 Dec 2013 09:37:51 -0800 (PST) X-Received: by 10.14.5.12 with SMTP id 12mr18271966eek.9.1387215471882; Mon, 16 Dec 2013 09:37:51 -0800 (PST) Received: from belegaer.uk.xensource.com. ([185.25.64.249]) by mx.google.com with ESMTPSA id e3sm44674680eeg.11.2013.12.16.09.37.50 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 16 Dec 2013 09:37:50 -0800 (PST) From: Julien Grall To: xen-devel@lists.xenproject.org Cc: patches@linaro.org, ian.campbell@citrix.com, tim@xen.org, stefano.stabellini@citrix.com, Julien Grall Subject: [PATCH v5 09/10] xen/arm: Set foreign page type to p2m_map_foreign Date: Mon, 16 Dec 2013 17:37:31 +0000 Message-Id: <1387215452-10951-10-git-send-email-julien.grall@linaro.org> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1387215452-10951-1-git-send-email-julien.grall@linaro.org> References: <1387215452-10951-1-git-send-email-julien.grall@linaro.org> X-Removed-Original-Auth: Dkim didn't pass. X-Original-Sender: julien.grall@linaro.org X-Original-Authentication-Results: mx.google.com; spf=neutral (google.com: 209.85.220.182 is neither permitted nor denied by best guess record for domain of patch+caf_=patchwork-forward=linaro.org@linaro.org) smtp.mail=patch+caf_=patchwork-forward=linaro.org@linaro.org Precedence: list Mailing-list: list patchwork-forward@linaro.org; contact patchwork-forward+owners@linaro.org List-ID: X-Google-Group-Id: 836684582541 List-Post: , List-Help: , List-Archive: List-Unsubscribe: , Xen needs to know that the current page belongs to another domain. Also take a reference to this page. The current process to add a foreign page is: 1) get the page from the foreign p2m 2) take a reference on the page with the foreign domain in parameters 3) add the page to the current domain p2m If the foreign domain drops the page: - before 2), get_page will return NULL because the page doesn't belong anymore to the domain - after 2), the current domain already have a reference. Write will occur to an old page which is not yet released. It can corrupt the foreign domain. Signed-off-by: Julien Grall Acked-by: Ian Campbell --- Changes in v5: - Missing rcu_unlock_domain in one path - Check if the foreign page is RAM Changes in v4: - Typo s/release/released/ - Improve commit message Changes in v3: - Typoes - Check if the foreign domain is different from the current domain Changes in v2: - Even if gcc is buggy (see http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18501) define p2m type per mapspace to let the compiler warns about unitialized values. --- xen/arch/arm/mm.c | 38 ++++++++++++++++++++++++++++++-------- xen/include/asm-arm/p2m.h | 1 + 2 files changed, 31 insertions(+), 8 deletions(-) diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c index b1222be..6829822 100644 --- a/xen/arch/arm/mm.c +++ b/xen/arch/arm/mm.c @@ -977,6 +977,7 @@ static int xenmem_add_to_physmap_one( { unsigned long mfn = 0; int rc; + p2m_type_t t; switch ( space ) { @@ -1009,22 +1010,33 @@ static int xenmem_add_to_physmap_one( d->arch.grant_table_gpfn[idx] = gpfn; + t = p2m_ram_rw; + spin_unlock(&d->grant_table->lock); break; case XENMAPSPACE_shared_info: - if ( idx == 0 ) - mfn = virt_to_mfn(d->shared_info); - else + if ( idx != 0 ) return -EINVAL; + + mfn = virt_to_mfn(d->shared_info); + t = p2m_ram_rw; + break; case XENMAPSPACE_gmfn_foreign: { - paddr_t maddr; struct domain *od; + struct page_info *page; + p2m_type_t p2mt; od = rcu_lock_domain_by_any_id(foreign_domid); if ( od == NULL ) return -ESRCH; + if ( od == d ) + { + rcu_unlock_domain(od); + return -EINVAL; + } + rc = xsm_map_gmfn_foreign(XSM_TARGET, d, od); if ( rc ) { @@ -1032,15 +1044,25 @@ static int xenmem_add_to_physmap_one( return rc; } - maddr = p2m_lookup(od, pfn_to_paddr(idx), NULL); - if ( maddr == INVALID_PADDR ) + /* Take reference to the foreign domain page. + * Reference will be released in XENMEM_remove_from_physmap */ + page = get_page_from_gfn(od, idx, &p2mt, P2M_ALLOC); + if ( !page ) { dump_p2m_lookup(od, pfn_to_paddr(idx)); rcu_unlock_domain(od); return -EINVAL; } - mfn = maddr >> PAGE_SHIFT; + if ( !p2m_is_ram(p2mt) ) + { + put_page(page); + rcu_unlock_domain(od); + return -EINVAL; + } + + mfn = page_to_mfn(page); + t = p2m_map_foreign; rcu_unlock_domain(od); break; @@ -1051,7 +1073,7 @@ static int xenmem_add_to_physmap_one( } /* Map at new location. */ - rc = guest_physmap_add_page(d, gpfn, mfn, 0); + rc = guest_physmap_add_entry(d, gpfn, mfn, 0, t); return rc; } diff --git a/xen/include/asm-arm/p2m.h b/xen/include/asm-arm/p2m.h index ac2b6fa..6a185db 100644 --- a/xen/include/asm-arm/p2m.h +++ b/xen/include/asm-arm/p2m.h @@ -47,6 +47,7 @@ typedef enum { } p2m_type_t; #define p2m_is_foreign(_t) ((_t) == p2m_map_foreign) +#define p2m_is_ram(_t) ((_t) == p2m_ram_rw || (_t) == p2m_ram_ro) /* Initialise vmid allocator */ void p2m_vmid_allocator_init(void);