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 X-Spam-Level: X-Spam-Status: No, score=-9.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D9A4FC35247 for ; Tue, 4 Feb 2020 17:59:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B0D1122464 for ; Tue, 4 Feb 2020 17:59:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="cZvdvgC6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727526AbgBDR70 (ORCPT ); Tue, 4 Feb 2020 12:59:26 -0500 Received: from mail-pj1-f66.google.com ([209.85.216.66]:55935 "EHLO mail-pj1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727512AbgBDR7Z (ORCPT ); Tue, 4 Feb 2020 12:59:25 -0500 Received: by mail-pj1-f66.google.com with SMTP id d5so1706646pjz.5 for ; Tue, 04 Feb 2020 09:59:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=nfh22yuIBMeQ3kvIydY8ilzEcSZOCdGdBZ/eBSsIN/Q=; b=cZvdvgC6JY1X2WLdvXp4m3GQ+VLpqwAwdJRWr3OHt+mDbjcYTLQTWTP5LOy0VNI2J9 GsZ6G3+eROIlZRwhBOKiZei6C4Y24+XLK6CnTNAVCElkoqyA2ndnkIHuaKxR5/ropUFE xt/v49ir5Air6MKMQtxu4OQjBsAEyLuuoJ13Kqn2lLoqUsdLN06QPqAg6XtiWVju/5RL RNfC7XniMD6tlt3sN0WYRTWli2s1MXpEmWdYaM6cWc23RpF4AnDSJYjuDGMa7mr17ylN /cQ8tR7Ax4Ee2JmrlRO+Tu4hKx/Pb4zCeLXk+x3gUjQ26RcxPCXJDcDbRpqSqACDBw23 1igQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=nfh22yuIBMeQ3kvIydY8ilzEcSZOCdGdBZ/eBSsIN/Q=; b=CyHJ1/MAKeqIokz1AzXGuwNldmB028nfqRPtGoEjxNeipmr3apNQMBN4Sofo68XBeo LurvHwj+r3N35u0YQYTXrlOHvtTYo7LjTAIB7PnruSiz8xNB+3HfDEAM7s81ia2LP8Aa ZHfX0gE+skhezJa+9pIKxgon1syZGYF0US6mQAwNK++M6amFvGk9+f6kk4tmw9Eo1oBo tl9UCq/+AlG4ya8s5m2O7qskObW6Fx8K8//iPpdyrdIU9FV7/gkjiT5vVRzM2fx6cWX4 em5JtrW8inzllQ8VuAheG5RAujPsbf5PUQHNErqF99t0kPpWGbCkIIU7y/j/gmVZ+3Mv A7dQ== X-Gm-Message-State: APjAAAVzDpnItU7/Qwg5k9B0aiDbctKJH7aXwfvNmb48PAMRYBJ6ajsL C4fP6AxwWFyrB6N9Q/PsXp0= X-Google-Smtp-Source: APXvYqw9azuHvBSMLyzc/8cqmPByqTFaxmhbhNKiyzp8wI/JEy0MYOpijPSV6ICe+k2TNK2BwWVxAQ== X-Received: by 2002:a17:90a:9c1:: with SMTP id 59mr305035pjo.65.1580839164471; Tue, 04 Feb 2020 09:59:24 -0800 (PST) Received: from localhost.localdomain ([2620:0:1008:fd00:25a6:3140:768c:a64d]) by smtp.gmail.com with ESMTPSA id d73sm25414465pfd.109.2020.02.04.09.59.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 04 Feb 2020 09:59:23 -0800 (PST) From: Andrei Vagin To: Vincenzo Frascino Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Andrei Vagin , Thomas Gleixner , Dmitry Safonov Subject: [PATCH 1/5] arm64/vdso: use the fault callback to map vvar pages Date: Tue, 4 Feb 2020 09:59:09 -0800 Message-Id: <20200204175913.74901-2-avagin@gmail.com> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20200204175913.74901-1-avagin@gmail.com> References: <20200204175913.74901-1-avagin@gmail.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is required to support time namespaces where a time namespace data page is different for each namespace. Signed-off-by: Andrei Vagin --- arch/arm64/kernel/vdso.c | 26 +++++++++++++++++--------- 1 file changed, 17 insertions(+), 9 deletions(-) diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c index 354b11e27c07..c4b4758eaf0b 100644 --- a/arch/arm64/kernel/vdso.c +++ b/arch/arm64/kernel/vdso.c @@ -114,28 +114,32 @@ static int __vdso_init(enum arch_vdso_type arch_index) PAGE_SHIFT; /* Allocate the vDSO pagelist, plus a page for the data. */ - vdso_pagelist = kcalloc(vdso_lookup[arch_index].vdso_pages + 1, + vdso_pagelist = kcalloc(vdso_lookup[arch_index].vdso_pages, sizeof(struct page *), GFP_KERNEL); if (vdso_pagelist == NULL) return -ENOMEM; - /* Grab the vDSO data page. */ - vdso_pagelist[0] = phys_to_page(__pa_symbol(vdso_data)); - - /* Grab the vDSO code pages. */ pfn = sym_to_pfn(vdso_lookup[arch_index].vdso_code_start); for (i = 0; i < vdso_lookup[arch_index].vdso_pages; i++) - vdso_pagelist[i + 1] = pfn_to_page(pfn + i); + vdso_pagelist[i] = pfn_to_page(pfn + i); - vdso_lookup[arch_index].dm->pages = &vdso_pagelist[0]; - vdso_lookup[arch_index].cm->pages = &vdso_pagelist[1]; + vdso_lookup[arch_index].cm->pages = vdso_pagelist; return 0; } +static vm_fault_t vvar_fault(const struct vm_special_mapping *sm, + struct vm_area_struct *vma, struct vm_fault *vmf) +{ + if (vmf->pgoff == 0) + return vmf_insert_pfn(vma, vmf->address, + sym_to_pfn(vdso_data)); + return VM_FAULT_SIGBUS; +} + static int __setup_additional_pages(enum arch_vdso_type arch_index, struct mm_struct *mm, struct linux_binprm *bprm, @@ -155,7 +159,7 @@ static int __setup_additional_pages(enum arch_vdso_type arch_index, } ret = _install_special_mapping(mm, vdso_base, PAGE_SIZE, - VM_READ|VM_MAYREAD, + VM_READ|VM_MAYREAD|VM_PFNMAP, vdso_lookup[arch_index].dm); if (IS_ERR(ret)) goto up_fail; @@ -206,6 +210,8 @@ static int aarch32_vdso_mremap(const struct vm_special_mapping *sm, #define C_SIGPAGE 1 #define C_PAGES (C_SIGPAGE + 1) #endif /* CONFIG_COMPAT_VDSO */ +static vm_fault_t vvar_fault(const struct vm_special_mapping *sm, + struct vm_area_struct *vma, struct vm_fault *vmf); static struct page *aarch32_vdso_pages[C_PAGES] __ro_after_init; static struct vm_special_mapping aarch32_vdso_spec[C_PAGES] = { { @@ -215,6 +221,7 @@ static struct vm_special_mapping aarch32_vdso_spec[C_PAGES] = { #ifdef CONFIG_COMPAT_VDSO { .name = "[vvar]", + .fault = vvar_fault, }, { .name = "[vdso]", @@ -396,6 +403,7 @@ static int vdso_mremap(const struct vm_special_mapping *sm, static struct vm_special_mapping vdso_spec[A_PAGES] __ro_after_init = { { .name = "[vvar]", + .fault = vvar_fault, }, { .name = "[vdso]", -- 2.24.1