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,URIBL_BLOCKED,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 32576C433E0 for ; Tue, 2 Jun 2020 18:03:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0CCF82074B for ; Tue, 2 Jun 2020 18:03:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="VuUGPGEo" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727924AbgFBSDO (ORCPT ); Tue, 2 Jun 2020 14:03:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35874 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726139AbgFBSDG (ORCPT ); Tue, 2 Jun 2020 14:03:06 -0400 Received: from mail-pg1-x542.google.com (mail-pg1-x542.google.com [IPv6:2607:f8b0:4864:20::542]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 207F5C05BD1E for ; Tue, 2 Jun 2020 11:03:06 -0700 (PDT) Received: by mail-pg1-x542.google.com with SMTP id p21so5434928pgm.13 for ; Tue, 02 Jun 2020 11:03:06 -0700 (PDT) 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=QGD1nesqWyjyIgD1rTMvSAFAGLyEEfpYf/1KB187E2U=; b=VuUGPGEoUPTURf3RYtx8Z5AxOLk+4ls2cqG0NCwDdNNrLuavo7E/67YQMT5DYSBitj DcxdX+4jvlaoTt9LHsCu9HGbMyZHqQ6bVCSFaB8adeIRJm4fYzmR31+I5r3RCSP+amp9 Pk9bR/KKzgVT3IRovnElkSO1N87zEp8wXAQZNx1nk54spjwa7E50kcADlKGaec7JO5BU 2ltsrKE+wN67Y4f+JCgLF3gJ8QtqQfDUZNJSqnZvmO+DgSRj/YF6/iyS8GIczHHE0RJj ZFCYC0aiCiiKNi5M5a43bEI7CwXFp6IEhnQlUwkt7XtDd9GX3rQhMsJer4wWS70asgJA iANw== 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=QGD1nesqWyjyIgD1rTMvSAFAGLyEEfpYf/1KB187E2U=; b=ia643B6+kmRBkX0DmUjusu1B7z9S4QPCO4aDtAo15MrkJTe/bpJZ+E9V8KTgEbcHTg B9mteyDMfUvAIUcYW8v2GV7BQgX2XgGIC//NsTJp015MMvPUTshOe0mjdHvPVfFoStpv wsTqqvaxCx0oUn9ZPwlIQypTrgCgftKy57Ks5un7XnehrzSYvaC1fiO8a1ce0jrpTYpM 8zpaO2AC5jXLzvNR196S6ElypWl/XI8DMkJH+OdwyE3NiYcz0vN+Y/JDP4wZQ8Qbgi5R IwjqQOr1MFW6T77UUBufIO0cmGLuKtYYME/zjAK6o5ri/+aPozezOqndAww24tyr8m1o 1uNw== X-Gm-Message-State: AOAM531xVJaFHsM++JMsbu+ifzWJjiPxq575xSSk5fUx/0k/kScF1rL6 MxdS8Iw7fcXRLSuT6g9+AgY= X-Google-Smtp-Source: ABdhPJxi9crDyNOlXl/+7uBWebXj2rltTHVnLx2F894AlFvwI/cNoCm8+fb6Ps/1YNhITdbvtnMY9Q== X-Received: by 2002:a63:e549:: with SMTP id z9mr26130165pgj.213.1591120985545; Tue, 02 Jun 2020 11:03:05 -0700 (PDT) Received: from laptop.hsd1.wa.comcast.net ([2601:600:817f:a132:df3e:521d:99d5:710d]) by smtp.gmail.com with ESMTPSA id p8sm2740053pgs.29.2020.06.02.11.03.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 02 Jun 2020 11:03:04 -0700 (PDT) From: Andrei Vagin To: linux-arm-kernel@lists.infradead.org, Catalin Marinas , Will Deacon Cc: linux-kernel@vger.kernel.org, Vincenzo Frascino , Mark Rutland , Thomas Gleixner , Dmitry Safonov , Andrei Vagin Subject: [PATCH 1/6] arm64/vdso: use the fault callback to map vvar pages Date: Tue, 2 Jun 2020 11:02:54 -0700 Message-Id: <20200602180259.76361-2-avagin@gmail.com> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20200602180259.76361-1-avagin@gmail.com> References: <20200602180259.76361-1-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. Reviewed-by: Vincenzo Frascino Signed-off-by: Andrei Vagin --- arch/arm64/kernel/vdso.c | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-) diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c index 033a48f30dbb..031ee1a8d4a8 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; @@ -215,6 +219,7 @@ static struct vm_special_mapping aarch32_vdso_spec[C_PAGES] = { #ifdef CONFIG_COMPAT_VDSO { .name = "[vvar]", + .fault = vvar_fault, }, { .name = "[vdso]", @@ -385,6 +390,7 @@ 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