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[2620:137:e000::1:20]) by mx.google.com with ESMTP id t67-20020a635f46000000b004404705691dsi18929655pgb.487.2022.11.10.05.01.40; Thu, 10 Nov 2022 05:02:10 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@infradead.org header.s=desiato.20200630 header.b="aao/1O51"; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230032AbiKJM66 (ORCPT + 99 others); Thu, 10 Nov 2022 07:58:58 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54402 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229710AbiKJM6p (ORCPT ); Thu, 10 Nov 2022 07:58:45 -0500 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5219C70198 for ; Thu, 10 Nov 2022 04:58:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Content-Type:MIME-Version:References: Subject:Cc:To:From:Date:Message-ID:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:In-Reply-To; bh=69SLcLIsDhF1CjVYnMtPLtLafQoTPWsbqqCXMi0foHc=; b=aao/1O515RcVd5zFc8nqYMfrBm vkQICFFzeHIiyP07SS06G1lP1QBXibO5T22nVRwTUeqb0smoTQpVVnm7jPQAtQpg9sP7bq6GV7eRk aJvID8I0FeRTadexQ77fpyV9sQ1Ct4Ch2QdU+WtwGwZtOTm6cE3jMA97f1vsLWpLbDXSRMJyuDVHW m0ifOp6g2hNYyBiza4dEgVWswZog3e0Bv6oKlSU87KGLp6dLIi5wDv9Np5Q7HpujZQeRvPx9gD7GR oYK5VfU4qVAgetSlXlsHUqx4VFCnBtoG6y9V212KuhNczE/KjGra5KPotuIerwHX/IRhCU8Dd+iWc eqXPBKMQ==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1ot78X-00AHCe-A2; Thu, 10 Nov 2022 12:58:30 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id CAC7B30041D; Thu, 10 Nov 2022 13:58:27 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id A22C32B97261E; Thu, 10 Nov 2022 13:58:27 +0100 (CET) Message-ID: <20221110125544.460677011@infradead.org> User-Agent: quilt/0.66 Date: Thu, 10 Nov 2022 13:52:54 +0100 From: Peter Zijlstra To: x86@kernel.org, dave.hansen@intel.com Cc: linux-kernel@vger.kernel.org, peterz@infradead.org, torvalds@linux-foundation.org, oliver.sang@intel.com Subject: [PATCH 1/4] x86/mm: Add a few comments References: <20221110125253.240704966@infradead.org> MIME-Version: 1.0 X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_MED,SPF_HELO_NONE, SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1749114243955292417?= X-GMAIL-MSGID: =?utf-8?q?1749114243955292417?= It's a shame to hide useful comments in Changelogs, add some to the code. Shamelessly stolen from commit: c40a56a7818c ("x86/mm/init: Remove freed kernel image areas from alias mapping") Signed-off-by: Peter Zijlstra (Intel) --- arch/x86/mm/pat/set_memory.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) --- a/arch/x86/mm/pat/set_memory.c +++ b/arch/x86/mm/pat/set_memory.c @@ -219,6 +219,17 @@ within_inclusive(unsigned long addr, uns #ifdef CONFIG_X86_64 +/* + * The kernel image is mapped into two places in the virtual address space + * (addresses without KASLR, of course): + * + * 1. The kernel direct map (0xffff880000000000) + * 2. The "high kernel map" (0xffffffff81000000) + * + * We actually execute out of #2. If we get the address of a kernel symbol, it + * points to #2, but almost all physical-to-virtual translations point to #1. + */ + static inline unsigned long highmap_start_pfn(void) { return __pa_symbol(_text) >> PAGE_SHIFT; @@ -1626,6 +1637,9 @@ static int __change_page_attr(struct cpa static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias); +/* + * Check the directmap and "high kernel map" 'aliases'. + */ static int cpa_process_alias(struct cpa_data *cpa) { struct cpa_data alias_cpa; From patchwork Thu Nov 10 12:52:55 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Zijlstra X-Patchwork-Id: 18117 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a5d:6687:0:0:0:0:0 with SMTP id l7csp131876wru; Thu, 10 Nov 2022 05:01:45 -0800 (PST) X-Google-Smtp-Source: AMsMyM74ubL90NMCoWEcH1CvUSjQPB3ZLTBugpuZgurHHVWC3sKgmb0qKLHlMxmgTEYtFJ+YhmIV X-Received: by 2002:a17:906:db0e:b0:77b:82cf:54a6 with SMTP id xj14-20020a170906db0e00b0077b82cf54a6mr58685674ejb.691.1668085305742; Thu, 10 Nov 2022 05:01:45 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1668085305; cv=none; d=google.com; s=arc-20160816; b=o//N2jmphAnYiaoLSDFNQG48cZ8Q3t3aqhS/3xK+ikeidx/lkU2kz5y23XgmrsAXnK W7rnJiPdlnv1zaG1fqmF1SXi6IpdnSh8xjXWpI7rjzwSoTUlKfqYNNVa37Tt0c+Uf4ty MRBp1utXTJoGfbefAER1TIPu92SG1yhrPAXQ9GVMCvmdGN7DqiQ4JkVTkUDIK18iIF4X W2kgrIy4kegPDaU44AzTwOjV9S27wRoYk4zb3E6IP0V+eVfiD0rmmU/JcRyu+NYAXQfs Evx61dd+OGZXmoGg2AJ3S1ZQrZCpBvL5kaEpPXSQJbPef3S23IV6kPU523URrmBlJ0kn gRhA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:mime-version:references:subject:cc:to:from:date :user-agent:message-id:dkim-signature; bh=fK9e3H2vvSo4YD2UMwim5ynsXg6YjBcd0FJLh46S8ZE=; b=b1I063Y/IPIBEvhetPpKxCmV1O1QOnjROREeRgbcmMI+DScZNpKHvE0kHZoKYhpdLh Ie8cFDZsJCIWPynNHVy54Somt3d7izAVkdkZuiFe1pUrzp7BuJqse9y7Vnt6zNV2daM6 WzMocgjFmUD4pndR9veBP37qkWxr7sF7mDpAZ7/ACwRiRECZgORCWgwzrbdO61bD43j7 5jLKzBlQ3mES3plA29+OY0nDzskOxsCa3vPNZ8BWIrKztDXcyy0xo6Hc1km54G7TFrsD TcQsN7AOIqBnB7K4NRgTd7eoRRddRhyiMHh5XP1N9oo/z4qms8srMGEZqTxdehpCqyXh nP2g== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@infradead.org header.s=desiato.20200630 header.b=V36svHFu; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id cs5-20020a0564020c4500b00463f8aad371si17742166edb.239.2022.11.10.05.01.12; Thu, 10 Nov 2022 05:01:45 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@infradead.org header.s=desiato.20200630 header.b=V36svHFu; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229957AbiKJM6x (ORCPT + 99 others); Thu, 10 Nov 2022 07:58:53 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54400 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229649AbiKJM6p (ORCPT ); Thu, 10 Nov 2022 07:58:45 -0500 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1DE5B70192 for ; Thu, 10 Nov 2022 04:58:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Content-Type:MIME-Version:References: Subject:Cc:To:From:Date:Message-ID:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:In-Reply-To; bh=fK9e3H2vvSo4YD2UMwim5ynsXg6YjBcd0FJLh46S8ZE=; b=V36svHFuawhbJZoUBai89Jf8Tv CFKRKQKvE4eRIkh+tbevxX60TvNpowHCphz2U9NnQdYocNofptdwB2r0dCca1VLKpZS2uck02NOeP j2YRIpujpv82ScV+V+jhaKoZ37JECkNup5yK0wtzNoSwfqrvxviiiShTm5ed7RjOmFKQqCrn8C1QI GarWOmJQ6q5xXabemmbbEzU2sGRHccoOB4OSXDxW2KklKXhINPq7TIbrblXzy2clpufwlIB+hPiRV gswHXEBbbqZSnPlRZZ7ozQ2fa9ASBL7dhmKi2hs9ZiCrrttcmSBIorHDPkV644UiHN6JnIqNJiIgR TN2g0sYg==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1ot78X-00AHCh-9x; Thu, 10 Nov 2022 12:58:30 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id C8FB130036B; Thu, 10 Nov 2022 13:58:27 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id A45B4205A765D; Thu, 10 Nov 2022 13:58:27 +0100 (CET) Message-ID: <20221110125544.527267183@infradead.org> User-Agent: quilt/0.66 Date: Thu, 10 Nov 2022 13:52:55 +0100 From: Peter Zijlstra To: x86@kernel.org, dave.hansen@intel.com Cc: linux-kernel@vger.kernel.org, peterz@infradead.org, torvalds@linux-foundation.org, oliver.sang@intel.com Subject: [PATCH 2/4] x86/mm: Untangle __change_page_attr_set_clr(.checkalias) References: <20221110125253.240704966@infradead.org> MIME-Version: 1.0 X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_MED,SPF_HELO_NONE, SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1749114217187991607?= X-GMAIL-MSGID: =?utf-8?q?1749114217187991607?= The .checkalias argument to __change_page_attr_set_clr() is overloaded and serves two different purposes: - it inhibits the call to cpa_process_alias() -- as suggested by the name; however, - it also serves as 'primary' indicator for __change_page_attr() ( which in turn also serves as a recursion terminator for cpa_process_alias() ). Untangle these by extending the use of CPA_NO_CHECK_ALIAS to all callsites that currently use .checkalias=0 for this purpose. Signed-off-by: Peter Zijlstra (Intel) --- arch/x86/mm/pat/set_memory.c | 30 +++++++++++------------------- 1 file changed, 11 insertions(+), 19 deletions(-) --- a/arch/x86/mm/pat/set_memory.c +++ b/arch/x86/mm/pat/set_memory.c @@ -1721,7 +1721,7 @@ static int __change_page_attr_set_clr(st if (ret) goto out; - if (checkalias) { + if (checkalias && !(cpa->flags & CPA_NO_CHECK_ALIAS)) { ret = cpa_process_alias(cpa); if (ret) goto out; @@ -1795,18 +1795,12 @@ static int change_page_attr_set_clr(unsi cpa.numpages = numpages; cpa.mask_set = mask_set; cpa.mask_clr = mask_clr; - cpa.flags = 0; + cpa.flags = in_flag; cpa.curpage = 0; cpa.force_split = force_split; - if (in_flag & (CPA_ARRAY | CPA_PAGES_ARRAY)) - cpa.flags |= in_flag; - /* No alias checking for _NX bit modifications */ checkalias = (pgprot_val(mask_set) | pgprot_val(mask_clr)) != _PAGE_NX; - /* Has caller explicitly disabled alias checking? */ - if (in_flag & CPA_NO_CHECK_ALIAS) - checkalias = 0; ret = __change_page_attr_set_clr(&cpa, checkalias); @@ -2061,11 +2055,9 @@ int set_memory_np(unsigned long addr, in int set_memory_np_noalias(unsigned long addr, int numpages) { - int cpa_flags = CPA_NO_CHECK_ALIAS; - return change_page_attr_set_clr(&addr, numpages, __pgprot(0), __pgprot(_PAGE_PRESENT), 0, - cpa_flags, NULL); + CPA_NO_CHECK_ALIAS, NULL); } int set_memory_4k(unsigned long addr, int numpages) @@ -2282,7 +2274,7 @@ static int __set_pages_p(struct page *pa .numpages = numpages, .mask_set = __pgprot(_PAGE_PRESENT | _PAGE_RW), .mask_clr = __pgprot(0), - .flags = 0}; + .flags = CPA_NO_CHECK_ALIAS }; /* * No alias checking needed for setting present flag. otherwise, @@ -2290,7 +2282,7 @@ static int __set_pages_p(struct page *pa * mappings (this adds to complexity if we want to do this from * atomic context especially). Let's keep it simple! */ - return __change_page_attr_set_clr(&cpa, 0); + return __change_page_attr_set_clr(&cpa, 1); } static int __set_pages_np(struct page *page, int numpages) @@ -2301,7 +2293,7 @@ static int __set_pages_np(struct page *p .numpages = numpages, .mask_set = __pgprot(0), .mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW), - .flags = 0}; + .flags = CPA_NO_CHECK_ALIAS }; /* * No alias checking needed for setting not present flag. otherwise, @@ -2309,7 +2301,7 @@ static int __set_pages_np(struct page *p * mappings (this adds to complexity if we want to do this from * atomic context especially). Let's keep it simple! */ - return __change_page_attr_set_clr(&cpa, 0); + return __change_page_attr_set_clr(&cpa, 1); } int set_direct_map_invalid_noflush(struct page *page) @@ -2380,7 +2372,7 @@ int __init kernel_map_pages_in_pgd(pgd_t .numpages = numpages, .mask_set = __pgprot(0), .mask_clr = __pgprot(~page_flags & (_PAGE_NX|_PAGE_RW)), - .flags = 0, + .flags = CPA_NO_CHECK_ALIAS, }; WARN_ONCE(num_online_cpus() > 1, "Don't call after initializing SMP"); @@ -2393,7 +2385,7 @@ int __init kernel_map_pages_in_pgd(pgd_t cpa.mask_set = __pgprot(_PAGE_PRESENT | page_flags); - retval = __change_page_attr_set_clr(&cpa, 0); + retval = __change_page_attr_set_clr(&cpa, 1); __flush_tlb_all(); out: @@ -2423,12 +2415,12 @@ int __init kernel_unmap_pages_in_pgd(pgd .numpages = numpages, .mask_set = __pgprot(0), .mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW), - .flags = 0, + .flags = CPA_NO_CHECK_ALIAS, }; WARN_ONCE(num_online_cpus() > 1, "Don't call after initializing SMP"); - retval = __change_page_attr_set_clr(&cpa, 0); + retval = __change_page_attr_set_clr(&cpa, 1); __flush_tlb_all(); return retval; From patchwork Thu Nov 10 12:52:56 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Zijlstra X-Patchwork-Id: 18116 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a5d:6687:0:0:0:0:0 with SMTP id l7csp131632wru; Thu, 10 Nov 2022 05:01:28 -0800 (PST) X-Google-Smtp-Source: AA0mqf5JuYhy6zT27BkPlQv3ESqm1ArUl7JC7d0YX0OM250T/zz0O1zLM8ZJaFV2wFB2BVMYrfya X-Received: by 2002:a17:906:3c1:b0:7ae:6e4b:6c06 with SMTP id c1-20020a17090603c100b007ae6e4b6c06mr15060745eja.70.1668085288667; Thu, 10 Nov 2022 05:01:28 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1668085288; cv=none; d=google.com; s=arc-20160816; b=yKq6Ca431fGQOdGNGsZj1BKtsTzsDsVOtFy4X4FJLqtAkssc4QZYhDvgPBn6c07cVH bvE9KFj5dAV5IMgqBFMcKIPdOl9vjuk0jdROWZH/sM6LAOx4hQFg8UbVncCHbV4xvbCj gVg1aftaXVxJQl2LxH1Caxm7KHN+fiHf5fDayzchX2YOYxtJ5zXJM1A+Ly9HLO2uhjp3 x0fxuOkB9d6kyw6qzCk1djW3sP6POJ7DiI63PKQc/YOdoTKonSxdBIprY/gvYvYIX19t P1x40DHY3Tt5nRs2zVbD+RARiAgjvA2+sH6HbQTeeo4WQ6D/NXfaHEDSJL91Vl4r4P8F AJzw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:mime-version:references:subject:cc:to:from:date :user-agent:message-id:dkim-signature; bh=aPpH2DkMTrxhIpV4/nr31HwzcYRECeuZHF/THcTg9IQ=; b=wA251GQhjZEPnV8xtsVgVFcXsw5Btkv07rdx+BXasA8Q+HI4hLvnYtvcUTTp2hGoTV oUovr+2AagUIWbvxBkzxP5J4f59TuI/d6YQS9g7O1VOtqqsXpWCGeQGbPcO1HCiVu0po 02oORI1oV54RgVVOpXLYt5tGyAJAqTLQlY5eNoMquOAnW+AmCGKtJKCZ48Ssc7827UVN 7DS+Z9hamLIp+nUxHXpg4d/bP2BAXi1WoOHRgz7653Za/XKOKgWNuSE208sVK79qgSom zi9Ja5r/kpsxpJtpwsTrGcGtTj7zbzwxL409DauIkBteYim0RyGfzZhMdcJRMlMk7ja6 6kGQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@infradead.org header.s=desiato.20200630 header.b=bOrHaMwg; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: from out1.vger.email (out1.vger.email. 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The introduction of set_memory_rox() triggered this last issue for clearing both _PAGE_RW and _PAGE_NX. Explicitly ignore _PAGE_NX in cpa_process_alias() instead. Fixes: b38994948567 ("x86/mm: Implement native set_memory_rox()") Reported-by: kernel test robot Debugged-by: Dave Hansen Signed-off-by: Peter Zijlstra (Intel) Acked-by: Dave Hansen --- arch/x86/mm/pat/set_memory.c | 28 +++++++++++++++++++++++----- 1 file changed, 23 insertions(+), 5 deletions(-) --- a/arch/x86/mm/pat/set_memory.c +++ b/arch/x86/mm/pat/set_memory.c @@ -1663,6 +1663,12 @@ static int cpa_process_alias(struct cpa_ alias_cpa.flags &= ~(CPA_PAGES_ARRAY | CPA_ARRAY); alias_cpa.curpage = 0; + /* Directmap always has NX set, do not modify. */ + if (__supported_pte_mask & _PAGE_NX) { + alias_cpa.mask_clr.pgprot &= ~_PAGE_NX; + alias_cpa.mask_set.pgprot &= ~_PAGE_NX; + } + cpa->force_flush_all = 1; ret = __change_page_attr_set_clr(&alias_cpa, 0); @@ -1685,6 +1691,15 @@ static int cpa_process_alias(struct cpa_ alias_cpa.flags &= ~(CPA_PAGES_ARRAY | CPA_ARRAY); alias_cpa.curpage = 0; + /* + * [_text, _brk_end) also covers data, do not modify NX except + * in cases where the highmap is the primary target. + */ + if (__supported_pte_mask & _PAGE_NX) { + alias_cpa.mask_clr.pgprot &= ~_PAGE_NX; + alias_cpa.mask_set.pgprot &= ~_PAGE_NX; + } + cpa->force_flush_all = 1; /* * The high mapping range is imprecise, so ignore the @@ -1703,6 +1718,12 @@ static int __change_page_attr_set_clr(st unsigned long rempages = numpages; int ret = 0; + /* + * No changes, easy! + */ + if (!(pgprot_val(cpa->mask_set) | pgprot_val(cpa->mask_clr))) + return ret; + while (rempages) { /* * Store the remaining nr of pages for the large page @@ -1749,7 +1770,7 @@ static int change_page_attr_set_clr(unsi struct page **pages) { struct cpa_data cpa; - int ret, cache, checkalias; + int ret, cache; memset(&cpa, 0, sizeof(cpa)); @@ -1799,10 +1820,7 @@ static int change_page_attr_set_clr(unsi cpa.curpage = 0; cpa.force_split = force_split; - /* No alias checking for _NX bit modifications */ - checkalias = (pgprot_val(mask_set) | pgprot_val(mask_clr)) != _PAGE_NX; - - ret = __change_page_attr_set_clr(&cpa, checkalias); + ret = __change_page_attr_set_clr(&cpa, 1); /* * Check whether we really changed something: From patchwork Thu Nov 10 12:52:57 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Zijlstra X-Patchwork-Id: 18118 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a5d:6687:0:0:0:0:0 with SMTP id l7csp132044wru; Thu, 10 Nov 2022 05:01:57 -0800 (PST) X-Google-Smtp-Source: AMsMyM4kG9FkhAnvklmGz6WSE7TLVUASRBIpqiUIksrQEZj7m0kuA+dRP6xAhHf7XTditK9srdnh X-Received: by 2002:a17:906:4898:b0:78d:4935:1ad8 with SMTP id v24-20020a170906489800b0078d49351ad8mr2706635ejq.564.1668085317643; Thu, 10 Nov 2022 05:01:57 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1668085317; cv=none; d=google.com; s=arc-20160816; b=nQTdi7QEMhF1zM49s11PrARKKoBOJSIbjvpEEegM8bGKR5b/9aQ9lTnkvKOXioMKmE YUTiH+QZJlSD2lc0SQqNaq4XYweOVftRw6Yt/+Imi1u2QFFGBdgblWt/iACjkniC8UWa IukjpUgidw+AbRLLKvSdS0uBA+mneq2BdWcxE4BqfXfKewWXR2FEWe44UvN8BmagPrVt v5Ws4+mlv3RLvf3mRe/NNTDa4vcWSuRgm1RPG6k830eypDflFfTlQPr15oGHhQFleI3x /oiN867whRwW7wwoA3WOs51UVf4LQivVzcwluhdmfERzSLKZsHWspv2/G80qGXFYF0ya Ca0A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:mime-version:references:subject:cc:to:from:date :user-agent:message-id:dkim-signature; bh=0TJ9GM3QmpQqqobwlFgaZAhiMEzovhIsHgiWH55IfFY=; b=Ux5pxAm8P4ahlLjS1u+m/Fp7N2QLIz4xmYGhIcC7s4mHJpDra/ZOOvgSNPSgChc2bV yAyPsHrgzDlTtuimbv0JuhlldxLDFy9MC/XvJEi0y5vDocJxxTe/XACuoj0G0EEwZSsN OchIPkjY8MfisA1Cn12khnGYPKB5e2Z/nSyY7WJgqXeJ2GnKXN8rJ0mpVER2udY4Yyxa 6Ut9pJjAReHAkm2ShcNFf0uj3+Q+AkvU0n5kWDkScZ9aF+Qh8jB4+ErzpPGSK30J80+p L5lqc0oAIza1HTdsMq//TXW7FKpaxfOyYWo5HsraOeE9TAbinqmNTxLLUNk8vjCTb/5g VJhw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@infradead.org header.s=desiato.20200630 header.b=XVvw5AjH; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: from out1.vger.email (out1.vger.email. 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Signed-off-by: Peter Zijlstra (Intel) --- arch/x86/mm/pat/set_memory.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/arch/x86/mm/pat/set_memory.c +++ b/arch/x86/mm/pat/set_memory.c @@ -1635,7 +1635,7 @@ static int __change_page_attr(struct cpa return err; } -static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias); +static int __change_page_attr_set_clr(struct cpa_data *cpa, int primary); /* * Check the directmap and "high kernel map" 'aliases'. @@ -1712,7 +1712,7 @@ static int cpa_process_alias(struct cpa_ return 0; } -static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias) +static int __change_page_attr_set_clr(struct cpa_data *cpa, int primary) { unsigned long numpages = cpa->numpages; unsigned long rempages = numpages; @@ -1736,13 +1736,13 @@ static int __change_page_attr_set_clr(st if (!debug_pagealloc_enabled()) spin_lock(&cpa_lock); - ret = __change_page_attr(cpa, checkalias); + ret = __change_page_attr(cpa, primary); if (!debug_pagealloc_enabled()) spin_unlock(&cpa_lock); if (ret) goto out; - if (checkalias && !(cpa->flags & CPA_NO_CHECK_ALIAS)) { + if (primary && !(cpa->flags & CPA_NO_CHECK_ALIAS)) { ret = cpa_process_alias(cpa); if (ret) goto out;