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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2F291C4332F for ; Thu, 10 Nov 2022 12:58:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229968AbiKJM6y (ORCPT ); Thu, 10 Nov 2022 07:58:54 -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 Content-Type: text/plain; charset=UTF-8 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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;