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 9877AC4332F for ; Thu, 10 Nov 2022 11:36:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230268AbiKJLf7 (ORCPT ); Thu, 10 Nov 2022 06:35:59 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43564 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229870AbiKJLf4 (ORCPT ); Thu, 10 Nov 2022 06:35:56 -0500 Received: from mail-ej1-x64a.google.com (mail-ej1-x64a.google.com [IPv6:2a00:1450:4864:20::64a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 811FD657CD for ; Thu, 10 Nov 2022 03:35:55 -0800 (PST) Received: by mail-ej1-x64a.google.com with SMTP id sc40-20020a1709078a2800b007ae024e5e82so1031476ejc.13 for ; Thu, 10 Nov 2022 03:35:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=jpQdIr8MN/KQIwACigO7iQHcDhsbP3Ee3zIRpQPEK1o=; b=BdS5DojXBcJ/OgCf0l8c6arc3q1OeaTAXv3Uy1ty5TVvDwC0HX7pEDsrLLPvPBxy8Q 6tiW59sC/5j+SR3TzXGB6Pgz9sQpaerOtslUi/ofYKiyqHZX7/b16DDBPR0g2zkPft1I gKxPQedEpYMCI6GODG0p718Pxs2BoIyzTBXMH96j23FpxFb6jIIjU6dZLx7KkfiLh7ZK AG0CDGs67AgDIodUuACO2cWPs/CvG/y2GQHpf7is6flgF1JyWN9MCctmL/JOMnqI/fzh htO6DEwe7xL4MmovUHgjG9Mvaup+R3yyVzhif4Dt4g3OKhJNf/BiKZrLDPkYhhFA0DjN zeQg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=jpQdIr8MN/KQIwACigO7iQHcDhsbP3Ee3zIRpQPEK1o=; b=D9w0o7/kTNHrL6UrrJKLkAaDWsh1Hv8wZeQO0etnB8PFANvVCwGkMupD96QWw6GsHp H7FMA6pccd8Md5rWQwVYULVdn2m6LCFOiWfWaohLMpL++KExJ5NOJkoFlA1xYNfjNqTM jFKefILec34EZEzrS9UXCpIyNzdkw+wAirbNBE4vDqbX0X98wv5JPXAANsOySrUdvjyb VCo9++96NEQuZCliiDtzaIQ9oBMSEL4GEUli2abPBGTw/9UJqkazd7rA/Bb3y4Mqe0bF G9p3jkP+mrJwOIwUwU5HTX0wqqLjzKnnX/xLSa7txpxdSgLKHosS+mExMGJHGCVllxsw uhWw== X-Gm-Message-State: ACrzQf2Day2Yq72EkMuNVdMvvg0BHgccyulLPuAZexZi1qQ2H2hFqN9Z BJlvK5mQATmnHOTv8jg2YFYaC90dYy4= X-Google-Smtp-Source: AMsMyM5Wpq2hYUAuqWz1ozYNLgSCBs+6jjnjdfEkyB5OqXM4JKPfTlL3B70CVuNWA/k5s1z6YFE8U8wsLKw= X-Received: from glider.muc.corp.google.com ([2a00:79e0:9c:201:4f3e:16fb:f499:bb9d]) (user=glider job=sendgmr) by 2002:aa7:ccd2:0:b0:462:73bd:3acb with SMTP id y18-20020aa7ccd2000000b0046273bd3acbmr62699894edt.378.1668080154037; Thu, 10 Nov 2022 03:35:54 -0800 (PST) Date: Thu, 10 Nov 2022 12:35:41 +0100 Mime-Version: 1.0 X-Mailer: git-send-email 2.38.1.431.g37b22c650d-goog Message-ID: <20221110113541.1844156-1-glider@google.com> Subject: [PATCH] Revert "kmsan: unpoison @tlb in arch_tlb_gather_mmu()" From: Alexander Potapenko To: glider@google.com Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andrew Morton , Dmitry Vyukov , Eric Biggers , Linus Torvalds , Marco Elver , Peter Zijlstra , Will Deacon Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This reverts commit ac801e7e252c5588325e3c983c7d4167fc68c024. The patch in question was picked to -mm from the KMSAN v6 patch series (https://lore.kernel.org/linux-mm/20220905122452.2258262-1-glider@google.com/) and sneaked into mainline despite its removal from the v7 series (https://lore.kernel.org/linux-mm/20220915150417.722975-1-glider@google.com/) Currently KMSAN does not warn about origin chains hitting the maximum depth, so keeping @tlb poisoned won't result in any inconveniences. Cc: Andrew Morton Cc: Dmitry Vyukov Cc: Eric Biggers Cc: Linus Torvalds Cc: Marco Elver Cc: Peter Zijlstra (Intel) Cc: Will Deacon Signed-off-by: Alexander Potapenko --- mm/mmu_gather.c | 10 ---------- 1 file changed, 10 deletions(-) diff --git a/mm/mmu_gather.c b/mm/mmu_gather.c index add4244e5790d..a71924bd38c0d 100644 --- a/mm/mmu_gather.c +++ b/mm/mmu_gather.c @@ -1,7 +1,6 @@ #include #include #include -#include #include #include #include @@ -266,15 +265,6 @@ void tlb_flush_mmu(struct mmu_gather *tlb) static void __tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm, bool fullmm) { - /* - * struct mmu_gather contains 7 1-bit fields packed into a 32-bit - * unsigned int value. The remaining 25 bits remain uninitialized - * and are never used, but KMSAN updates the origin for them in - * zap_pXX_range() in mm/memory.c, thus creating very long origin - * chains. This is technically correct, but consumes too much memory. - * Unpoisoning the whole structure will prevent creating such chains. - */ - kmsan_unpoison_memory(tlb, sizeof(*tlb)); tlb->mm = mm; tlb->fullmm = fullmm; -- 2.38.1.431.g37b22c650d-goog