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=-23.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_IN_DEF_DKIM_WL 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 B4877C4338F for ; Thu, 29 Jul 2021 14:00:00 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 0075960FD7 for ; Thu, 29 Jul 2021 13:59:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 0075960FD7 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 4DEA38D0002; Thu, 29 Jul 2021 09:59:59 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 440CA8D0001; Thu, 29 Jul 2021 09:59:59 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2E07A8D0002; Thu, 29 Jul 2021 09:59:59 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0195.hostedemail.com [216.40.44.195]) by kanga.kvack.org (Postfix) with ESMTP id 0FD0F8D0001 for ; Thu, 29 Jul 2021 09:59:59 -0400 (EDT) Received: from smtpin14.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id B8E1A182C37EC for ; Thu, 29 Jul 2021 13:59:58 +0000 (UTC) X-FDA: 78415784076.14.D36D8F8 Received: from mail-qk1-f177.google.com (mail-qk1-f177.google.com [209.85.222.177]) by imf19.hostedemail.com (Postfix) with ESMTP id 730C2B0000A7 for ; Thu, 29 Jul 2021 13:59:58 +0000 (UTC) Received: by mail-qk1-f177.google.com with SMTP id c18so6030727qke.2 for ; Thu, 29 Jul 2021 06:59:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=KUvzSeTHiMYYDqDJxB7rJ4PNsknIyxmHg+DiEVHfwLI=; b=iOwiVk+59SLzINH9AVvJnCRQz3piAW2z7tpru53kHm1k8PiIusFJtd0SQ4xDI4FFc3 bZRCI6YMKhRT2u+U7GBQrmyv91J8yRGOkgseXRyYp7xA0e9h6yRbXixo5JdSxDfEAs4W sPxNOOwyfZFAAikVc79dsioyppviL3Wil4CQGo+DfLT7Ue0Gg4uRNRiJvoVSesolCxYI r/ec+r0NELHo0Yq/AxQB2kqG6MJ2iDFiU4M6evSHPfKc/MiE8MpoaypA8dItdSXeMmzY m1RgqdrArXNTrH/8k9p75lPGfzFckmisE2hIDyzz9R9qUOJcypGIT0WoDmlU3RJ+PCvi xp8g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=KUvzSeTHiMYYDqDJxB7rJ4PNsknIyxmHg+DiEVHfwLI=; b=MVVj07KcEzHN179GA9+hGvnMiXSj6+NHcWhFRMLeVbqQOkBCn58cQASanuaXzoIV4H /asLoAQFEX8kN8sFdfuNDvr2N3mq8N8dMt3Y9zUwAdJBLy2o0N3uGc2BheeACFlwk6BQ apcGGp4+8O/ngcNXR0K43E1tHrIykG9gv5mVtIQQK4/5Cc8kWyLbG4T+VMv8E8lN785Y uPzFlpggZAF6R5zWcO+5lTeq+pfBR6gRMGXDPqQF/2t4z/btIMXp+Njhfr1O2JXTUMJh tV7Yfm36Ja9Dzobvboc7tAC91WbOMdzxPUBHzgCj2pAJqiYy23hU3yGBrvks+U8TxgtB Cnrg== X-Gm-Message-State: AOAM533wgHjKfhAPFma34xC8J1OfJDXLHKENQuhEH/SWgvPe8sNNN/36 RSNkjpaf/gg+cTRLvnvp/t/UKl6+Bfs1wmdAui3z9g== X-Google-Smtp-Source: ABdhPJxSrKNbOK3NA1s7QIBVfkGMkfAw4PxjPNutIFyYV824DbkgAHKPEK0RIiQ0e7hLN3J7hdZ8bMltngwlkwTbnFk= X-Received: by 2002:a37:a5ca:: with SMTP id o193mr5414456qke.352.1627567197517; Thu, 29 Jul 2021 06:59:57 -0700 (PDT) MIME-Version: 1.0 References: <20210728190254.3921642-1-hca@linux.ibm.com> <20210728190254.3921642-3-hca@linux.ibm.com> In-Reply-To: From: Alexander Potapenko Date: Thu, 29 Jul 2021 15:59:21 +0200 Message-ID: Subject: Re: [PATCH 2/4] kfence: add function to mask address bits To: Sven Schnelle Cc: Heiko Carstens , Marco Elver , Vasily Gorbik , Christian Borntraeger , kasan-dev , Linux Memory Management List , LKML , linux-s390 Content-Type: text/plain; charset="UTF-8" X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 730C2B0000A7 Authentication-Results: imf19.hostedemail.com; dkim=pass header.d=google.com header.s=20161025 header.b=iOwiVk+5; dmarc=pass (policy=reject) header.from=google.com; spf=pass (imf19.hostedemail.com: domain of glider@google.com designates 209.85.222.177 as permitted sender) smtp.mailfrom=glider@google.com X-Stat-Signature: sqausmum34q5bdmfixrzpg1azurawzy5 X-HE-Tag: 1627567198-195511 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000050, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Jul 29, 2021 at 3:47 PM Sven Schnelle wrote: > > Alexander Potapenko writes: > > > On Wed, Jul 28, 2021 at 9:03 PM Heiko Carstens wrote: > >> > >> From: Sven Schnelle > >> > >> s390 only reports the page address during a translation fault. > >> To make the kfence unit tests pass, add a function that might > >> be implemented by architectures to mask out address bits. > >> > >> Signed-off-by: Sven Schnelle > >> Signed-off-by: Heiko Carstens > >> --- > >> mm/kfence/kfence_test.c | 13 ++++++++++++- > >> 1 file changed, 12 insertions(+), 1 deletion(-) > >> > >> diff --git a/mm/kfence/kfence_test.c b/mm/kfence/kfence_test.c > >> index 942cbc16ad26..eb6307c199ea 100644 > >> --- a/mm/kfence/kfence_test.c > >> +++ b/mm/kfence/kfence_test.c > >> @@ -23,8 +23,15 @@ > >> #include > >> #include > >> > >> +#include > >> + > >> #include "kfence.h" > >> > >> +/* May be overridden by . */ > >> +#ifndef arch_kfence_test_address > >> +#define arch_kfence_test_address(addr) (addr) > >> +#endif > >> + > >> /* Report as observed from console. */ > >> static struct { > >> spinlock_t lock; > >> @@ -82,6 +89,7 @@ static const char *get_access_type(const struct expect_report *r) > >> /* Check observed report matches information in @r. */ > >> static bool report_matches(const struct expect_report *r) > >> { > >> + unsigned long addr = (unsigned long)r->addr; > >> bool ret = false; > >> unsigned long flags; > >> typeof(observed.lines) expect; > >> @@ -131,22 +139,25 @@ static bool report_matches(const struct expect_report *r) > >> switch (r->type) { > >> case KFENCE_ERROR_OOB: > >> cur += scnprintf(cur, end - cur, "Out-of-bounds %s at", get_access_type(r)); > >> + addr = arch_kfence_test_address(addr); > > > > Can we normalize addr once before (or after) this switch? > > > > I don't think so. When reporing corrupted memory or an invalid free the > address is not generated by hardware but kfence itself, and therefore we > would strip valid bits. Ah, sorry, I missed that.