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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 57D32C433F5 for ; Thu, 28 Apr 2022 15:28:25 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 9FD936B00A6; Thu, 28 Apr 2022 11:28:24 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9AD0A6B00A7; Thu, 28 Apr 2022 11:28:24 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 874926B00A8; Thu, 28 Apr 2022 11:28:24 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.hostedemail.com [64.99.140.27]) by kanga.kvack.org (Postfix) with ESMTP id 783F66B00A6 for ; Thu, 28 Apr 2022 11:28:24 -0400 (EDT) Received: from smtpin28.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay13.hostedemail.com (Postfix) with ESMTP id 53450621DF for ; Thu, 28 Apr 2022 15:28:24 +0000 (UTC) X-FDA: 79406669328.28.BEB0B1D Received: from mail-il1-f175.google.com (mail-il1-f175.google.com [209.85.166.175]) by imf21.hostedemail.com (Postfix) with ESMTP id 39B551C006F for ; Thu, 28 Apr 2022 15:28:20 +0000 (UTC) Received: by mail-il1-f175.google.com with SMTP id z12so2211091ilp.8 for ; Thu, 28 Apr 2022 08:28:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=Zmt/HybSZxPjdQpw7T2VvzfrhcZdhwr2P1u1idPPwIg=; b=Z/o1bp8J2CxNyPkfD0bNdMwfrKTJnVGI67o0Z9ewpEphoFQw+7EW3TivV3VyVy4Oz8 togmpB1Regk1FPiIV7+JowaLfnnyq5N3jIgRpAFVsiseEdDeiDDeQWHvHBC1azbgk5ns sQ/eaHxlG2HmON9b56GZlmSxShfbaTCLqtfNB7lDF3Vyt9rGnZT9id5KB/h4II7lIRD/ 9ykEfNFVLpneu98OCUZAaj1cuqnl5/gkAPveztMGbCU9dvZ12T5hQ4bGiF8gdE9d9Pfx BJvcYyFGAPGNLBpbgYc9hxc0aOqSD86ZammNwSrpvuOLGPaSu9McS1USYxOTC0fOLFII gG/w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=Zmt/HybSZxPjdQpw7T2VvzfrhcZdhwr2P1u1idPPwIg=; b=VhsZD2BkzA7nxnsMsFNWQ6eHz9eeWnULl8p0aujW6Smj+YZm64VOw0SrG7THk/Z7ZY mT5nMVXfJ4quj/RIj2QCw8dfEjqKPWLAWbWu9xDEM0vs3aC0N1cwoNj8yV0JC8EoBXMX E8yUhzMgdBWLymZfUVOgauthVQ2rnSyYj3yzdYdN/YZ5I70a8cVddLlDhHWpHkppdFH+ czVfkN5PWA4JIpZOKAqloeUR1Se2NToHszya+9uz0C8ZM94+Ix4k4h3QisC7mHa5z/e9 oufanBrbKudbupL1pln0DTVCpg7uqNrdcsUrt6BQ8bxZctDqPIDIju+kMQcIJmeD5krq Jh1Q== X-Gm-Message-State: AOAM533E6RQ+bI9IXXeCGclAoxW5el2bDWe7ibUeo1brjoCc3MrkLtJW UgpfBo+KoVIjbq4Y43lxmFq/bLbVKX584tOUnNsTI0HqD9I= X-Google-Smtp-Source: ABdhPJxIPrkF6NzQcPEXDMSZur47G8DsAopKIrUaKCtty7W9Kcf/BYPRfK4/pLE3eCaEMd1EsdgOkA4I8pagW17K2Pg= X-Received: by 2002:a05:6e02:1c24:b0:2cd:96ad:8b8a with SMTP id m4-20020a056e021c2400b002cd96ad8b8amr8162420ilh.235.1651159703117; Thu, 28 Apr 2022 08:28:23 -0700 (PDT) MIME-Version: 1.0 References: <20220428141356.GB71@qian> In-Reply-To: <20220428141356.GB71@qian> From: Andrey Konovalov Date: Thu, 28 Apr 2022 17:28:12 +0200 Message-ID: Subject: Re: [PATCH v6 00/39] kasan, vmalloc, arm64: add vmalloc tagging support for SW/HW_TAGS To: Qian Cai Cc: andrey.konovalov@linux.dev, Andrew Morton , Marco Elver , Alexander Potapenko , Dmitry Vyukov , Andrey Ryabinin , kasan-dev , Linux Memory Management List , Vincenzo Frascino , Catalin Marinas , Will Deacon , Mark Rutland , Linux ARM , Peter Collingbourne , Evgenii Stepanov , LKML , Andrey Konovalov Content-Type: text/plain; charset="UTF-8" X-Stat-Signature: 4huwqfx86azgkh5hj5bboa9mdy5z4pi9 X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 39B551C006F Authentication-Results: imf21.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b="Z/o1bp8J"; spf=pass (imf21.hostedemail.com: domain of andreyknvl@gmail.com designates 209.85.166.175 as permitted sender) smtp.mailfrom=andreyknvl@gmail.com; dmarc=pass (policy=none) header.from=gmail.com X-Rspam-User: X-HE-Tag: 1651159700-889082 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Apr 28, 2022 at 4:14 PM Qian Cai wrote: > > > SW_TAGS vmalloc tagging support is straightforward. It reuses all of > > the generic KASAN machinery, but uses shadow memory to store tags > > instead of magic values. Naturally, vmalloc tagging requires adding > > a few kasan_reset_tag() annotations to the vmalloc code. > > I could use some help here. Ever since this series, our system starts to > trigger bad page state bugs from time to time. Any thoughts? > > BUG: Bad page state in process systemd-udevd pfn:83ffffcd > page:fffffc20fdfff340 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x83ffffcd > flags: 0xbfffc0000001000(reserved|node=0|zone=2|lastcpupid=0xffff) > raw: 0bfffc0000001000 fffffc20fdfff348 fffffc20fdfff348 0000000000000000 > raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 > page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set > page_owner info is not present (never set?) Hi Qian, No ideas so far. Looks like the page has reserved tag set when it's being freed. Does this crash only happen with the SW_TAGS mode? Does this crash only happen when loading modules? Does your system have any hot-plugged memory? Thanks!