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=-16.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 407F8C04FF3 for ; Mon, 24 May 2021 09:02:08 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id DC47F60FDA for ; Mon, 24 May 2021 09:02:07 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DC47F60FDA Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 16699940059; Mon, 24 May 2021 05:02:07 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 12765940055; Mon, 24 May 2021 05:02:07 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B00D0940059; Mon, 24 May 2021 05:02:06 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0063.hostedemail.com [216.40.44.63]) by kanga.kvack.org (Postfix) with ESMTP id 6FD1C940055 for ; Mon, 24 May 2021 05:02:06 -0400 (EDT) Received: from smtpin25.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 01FD56C3B for ; Mon, 24 May 2021 09:02:06 +0000 (UTC) X-FDA: 78175532652.25.EA7AA16 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by imf22.hostedemail.com (Postfix) with ESMTP id 8B71FC0042D9 for ; Mon, 24 May 2021 09:02:00 +0000 (UTC) Received: from pps.filterd (m0187473.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.43/8.16.0.43) with SMTP id 14O8v61u023666; Mon, 24 May 2021 05:01:57 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : content-transfer-encoding : mime-version; s=pp1; bh=7eX2gy/zuhS8OjiDxr2VcenOd74UiuXCuRJmJCTOZVs=; b=VEgEPFVYUm9YUeHa31Vq6bMIXPd/xHDfCVyw2NAwUGtmng3R21v0p8Uc2ehYdIayIC3o ZUwmoE8PqvLkdjsMDlAz3OvkLQSobj5Wk7TqvxJZ6aNPyR/T0Rdqc+fKqVXlEfTi+tl0 r+9NdkAaGacTnisGTcbL+eA8qgVG4a+iR+TpP+JzNwQiUvaTE3HtrHE8w+Gkua9L1CSm NlTDTykjCOfC5lYnb190mLMPitdPlcbFjOoiwfZCNKwP5RkUQ88OA10fXhlBeZiOtstU GwdTgRaxVASMH/5e+bIqqPWC9Z1UzfL4rBZmH/4ZMEw9bNklSKOiHrClzPUmZRSuRAJy mg== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 38r93803yb-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 24 May 2021 05:01:56 -0400 Received: from m0187473.ppops.net (m0187473.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.43/8.16.0.43) with SMTP id 14O8wi3g027225; Mon, 24 May 2021 05:01:56 -0400 Received: from ppma04dal.us.ibm.com (7a.29.35a9.ip4.static.sl-reverse.com [169.53.41.122]) by mx0a-001b2d01.pphosted.com with ESMTP id 38r93803xm-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 24 May 2021 05:01:56 -0400 Received: from pps.filterd (ppma04dal.us.ibm.com [127.0.0.1]) by ppma04dal.us.ibm.com (8.16.0.43/8.16.0.43) with SMTP id 14O8nPrF028826; Mon, 24 May 2021 09:01:55 GMT Received: from b01cxnp22035.gho.pok.ibm.com (b01cxnp22035.gho.pok.ibm.com [9.57.198.25]) by ppma04dal.us.ibm.com with ESMTP id 38psk8s76a-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 24 May 2021 09:01:55 +0000 Received: from b01ledav005.gho.pok.ibm.com (b01ledav005.gho.pok.ibm.com [9.57.199.110]) by b01cxnp22035.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 14O91sh636045212 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 24 May 2021 09:01:54 GMT Received: from b01ledav005.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id A366FAE05C; Mon, 24 May 2021 09:01:54 +0000 (GMT) Received: from b01ledav005.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id C52A5AE060; Mon, 24 May 2021 09:01:51 +0000 (GMT) Received: from skywalker.ibmuc.com (unknown [9.102.1.240]) by b01ledav005.gho.pok.ibm.com (Postfix) with ESMTP; Mon, 24 May 2021 09:01:51 +0000 (GMT) From: "Aneesh Kumar K.V" To: linux-mm@kvack.org, akpm@linux-foundation.org Cc: mpe@ellerman.id.au, linuxppc-dev@lists.ozlabs.org, kaleshsingh@google.com, npiggin@gmail.com, joel@joelfernandes.org, Christophe Leroy , Linus Torvalds , "Aneesh Kumar K.V" Subject: [PATCH v6 08/11] mm/mremap: properly flush the TLB on mremap. Date: Mon, 24 May 2021 14:31:11 +0530 Message-Id: <20210524090114.63446-9-aneesh.kumar@linux.ibm.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210524090114.63446-1-aneesh.kumar@linux.ibm.com> References: <20210524090114.63446-1-aneesh.kumar@linux.ibm.com> X-TM-AS-GCONF: 00 X-Proofpoint-GUID: E9Jsi4cLb3qfzd726OVY4c0xb9TlqyVJ X-Proofpoint-ORIG-GUID: 5g1Qlm1no-PwpUDg4QhE5RZcILplYtPo X-Proofpoint-UnRewURL: 0 URL was un-rewritten MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.391,18.0.761 definitions=2021-05-24_04:2021-05-20,2021-05-24 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 clxscore=1015 suspectscore=0 adultscore=0 lowpriorityscore=0 bulkscore=0 mlxscore=0 priorityscore=1501 mlxlogscore=999 impostorscore=0 spamscore=0 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2104190000 definitions=main-2105240067 X-Rspamd-Queue-Id: 8B71FC0042D9 Authentication-Results: imf22.hostedemail.com; dkim=pass header.d=ibm.com header.s=pp1 header.b=VEgEPFVY; dmarc=pass (policy=none) header.from=ibm.com; spf=pass (imf22.hostedemail.com: domain of aneesh.kumar@linux.ibm.com designates 148.163.156.1 as permitted sender) smtp.mailfrom=aneesh.kumar@linux.ibm.com X-Rspamd-Server: rspam03 X-Stat-Signature: xmsgkbht8m4hcxuh884oft4qpgxou13t X-HE-Tag: 1621846920-866106 Content-Transfer-Encoding: quoted-printable 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: As explained in commit eb66ae030829 ("mremap: properly flush TLB before releasing the pag= e") mremap is special in that it doesn't take ownership of the page. The optimized version for PUD/PMD aligned mremap also doesn't hold the ptl lo= ck. Hence flush the TLB before we update the new page table location. This en= sures the kernel invalidates the older translation cache before it can free the= page via the newly inserted translation. Fixes: c49dd3401802 ("mm: speedup mremap on 1GB or larger regions") Fixes: 2c91bd4a4e2e ("mm: speed up mremap by 20x on large regions") Link: https://lore.kernel.org/linux-mm/CAHk-=3Dwjq8thag3uNv-2MMu75OgX5ybM= on7gZDUHYwzeTwcZHoA@mail.gmail.com Signed-off-by: Aneesh Kumar K.V --- mm/mremap.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/mm/mremap.c b/mm/mremap.c index 000a71917557..8967a3707332 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -266,11 +266,13 @@ static bool move_normal_pmd(struct vm_area_struct *= vma, unsigned long old_addr, /* Clear the pmd */ pmd =3D *old_pmd; pmd_clear(old_pmd); - + /* + * flush the TLB before we move the page table entries. + */ + flush_pte_tlb_pwc_range(vma, old_addr, old_addr + PMD_SIZE); VM_BUG_ON(!pmd_none(*new_pmd)); pmd_populate(mm, new_pmd, pmd_pgtable(pmd)); =20 - flush_pte_tlb_pwc_range(vma, old_addr, old_addr + PMD_SIZE); if (new_ptl !=3D old_ptl) spin_unlock(new_ptl); spin_unlock(old_ptl); @@ -313,11 +315,14 @@ static bool move_normal_pud(struct vm_area_struct *= vma, unsigned long old_addr, /* Clear the pud */ pud =3D *old_pud; pud_clear(old_pud); + /* + * flush the TLB before we move the page table entries. + */ + flush_pte_tlb_pwc_range(vma, old_addr, old_addr + PUD_SIZE); =20 VM_BUG_ON(!pud_none(*new_pud)); =20 pud_populate(mm, new_pud, (pmd_t *)pud_page_vaddr(pud)); - flush_pte_tlb_pwc_range(vma, old_addr, old_addr + PUD_SIZE); if (new_ptl !=3D old_ptl) spin_unlock(new_ptl); spin_unlock(old_ptl); --=20 2.31.1