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 4E262C433EF for ; Mon, 20 Dec 2021 09:25:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230408AbhLTJZE (ORCPT ); Mon, 20 Dec 2021 04:25:04 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:57417 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229812AbhLTJZD (ORCPT ); Mon, 20 Dec 2021 04:25:03 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1639992301; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=Nnk2J4ZoXBtJE9rH5Olhc2v3ow2o0jQFMpDHq6LmjfY=; b=HDaoGsW3dxlMHccLchAocZIxgbMJEg7V4d3cubwlhKRX5i/2/PvSVparaIXn6rKGxukFFi 4yN4k2F2SzbgZol2hIShdVCjzt8BLaFaX2DybHxEKEbTLgqa8pmByx2w0COknkzrWAbgJg 5v6r4fTQqZAJ5OqWXvy7wiz2w7LH0WI= Received: from mail-ed1-f71.google.com (mail-ed1-f71.google.com [209.85.208.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-2-W1wLzSbCM2OQZlXWmvcx4Q-1; Mon, 20 Dec 2021 04:23:38 -0500 X-MC-Unique: W1wLzSbCM2OQZlXWmvcx4Q-1 Received: by mail-ed1-f71.google.com with SMTP id y17-20020a056402271100b003f7ef5ca612so7029761edd.17 for ; Mon, 20 Dec 2021 01:23:38 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:in-reply-to:references:date :message-id:mime-version; bh=Nnk2J4ZoXBtJE9rH5Olhc2v3ow2o0jQFMpDHq6LmjfY=; b=gKtCctOzSlUTHQ0dKxWUvE8OriW01wEKRWbASdkkhAEJvUETn3KN6o/H7ChP87erpf 48mbThXBXc5o7HUiJk7jMaD0CxeDiSWwmjutsguEtkvFo2fZT5CHJAZhVRIG8TU1xS/c FyzTyeuYFGmXRE6XIfp3aluy2nPmbPXuW/DOl8wMnCcaQY93bryZogoV+AIlA90RwXtG ddjmzwG/H0JBfeNMD+0X1gVhXoAui0k6cN8wM+0vWTuVm4wI+b7unixob5TYHwnABJwl u7dFggaNND2czSFB5IjJ8+fi3VhV5pYc8UnAmIEgp4Yh4as9JFJ/Fog7MMmeM9R+TCIn ozDg== X-Gm-Message-State: AOAM530f+59YfCobZtV4PyQsOioiFqnv21rWkrJTfJX0YPFP3F6tRwHd dlRtNuE8fkQsLHkF9xGGeaya6os+RNJNeNv/ljUpFZg+jceIUHrmQLWqYUpmAjgYKVRzi0m10O5 L8gZxQf70kAqaBSlI0gwst3cW X-Received: by 2002:a05:6402:c0a:: with SMTP id co10mr14695516edb.295.1639992217400; Mon, 20 Dec 2021 01:23:37 -0800 (PST) X-Google-Smtp-Source: ABdhPJzUAbBEWaDB55xFPv1shMHEPRY0K/FLkT72nUjo6PPZahsoOBnw0777NBsB1oiVAcMaXdj8AQ== X-Received: by 2002:a05:6402:c0a:: with SMTP id co10mr14695500edb.295.1639992217232; Mon, 20 Dec 2021 01:23:37 -0800 (PST) Received: from fedora (nat-2.ign.cz. [91.219.240.2]) by smtp.gmail.com with ESMTPSA id j11sm6434339edv.0.2021.12.20.01.23.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 20 Dec 2021 01:23:36 -0800 (PST) From: Vitaly Kuznetsov To: Andra Paraschiv , linux-kernel Cc: Alexandru Ciobotaru , Greg KH , Alexandru Vasile , Marcelo Cerri , Paolo Bonzini , Stefano Garzarella , Stefan Hajnoczi , Tim Gardner , kvm , ne-devel-upstream , stable , Andra Paraschiv Subject: Re: [PATCH =?utf-8?Q?v1=C2=A0=5D?= nitro_enclaves: Add mmap_read_lock() for the get_user_pages() call In-Reply-To: <20211218103525.26739-1-andraprs@amazon.com> References: <20211218103525.26739-1-andraprs@amazon.com> Date: Mon, 20 Dec 2021 10:23:35 +0100 Message-ID: <87o85btyso.fsf@redhat.com> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Andra Paraschiv writes: > After commit 5b78ed24e8ec (mm/pagemap: add mmap_assert_locked() > annotations to find_vma*()), the call to get_user_pages() will trigger > the mmap assert. > > static inline void mmap_assert_locked(struct mm_struct *mm) > { > lockdep_assert_held(&mm->mmap_lock); > VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_lock), mm); > } > > [ 62.521410] kernel BUG at include/linux/mmap_lock.h:156! > ........................................................... > [ 62.538938] RIP: 0010:find_vma+0x32/0x80 > ........................................................... > [ 62.605889] Call Trace: > [ 62.608502] > [ 62.610956] ? lock_timer_base+0x61/0x80 > [ 62.614106] find_extend_vma+0x19/0x80 > [ 62.617195] __get_user_pages+0x9b/0x6a0 > [ 62.620356] __gup_longterm_locked+0x42d/0x450 > [ 62.623721] ? finish_wait+0x41/0x80 > [ 62.626748] ? __kmalloc+0x178/0x2f0 > [ 62.629768] ne_set_user_memory_region_ioctl.isra.0+0x225/0x6a0 [nitro_enclaves] > [ 62.635776] ne_enclave_ioctl+0x1cf/0x6d7 [nitro_enclaves] > [ 62.639541] __x64_sys_ioctl+0x82/0xb0 > [ 62.642620] do_syscall_64+0x3b/0x90 > [ 62.645642] entry_SYSCALL_64_after_hwframe+0x44/0xae > > Add mmap_read_lock() for the get_user_pages() call when setting the > enclave memory regions. > > Signed-off-by: Andra Paraschiv > Cc: stable@vger.kernel.org In case commit 5b78ed24e8ec broke Nitro Enclaves driver, we need to explicitly state this: Fixes: 5b78ed24e8ec ("mm/pagemap: add mmap_assert_locked() annotations to find_vma*()") > --- > drivers/virt/nitro_enclaves/ne_misc_dev.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/virt/nitro_enclaves/ne_misc_dev.c b/drivers/virt/nitro_enclaves/ne_misc_dev.c > index 8939612ee0e0..6c51ff024036 100644 > --- a/drivers/virt/nitro_enclaves/ne_misc_dev.c > +++ b/drivers/virt/nitro_enclaves/ne_misc_dev.c > @@ -886,8 +886,13 @@ static int ne_set_user_memory_region_ioctl(struct ne_enclave *ne_enclave, > goto put_pages; > } > > + mmap_read_lock(current->mm); > + > gup_rc = get_user_pages(mem_region.userspace_addr + memory_size, 1, FOLL_GET, > ne_mem_region->pages + i, NULL); > + > + mmap_read_unlock(current->mm); > + This looks very much like get_user_pages_unlocked(), I think we can use it instead of open-coding it. > if (gup_rc < 0) { > rc = gup_rc; -- Vitaly