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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 877B3C54FCB for ; Wed, 22 Apr 2020 14:26:51 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 56AD62084D for ; Wed, 22 Apr 2020 14:26:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="hENhUXrt" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 56AD62084D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=LvxLdN8if83wpr6nn9TntW32HItFWw/OLmljc4r7bCY=; b=hENhUXrtDpXonv U8fVLX+RLhZbO6Sqv+VS2QsuNoZXb+n+imm+T5QfA7sbPUmVIELy3QsmgMp577594CFRUtSmdBSW7 vXe7tOO6P6tgWPSm7oLcYR+mgn7JjYFdl6i2LJTknamlb7Dqo0Cz/Y8IWF9h1WwvG3Jjv0s4e4HCP hBIVWMKugcPRs/LshNHsVhdjNEyfXx5AC06wrOTCQe8CNr72D5pEoU/movGYublHnraGqNaMBinkp ZzzOfkLYMQoqsoLInAYvxWFLbpDWkXXH3KWXapYGr6X01c5mHbmkFlBF/AJ5MId2txag6R18DnM3m Mq7oQuIy/2Sqr+0+QhPQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jRGKs-0001aU-3l; Wed, 22 Apr 2020 14:26:46 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jRGJw-0000fy-Cm for linux-arm-kernel@lists.infradead.org; Wed, 22 Apr 2020 14:25:50 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 036B91042; Wed, 22 Apr 2020 07:25:48 -0700 (PDT) Received: from e112269-lin.arm.com (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 8D26A3F68F; Wed, 22 Apr 2020 07:25:46 -0700 (PDT) From: Steven Price To: linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org Subject: [PATCH 4/4] arm64: mte: Save tags when hibernating Date: Wed, 22 Apr 2020 15:25:30 +0100 Message-Id: <20200422142530.32619-5-steven.price@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200422142530.32619-1-steven.price@arm.com> References: <20200422142530.32619-1-steven.price@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200422_072548_562541_C1ED4E1E X-CRM114-Status: GOOD ( 14.60 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arch@vger.kernel.org, Arnd Bergmann , Catalin Marinas , Hugh Dickins , Steven Price , Andrew Morton , Vincenzo Frascino , Will Deacon Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org When hibernating the contents of all pages in the system are written to disk, however the MTE tags are not visible to the generic hibernation code. So just before the hibernation image is created copy the tags out of the physical tag storage into standard memory so they will be included in the hibernation image. After hibernation apply the tags back into the physical tag storage. Signed-off-by: Steven Price --- arch/arm64/kernel/hibernate.c | 116 ++++++++++++++++++++++++++++++++++ 1 file changed, 116 insertions(+) diff --git a/arch/arm64/kernel/hibernate.c b/arch/arm64/kernel/hibernate.c index 5b73e92c99e3..b89429778b5d 100644 --- a/arch/arm64/kernel/hibernate.c +++ b/arch/arm64/kernel/hibernate.c @@ -31,6 +31,7 @@ #include #include #include +#include #include #include #include @@ -277,6 +278,115 @@ static int create_safe_exec_page(void *src_start, size_t length, #define dcache_clean_range(start, end) __flush_dcache_area(start, (end - start)) +#ifdef CONFIG_ARM64_MTE + +static DEFINE_XARRAY(mte_pages); + +static int save_tags(struct page *page, unsigned long pfn) +{ + void *tag_storage, *ret; + + tag_storage = mte_allocate_tag_storage(); + if (!tag_storage) + return -ENOMEM; + + mte_save_page_tags(page_address(page), tag_storage); + + ret = xa_store(&mte_pages, pfn, tag_storage, GFP_KERNEL); + if (WARN(xa_is_err(ret), "Failed to store MTE tags")) { + mte_free_tag_storage(tag_storage); + return xa_err(ret); + } else if (WARN(ret, "swsusp: %s: Duplicate entry", __func__)) { + mte_free_tag_storage(ret); + } + + return 0; +} + +static void swsusp_mte_free_storage(void) +{ + XA_STATE(xa_state, &mte_pages, 0); + void *tags; + + xa_lock(&mte_pages); + xas_for_each(&xa_state, tags, ULONG_MAX) { + mte_free_tag_storage(tags); + } + xa_unlock(&mte_pages); + + xa_destroy(&mte_pages); +} + +static int swsusp_mte_save_tags(void) +{ + struct zone *zone; + unsigned long pfn, max_zone_pfn; + int ret = 0; + int n = 0; + + if (!system_supports_mte()) + return 0; + + for_each_populated_zone(zone) { + max_zone_pfn = zone_end_pfn(zone); + for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) { + struct page *page = pfn_to_online_page(pfn); + + if (!page) + continue; + + if (!test_bit(PG_mte_tagged, &page->flags)) + continue; + + ret = save_tags(page, pfn); + n++; + + if (ret) { + swsusp_mte_free_storage(); + goto out; + } + } + } + + pr_info("Saved %d MTE pages\n", n); + +out: + return ret; +} + +static void swsusp_mte_restore_tags(void) +{ + XA_STATE(xa_state, &mte_pages, 0); + int n = 0; + void *tags; + + xa_lock(&mte_pages); + xas_for_each(&xa_state, tags, ULONG_MAX) { + unsigned long pfn = xa_state.xa_index; + struct page *page = pfn_to_online_page(pfn); + + mte_restore_page_tags(page_address(page), tags); + + mte_free_tag_storage(tags); + n++; + } + xa_unlock(&mte_pages); + + pr_info("Restored %d MTE pages\n", n); + + xa_destroy(&mte_pages); +} +#else +static int swsusp_mte_save_tags(void) +{ + return 0; +} + +static void swsusp_mte_restore_tags(void) +{ +} +#endif + int swsusp_arch_suspend(void) { int ret = 0; @@ -294,6 +404,10 @@ int swsusp_arch_suspend(void) /* make the crash dump kernel image visible/saveable */ crash_prepare_suspend(); + ret = swsusp_mte_save_tags(); + if (ret) + return ret; + sleep_cpu = smp_processor_id(); ret = swsusp_save(); } else { @@ -307,6 +421,8 @@ int swsusp_arch_suspend(void) dcache_clean_range(__hyp_text_start, __hyp_text_end); } + swsusp_mte_restore_tags(); + /* make the crash dump kernel image protected again */ crash_post_resume(); -- 2.20.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel