From patchwork Mon Jan 25 02:58:52 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anshuman Khandual X-Patchwork-Id: 12042863 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=-17.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 13E53C433DB for ; Mon, 25 Jan 2021 03:00:54 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 CABD222472 for ; Mon, 25 Jan 2021 03:00:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CABD222472 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+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=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:MIME-Version:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id: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=wtQ7Fj/aI+dIsaR644v4S/okWZG4v/3gubu3TujOrqE=; b=t5zyCVt0qtRtuKYNgqk0zKaYeT iZW4FRK5MPupvgHXdy36Ciar48fRMsHV1BPMkkORT5RazEFx3nFaJZ77+lXWM3LuH0VfQfGYdUS8z 18MH8MogJk5pUbfOspzkE40b4feeeFtD+LtGfeFWinVOu0OAXzWabEWW/0EKJ876buGG0ALY6ZujC IXal8wKKnMKhXrSxd25f4vicY2fTcY8LhP3WlojpRKo3EWnYCmmFytQbLgZOk1xrRD6r6lJPKQ93r cG78K97tFrX0fT1WJ2CICglDiUPopQ/HGYmiVgsBKXth+2I7WwTHmpaF4p89EbpJaI2eeQKftAp2n nhLIJjbw==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l3s5y-0004s9-MF; Mon, 25 Jan 2021 02:59:14 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l3s5u-0004qo-PP for linux-arm-kernel@lists.infradead.org; Mon, 25 Jan 2021 02:59:13 +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 AE7F8153B; Sun, 24 Jan 2021 18:59:08 -0800 (PST) Received: from p8cg001049571a15.arm.com (unknown [10.163.91.27]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 9FA003F66E; Sun, 24 Jan 2021 18:59:01 -0800 (PST) From: Anshuman Khandual To: linux-mm@kvack.org, akpm@linux-foundation.org, hca@linux.ibm.com, catalin.marinas@arm.com Subject: [PATCH V4 4/4] virtio-mem: check against mhp_get_pluggable_range() which memory we can hotplug Date: Mon, 25 Jan 2021 08:28:52 +0530 Message-Id: <1611543532-18698-5-git-send-email-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1611543532-18698-1-git-send-email-anshuman.khandual@arm.com> References: <1611543532-18698-1-git-send-email-anshuman.khandual@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210124_215910_983307_AC162D54 X-CRM114-Status: GOOD ( 20.46 ) 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: Mark Rutland , linux-s390@vger.kernel.org, Wei Yang , Vasily Gorbik , Anshuman Khandual , Jason Wang , David Hildenbrand , linux-kernel@vger.kernel.org, Michal Hocko , Pankaj Gupta , "Michael S. Tsirkin" , teawater , Jonathan Cameron , Pankaj Gupta , Will Deacon , Ard Biesheuvel , linux-arm-kernel@lists.infradead.org, Oscar Salvador MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: David Hildenbrand Right now, we only check against MAX_PHYSMEM_BITS - but turns out there are more restrictions of which memory we can actually hotplug, especially om arm64 or s390x once we support them: we might receive something like -E2BIG or -ERANGE from add_memory_driver_managed(), stopping device operation. So, check right when initializing the device which memory we can add, warning the user. Try only adding actually pluggable ranges: in the worst case, no memory provided by our device is pluggable. In the usual case, we expect all device memory to be pluggable, and in corner cases only some memory at the end of the device-managed memory region to not be pluggable. Cc: "Michael S. Tsirkin" Cc: Jason Wang Cc: Pankaj Gupta Cc: Oscar Salvador Cc: Wei Yang Cc: Andrew Morton Cc: catalin.marinas@arm.com Cc: teawater Cc: Anshuman Khandual Cc: Pankaj Gupta Cc: Jonathan Cameron Cc: hca@linux.ibm.com Cc: Vasily Gorbik Cc: Will Deacon Cc: Ard Biesheuvel Cc: Mark Rutland Cc: Heiko Carstens Cc: Michal Hocko Signed-off-by: David Hildenbrand Signed-off-by: Anshuman Khandual --- drivers/virtio/virtio_mem.c | 40 +++++++++++++++++++++++++------------ 1 file changed, 27 insertions(+), 13 deletions(-) diff --git a/drivers/virtio/virtio_mem.c b/drivers/virtio/virtio_mem.c index 9fc9ec4a25f5..14c17c5c1695 100644 --- a/drivers/virtio/virtio_mem.c +++ b/drivers/virtio/virtio_mem.c @@ -2222,7 +2222,7 @@ static int virtio_mem_unplug_pending_mb(struct virtio_mem *vm) */ static void virtio_mem_refresh_config(struct virtio_mem *vm) { - const uint64_t phys_limit = 1UL << MAX_PHYSMEM_BITS; + const struct range pluggable_range = mhp_get_pluggable_range(true); uint64_t new_plugged_size, usable_region_size, end_addr; /* the plugged_size is just a reflection of what _we_ did previously */ @@ -2234,15 +2234,25 @@ static void virtio_mem_refresh_config(struct virtio_mem *vm) /* calculate the last usable memory block id */ virtio_cread_le(vm->vdev, struct virtio_mem_config, usable_region_size, &usable_region_size); - end_addr = vm->addr + usable_region_size; - end_addr = min(end_addr, phys_limit); + end_addr = min(vm->addr + usable_region_size - 1, + pluggable_range.end); - if (vm->in_sbm) - vm->sbm.last_usable_mb_id = - virtio_mem_phys_to_mb_id(end_addr) - 1; - else - vm->bbm.last_usable_bb_id = - virtio_mem_phys_to_bb_id(vm, end_addr) - 1; + if (vm->in_sbm) { + vm->sbm.last_usable_mb_id = virtio_mem_phys_to_mb_id(end_addr); + if (!IS_ALIGNED(end_addr + 1, memory_block_size_bytes())) + vm->sbm.last_usable_mb_id--; + } else { + vm->bbm.last_usable_bb_id = virtio_mem_phys_to_bb_id(vm, + end_addr); + if (!IS_ALIGNED(end_addr + 1, vm->bbm.bb_size)) + vm->bbm.last_usable_bb_id--; + } + /* + * If we cannot plug any of our device memory (e.g., nothing in the + * usable region is addressable), the last usable memory block id will + * be smaller than the first usable memory block id. We'll stop + * attempting to add memory with -ENOSPC from our main loop. + */ /* see if there is a request to change the size */ virtio_cread_le(vm->vdev, struct virtio_mem_config, requested_size, @@ -2364,6 +2374,7 @@ static int virtio_mem_init_vq(struct virtio_mem *vm) static int virtio_mem_init(struct virtio_mem *vm) { + const struct range pluggable_range = mhp_get_pluggable_range(true); const uint64_t phys_limit = 1UL << MAX_PHYSMEM_BITS; uint64_t sb_size, addr; uint16_t node_id; @@ -2405,9 +2416,10 @@ static int virtio_mem_init(struct virtio_mem *vm) if (!IS_ALIGNED(vm->addr + vm->region_size, memory_block_size_bytes())) dev_warn(&vm->vdev->dev, "The alignment of the physical end address can make some memory unusable.\n"); - if (vm->addr + vm->region_size > phys_limit) + if (vm->addr < pluggable_range.start || + vm->addr + vm->region_size - 1 > pluggable_range.end) dev_warn(&vm->vdev->dev, - "Some memory is not addressable. This can make some memory unusable.\n"); + "Some device memory is not addressable/pluggable. This can make some memory unusable.\n"); /* * We want subblocks to span at least MAX_ORDER_NR_PAGES and @@ -2429,7 +2441,8 @@ static int virtio_mem_init(struct virtio_mem *vm) vm->sbm.sb_size; /* Round up to the next full memory block */ - addr = vm->addr + memory_block_size_bytes() - 1; + addr = max_t(uint64_t, vm->addr, pluggable_range.start) + + memory_block_size_bytes() - 1; vm->sbm.first_mb_id = virtio_mem_phys_to_mb_id(addr); vm->sbm.next_mb_id = vm->sbm.first_mb_id; } else { @@ -2450,7 +2463,8 @@ static int virtio_mem_init(struct virtio_mem *vm) } /* Round up to the next aligned big block */ - addr = vm->addr + vm->bbm.bb_size - 1; + addr = max_t(uint64_t, vm->addr, pluggable_range.start) + + vm->bbm.bb_size - 1; vm->bbm.first_bb_id = virtio_mem_phys_to_bb_id(vm, addr); vm->bbm.next_bb_id = vm->bbm.first_bb_id; }