From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 9F7BD547057; Tue, 29 Sep 2026 22:17:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790720234; cv=none; b=I95mrVb1o7+tFEDF050Ll4OLR2FdKgjHQ6fLCpAnJw3v0v9d/JnaiEJ2TJkktfFjIRaC0BppcfCbme57zhnadOlEGyoC8mt6Tpg1X/UWKYMdejPfrFCWDb86ES/UJPBew5bMWUXVLjp72jupuSvzP/G3G5XFMGN9RsWxVuZxhZs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790720234; c=relaxed/simple; bh=2U+cAcr8VcJVMr34PG0rQs6SPss8l1YbdTIFge5eJ3M=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ui3PhHV1Lb/QEqsrG02UpsYiH4v7DXkagDKbAqqLYPSnunj6cBliF9HGD/RNoOkElObzvlY4RH1MXfiw9lOHCDodOcDFCINx3XxKzTGAJCwkxSSYgR6dTJL/+AzKglkxS/vvHQ5p1gCThmuwJ+lLJHp6/0H3ThkBZ9I5N11WS94= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=XQoSVaj/; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="XQoSVaj/" 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 AC3CB1682; Tue, 29 Sep 2026 15:17:09 -0700 (PDT) Received: from ewhatever.cambridge.arm.com (ewhatever.cambridge.arm.com [10.2.197.99]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 6839F3F85F; Tue, 29 Sep 2026 15:17:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1790720233; bh=2U+cAcr8VcJVMr34PG0rQs6SPss8l1YbdTIFge5eJ3M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XQoSVaj/joHDiB+a+Td9/wqeuygHIGRa4x9oWLe7eEDb/5FM0lKIoXcXl92wLTSB1 B1gw19h9UeWXp9nJ/EEuVZHgoXwvANX1XUVZaIllSXlm0ryyN/q5u7yL9yXvwkjvvP +XUVKbXkU3aJ9LfMpmsO5X3er6QaCrnS6hKe+kaE= From: Suzuki K Poulose To: kvm@vger.kernel.org, kvmarm@lists.linux.dev Cc: maz@kernel.org, will@kernel.org, catalin.marinas@arm.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, steven.price@arm.com, aneesh.kumar@kernel.org, oupton@kernel.org, gshan@redhat.com, joey.gouly@arm.com, tabba@google.com, yuzenghui@huawei.com, linux-coco@lists.linux.dev, gankulkarni@os.amperecomputing.com, sdonthineni@nvidia.com, alpergun@google.com, fj0570is@fujitsu.com, WeiLin.Chang@arm.com, lpieralisi@kernel.org, enju.kohei@fujitsu.com, sudeep.holla@arm.com, jonathan.cameron@oss.qualcomm.com, Suzuki K Poulose , David Hildenbrand Subject: [PATCH v20 9/9] firmware: arm_rmm: hotplug: Skip memory added to ZONE_MOVABLE Date: Tue, 29 Sep 2026 23:16:23 +0100 Message-ID: <20260929221623.1342076-10-suzuki.poulose@arm.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260929221623.1342076-1-suzuki.poulose@arm.com> References: <20260929221623.1342076-1-suzuki.poulose@arm.com> Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit If the hotadded memory is in ZONE_MOVABLE, we could allow that to proceed without the RMM having fine grained tracking, as we won't allocate pages from there for guest-memfd or kernel allocation Cc: Catalin Marinas Cc: David Hildenbrand (Arm) Signed-off-by: Suzuki K Poulose --- Changes since v19: - New patch in v20, keeping this at the tail to allow for the rest of the series to proceed, while this patch gets discussed. --- drivers/firmware/arm_rmm/rmi.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/firmware/arm_rmm/rmi.c b/drivers/firmware/arm_rmm/rmi.c index d4d098448e46e..ef0a171ba9677 100644 --- a/drivers/firmware/arm_rmm/rmi.c +++ b/drivers/firmware/arm_rmm/rmi.c @@ -1043,6 +1043,18 @@ static int rmi_memory_notifier(struct notifier_block *nb, start = PFN_PHYS(arg->start_pfn); end = PFN_PHYS(arg->start_pfn + arg->nr_pages); + /* + * If the hotplugged memory region is in ZONE_MOVABLE, neither the + * guest-memfd nor the kernel allocations can come from there. So we are + * fine to skip this. + * For boot time memory, we don't allow this discount, as the + * decision to move boot memory pages to ZONE_MOVABLE is purely + * a kernel choice and the firmware must have decided what it covers. + */ + if (page_zonenum(pfn_to_page(arg->start_pfn)) == ZONE_MOVABLE && + page_zonenum(pfn_to_page(arg->start_pfn + arg->nr_pages - 1)) == ZONE_MOVABLE) + return NOTIFY_DONE; + ret = rmi_prepare_memory(start, end); return notifier_from_errno(ret); -- 2.43.0