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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 561D1C54E58 for ; Wed, 20 Mar 2024 13:50:39 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rmwJx-0002mR-C9; Wed, 20 Mar 2024 09:49:33 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rmwJv-0002mD-S1 for qemu-devel@nongnu.org; Wed, 20 Mar 2024 09:49:31 -0400 Received: from mgamail.intel.com ([198.175.65.14]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rmwJs-0007eN-8C for qemu-devel@nongnu.org; Wed, 20 Mar 2024 09:49:31 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1710942568; x=1742478568; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=2PyOioHoVuIYBj44Mj1+uT2DsWCfdpZ3lXhTE0B8L9A=; b=gtFFfAm3MMbyAaYgYSjdKeIzff+DNH+f5CJ3ZXgUhNUQRkMjDWeL0av1 g5OVZ+xK6g14WFMPFf7fD2mUu++O9s6FQ4Z1je5bEIlsejfEa/Trv6UqZ uAP4UJT87cen2bB2QcaYp8MC/PGtTGuPGkABWF6deBPLawH9meFia/wJl wfR6cHVIEdF43a3fWe9xghEgBqndBFd7FfuzwL96Sj7jsmHBZMETbVHAw IoLRkFcEIvz2nuoXw6/xW2DvYHrXfCzfM6syNshjfaPOwGPEHaHeM/zXh Kdsp0QTBkKf/lU1/k3STvt3jiVHlV08JqFxYeXfIFzgJ38DgkhftGDp0t A==; X-IronPort-AV: E=McAfee;i="6600,9927,11018"; a="9680704" X-IronPort-AV: E=Sophos;i="6.07,140,1708416000"; d="scan'208";a="9680704" Received: from orviesa002.jf.intel.com ([10.64.159.142]) by orvoesa106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Mar 2024 06:49:24 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.07,140,1708416000"; d="scan'208";a="45137674" Received: from xiaoyaol-hp-g830.ccr.corp.intel.com (HELO [10.124.242.48]) ([10.124.242.48]) by orviesa002-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Mar 2024 06:49:18 -0700 Message-ID: <8a7f5bf5-9a4e-4e03-9e43-bbab53efefe9@intel.com> Date: Wed, 20 Mar 2024 21:49:14 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v5 08/65] kvm: handle KVM_EXIT_MEMORY_FAULT Content-Language: en-US To: "Wang, Lei" , Paolo Bonzini , David Hildenbrand , Igor Mammedov , Eduardo Habkost , Marcel Apfelbaum , =?UTF-8?Q?Philippe_Mathieu-Daud=C3=A9?= , Yanan Wang , "Michael S. Tsirkin" , Richard Henderson , Ani Sinha , Peter Xu , Cornelia Huck , =?UTF-8?Q?Daniel_P=2E_Berrang=C3=A9?= , Eric Blake , Markus Armbruster , Marcelo Tosatti Cc: kvm@vger.kernel.org, qemu-devel@nongnu.org, Michael Roth , Claudio Fontana , Gerd Hoffmann , Isaku Yamahata , Chenyi Qiang References: <20240229063726.610065-1-xiaoyao.li@intel.com> <20240229063726.610065-9-xiaoyao.li@intel.com> <3d2655c7-74ad-49d9-a527-7648f8e565da@intel.com> From: Xiaoyao Li In-Reply-To: <3d2655c7-74ad-49d9-a527-7648f8e565da@intel.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=198.175.65.14; envelope-from=xiaoyao.li@intel.com; helo=mgamail.intel.com X-Spam_score_int: -14 X-Spam_score: -1.5 X-Spam_bar: - X-Spam_report: (-1.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.417, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, HK_RANDOM_ENVFROM=0.001, HK_RANDOM_FROM=0.999, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On 3/19/2024 10:14 AM, Wang, Lei wrote: > On 2/29/2024 14:36, Xiaoyao Li wrote: >> From: Chao Peng >> >> When geeting KVM_EXIT_MEMORY_FAULT exit, it indicates userspace needs to >> do the memory conversion on the RAMBlock to turn the memory into desired >> attribute, i.e., private/shared. >> >> Currently only KVM_MEMORY_EXIT_FLAG_PRIVATE in flags is valid when >> KVM_EXIT_MEMORY_FAULT happens. >> >> Note, KVM_EXIT_MEMORY_FAULT makes sense only when the RAMBlock has >> guest_memfd memory backend. >> >> Note, KVM_EXIT_MEMORY_FAULT returns with -EFAULT, so special handling is >> added. >> >> When page is converted from shared to private, the original shared >> memory can be discarded via ram_block_discard_range(). Note, shared >> memory can be discarded only when it's not back'ed by hugetlb because >> hugetlb is supposed to be pre-allocated and no need for discarding. >> >> Signed-off-by: Chao Peng >> Co-developed-by: Xiaoyao Li >> Signed-off-by: Xiaoyao Li >> >> --- >> Changes in v4: >> - open-coded ram_block_discard logic; >> - change warn_report() to error_report(); (Daniel) >> --- >> accel/kvm/kvm-all.c | 94 ++++++++++++++++++++++++++++++++++++++++----- >> 1 file changed, 84 insertions(+), 10 deletions(-) >> >> diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c >> index 70d482a2c936..87e4275932a7 100644 >> --- a/accel/kvm/kvm-all.c >> +++ b/accel/kvm/kvm-all.c >> @@ -2903,6 +2903,68 @@ static void kvm_eat_signals(CPUState *cpu) >> } while (sigismember(&chkset, SIG_IPI)); >> } >> >> +static int kvm_convert_memory(hwaddr start, hwaddr size, bool to_private) >> +{ >> + MemoryRegionSection section; >> + ram_addr_t offset; >> + MemoryRegion *mr; >> + RAMBlock *rb; >> + void *addr; >> + int ret = -1; >> + >> + if (!QEMU_PTR_IS_ALIGNED(start, qemu_host_page_size) || >> + !QEMU_PTR_IS_ALIGNED(size, qemu_host_page_size)) { >> + return -1; >> + } >> + >> + if (!size) { >> + return -1; >> + } >> + >> + section = memory_region_find(get_system_memory(), start, size); >> + mr = section.mr; >> + if (!mr) { >> + return -1; >> + } >> + >> + if (memory_region_has_guest_memfd(mr)) { >> + if (to_private) { >> + ret = kvm_set_memory_attributes_private(start, size); >> + } else { >> + ret = kvm_set_memory_attributes_shared(start, size); >> + } >> + >> + if (ret) { >> + memory_region_unref(section.mr); >> + return ret; >> + } >> + >> + addr = memory_region_get_ram_ptr(mr) + section.offset_within_region; >> + rb = qemu_ram_block_from_host(addr, false, &offset); >> + >> + if (to_private) { >> + if (rb->page_size != qemu_host_page_size) { >> + /* >> + * shared memory is back'ed by hugetlb, which is supposed to be >> + * pre-allocated and doesn't need to be discarded >> + */ > > Nit: comment indentation is broken here. > >> + return 0; >> + } else { >> + ret = ram_block_discard_range(rb, offset, size); >> + } >> + } else { >> + ret = ram_block_discard_guest_memfd_range(rb, offset, size); >> + } >> + } else { >> + error_report("Convert non guest_memfd backed memory region " >> + "(0x%"HWADDR_PRIx" ,+ 0x%"HWADDR_PRIx") to %s", > > Same as above. > Fixed. thanks!