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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 02DCCC369CB for ; Tue, 29 Apr 2025 07:33:24 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A038B6B0005; Tue, 29 Apr 2025 03:33:22 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9B3F16B0006; Tue, 29 Apr 2025 03:33:22 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 87D976B0007; Tue, 29 Apr 2025 03:33:22 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 69BEE6B0005 for ; Tue, 29 Apr 2025 03:33:22 -0400 (EDT) Received: from smtpin23.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id ED11BBBB3B for ; Tue, 29 Apr 2025 07:33:23 +0000 (UTC) X-FDA: 83386265886.23.8C8D074 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf18.hostedemail.com (Postfix) with ESMTP id 2B7961C0004 for ; Tue, 29 Apr 2025 07:33:21 +0000 (UTC) Authentication-Results: imf18.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=Wk7oLHDz; spf=pass (imf18.hostedemail.com: domain of rppt@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=rppt@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1745912002; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=eo8MsLguesGV9U051m7T3MCLjbQo5C/OaBcbdXKydo4=; b=MWFEUx50D5kQhOmXqCJXEn5tPhS0BU9wlzf919uS2oCYBMDr6nBn36OxRJK4RryYXN5eJ3 ovGPY6f4xUXj/JNoIU9H33ye60yKJD1efYn6lhM2A92XvsbiyB9m5nKBd6H+kwH1F+efrx 9g6PAkIo93wF97R5AGyaxNXwmhKH8ss= ARC-Authentication-Results: i=1; imf18.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=Wk7oLHDz; spf=pass (imf18.hostedemail.com: domain of rppt@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=rppt@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1745912002; a=rsa-sha256; cv=none; b=SdHa21/Hrikq3dKHPxUvFWOHZMWzmTiK8O3sKClFespNHT7PUraIfLpwc8TIRVw902L4D/ A8HuyTOUjxhT5FtyVUeKiM0dsrSG/A1Pol9KcCOt7pjqkUzIP+egwrPuR1pJObtWF71kxF trDnxL4y8KdwCJxSFKk9kZ7blNDuvXs= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id A1DF85C1D20; Tue, 29 Apr 2025 07:31:03 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6869BC4CEE3; Tue, 29 Apr 2025 07:33:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1745912000; bh=I7wnBcbNJaYz/fiGTEMW6tHkeDO3AeMTxn9cnFfWXE0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Wk7oLHDzGibPk5SXUyNUk/drmI1JeUjAiBWeKMLJTh+qWX7GsUTB5qjSD+SqB1r1e KIeGQCUdxMK5puxcy3W8pBq/8Qr/fDbK8XBxcJk4X8brQIw6lu9QLmOCUurPWLK9ef MBwQu4akkqQpeKfxCSyKpUec5VdaXPSdOL4Ss2x+FyJK6ozxKoeH6LnWQDtipSwwqQ 9yPniLnJicKpeUSZ9TiCs68xScBSHcfKlw+3wpic1iOAbgGGb0VYFYfCrdQ7jMaSsf dMvb/xKt6D/+5alfY0NEoJ9+mVjnHXv2ZFL60xUi03vv8VRMDSb2g4GOZh2nyj2D1K lNJW3tsadploQ== Date: Tue, 29 Apr 2025 10:33:12 +0300 From: Mike Rapoport To: Tom Lendacky Cc: David Hildenbrand , "Kirill A. Shutemov" , Andrew Morton , Vlastimil Babka , Mel Gorman , "Kalra, Ashish" , Rick Edgecombe , linux-mm@kvack.org, linux-coco@lists.linux.dev, linux-kernel@vger.kernel.org, Michael Roth Subject: Re: SNP guest crash in memblock with unaccepted memory Message-ID: References: <64c04e6c-43b1-996b-f83d-5fb1751debaa@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <64c04e6c-43b1-996b-f83d-5fb1751debaa@amd.com> X-Stat-Signature: 3yhfjatpfs6y3eh95fif716sm3yw3hxp X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 2B7961C0004 X-Rspam-User: X-HE-Tag: 1745912001-355174 X-HE-Meta: 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 tOJ5E8rR nzTrJsNuHgGRkjWcJdPiuW+0eP9I+rBolIls2yp2Qi+tui0VtMrXcG9kjxqBeOsYvH5WywIUZDyYdYHIRNHWbCwrSB897XToZcfK7N7x9Fu557jdbQOTbC2nyqBmB8OM20d4G1KPc40kJTkj4pHAp7Yh/+xfGRZ9y+k9HmlL5Bd1RYyVz5N2rUs6+ki9PdVSF7AiyU3qYKt5wemwL771jHzmWeLcUOztGZBHZxlpLAVtydrm+BrwlxfikF9eZdTWcqw2SPZ103XwQuR9pNXgvC62NKg== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, Apr 28, 2025 at 01:10:31PM -0500, Tom Lendacky wrote: > On 4/28/25 09:04, David Hildenbrand wrote: > > On 27.04.25 17:01, Tom Lendacky wrote: > >> Hi Kirill, > >> > >> Every now and then I experience an SNP guest boot failure for accessing > >> memory that hasn't been accepted. I managed to get a back trace: > >> > >>    RIP: 0010:memcpy_orig+0x68/0x130 > >>    Code: ... > >>    RSP: 0000:ffffffff9cc03ce8 EFLAGS: 00010006 > >>    RAX: ff11001ff83e5000 RBX: 0000000000000000 RCX: fffffffffffff000 > >>    RDX: 0000000000000bc0 RSI: ffffffff9dba8860 RDI: ff11001ff83e5c00 > >>    RBP: 0000000000002000 R08: 0000000000000000 R09: 0000000000002000 > >>    R10: 000000207fffe000 R11: 0000040000000000 R12: ffffffff9d06ef78 > >>    R13: ff11001ff83e5000 R14: ffffffff9dba7c60 R15: 0000000000000c00 > >>    memblock_double_array+0xff/0x310 > >>    memblock_add_range+0x1fb/0x2f0 > >>    memblock_reserve+0x4f/0xa0 > >>    memblock_alloc_range_nid+0xac/0x130 > >>    memblock_alloc_internal+0x53/0xc0 > >>    memblock_alloc_try_nid+0x3d/0xa0 > >>    swiotlb_init_remap+0x149/0x2f0 > >>    mem_init+0xb/0xb0 > >>    mm_core_init+0x8f/0x350 > >>    start_kernel+0x17e/0x5d0 > >>    x86_64_start_reservations+0x14/0x30 > >>    x86_64_start_kernel+0x92/0xa0 > >>    secondary_startup_64_no_verify+0x194/0x19b > >> > >> I don't know a lot about memblock, but it appears that it needs to > >> allocate more memory for it's regions array and returns a range of memory > >> that hasn't been accepted. When the memcpy() runs, the SNP guest gets a > >> #VC 0x404 because of this. > >> > >> Do you think it is as simple as calling accept_memory() on the memory > >> range returned from memblock_find_in_range() in memblock_double_array()? > > > > (not Kirill, but replying :) ) > > > > Yeah, we seem to be effectively allocating memory from memblock ("from > > ourselves") without considering that memory must be accepted first. > > > > accept_memory() on the new memory (in case of !slab) should be the right > > thing to do. > > Thanks, David. Let me add a call in for accept_memory in the !slab case > and see if that resolves it. May take a bit to repro, but should find > out eventually. I think sticking a loop of memblock_alloc() somewhere before mm_core_init() should trigger the issue. > I'll submit a patch once I verify. > > Thanks, > Tom > > > -- Sincerely yours, Mike.