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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 D6634C433E0 for ; Tue, 26 May 2020 16:30:47 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 ABB4220776 for ; Tue, 26 May 2020 16:30:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org ABB4220776 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=citrix.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1jdcTH-0003Vz-4Z; Tue, 26 May 2020 16:30:31 +0000 Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1jdcTG-0003Vu-9a for xen-devel@lists.xenproject.org; Tue, 26 May 2020 16:30:30 +0000 X-Inumbo-ID: 3596f44a-9f6e-11ea-a676-12813bfff9fa Received: from esa4.hc3370-68.iphmx.com (unknown [216.71.155.144]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTPS id 3596f44a-9f6e-11ea-a676-12813bfff9fa; Tue, 26 May 2020 16:30:28 +0000 (UTC) Authentication-Results: esa4.hc3370-68.iphmx.com; dkim=none (message not signed) header.i=none IronPort-SDR: C66bPiiyt6YKoDqn5r/JZkaVknDvTkdz8iCAQJLH4uHbQspyC92LK43ixaC7HZSDdvalXk9Kij 1QdMNsQHuHF7pXkAYXUZ2pw/ts9V7Tt1sQxU5Afm6l2DzNsepCIotmfFznhD+rlo79bVI7gtF7 cbxKBQQFF2S7Bm/4QWLc+6fQFfpvIgKv1IKkLyQwEMMZbuz1bxcCI2Dqbh6F0vMsLB6xTpB4Wz jE3hf3im7nQQFP3ZCpUfGx7BzTywSkFnS0+Jf4mBzBjVWztu4PnYZzchro9xMScqESKb15tNmO qkk= X-SBRS: 2.7 X-MesageID: 19210299 X-Ironport-Server: esa4.hc3370-68.iphmx.com X-Remote-IP: 162.221.158.21 X-Policy: $RELAYED X-IronPort-AV: E=Sophos;i="5.73,437,1583211600"; d="scan'208";a="19210299" Date: Tue, 26 May 2020 18:30:21 +0200 From: Roger Pau =?utf-8?B?TW9ubsOp?= To: Martin Lucina Subject: Re: Xen PVH domU start-of-day VCPU state Message-ID: <20200526163021.GE38408@Air-de-Roger> References: <20200525160401.GA3091@nodbug.lucina.net> <6a22e477-c9e7-f0d7-6cb1-615137a778be@citrix.com> <20200526085221.GB5942@nodbug.lucina.net> <20200526093421.GA38408@Air-de-Roger> <20200526100337.GB38408@Air-de-Roger> <20200526101203.GE5942@nodbug.lucina.net> <20200526154224.GC25283@nodbug.lucina.net> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20200526154224.GC25283@nodbug.lucina.net> X-ClientProxiedBy: AMSPEX02CAS02.citrite.net (10.69.22.113) To AMSPEX02CL02.citrite.net (10.69.22.126) X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: =?utf-8?B?SsO8cmdlbiBHcm/Dnw==?= , anil@recoil.org, Andrew Cooper , mirageos-devel@lists.xenproject.org, dave@recoil.org, xen-devel@lists.xenproject.org Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" On Tue, May 26, 2020 at 05:42:24PM +0200, Martin Lucina wrote: > Oh! I think I've found a solution, even though I don't entirely understand the > problem/root cause: > > On Tuesday, 26.05.2020 at 12:12, Martin Lucina wrote: > > > On Tue, May 26, 2020 at 11:34:21AM +0200, Roger Pau Monné wrote: > > > Forgot to ask, but can you also add the output of readelf -lW > > > ? > > > > Elf file type is EXEC (Executable file) > > Entry point 0x1001e0 > > There are 7 program headers, starting at offset 64 > > > > Program Headers: > > Type Offset VirtAddr PhysAddr FileSiz MemSiz Flg Align > > INTERP 0x001000 0x0000000000100000 0x0000000000100000 0x000018 0x000018 R 0x8 > > [Requesting program interpreter: /nonexistent/solo5/] > > LOAD 0x001000 0x0000000000100000 0x0000000000100000 0x00626c 0x00626c R E 0x1000 > > LOAD 0x008000 0x0000000000107000 0x0000000000107000 0x007120 0x00ed48 RW 0x1000 > > NOTE 0x0080ac 0x00000000001070ac 0x00000000001070ac 0x000018 0x000018 R 0x4 > > NOTE 0x00f120 0x00000000001070c4 0x00000000001070c4 0x000014 0x000000 R 0x4 > ^^^^^^^^ > > I should have picked up on the above, but thought it wasn't relevant. > > > NOTE 0x008088 0x0000000000107088 0x0000000000107088 0x000024 0x000024 R 0x4 > > NOTE 0x008000 0x0000000000107000 0x0000000000107000 0x000088 0x000088 R 0x4 > > > > Section to Segment mapping: > > Segment Sections... > > 00 .interp > > 01 .interp .text .rodata .eh_frame > > 02 .note.solo5.manifest .note.solo5.abi .note.solo5.not-openbsd .data .bss > > And also the missing .note.solo5.xen above. > > > 03 .note.solo5.not-openbsd > > 04 .note.solo5.xen > > 05 .note.solo5.abi > > 06 .note.solo5.manifest > > Turns out that the .note.solo5.xen section as defined in boot.S was not > marked allocatable, and that was doing that was confusing our > linker script[1] (?). Hm, I would have said there was no need to load notes into memory, and hence using a MemSize of 0 would be fine. Maybe libelf loader was somehow getting confused and not loading the image properly? Can you paste the output of `xl -vvv create ...` when using the broken image? > > If I make this simple change: > > --- a/bindings/xen/boot.S > +++ b/bindings/xen/boot.S > @@ -32,7 +32,7 @@ > #define ENTRY(x) .text; .globl x; .type x,%function; x: > #define END(x) .size x, . - x > > -.section .note.solo5.xen > +.section .note.solo5.xen, "a", @note > > .align 4 > .long 4 > > then I get the expected output from readelf -lW, and I can get as far as > the C _start() with no issues! > > FWIW, here's the diff of readelf -lW before/after: > > --- before 2020-05-26 17:36:46.117885855 +0200 > +++ after 2020-05-26 17:38:07.090508322 +0200 > @@ -8,9 +8,9 @@ > INTERP 0x001000 0x0000000000100000 0x0000000000100000 0x000018 0x000018 R 0x8 > [Requesting program interpreter: /nonexistent/solo5/] > LOAD 0x001000 0x0000000000100000 0x0000000000100000 0x00615c 0x00615c R E 0x1000 > - LOAD 0x008000 0x0000000000107000 0x0000000000107000 0x007120 0x00ed28 RW 0x1000 > + LOAD 0x008000 0x0000000000107000 0x0000000000107000 0x006120 0x00dd28 RW 0x1000 This seems suspicious, there's a change of the size of the LOAD section, but your change to the note type should not affect the LOAD section? Hm, maybe it does because the .note.solo5.xen was considered writable by default? Roger.