[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: Problem loading linux 5.19 as PV dom0
- To: Juergen Gross <jgross@xxxxxxxx>
- From: Jan Beulich <jbeulich@xxxxxxxx>
- Date: Thu, 23 Jun 2022 09:55:25 +0200
- Arc-authentication-results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=suse.com; dmarc=pass action=none header.from=suse.com; dkim=pass header.d=suse.com; arc=none
- Arc-message-signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=+Bo62bnXYwnaQMPoWppPDTRVPRld4i9FNVCzazkNfGo=; b=UBYlr1lpvcWjxYtTI7B+3G0Xi9z86aKIZ+PAjjTnucGV/felE4FbtiFL5KABR7Kq52+ONPdfmNaZpA2Kg0aR8OHl7x5CE/9Q7Svot4Otq74K09S54yQ9IKlnTmLRSBPKwZy8GALMAZTJS1FKHkFmmbQbFtiQdmEqvPk3X797HKT7JMoCjse1xxPmekwo3H27h/sALyrOjCS6FMF+aaBThkZIyfn2r78CG9zDkdEmwl/guGg4rkLc8kil2CvhD6gBjRcAQb6F2hWgMXo0oXp7EWMmUalgQYQwF0Qc/y6Md9o46l+NtajrdwjOp+gVtOFCCyI2eZgY40ZLfajNN/rMpA==
- Arc-seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=bZAnf3Wtpq8OuIx/C3sxvcDcWKxGGaeQKKGhKwkbiMFz+GUnGFHjcFsTiXxHOzewSB/b+dteXvhOv3wisRqefYU461g/8Sdfb1yzroUCcHQcSnfziPWUlugoesCjGGemWqy5xUab0vS7BBlGzfeWhXXcwrtNPonW56ApJwGIrVkrJMyQINc2c8/K/vYrfzzAQK+3vve7t2TgoMHLNQpKbuNtFC8/P4g7lGjsG4hbvoPRQqsirbkWHA4vhz8vxna9sfdQL3WWMbeI0Wt2Uwg+J4oOaggV3MjgPJvcTyOZfUyKhbOgXmt6778ZBlEq5XEGDmUdi59Z3/Gatj3yX3ON3g==
- Authentication-results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=suse.com;
- Cc: "xen-devel@xxxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxxx>
- Delivery-date: Thu, 23 Jun 2022 07:55:33 +0000
- List-id: Xen developer discussion <xen-devel.lists.xenproject.org>
On 22.06.2022 18:06, Juergen Gross wrote:
> A Linux kernel 5.19 can only be loaded as dom0, if it has been
> built with CONFIG_AMD_MEM_ENCRYPT enabled. This is due to the
> fact that otherwise the (relevant) last section of the built
> kernel has the NOLOAD flag set (it is still marked with
> SHF_ALLOC).
>
> I think at least the hypervisor needs to be changed to support
> this layout. Otherwise it will put the initial page tables for
> dom0 at the same position as this last section, leading to
> early crashes.
Isn't Xen using the bzImage header there, rather than any ELF
one? In which case it would matter how the NOLOAD section is
actually represented in that header. Can you provide a dump (or
binary representation) of both headers?
Jan
> A workaround in the kernel would be to always add a small
> section at the end which needs to be loaded (like is done
> with CONFIG_AMD_MEM_ENCRYPT set), but I don't think we can
> put this burden on all guests being capable to run in PV
> mode.
>
> I haven't tested yet, whether unprivileged PV guests are
> affected, too.
>
>
> Juergen
|
