From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-wy0-f177.google.com ([74.125.82.177]) by canuck.infradead.org with esmtps (Exim 4.72 #1 (Red Hat Linux)) id 1PtMsR-0006TM-Pm for kexec@lists.infradead.org; Sat, 26 Feb 2011 16:20:16 +0000 Received: by wyf23 with SMTP id 23so2629397wyf.36 for ; Sat, 26 Feb 2011 08:20:13 -0800 (PST) Date: Sat, 26 Feb 2011 18:20:08 +0200 From: "Ahmed S. Darwish" Subject: Saveoops: Making Kexec purgatory position-independent? Message-ID: <20110226162008.GA23879@laptop> MIME-Version: 1.0 Content-Disposition: inline List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: kexec-bounces@lists.infradead.org Errors-To: kexec-bounces+dwmw2=twosheds.infradead.org@lists.infradead.org To: "Eric W. Biederman" , Simon Horman , Vivek Goyal , Haren Myneni Cc: Ingo Molnar , X86-ML , KEXEC-ML , "H. Peter Anvin" Hi, I'm continuing work on 'Saveoops', saving both early and normal Linux oops log to disk upon panic [*], using Kexec and bootloaders this time. Purgatory, the transitional mini-kernel used by kexec, is a relocatable ELF file. Userspace kexec-tools finds the final load address of such code (by parsing /proc/iomem, etc) and then applies the relocations itself before passing the now-ready executable image to kernel. Since capturing early oopses is the major goal, doing such relocation in userspace won't fit my purposes. Two options remain: - relocate purgatory entries in the kernel early boot path - or compile purgatory as position-independent, thus simplifying the kernel load logic The former will add extra logic in a sensitive path (early boot), while the latter will require changes inside the purgatory code itself, especially i386 assembly files. Any preferable option from our kexec and x86 maintainers? thanks! [*] http://news.gmane.org/find-root.php?message_id=<20110125134748.GA10051@laptop> http://news.gmane.org/find-root.php?message_id=<20110126124954.GC24527@laptop> -- Darwish http://darwish.07.googlepages.com _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec