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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 ECCFAF8D762 for ; Thu, 16 Apr 2026 16:40:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type:MIME-Version: Message-ID:Date:References:In-Reply-To:Subject:Cc:To:From:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=IUZqLd1e6mQtA0r/0InujOn54jhuCfx3vO3Aq70vCls=; b=ru+Xb8nEz9Lmmrm9674pizVX6X WDj34j0caOywpjx2go2KwrV/OffAx+JQ3PMJVU0ylfRn2BOPtWjRIEr1VZjCnkRjSpWZT2lcnEli7 o7oCRnThoFOW+F4PuS5WHaX5pqCIfipVsC+QFK5jLjCLGIn736mxJQJQs2hCljsq8THdTVyT/Wdxi iUYxWb1YGokJfk3K83DmXA+1vURmkeyBA0PDQB2W6L9ukSeOlPLjfu97rg0Qtl4Lt59+XHgO7seyc 8MnAcuSnwg1iSwIjby7aDvPH1Mu3AB5E1HHGWmakJH+Z/23sw4qdgINJwzuPH+zWZJP9Corc19vZa XYO9YOvQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1wDPln-00000002fxK-3uMx; Thu, 16 Apr 2026 16:40:47 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1wDPll-00000002fwm-2In5 for kexec@lists.infradead.org; Thu, 16 Apr 2026 16:40:46 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 72A26440E8; Thu, 16 Apr 2026 16:40:43 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C4E96C2BCAF; Thu, 16 Apr 2026 16:40:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1776357643; bh=lCGmJ3F+1zjEehNS6SOPtlYDsWuMjRcxlWpNpztwY20=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=bX6Niq2fCvU2FntF15yZDWJ/6kd2Cd766Rcq3gRZajZ7zH3dwUYzJXmr3v8Ej0VpI Y+ZtIqhAupEVlrXQmQ8VS3DghuyFB5ZRtY0zXOhvSgnMw97KPaucJzr4KinUEczUZt vbwJSi8fzOpDoIxZJa5Skk/0FyALPGDeCO96pXFXimupZpphGc0JKQEtmSQ/bi3c3V 7kEbSX0DJbwviS1cRP2J1VRrqS2AdpcLykzDmygRjkuduwfIPwBPhsAnu2Jf+JO97C QPFjR8EZgaVOY4z2jDxxSJMLj/PyyrwZLTSwAQS55NRu/jGwNQ+TDD1mCHqRNGdOFf Rh+gML+PhNJ0Q== From: Pratyush Yadav To: Evangelos Petrongonas Cc: Pratyush Yadav , "Mike Rapoport (Microsoft)" , Alexander Graf , Pasha Tatashin , Rob Herring , Saravana Kannan , Changyuan Lyu , Andrew Morton , , , , Subject: Re: [PATCH v2] kho: skip KHO for crash kernel In-Reply-To: <20260416161744.GA65710@dev-dsk-epetron-1c-1d4d9719.eu-west-1.amazon.com> (Evangelos Petrongonas's message of "Thu, 16 Apr 2026 16:17:44 +0000") References: <20260410011609.1103-1-epetron@amazon.de> <2vxztstf7ys7.fsf@kernel.org> <20260416161744.GA65710@dev-dsk-epetron-1c-1d4d9719.eu-west-1.amazon.com> Date: Thu, 16 Apr 2026 16:40:39 +0000 Message-ID: <2vxz8qam7ta0.fsf@kernel.org> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260416_094045_647730_C0DBEC74 X-CRM114-Status: GOOD ( 17.92 ) X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "kexec" Errors-To: kexec-bounces+kexec=archiver.kernel.org@lists.infradead.org On Thu, Apr 16 2026, Evangelos Petrongonas wrote: > On Mon, Apr 13, 2026 at 01:52:40PM +0000 Pratyush Yadav wrote: >> Hi Evangelos, >> >> On Fri, Apr 10 2026, Evangelos Petrongonas wrote: [...] >> > Note regarding backporting >> > The offending commit was deployed with 6.19. The only other supported >> > kernel version with 6.18, unless I miss someting uses >> > ``` >> > if (!kho_out.finalized) >> > ``` >> > which in the case of crash kernel it shouldn't be finalised. >> >> While normally you should load the crash kernel early in boot and at >> that point KHO should not be finalized, I don't see anything that >> prevents crash kernel from being loaded after finalize. In which case, >> you can trigger this bug before d7255959b69a ("kho: allow kexec load >> before KHO finalization") as well. Also, before f322a97aeb2a ("kho: only >> fill kimage if KHO is finalized") (landed in v6.18) kho_fill_kimage() >> was also guarded by if (!kho_enable). So you'd hit this bug in all >> kernels before that point in the very same way as today. >> >> So should we update Fixes to 3bdecc3c93f9 ("kexec: add KHO support to >> kexec file loads") and Cc stable? >> > But in this case it seems a userspace misuse if it finalizes kho for > crash kernel. Whereas with the current state we hit the bug with a sane > userspace. Yeap we would hit that in earlier kernel than 6.18, but none > with KHO is supported is it? > > I don't have strong objection for backporting it to 6.18, but it feels > unnecessary. Fair enough. Let's leave it as it is then. [...] -- Regards, Pratyush Yadav