From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A1A4523ABA0 for ; Sun, 30 Nov 2025 02:56:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764471408; cv=none; b=JibXhZpygtwqyPxkCZ7S2R6cZh3LNuRcxy75OylunI2VBOmkzFg11VtAaK0IOmwT6ten9gVHw4OLrR/NbP+SjYgwuGWtYO6Rfs0/wcIJA8GQbLWqesvvuqcaouuJND5w0bcCIs9vOaSNt7rQmhRxvLAjCEMNrRPiv+t88BEjrGQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764471408; c=relaxed/simple; bh=YFkzRqo3OUlq5AUGRJgGx5Ym68sf4ZGFgfMZNfTlvSI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=M3K0l2X6aYHKZTXX6lvmtVaTFCKCxaChizKSEhclZSQ237GBHJnz4KN8IRMVTT2S9U06tf+13iw65qKa4pJq5Vv00Le9XtmiIU/pjlzHL/Z29+mbu+FeWcQywQm5CuK6O+hOq92zvGHZa4oGjP/ChDwTvz22dEFAbfS5kfrFItI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=ModiT8XP; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="ModiT8XP" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1764471405; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=O+TZ5IvwVAJilCgStks8oRIyF+Xcnm6BlG3sJPZcOWo=; b=ModiT8XP+uDushnjsZmcI+IsdDETdajWSL0wBXSK0AjtjAKnSwOFjNpYB52gw85Rspb1Vh LA1AK3oqPjvhoqEtOZFiN3+liO7tp5oZfuBPBIh04Sc99XUdZ+oZ4qAsU2RKlrzGS6lafX yg4X3XZFqPIwQiD00rKh2LL3spawS98= Received: from mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-683-4CZnjbkNNsSlXUHxWAjX5g-1; Sat, 29 Nov 2025 21:56:42 -0500 X-MC-Unique: 4CZnjbkNNsSlXUHxWAjX5g-1 X-Mimecast-MFC-AGG-ID: 4CZnjbkNNsSlXUHxWAjX5g_1764471401 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id BA2A9195605A; Sun, 30 Nov 2025 02:56:40 +0000 (UTC) Received: from localhost (unknown [10.72.112.6]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 8CF05195608E; Sun, 30 Nov 2025 02:56:38 +0000 (UTC) Date: Sun, 30 Nov 2025 10:56:33 +0800 From: Baoquan He To: Sourabh Jain Cc: akpm@linux-foundation.org, Qiang Ma , kexec@lists.infradead.org, linux-kernel@vger.kernel.org, shivang upadhyay Subject: Re: [PATCH v3 0/3] kexec: print out debugging message if required for kexec_load Message-ID: References: <20251126084427.3222212-1-maqianga@uniontech.com> <7aadda55-d2a4-40f9-95ef-d284ec358646@linux.ibm.com> <77ce0329-1f82-49be-b18a-73c9e5c3e85e@linux.ibm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <77ce0329-1f82-49be-b18a-73c9e5c3e85e@linux.ibm.com> X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 On 11/28/25 at 03:11pm, Sourabh Jain wrote: > Hello Baoquan, > > On 27/11/25 21:00, Baoquan He wrote: > > On 11/27/25 at 05:31pm, Sourabh Jain wrote: > > > Hello All, > > > > > > Do we have plan to support KEXEC_DEBUG flag? > > > > > > Because upstream kexec-tools already added support for KEXEC_DEBUG flag > > > and that breaks the kexec_load with -d option. > > > > > > - kexec: add kexec flag to support debug printing > > > https://git.kernel.org/pub/scm/utils/kernel/kexec/kexec-tools.git/commit/?id=71d6fd99af7e > > I think we should revert that kexec-tools commit. > > Yeah, userspace changes shouldn't go in until the kernel patches are > finalized. It seems that there are disagreements regarding the approach > and usefulness of this patch series, so reverting the kexec-tools patch > might be the right thing to avoid breaking anything for now. The patch 1 is issue fixing, that is a good one. While patch 2, 3 are trying to add debugging printing for kexec_load interface which I think is not needed. I added debugging printing for kexec_file_load because I has been using 'kexec -d' to debug for kexec_load while kexec_file_load didn't have. So I mimicked kexec_load's debugging printing to add one for kexec_file_load. Now patch 2,3's adding doesn't make sense as he said he is doing for future need. > > I have one question: should the kernel advertise KEXEC_DEBUG so that > backward compatibility can be maintained between the kernel and > kexec-tools? Or is that too much for a debugging flag? How was backward > compatibility handled when we added the KEXEC_FILE_DEBUG flag? When I added KEXEC_FILE_DEBUG, I didn't consider backward compatibility. That is making the then latest kernel match the then latest kexec-tools. > > > This whole patchset is > > non-sense. Because of my carelessness, that userspace patch was merged. > > > > Hi Sourabh, > > > > Could you go through this patchset and help check if they are really > > needed? I can't find anything to convince myself. Thanks. > > Sure I will review this patch series. Thanks. Please check patch 2,3 to see if we really need the debugging printing for kexec_load, or its adding really brings benefit even if it's a little bit compared with the mess it brings; and if my objecting is too subjective. Thanks Baoquan