From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 2F3BE3128D7 for ; Fri, 5 Dec 2025 10:41:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764931285; cv=none; b=OAclgVfa4JaPdgZnRFxljLIZvTLewBgRSukoM31lmHsblQtFfTCpZXKutiezJqZfjbJrefjpvuGSLl2OHsxjdzX7q0Lq3ECRxArDe4bCcaoX/wOvLVP1R9yY/Pjsqr4RZqVb9KfPqpQ1JLIp5tuUNMtVlqoZmjfooiGqhRuj1l0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764931285; c=relaxed/simple; bh=eGEZCQZsBwS9cLOuWgdhXzk9ihYwqmTLAjViQWWSdEk=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=HB3MZ7rSIjQiZLBgYXqN6l5zSinPGWEsvQGUcaU3ap7DZaFqSV514bVyKPECIyYmqAtKR7qI1/HGjjh96yoMc8lxDOSgydmu4cG+S4NrvMKtul3shh+HrPb8G6JmnOAAIY1n3ToSgKzcRKExiwtl24ARALdDa2KfCnwrPHCKP04= 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=Gcfvl8UY; arc=none smtp.client-ip=170.10.133.124 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="Gcfvl8UY" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1764931277; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=2hKG0vjiPt1DGx7i+HyDcVcJIkL4pXvQ+G74wXn9PEU=; b=Gcfvl8UYonxWVcjW2PoZJFB7oOthurCP/tNjenJeBgz5gV+ljzGOhrsKiLpDMqxRd6vYRg ZX8x51CL7iiJoUxRZ28NpW5AjWZCN43v8iHP43HnFWNdW7gLu3CKmgNVx9eMHKO96Qo8ku OfgrHoyV/tCsJbScOo6tTMJjzvUUy44= 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-608-F8MVyTFZNSysUgSLUG40cw-1; Fri, 05 Dec 2025 05:41:13 -0500 X-MC-Unique: F8MVyTFZNSysUgSLUG40cw-1 X-Mimecast-MFC-AGG-ID: F8MVyTFZNSysUgSLUG40cw_1764931272 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (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 A0D2A1956052; Fri, 5 Dec 2025 10:41:12 +0000 (UTC) Received: from rotkaeppchen (unknown [10.45.225.39]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 26EB01800357; Fri, 5 Dec 2025 10:41:10 +0000 (UTC) Date: Fri, 5 Dec 2025 11:41:06 +0100 From: Philipp Rudo To: Stephen Brennan Cc: Omar Sandoval , Subject: Re: Unknown ORC entry type 5 on RHEL 9 kernel Message-ID: <20251205114106.07848df1@rotkaeppchen> In-Reply-To: <87h5u6j9k1.fsf@oracle.com> References: <87h5u6j9k1.fsf@oracle.com> Organization: Red Hat inc. Precedence: bulk X-Mailing-List: linux-debuggers@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: O165h0kdmF9S5z92DntR1rVQ0EzXCNQqzzuIDVvOI2c_1764931272 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Hi Stephen, thanks for letting me know. And yes that is something we need to fix in the kernel rather than drgn. I took a quick look and found that the change was included when backporting fb799447ae29 ("x86,objtool: Split UNWIND_HINT_EMPTY in two") for 9.6. Thing is that I'll be heading to LPC tomorrow and won't have time to work on it properly before that... One more hint. When you want to get the history of RHEL, it's better to check the centos-stream repo then the changelog. There you have the full git history (modulo some embargoed CVE fixes). https://gitlab.com/redhat/centos-stream/src/kernel/centos-stream-9 Thanks Philipp On Thu, 04 Dec 2025 12:06:54 -0800 Stephen Brennan wrote: > Hi Philipp, > > I wanted to let you know about an issue with drgn's stack unwinding on > the RHEL 9 kernel. It looks like that kernel backports some ORC changes, > without including a change Omar made (including an .orc_header section) > to help identify the ORC format version. I've included more details on > this drgn issue: > > https://github.com/osandov/drgn/issues/578 > > The result is that drgn can't unwind stacks on the RHEL 9 kernel. I > think the best path forward would be to include the .orc_header patch: > b9f174c811e3a ("x86/unwind/orc: Add ELF section with ORC version identifier") > > As it is, the RHEL 9 drgn can't unwind stacks on the RHEL 9 kernel, > which seems less than ideal. > > Thanks, > Stephen >