From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 8EFD3274B40 for ; Tue, 2 Dec 2025 16:20:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764692427; cv=none; b=F5x2F4SH0r6R2B5mtxYZz1B9lFeGzX2TGQY6bUC8Zs8zTqdWZGnh+5hzcH2VkH6Q4I0p8GAeMCWzrRySENqaQUim4WZaIgk2NW+LW3P1Nmom4t0g6jfW2dQd5QFPcsQV/S6UbKY1sY+xh29QQdLtcksckJOSkSMHog0XTC3xCv4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764692427; c=relaxed/simple; bh=YwYSpdJsvBjrI+KXzrli867ahDD2XLjKd5WpGZI0Y9Y=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=KyVFW2X3KQUdidIMYEgYoBmGBS/yOLdMssf/8o1pvqTsTrWOYJ+IlRzn2ljFOvR4yDCak1DK8ewSdm2T/7rxz3ryfs6wOUILdxSWH4XhAalIlLwZjaFPlMX8Ft/HG5w/5B0Sj1L7MQDdIQgbpxLxx04SYqR6EGgPOjQeYxeXpCo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=AfrV1Wqe; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="AfrV1Wqe" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 53E80C4CEF1; Tue, 2 Dec 2025 16:20:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1764692427; bh=YwYSpdJsvBjrI+KXzrli867ahDD2XLjKd5WpGZI0Y9Y=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=AfrV1WqegbaBSFl0M8Fwa9n1lFq0aQ0VAfi7gShrSWup+VcgiDkjLuvJOATH+tXnT OgB2wlr4qrxBY5CRwjujw2QYp/dRz8whxOyG/uld7aGJcixxBEEdWTtU3CBqPtAQLV jet0BEnfCcmlKCa8DRobT9/HYGRHGgBDl8/n/ZReRf/0nkkiDB3ug0l/rVy+XqYfS2 fDfOeTfLmE2+0e7NsxcvWjBLyPi7M3TO5MH34a+aKK2EF9FZBV93APmxi0AgIVFLsl bRxoKZFL46q04vBX7srJEAgONk6oXrdpVEMJN+cfZGrvL9sV0BCi6YOdlrA5mfLjj0 zGf4yR7eQY/jg== Date: Tue, 2 Dec 2025 17:20:22 +0100 From: Ingo Molnar To: Josh Poimboeuf Cc: x86@kernel.org, linux-kernel@vger.kernel.org, Nathan Chancellor , Peter Zijlstra , Alexandre Chartre , David Laight Subject: Re: [PATCH] objtool: Fix stack overflow in validate_branch() Message-ID: References: <21bb161c23ca0d8c942a960505c0d327ca2dc7dc.1764691895.git.jpoimboe@kernel.org> 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: <21bb161c23ca0d8c942a960505c0d327ca2dc7dc.1764691895.git.jpoimboe@kernel.org> * Josh Poimboeuf wrote: > On an allmodconfig kernel compiled with Clang, objtool is segfaulting in > drivers/scsi/qla2xxx/qla2xxx.o due to a stack overflow in > validate_branch(). > > Due in part to KASAN being enabled, the qla2xxx code has a large number > of conditional jumps, causing objtool to go quite deep in its recursion. > > By far the biggest offender of stack usage is the recently added > 'prev_state' stack variable in validate_insn(), coming in at 328 bytes. That's weird - how can a user-space tool run into stack limits, are they set particularly conservatively? In any case, applied to tip:objtool/urgent, thanks! Ingo