From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [78.32.30.218]) (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 B3E353BD641 for ; Fri, 24 Apr 2026 12:21:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=78.32.30.218 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777033317; cv=none; b=lpxena9TmkwzXUNNXCX+A9RsSJcfwI+lKqeJa2x2uEnkuBHT8yBdlL72vtpSzGnUGUL9hrG5KJOHBdSn5D46am5VdqdYCwoxiaQbG/UUWdB7biKpxuQO7RjMvivW3x+J6xZ/YDjsjLyLoBCwCR1ISibQZGLQFGmt5oM67ftMe1s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777033317; c=relaxed/simple; bh=4N+q5LtLtacAr1bYBA7Iw/PoElyL3xCH5rpJtzulfgc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=KIc4ifPrq/s1xdvniCs022YkOqrpID4ARNsOz6K/0aMkqSrPKd61HgQx1jeMVehW5EDv8mnPmynMtzn1OSZkAeyUFHeZbPza8r3n5f9EXeRaUkMQPmWfwgCZF2NQvP9o1v0xMogAH/4sDGOIN0Qh8hKqCvudH+2gqDmSutEB7gI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=armlinux.org.uk; spf=none smtp.mailfrom=armlinux.org.uk; dkim=pass (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b=h1b50Q8P; arc=none smtp.client-ip=78.32.30.218 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=armlinux.org.uk Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=armlinux.org.uk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b="h1b50Q8P" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=Rc7qdqKLMXxIfh21Cj8Dl8AVMepmlB0Fv8KgJ5hmvnU=; b=h1b50Q8PW0ReBCtuZX5A4AsCra CM5IRJK+L8oh2qAmLsB8oD3qKc8vo4cAriH8yXOByV9cB1QCVwLsdEjDGeeIbMzdG59PVn1XSkwDM XD8GISvSMv/pvxFED9j3dPtxvcfViwc8IqQo+QyCRzheMHSJh9YznE/dMz858x1effMhxOs17EMvb GPogOtMCIH+n3mMICIfHC8BHkOODUEJ/pMTTWhDRFicu1w2pfbSERJoyRwDfJOAezncfxN+YksmRT 81ckclJi8YjUAHVE2Mrj1rAxCSccgtgkJt/FHR6CoCOfNR9xE2SJhCglK6J95TYxfqqFMZaF5LtT7 BvUEBxDw==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:48656) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1wGFXR-000000003FY-2I2c; Fri, 24 Apr 2026 13:21:41 +0100 Received: from linux by shell.armlinux.org.uk with local (Exim 4.98.2) (envelope-from ) id 1wGFXO-000000002WO-3Wvf; Fri, 24 Apr 2026 13:21:38 +0100 Date: Fri, 24 Apr 2026 13:21:38 +0100 From: "Russell King (Oracle)" To: Maninder Singh Cc: linus.walleij@linaro.org, ardb@kernel.org, ndesaulniers@google.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/1] arm: traps: remove fp underflow checking Message-ID: References: <20260424043029.4101133-1-maninder1.s@samsung.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: <20260424043029.4101133-1-maninder1.s@samsung.com> Sender: Russell King (Oracle) On Fri, Apr 24, 2026 at 10:00:29AM +0530, Maninder Singh wrote: > with IRQSTACKS fp can point outside of thread's stack. > And when there is crash reported from IRQ side, it always report > "frame pointer underflow", which is not real underflow. > > Unhandled fault: page domain fault (0x81b) at 0x00000000 > .. > PC is at handle_irq_desc+0x68/0xa4 > LR is at generic_handle_domain_irq+0x18/0x1c > .. > > Call trace: frame pointer underflow > handle_irq_desc from generic_handle_domain_irq+0x18/0x1c > generic_handle_domain_irq from gic_handle_irq+0x78/0x8c > gic_handle_irq from generic_handle_arch_irq+0x3c/0x4c > .. > > It is just warning print and there is no decision based on this > to stop backtrack or etc. So it can be removed. Please find a way to check whether the frame pointer is within the IRQ stack rather than removing this. Thanks. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!