From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55])
	(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 9CEDD35AC07
	for <linux-kernel@vger.kernel.org>; Fri, 19 Jun 2026 09:51:30 +0000 (UTC)
Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55
ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116;
	t=1781862693; cv=none; b=SZdzt0stZNcpFuYZW3pe80T384bA/s6ftoo8C+WsEbFW2dOjPKhkf/VjxOHZcx5ch4QmX7z39SSXjAahymN2DHUQSRGwOC10NnxyMh3/QiptqOrJz1zfZz3+uB5JdRK2yI3H2yj6YWRZRlX6yVzk0zWc3ETRWskGmWU/VcKAXDM=
ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org;
	s=arc-20240116; t=1781862693; c=relaxed/simple;
	bh=OroYXirJsDtmCVP7GQcrIX3ogoJcvh8eNLlqMpDtF2c=;
	h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID:
	 MIME-Version:Content-Type; b=b39al0P6DFKTAH7Pw4K9FhbT4fD2YbAgMWI5Fp7d1A1Q4EAlXgvgCm8tq1neSswjuhM91H6sadkGewg3sYhJ0EWdy/7ZmdOl4PghpC1RpP/AnFAMCjLFVG/3Dm5b1xJX031POpLHILKJGBv1swLm2kNJ23CUzWfy6LT5Op/F33E=
ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=tilpw6Yo; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=+wI9V3Mr; arc=none smtp.client-ip=193.142.43.55
Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de
Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de
Authentication-Results: smtp.subspace.kernel.org;
	dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="tilpw6Yo";
	dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="+wI9V3Mr"
From: Nam Cao <namcao@linutronix.de>
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de;
	s=2020; t=1781862688;
	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=WZ1IagdnVV5TSo0RVKP9IMzKUX1buvpUmeHeQfapSPA=;
	b=tilpw6YoUZOSNHkMtcJp95Mc7b4AyNNFqqjoL0ggMK7knjoxriZ7ghkk5KPbC7FanKEWR5
	faZKWOcXZA8ylgLDkx2wCNh6Ke0lkgN/ojq+qGwjGVRi6ADe+5IQkoas1IaRortZg6e/Tj
	+ejdFB0aTNhfXNqGGr+9GxAahX/KVt3l1FjxgBq6h0M/N3Bdd9/GlBma6pSYKPKhhru1+J
	1jPCKH1gRApzE+L0hZBhqz5i9I3/5TPzK8lJoKXxzHDYCJrQu1/uwGHTtJ3HBptaP2Ixx5
	h6Jj5F4L3i9oAwgi8Xr8qnmWdNZdQT4jAvB66tLNtoYAKjkggCfs+cEr7UKVUQ==
DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de;
	s=2020e; t=1781862688;
	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=WZ1IagdnVV5TSo0RVKP9IMzKUX1buvpUmeHeQfapSPA=;
	b=+wI9V3MrwlaBhrA0/QNwdvQtkI9F1r4hmxAOk6jkUp2N+XlJcveUYnY/iGoQfVZZSb4RRw
	4syuW7tr9cF1esBA==
To: Jiakai Xu <xujiakai2025@iscas.ac.cn>, linux-kernel@vger.kernel.org,
 linux-riscv@lists.infradead.org
Cc: Albert Ou <aou@eecs.berkeley.edu>, Alexandre Ghiti <alex@ghiti.fr>,
 Chunyan Zhang <zhangchunyan@iscas.ac.cn>, Jiakai Xu
 <xujiakai2025@iscas.ac.cn>, Matthew Bystrin <dev.mbstr@gmail.com>, Palmer
 Dabbelt <palmer@dabbelt.com>, Paul Walmsley <pjw@kernel.org>, Samuel
 Holland <samuel.holland@sifive.com>
Subject: Re: [PATCH v2] riscv: stacktrace: fix stack-out-of-bounds in
 walk_stackframe()
In-Reply-To: <20260517143704.659416-1-xujiakai2025@iscas.ac.cn>
References: <20260517143704.659416-1-xujiakai2025@iscas.ac.cn>
Date: Fri, 19 Jun 2026 11:51:28 +0200
Message-ID: <87zf0q504f.fsf@yellow.woof>
Precedence: bulk
X-Mailing-List: linux-kernel@vger.kernel.org
List-Id: <linux-kernel.vger.kernel.org>
List-Subscribe: <mailto:linux-kernel+subscribe@vger.kernel.org>
List-Unsubscribe: <mailto:linux-kernel+unsubscribe@vger.kernel.org>
MIME-Version: 1.0
Content-Type: text/plain

Jiakai Xu <xujiakai2025@iscas.ac.cn> writes:
> +	if (!task)
> +		task = current;
> +
> +	high = (unsigned long)task_pt_regs(task);

I am concerned when CONFIG_IRQ_STACKS=y and we are on the irq stack,
wouldn't this "high" be the wrong one?

I haven't validated it, we probably need something like

if (on_thread_stack()) {
	if (!task)
        	task = current;
	high = (unsigned long)task_pt_regs(task);
} else {
	high = per_cpu(irq_stack_ptr, smp_processor_id()) + IRQ_STACK_SIZE/sizeof(ulong);
}

Nam