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 4062C2D12EC
	for <linux-kernel@vger.kernel.org>; Sat, 27 Jun 2026 11:59:13 +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=1782561554; cv=none; b=bO/rZt+f032195YG0W2VivLQNLxLnt2et3p5tXOnMhVqlgngXsEFmw1Cq/7Dpa9hXrcrMXEK/qixlk3yoSjLlbfuad++BJtXKDMlhs3JhdcwF01VVnW/X9SFeU3dCtYbt6jiZs5xbAovv/pdMwWFD1mDpocXF3MH2c+YfIaKDHw=
ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org;
	s=arc-20240116; t=1782561554; c=relaxed/simple;
	bh=Rj7gHHEaq1OZXfvrq1PJAw7w4i0DrksirWQawAb0e2E=;
	h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID:
	 MIME-Version:Content-Type; b=AbK7fUfSfjq3APGq6hGes+S77qUpSw15KXxNfYuduwNDi9ubXcuUaNSTfo9mSB0uM+Fa/EwHzrOc1khXUGSHur/surcKwWdcsECnINxLARF55MORXGPw0AXpGMBtO//yV68m2JucNUFzxRQhgP+G9p/EHgDt/9qsJh+VgFXN7TU=
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=OJ2v7Saq; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=Din2LXd2; 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="OJ2v7Saq";
	dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="Din2LXd2"
From: Nam Cao <namcao@linutronix.de>
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de;
	s=2020; t=1782561551;
	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=zz7muMR2y2m8wMPeJd2fbbBgpyba86ouaGupG4x7Onk=;
	b=OJ2v7SaqZ6p2uQKb1KB3sYtEkpDTUm1oJafzGknXxUnJmAU2jmE4dqxftkD5jQG9A1NYE0
	LBexswRK7hivG/cQiCp8c3hLpKbcsDQYAPEghSu54+Pb2+gHmDA+J1yWUWWDgmZ+fn/o9o
	tS3m38Sh+2sLlF+PR9RpnSvsyfBR4/M+BIyZ0GqGELWJTOb7QrOx80V/ao20wrzflvClDv
	562ptRRpSBRNkq+ZvwBNhTbN1q6RDFEZjypO9ii/LFNtvDdqmfpcRSmQM1IocBgg2pyXUi
	q5vqCDxK8Q4p9+Bkm+zGfMDIVEg0cEuGJyNbFiVro3+StiF3HNi1ITdqA4VkpQ==
DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de;
	s=2020e; t=1782561551;
	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=zz7muMR2y2m8wMPeJd2fbbBgpyba86ouaGupG4x7Onk=;
	b=Din2LXd2lP45ltmSDRBkHblVW/HV823P+Pjn02dHUm/biMea0ZXle2IbTV3ECorgBK7zGc
	k0ZQMWGDG4hgJdBg==
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>, Rui Qi
 <qirui.001@bytedance.com>, Samuel Holland <samuel.holland@sifive.com>,
 Jiakai Xu <jiakaiPeanut@gmail.com>
Subject: Re: [PATCH v3] riscv: stacktrace: fix stack-out-of-bounds in
 walk_stackframe()
In-Reply-To: <20260625123906.211981-1-xujiakai2025@iscas.ac.cn>
References: <20260625123906.211981-1-xujiakai2025@iscas.ac.cn>
Date: Sat, 27 Jun 2026 13:59:10 +0200
Message-ID: <87zf0g42k1.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:
> +#ifdef CONFIG_IRQ_STACKS
> +DECLARE_PER_CPU(ulong *, irq_stack_ptr);
> +#endif

Instead of this, shouldn't we
  #include <asm/irq_stack.h>
?

> +	if (sp >= (unsigned long)task_stack_page(task) &&
> +	    sp < (unsigned long)task_stack_page(task) + THREAD_SIZE) {
> +		high = (unsigned long)task_pt_regs(task);
> +	} else if (IS_ENABLED(CONFIG_IRQ_STACKS)) {
> +		high = (unsigned long)this_cpu_read(irq_stack_ptr) +
> +		       IRQ_STACK_SIZE;

I suspect this fails to build if CONFIG_IRQ_STACKS=n, which would be
resolved if we do the suggested #include above.

> +	} else {
> +		high = (unsigned long)task_pt_regs(task);

We only get to this branch if the stack pointer is broken, right? If so,
I think printing a warning and returning is more appropriate.

Nam