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 993E732ABCD for ; Mon, 2 Mar 2026 10:33:23 +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=1772447604; cv=none; b=ObeGdhpDJmxhZ3vsYl6LEt5EqYkXKEc+cj7gGnlCNACfP2tWSMv12LDrP0LLssAvr/fGSXLMWMj4O/C7iKaqmfOM02VO/otnp5MgUecssA5gupYtcKXmQ/MofGR1mxOGmi1QL5OYWUTezKWXgWEzaJs4+yJ4C+0YzGv3VOKCu58= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772447604; c=relaxed/simple; bh=MbSOzDEm2OmCgL9BjGpViMtZsmeutFPVslXiuoycP88=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=plqF+6fqMAfehh5A7obhGnTMXq2P6SoA9FfBvdIPVb69d9KpkKFai6A179irfBsqOdJMzCmnOPSI4dRW9CTl7ETBY9U6LJ6oEAzcNwZZz3SdkjDU9bPeeDl7bA/+qzJvO+bQUPy3/07BfHe0JejW6o8Kk4ufNLjgdZ7Ws3bxIK0= 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=agDuY6VS; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=qLfEhmvn; 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="agDuY6VS"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="qLfEhmvn" Date: Mon, 2 Mar 2026 11:33:19 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1772447601; 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=3zpCsC76A/B8FEp6NQth+KPKVyK8PduJ80CXc9DihGY=; b=agDuY6VSHjOEVidIw9tmeJdXttkw0fiS17n6SGkI/4sKaOdW3x451mWnod8UdVEJ8Q4wky LqAV/voYBIHtT1nF+GjG4Tfldk5ScLL/XWqJjtBZD78+E1EhqJF50N5uP8kyIyXrPKc+14 kBdAPp2MzMWtUDbwyQWyg7PvKWGgTMALIMZO5oJKYqsFmUL+yMR6FKKFtjara5awUReslW 4IcE6aDrrGdKdEFrUVLA/jWNwYW7JgDn9OPx/Smbi1UwV+9QsKeLGviv5ThJdxjZCACznX M8WRXzoyT2Ii9b69DQRsHciEGEjW5kQCLq95P6o/gEy6wpe2ZUh/hX0+wJk2hw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1772447601; 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=3zpCsC76A/B8FEp6NQth+KPKVyK8PduJ80CXc9DihGY=; b=qLfEhmvnxGcsNliQohntBn3K6GLY3gY5LOFdBG1n0YwuyoOzlDQYN4lsWFmAV2BlNpy+m3 i4YMjG1POEhtljBQ== From: Sebastian Andrzej Siewior To: "Russell King (Oracle)" Cc: linux-arm-kernel@lists.infradead.org, Clark Williams , linux-rt-devel@lists.linux.dev, Steven Rostedt Subject: Re: [PATCH 1/6] ARM: ensure interrupts are enabled in __do_user_fault() Message-ID: <20260302103319.VI_GSa_5@linutronix.de> References: Precedence: bulk X-Mailing-List: linux-rt-devel@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: On 2026-02-27 15:19:08 [+0000], Russell King (Oracle) wrote: > __do_user_fault() may be called from fault handling paths where the > interrupts are enabled or disabled. E.g. do_page_fault() calls this > with interrupts enabled, whereas do_sect_fault()->do_bad_area() > will call this with interrupts disabled. Since this is a userspace > fault, we know that interrupts were enabled in the parent context, > so call local_irq_enable() here to give a consistent interrupt state. > > This is necessary for force_sig_info() when PREEMPT_RT is enabled. Reported-by: Yadi.hu > Signed-off-by: Russell King (Oracle) > --- > arch/arm/mm/fault.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c > index ed4330cc3f4e..6c27ebd49093 100644 > --- a/arch/arm/mm/fault.c > +++ b/arch/arm/mm/fault.c > @@ -190,7 +190,8 @@ __do_kernel_fault(struct mm_struct *mm, unsigned long addr, unsigned int fsr, > > /* > * Something tried to access memory that isn't in our memory map.. > - * User mode accesses just cause a SIGSEGV > + * User mode accesses just cause a SIGSEGV. Ensure interrupts are enabled > + * for preempt RT. PREEMPT_RT. > */ > static void > __do_user_fault(unsigned long addr, unsigned int fsr, unsigned int sig, Sebastian