From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 103DBE9B342 for ; Mon, 2 Mar 2026 10:33:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id: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-Owner; bh=3zpCsC76A/B8FEp6NQth+KPKVyK8PduJ80CXc9DihGY=; b=H0bJ48KSQ1kh1f/3N2QwzkKf6c WIuqQTuSf6JHfarQlbmDizQC5TVTIzqQsjPMk7L6cua+s3TC/P7FSCZdoZGsUu1NlqsdsaqPBainj bKdvi9Hai/vZ1weFlQMhme22Xa7+WdjVQ8waWAwi0pw1dHT7mDdIUZ1DVdKJUrcRTZG3zuspggNEt Sh3RSd+OLvyn1h4Q5GL3kzZewNZL+7tfjME8Ek3XkjwP64n2XK3vQUvP1R1y5gZ9q3onkixuTcCm1 kHZM1lbwufFd4CzMOIKiJtfhdu/0q7uJTlrM/P+8ElXqQMGPY7ISQ33BGllhuaLBOGM+nRzueS7en ZNp+lWQw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vx0at-0000000CiXJ-1Z3K; Mon, 02 Mar 2026 10:33:43 +0000 Received: from galois.linutronix.de ([2a0a:51c0:0:12e:550::1]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vx0aq-0000000CiWG-2dJ9 for linux-arm-kernel@lists.infradead.org; Mon, 02 Mar 2026 10:33:41 +0000 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: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260302_023340_935433_F4223282 X-CRM114-Status: GOOD ( 16.45 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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