From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 AE8E237472F for ; Wed, 10 Jun 2026 06:51:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781074271; cv=none; b=P/FOy7+x9NGC0eESb5rXjNLQl/RgVNbUweP4bm1ojtiVjpTVV6Ow1xe5bfahCLBLkfJLYXGISUEBQuC0uC1sJx6FwylEPdcGVmFyA4z37cCwFhkWXnNuPFOamQ+PcJnH/okGLc3xs9GU0RLRTLU1xQZzP+aPD8mpf5GNTTMVL94= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781074271; c=relaxed/simple; bh=gKMY/NNkn2/NKh+USTA2Z79d9LxBLdFbGsWIxR12y2E=; h=Date:Message-ID:From:To:Cc:Subject:In-Reply-To:References: MIME-Version:Content-Type; b=FVyZqfPKEEMD9dGVBoLTk8JWchw9x7TS6wDDg5XC8i3u6NNBumcIWgwTPFxhxbVvIf1TxoAy8b2B4nNkxLZGZ3QONMj2j2Ug2Y/nwwKU/VZQBvCPjI55XLYe9XIydV5rcyl7K4rZsSkd+vwLhk7/L9g4AVloZwOCnP8ZO/CPSVI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=nXRYfvqS; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="nXRYfvqS" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 49B0C1F00893; Wed, 10 Jun 2026 06:51:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1781074270; bh=SKlXmaxmQtVvG0/U080qFDWMPwk+dtQPthuSsH4n1ZE=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=nXRYfvqSDlwTMylUZ1xeIygMycU6G5mg+2cd48HzqxQplPi3RG6TvOd6x9DcsxAyP d8l8TzoR5qm1zjgRDp2U9p+l5fYC9qHHC9P8vsnYjshhzRt7fQSXYuZnVjU5XAAFPx VdZSadiK9hJyuGm/zks2FrKTdL92P//ZY1izTjiWr3/Wx8llVK0xJmyZ15Fs1phJfO ioINyxXniMAqVabveB4ZJMVYTU3PCzz6XDmf2CwRumwP0FTDFEdnkkIL34jfOuJ87g nN5+bnnd/IgkLr/l1Sxa9+BCdv/CVsUQRVSHoGEMkNrts1i5xMoz53VbYCtWbe502T 6RzvunXjFU8bA== Received: from sofa.misterjones.org ([185.219.108.64] helo=goblin-girl.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1wXCmJ-0000000BDkg-3U2J; Wed, 10 Jun 2026 06:51:07 +0000 Date: Wed, 10 Jun 2026 07:51:07 +0100 Message-ID: <86bjdiubvo.wl-maz@kernel.org> From: Marc Zyngier To: Bhargav Joshi Cc: Thomas Gleixner , Tony Lindgren , Jason Cooper , linux-kernel@vger.kernel.org, goledhruva@gmail.com, m-chawdhry@ti.com, daniel.baluta@gmail.com, simona.toaca@nxp.com Subject: Re: [PATCH RFC] irqchip: crossbar: Fix data race in allocate_gic_irq In-Reply-To: <20260610-irq-spinlock-fix-v1-1-6f227ea9fa34@gmail.com> References: <20260610-irq-spinlock-fix-v1-1-6f227ea9fa34@gmail.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/30.1 (aarch64-unknown-linux-gnu) MULE/6.0 (HANACHIRUSATO) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: j.bhargav.u@gmail.com, tglx@kernel.org, tony@atomide.com, jason@lakedaemon.net, linux-kernel@vger.kernel.org, goledhruva@gmail.com, m-chawdhry@ti.com, daniel.baluta@gmail.com, simona.toaca@nxp.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false On Tue, 09 Jun 2026 22:00:09 +0100, Bhargav Joshi wrote: > > In allocate_gic_irq(), if irq_domain_alloc_irqs_parent() fails, the > error path resets cb->irq_map[i] to IRQ_FREE. It modifies cb->irq_map[] > without holding cb->lock. modifying without lock could cause data race. > > Fix this by acquiring raw_spin_lock around cb->irq_map[] modification. > > Fixes: 783d31863fb8 ("irqchip: crossbar: Convert dra7 crossbar to stacked domains") > > Signed-off-by: Bhargav Joshi > --- > This bug was flagged by the Sashiko AI bot during the review process for > the DT schema conversion of ti,irq-crossbar binding. > https://lore.kernel.org/linux-devicetree/20260605210647.CCC881F00893@smtp.kernel.org/ > --- > drivers/irqchip/irq-crossbar.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/irqchip/irq-crossbar.c b/drivers/irqchip/irq-crossbar.c > index cd1134101ace..9b809e711009 100644 > --- a/drivers/irqchip/irq-crossbar.c > +++ b/drivers/irqchip/irq-crossbar.c > @@ -100,8 +100,11 @@ static int allocate_gic_irq(struct irq_domain *domain, unsigned virq, > fwspec.param[2] = IRQ_TYPE_LEVEL_HIGH; > > err = irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec); > - if (err) > + if (err) { > + raw_spin_lock(&cb->lock); > cb->irq_map[i] = IRQ_FREE; > + raw_spin_lock(&cb->lock); Really? M. -- Without deviation from the norm, progress is not possible.