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References: <20240220060718.823229-1-apatel@ventanamicro.com>
 <20240220060718.823229-3-apatel@ventanamicro.com> <87frxnigxk.ffs@tglx>
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From: Anup Patel <apatel@ventanamicro.com>
Date: Wed, 21 Feb 2024 19:05:52 +0530
Message-ID: <CAK9=C2VFksO054kVVHkrBRyZqte8Q4Gpup97VhLBRDCbOyQdqQ@mail.gmail.com>
Subject: Re: [PATCH v13 02/13] irqchip/sifive-plic: Improve locking safety by
 using irqsave/irqrestore
To: Thomas Gleixner <tglx@linutronix.de>
Cc: Palmer Dabbelt <palmer@dabbelt.com>, Paul Walmsley <paul.walmsley@sifive.com>, 
	Rob Herring <robh+dt@kernel.org>, 
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>, Frank Rowand <frowand.list@gmail.com>, 
	Conor Dooley <conor+dt@kernel.org>, Marc Zyngier <maz@kernel.org>, =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= <bjorn@kernel.org>, 
	Atish Patra <atishp@atishpatra.org>, Andrew Jones <ajones@ventanamicro.com>, 
	Sunil V L <sunilvl@ventanamicro.com>, Saravana Kannan <saravanak@google.com>, 
	Anup Patel <anup@brainfault.org>, linux-riscv@lists.infradead.org, 
	linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, 
	devicetree@vger.kernel.org
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On Tue, Feb 20, 2024 at 3:41=E2=80=AFPM Thomas Gleixner <tglx@linutronix.de=
> wrote:
>
> On Tue, Feb 20 2024 at 11:37, Anup Patel wrote:
> > Now that PLIC driver is probed as a regular platform driver, the lock
> > dependency validator complains about the safety of handler->enable_lock
> > usage:
> >
> > [    0.956775]  Possible interrupt unsafe locking scenario:
> >
> > [    0.956998]        CPU0                    CPU1
> > [    0.957247]        ----                    ----
> > [    0.957439]   lock(&handler->enable_lock);
> > [    0.957607]                                local_irq_disable();
> > [    0.957793]                                lock(&irq_desc_lock_class=
);
> > [    0.958021]                                lock(&handler->enable_loc=
k);
> > [    0.958246]   <Interrupt>
> > [    0.958342]     lock(&irq_desc_lock_class);
> > [    0.958501]
> >                 *** DEADLOCK ***
> >
> > To address above, let's use raw_spin_lock_irqsave/unlock_irqrestore()
> > instead of raw_spin_lock/unlock().
>
> s/let's//

Okay, I will update.

Regards,
Anup