linux-kernel - RE: [PATCH 3/4] irqchip/sifive-plic: Separate irq

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <DM6PR04MB62010CC19FEAEE738F2BC00E8DB80@DM6PR04MB6201.namprd04.prod.outlook.com>
Date:   Mon, 18 May 2020 09:00:51 +0000
From:   Anup Patel <Anup.Patel@....com>
To:     Marc Zyngier <maz@...nel.org>
CC:     Palmer Dabbelt <palmer@...belt.com>,
        Paul Walmsley <paul.walmsley@...ive.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Jason Cooper <jason@...edaemon.net>,
        Atish Patra <Atish.Patra@....com>,
        Alistair Francis <Alistair.Francis@....com>,
        Anup Patel <anup@...infault.org>,
        "linux-riscv@...ts.infradead.org" <linux-riscv@...ts.infradead.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: RE: [PATCH 3/4] irqchip/sifive-plic: Separate irq_chip for muiltiple
 PLIC instances



> -----Original Message-----
> From: Marc Zyngier <maz@...nel.org>
> Sent: 18 May 2020 13:45
> To: Anup Patel <Anup.Patel@....com>
> Cc: Palmer Dabbelt <palmer@...belt.com>; Paul Walmsley
> <paul.walmsley@...ive.com>; Thomas Gleixner <tglx@...utronix.de>; Jason
> Cooper <jason@...edaemon.net>; Atish Patra <Atish.Patra@....com>; Alistair
> Francis <Alistair.Francis@....com>; Anup Patel <anup@...infault.org>; linux-
> riscv@...ts.infradead.org; linux-kernel@...r.kernel.org
> Subject: Re: [PATCH 3/4] irqchip/sifive-plic: Separate irq_chip for muiltiple PLIC
> instances
> 
> On 2020-05-16 17:38, Anup Patel wrote:
> >> -----Original Message-----
> >> From: Marc Zyngier <maz@...nel.org>
> 
> [...]
> 
> >> I *have* given you a way to implement that in a better way. But
> >> again, I'd rather you *don't* do it for the reason I have outlined
> >> above.
> >
> > I explored kernel/irq/proc.c and we can achieve what this patch does
> > by implementing irq_print_chip() callback of "struct irq_chip" so we
> > certainly don't need separate "struct irq_chip" for each PLIC instance.
> >
> > I will implement irq_print_chip() callback in v2 series.
> 
> You still haven't explained *why* you need to have this change.
> As it stands, I'm not prepared to take it.
> 

This is only for differentiating interrupts of multiple PLIC instance
In /proc/interrupts.

I will drop this patch since (like you mentioned) contents of
/proc/interrupts is considered an ABI and this patch breaks it.

For now, we can infer the PLIC instance for interrupt X based
on contents of /proc/irq/X/node (i.e. interrupt NUMA node id).

Thanks,
Anup