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From:   Andy Lutomirski <luto@amacapital.net>
Date:   Tue, 25 Feb 2020 21:13:36 -0800
Message-ID: <CALCETrVEvz4njpOy-qF8_pHAMKCgp6oDqk8E1CzM-TeAd1br3Q@mail.gmail.com>
Subject: Re: [patch 01/15] x86/irq: Convey vector as argument and not in ptregs
To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     LKML <linux-kernel@vger.kernel.org>, X86 ML <x86@kernel.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Brian Gerst <brgerst@gmail.com>,
        Juergen Gross <jgross@suse.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Arnd Bergmann <arnd@arndb.de>
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On Tue, Feb 25, 2020 at 3:26 PM Thomas Gleixner <tglx@linutronix.de> wrote:
>
> Device interrupts which go through do_IRQ() or the spurious interrupt
> handler have their separate entry code on 64 bit for no good reason.
>
> Both 32 and 64 bit transport the vector number through ORIG_[RE]AX in
> pt_regs. Further the vector number is forced to fit into an u8 and is
> complemented and offset by 0x80 for historical reasons.
>
> Push the vector number into the error code slot instead and hand the plain
> vector number to the C functions.

Reviewed-by: Andy Lutomirski <luto@kernel.org>