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Date:   Sun, 24 Jan 2021 19:01:48 +0000
Message-ID: <87r1majh0j.wl-maz@kernel.org>
From:   Marc Zyngier <maz@kernel.org>
To:     David Brazdil <dbrazdil@google.com>
Cc:     linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu,
        linux-kernel@vger.kernel.org,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Alexandru Elisei <alexandru.elisei@arm.com>,
        Ard Biesheuvel <ardb@kernel.org>,
        Jing Zhang <jingzhangos@google.com>,
        Ajay Patil <pajay@qti.qualcomm.com>,
        Prasad Sodagudi <psodagud@codeaurora.org>,
        Srinivas Ramana <sramana@codeaurora.org>,
        James Morse <james.morse@arm.com>,
        Julien Thierry <julien.thierry.kdev@gmail.com>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        kernel-team@android.com
Subject: Re: [PATCH v4 15/21] arm64: Add an aliasing facility for the idreg override
In-Reply-To: <20210118131839.7ao33jeufq3dfnb4@google.com>
References: <20210118094533.2874082-1-maz@kernel.org>
        <20210118094533.2874082-16-maz@kernel.org>
        <20210118131839.7ao33jeufq3dfnb4@google.com>
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On Mon, 18 Jan 2021 13:18:39 +0000,
David Brazdil <dbrazdil@google.com> wrote:
> 
> On Mon, Jan 18, 2021 at 09:45:27AM +0000, Marc Zyngier wrote:
> > In order to map the override of idregs to options that a user
> > can easily understand, let's introduce yet another option
> > array, which maps an option to the corresponding idreg options.
> > 
> > Signed-off-by: Marc Zyngier <maz@kernel.org>
> Acked-by: David Brazdil <dbrazdil@google.com>
> 
> > ---
> >  arch/arm64/kernel/idreg-override.c | 20 ++++++++++++++++++++
> >  1 file changed, 20 insertions(+)
> > 
> > diff --git a/arch/arm64/kernel/idreg-override.c b/arch/arm64/kernel/idreg-override.c
> > index 75d9845f489b..16bc8b3b93ae 100644
> > --- a/arch/arm64/kernel/idreg-override.c
> > +++ b/arch/arm64/kernel/idreg-override.c
> > @@ -37,6 +37,12 @@ static const struct reg_desc * const regs[] __initdata = {
> >  	&mmfr1,
> >  };
> >  
> > +static const struct {
> > +	const char * const	alias;
> > +	const char * const	feature;
> > +} aliases[] __initdata = {
> > +};
> > +
> >  static int __init find_field(const char *cmdline, const struct reg_desc *reg,
> >  			     int f, u64 *v)
> >  {
> > @@ -80,6 +86,18 @@ static void __init match_options(const char *cmdline)
> >  	}
> >  }
> >  
> > +static __init void match_aliases(const char *cmdline)
> > +{
> > +	int i;
> > +
> > +	for (i = 0; i < ARRAY_SIZE(aliases); i++) {
> > +		char *str = strstr(cmdline, aliases[i].alias);
> > +
> > +		if ((str == cmdline || (str > cmdline && *(str - 1) == ' ')))
> 
> nit: Extract to a 'cmdline_contains' helper? Took me a good few seconds to
> parse this in the previous patch. Giving it a name would help, and now it's
> also shared.

Good point. Adopted!

Thanks,

	M.

-- 
Without deviation from the norm, progress is not possible.