linux-kernel - Re: [PATCH 11/12] efi/libstub: arm/arm64: Disable debug prints on 'quiet' cmdline arg

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Date:   Tue, 11 Apr 2017 00:08:39 -0400
From:   Jon Masters <jcm@...masters.org>
To:     Ard Biesheuvel <ard.biesheuvel@...aro.org>,
        linux-efi@...r.kernel.org, Ingo Molnar <mingo@...nel.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        "H . Peter Anvin" <hpa@...or.com>
Cc:     matt@...eblueprint.co.uk, mark.rutland@....com,
        roy.franz@...ium.com, rruigrok@...eaurora.org,
        leif.lindholm@...aro.org, jhugo@...eaurora.org,
        evgeny.kalugin@...el.com, eugene@...com, bp@...en8.de,
        bhsharma@...hat.com, bhe@...hat.com, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 11/12] efi/libstub: arm/arm64: Disable debug prints on
 'quiet' cmdline arg

On 04/04/2017 12:09 PM, Ard Biesheuvel wrote:
> The EFI stub currently prints a number of diagnostic messages that do
> not carry a lot of information. Since these prints are not controlled
> by 'loglevel' or other command line parameters, and since they appear on
> the EFI framebuffer as well (if enabled), it would be nice if we could
> turn them off.
> 
> So let's add support for the 'quiet' command line parameter in the stub,
> and disable the non-error prints if it is passed.

> +extern int __pure is_quiet(void);
> +
> +#define pr_efi(sys_table, msg)		do {				\
> +	if (!is_quiet()) efi_printk(sys_table, "EFI stub: "msg);	\
> +} while (0)
> +
> +#define pr_efi_err(sys_table, msg) efi_printk(sys_table, "EFI stub: ERROR: "msg)

Thanks for this one :)

Jon.