Re: [PATCH -v2 4/6] x86, RAS: Add function enabling direct writes to MCE MSRs

[Joe Perches <joe@perches.com>]

On Tue, 2012-10-16 at 16:52 +0200, Borislav Petkov wrote:
> From: Borislav Petkov <borislav.petkov@amd.com>
> 
> Normally, writing to MCE MSRs causes a #GP. Add a function to enable
> direct accesses to those MSRs.
[]
> diff --git a/arch/x86/ras/amd/mce-inject.c b/arch/x86/ras/amd/mce-inject.c

> @@ -55,6 +55,30 @@ DEFINE_SIMPLE_ATTRIBUTE(misc_fops, inj_misc_get, inj_misc_set, "%llx\n");
[]
> +static int toggle_hw_mce_inject(unsigned int cpu, bool enable)
[]
> +	enable ? (l |= BIT(18)) : (l &= ~BIT(18));

This is very unusual style.
I found just one like it in the kernel tree.
(unnecessary parens here too btw)

This style is much more common:
	if (enable)
		l |= BIT(18);
	else
		l &= ~BIT(18);