From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH v4 15/17] x86/traps: Fixup general protection faults
 caused by UMIP
Date: Thu, 23 Feb 2017 10:27:24 +0100
Message-ID: <20170223092724.GZ6515@twins.programming.kicks-ass.net>
References: <20170223063706.71554-1-ricardo.neri-calderon@linux.intel.com>
 <20170223063706.71554-16-ricardo.neri-calderon@linux.intel.com>
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To: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>, Thomas Gleixner <tglx@linutronix.de>, "H. Peter Anvin" <hpa@zytor.com>, Andy Lutomirski <luto@kernel.org>, Borislav Petkov <bp@suse.de>, Andrew Morton <akpm@linux-foundation.org>, Brian Gerst <brgerst@gmail.com>, Chris Metcalf <cmetcalf@mellanox.com>, Dave Hansen <dave.hansen@linux.intel.com>, Paolo Bonzini <pbonzini@redhat.com>, Liang Z Li <liang.z.li@intel.com>, Masami Hiramatsu <mhiramat@kernel.org>, Huang Rui <ray.huang@amd.com>, Jiri Slaby <jslaby@suse.cz>, Jonathan Corbet <corbet@lwn.net>, "Michael S. Tsirkin" <mst@redhat.com>, Paul Gortmaker <paul.gortmaker@windriver.com>, Vlastimil Babka <vbabka@suse.cz>, Chen Yucong <slaoub@gmail.com>, Alexandre Julliard <julliard@winehq.org>, Stas Sergeev <sts>

On Wed, Feb 22, 2017 at 10:37:04PM -0800, Ricardo Neri wrote:
> @@ -492,6 +493,9 @@ do_general_protection(struct pt_regs *regs, long error_code)
>  	RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
>  	cond_local_irq_enable(regs);
>  
> +	if (user_mode(regs) && (fixup_umip_exception(regs) == true))
> +		return;

I'm thinking

	if (user_mode(regs) && fixup_umip_exception(regs))
		return;

is actually easier to read.