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Date:   Mon, 13 May 2019 15:50:56 +0200
From:   Radim =?utf-8?B?S3LEjW3DocWZ?= <rkrcmar@redhat.com>
To:     Nadav Amit <nadav.amit@gmail.com>
Cc:     Paolo Bonzini <pbonzini@redhat.com>, kvm@vger.kernel.org
Subject: Re: [PATCH] x86: Halt on exit
Message-ID: <20190513135055.GA8697@flask>
References: <20190509195023.11933-1-nadav.amit@gmail.com>
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2019-05-09 12:50-0700, Nadav Amit:
> In some cases, shutdown through the test device and Bochs might fail.
> Just hang in a loop that executes halt in such cases.
> 
> Signed-off-by: Nadav Amit <nadav.amit@gmail.com>
> ---
>  lib/x86/io.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/lib/x86/io.c b/lib/x86/io.c
> @@ -99,6 +99,10 @@ void exit(int code)
>  #else
>          asm volatile("out %0, %1" : : "a"(code), "d"((short)0xf4));
>  #endif
> +	/* Fallback */
> +	while (1) {
> +		asm volatile ("hlt" ::: "memory");
> +	}
>  	__builtin_unreachable();

Looks good, we can also drop the __builtin_unreachable() now.