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Date: Sat, 12 Mar 2016 16:31:07 +0100
From: Ingo Molnar <mingo@kernel.org>
To: Andy Lutomirski <luto@kernel.org>
Cc: X86 ML <x86@kernel.org>, Paolo Bonzini <pbonzini@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>, KVM list <kvm@vger.kernel.org>,
        Arjan van de Ven <arjan@linux.intel.com>,
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        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH v3 2/5] x86/msr: Carry on after a non-"safe" MSR access
 fails without !panic_on_oops
Message-ID: <20160312153107.GA17873@gmail.com>
References: <cover.1457723023.git.luto@kernel.org>
 <35f2f107e0d85473a0e66c08f93d571a9c72b7fc.1457723023.git.luto@kernel.org>
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* Andy Lutomirski <luto@kernel.org> wrote:

> +bool ex_handler_rdmsr_unsafe(const struct exception_table_entry *fixup,
> +			     struct pt_regs *regs, int trapnr)
> +{
> +	WARN(1, "unsafe MSR access error: RDMSR from 0x%x",
> +	     (unsigned int)regs->cx);

Please make this WARN_ONCE(). There's no point in locking up the system with 
WARN() spam, should this trigger frequently.

> +	WARN(1, "unsafe MSR access error: WRMSR to 0x%x (tried to write 0x%08x%08x)\n",
> +	     (unsigned int)regs->cx,
> +	     (unsigned int)regs->dx, (unsigned int)regs->ax);

Ditto.

Thanks,

	Ingo