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Subject: Re: [v7, 05/11] x86/retpoline/entry: Convert entry assembler indirect
 jumps
To: Andi Kleen <ak@linux.intel.com>,
        Andrei Vagin <avagin@virtuozzo.com>
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From: Dave Hansen <dave.hansen@intel.com>
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Date: Tue, 9 Jan 2018 20:39:21 -0800
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On 01/09/2018 08:30 PM, Andi Kleen wrote:
> On Tue, Jan 09, 2018 at 07:54:08PM -0800, Andrei Vagin wrote:
>>
>> In my test environment, the kernel with this patch crashes.
> 
> I posted a patch for this.

It's called:

[PATCH v3 2/3] x86/retpoline: Use better sequences for NOSPEC_CALL/JMP

right, Andi?

BTW, that's a fun oops.  It looks like it's call'ing (or jumping) to an
address that's used by cpu_entry_area->exception_stacks[1].