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Date:   Thu, 4 May 2023 15:41:13 -0700
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Subject: Re: [RFC PATCH V5 15/15] x86/sev: Fix interrupt exit code paths from
 #HV exception
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To:     Tom Lendacky <thomas.lendacky@amd.com>, luto@kernel.org,
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 <20230501085726.544209-16-ltykernel@gmail.com>
 <3c91e1ab-29f4-09cb-1268-52fd9c3e34f4@amd.com>
From:   Tianyu Lan <ltykernel@gmail.com>
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On 5/1/2023 9:02 AM, Tom Lendacky wrote:
>> From: Ashish Kalra <ashish.kalra@amd.com>
>>
>> Add checks in interrupt exit code paths in case of returns
>> to user mode to check if currently executing the #HV handler
>> then don't follow the irqentry_exit_to_user_mode path as
>> that can potentially cause the #HV handler to be
>> preempted and rescheduled on another CPU. Rescheduled #HV
>> handler on another cpu will cause interrupts to be handled
>> on a different cpu than the injected one, causing
>> invalid EOIs and missed/lost guest interrupts and
>> corresponding hangs and/or per-cpu IRQs handled on
>> non-intended cpu.
>>
>> Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
> 
> This should be merged into one of the appropriate #HV patches and just 
> add Ashish with a Co-developed-by: tag where appropriate. This would be 
> appropriate as a separate only if discovered after the series was merged.

Sure. Will update in the next version.