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Date:   Sun, 22 Aug 2021 15:24:36 +0000
From:   Wei Liu <wei.liu@kernel.org>
To:     David Mozes <david.mozes@silk.us>
Cc:     David Moses <mosesster@gmail.com>, Wei Liu <wei.liu@kernel.org>,
        Michael Kelley <mikelley@microsoft.com>,
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        <tomer432100@gmail.com>,
        "linux-hyperv@vger.kernel.org" <linux-hyperv@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] x86/hyper-v: guard against cpu mask changes in
 hyperv_flush_tlb_others()
Message-ID: <20210822152436.mqfwv3xbqfxy33os@liuwe-devbox-debian-v2>
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On Thu, Aug 19, 2021 at 07:55:06AM +0000, David Mozes wrote:
> Hi Wei ,
> I move the print cpumask to other two places after the treatment on the empty mask see below
> And I got the folwing:
> 
> 
> Aug 19 02:01:51 c-node05 kernel: [25936.562674] Hyper-V: ERROR_HYPERV2: cpu_last=
> Aug 19 02:01:51 c-node05 kernel: [25936.562686] WARNING: CPU: 11 PID: 56432 at arch/x86/include/asm/mshyperv.h:301 hyperv_flush_tlb_others+0x23f/0x7b0
> 
> So we got empty on different place on the code .
> Let me know if you need further information from us.
> How you sagest to handle this situation?
> 

Please find a way to reproduce this issue with upstream kernels.

Thanks,
Wei.