From: Andrew Cooper <andrew.cooper3@citrix.com>
To: seanjc@google.com
Cc: Andrew Cooper <andrew.cooper3@citrix.com>,
chao.gao@intel.com, kvm@vger.kernel.org,
linux-kernel@vger.kernel.org, pbonzini@redhat.com
Subject: Re: [PATCH] KVM: x86: Do not change ICR on write to APIC_SELF_IPI
Date: Fri, 23 Oct 2026 21:50:20 +0100 [thread overview]
Message-ID: <9e3c40e9-d211-432b-ac1e-19cd878257e6@citrix.com> (raw)
In-Reply-To: <YhekNhrK7VKW1jDV@google.com>
> On Thu, Feb 24, 2022, Paolo Bonzini wrote:
>> Emulating writes to SELF_IPI with a write to ICR has an unwanted side
>> effect: the value of ICR in vAPIC page gets changed. The lists
>> SELF_IPI as write-only, ^
>> |- SDM
>>
>> with no associated MMIO offset, so any write should have no visible
>> side effect in the vAPIC page. Reported-by: Chao Gao
>> <chao.gao@intel.com> Signed-off-by: Paolo Bonzini
>> <pbonzini@redhat.com> ---
>
> Reviewed-by: Sean Christopherson <seanjc@google.com>
This patch was just attempted to be ported to Xen.
Contrary to the claim, Intel Core (P-cores) really do overwrite ICR when
processing SELF_IPI.
~Andrew
prev parent reply other threads:[~2026-10-23 20:50 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-24 14:54 Paolo Bonzini
2022-02-24 15:28 ` Sean Christopherson
2026-10-23 20:50 ` Andrew Cooper [this message]
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