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AJvYcCVNXGxvQ4c29IcFYh4Tai8ZdTRjV7i8CyFaVVBXZ4Vri5EE950cSLaYxPf6sDbr4nFAqL7xQBkqFpxIDvE=@vger.kernel.org X-Gm-Message-State: AOJu0YxS4wj7xz54tIsdXnw9tAeWvgt5P5x+PNns4C/GF8j/mewN+P4B KOQcZWhF/IpA4ccC+rdLF+0Hla2SPsgTas6vHJVeOgzKEgvWp5klWSJ3LcZu1wfYdh/vect+M34 ++A== X-Google-Smtp-Source: AGHT+IGDSdE1ytyBoBFw7qVwuVm3wbv2xNCX9zlmSDFB9e6T2jpMlLpSaA4AhKeFzgmz0ROgTRp2/3598EM= X-Received: from pjbpd14.prod.google.com ([2002:a17:90b:1dce:b0:2fa:e9b:33b7]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:3844:b0:2ff:53d6:2b82 with SMTP id 98e67ed59e1d1-301d43a2db5mr6626003a91.11.1742493271988; Thu, 20 Mar 2025 10:54:31 -0700 (PDT) Date: Thu, 20 Mar 2025 10:54:30 -0700 In-Reply-To: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250320142022.766201-1-seanjc@google.com> <20250320142022.766201-4-seanjc@google.com> Message-ID: Subject: Re: [PATCH v2 3/3] KVM: x86: Add a module param to control and enumerate device posted IRQs From: Sean Christopherson To: Jim Mattson Cc: Paolo Bonzini , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Yosry Ahmed Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable On Thu, Mar 20, 2025, Jim Mattson wrote: > On Thu, Mar 20, 2025 at 7:31=E2=80=AFAM Sean Christopherson wrote: > > > > Add a module param to allow disabling device posted interrupts without > > having to sacrifice all of APICv/AVIC, and to also effectively enumerat= e > > to userspace whether or not KVM may be utilizing device posted IRQs. > > Disabling device posted interrupts is very desirable for testing, and c= an > > even be desirable for production environments, e.g. if the host kernel > > wants to interpose on device interrupts. >=20 > Are you referring to CONFIG_X86_POSTED_MSI, or something else that > doesn't exist yet? Yeah, that, and/or out-of-tree hackery to do similar coalescing (or ratelim= iting).