From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f73.google.com (mail-pj1-f73.google.com [209.85.216.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9E9D53D5248 for ; Thu, 15 Jan 2026 18:06:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768500390; cv=none; b=hZ8aCh3WmWJHNgTYC8zBlgikENSetvWxFr9Za+RLX4SQq6sSgSf0FgIjviH5ZPPR+wXgOw4sP5k9BsvnRR4PjwvOUiQuCZwMdv0SnGVPwRMkn3I81ChMMrCxQd+Zsw2UGKQWqw8iPqAF2U3jCiy8BhT/ufZsGVeB49VJ0zgI/30= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768500390; c=relaxed/simple; bh=bKtZqbraOx9dOngd5gOc23pxRjp5UbEEE52HxF7tfJ4=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=VBR5llMq/6KOfvjrrEvBtcQCoMG9FqItFx64Rm20l6w2ygizOr6vh9AFk0duSzE0Y6G35ExWUho9kqL5NhLSSaOSZaa+CwVBM3iovV+90s+8Z21WDTLKw7cofv2JgClaIxHTLlhh5NQR+753rMgoqTAndxoNkfb0co4GrtOVqn4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=b7qloKh6; arc=none smtp.client-ip=209.85.216.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="b7qloKh6" Received: by mail-pj1-f73.google.com with SMTP id 98e67ed59e1d1-34c3501d784so933355a91.1 for ; Thu, 15 Jan 2026 10:06:29 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1768500389; x=1769105189; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=6Rw/FsQk5S1IECPUe/MKwS3msaeY/HykWtIUhFiY/8I=; b=b7qloKh6BS5TP8jDrdVqJMihBkHFf//zeCaNvlmp8n0B7VtTgwBLUYDp6D5H+cQHIw DAB2uTkzHNVBQHFjVZVvQZn/mHs90COA3bGl+ODUtKR504ifWSstDssp8rhj80HNLXk1 6WtCVLHwvb1SLRb4/PpsRiKy0ZKb/FF96kc5qSEIPlLeGP+Vhs2zK6Wh6giCPKxEe0aX sBMeL8y1BeLrmxgcJ3uSuE69z2LdeZivikynPFcHfSFt6uMD+GGrJgRuNUYOpYxGgTp8 hAVpZe1kpnF3Hy9trZGqWPZoc/VOXJSzNu2Zo4uZ1HxNX9l8jVlT8DJfwczIR48qUrHo lwZQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1768500389; x=1769105189; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=6Rw/FsQk5S1IECPUe/MKwS3msaeY/HykWtIUhFiY/8I=; b=PhZ0/NCBU6GwHViz/b1EsxYZRNABS+rcNypDDvF8Zhofu8RBqpumnNeVVP3delyndH B4wxhsyyhNnd3HvcE2fikLzWoOm4vpcjH6fPhZOxltyYWm+41tdTkM4MiTk4n9KmdjDE Xw9coQw5VaHWuV+tm7wle6HEUM41AEF7hsydTUg7vr16PspE6Zw5gJFBFxPl6oT3MABW C2MEfnAKVc6Pgrgg5QKhFgmbQktxfRxl5zGWfWoP3mNEBXZjlP2F+SN7CQL+Lqqqz9Pj +lyRFa1uNVPrhaaRUr61cpdlXr+CzGcij5fRvNljG4BlGCQ0whKSTEkxyfmf9BpiqT2w pqjA== X-Forwarded-Encrypted: i=1; AJvYcCVem/hZki4C8nzFdDIz+JMZLtFjmIpMxqGQrrEKB+/QTV44nqbFXT3VJB15ndkPwKZnD5Cz2kbmpvByuc4=@vger.kernel.org X-Gm-Message-State: AOJu0YyOvwicIh7SqZYaZyZ/E3KDqZLNOUqyyK8cluYOVy10i8UbEpso ulIoTdSvSRohtUrXzXdRDWNrYweSFzS/kfbEptX9DjPaWb/lJ+SWV/GsIRkb9yGe3YlJdX4HNMV qK1aNpA== X-Received: from pja5.prod.google.com ([2002:a17:90b:5485:b0:34c:4074:d7ec]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90a:c105:b0:343:edb0:1012 with SMTP id 98e67ed59e1d1-35272f6cf04mr202952a91.21.1768500388957; Thu, 15 Jan 2026 10:06:28 -0800 (PST) Date: Thu, 15 Jan 2026 10:03:28 -0800 In-Reply-To: <20260109030657.994759-1-seanjc@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260109030657.994759-1-seanjc@google.com> X-Mailer: git-send-email 2.52.0.457.g6b5491de43-goog Message-ID: <176849900220.720093.4821232985877290250.b4-ty@google.com> Subject: Re: [PATCH] KVM: x86: Ignore -EBUSY when checking nested events from vcpu_block() From: Sean Christopherson To: Sean Christopherson , Paolo Bonzini Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Alessandro Ratti , syzbot+1522459a74d26b0ac33a@syzkaller.appspotmail.com Content-Type: text/plain; charset="utf-8" On Thu, 08 Jan 2026 19:06:57 -0800, Sean Christopherson wrote: > Ignore -EBUSY when checking nested events after exiting a blocking state > while L2 is active, as exiting to userspace will generate a spurious > userspace exit, usually with KVM_EXIT_UNKNOWN, and likely lead to the VM's > demise. Continuing with the wakeup isn't perfect either, as *something* > has gone sideways if a vCPU is awakened in L2 with an injected event (or > worse, a nested run pending), but continuing on gives the VM a decent > chance of surviving without any major side effects. > > [...] Applied to kvm-x86 misc, thanks! [1/1] KVM: x86: Ignore -EBUSY when checking nested events from vcpu_block() https://github.com/kvm-x86/linux/commit/ead63640d4e7 -- https://github.com/kvm-x86/linux/tree/next