From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f202.google.com (mail-pl1-f202.google.com [209.85.214.202]) (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 43015221DBD for ; Fri, 8 Aug 2025 22:59:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754693972; cv=none; b=P4/tv6XMgQw+HUSzrznF3VHzNBJR8zHR7nSFGk7OoyjwVmnU4dWiCAYZIFrNxi/GmhMaJfMAsBwT7/Ib8lqF22RcViyVlYjdKTWMH+U+KuWDa8mwWhSc3GRnB5u1IM9as8wJBA2A70l4+2kflYZF+DZcgWv4WnV1ZRi0I14FM+s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754693972; c=relaxed/simple; bh=fNFpdQ+jg6cStsERoB7GG94pOCw3WR3BzUnZR/FRaQk=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=KP7wkLl3vC4Zf7Vc0CZ430ERbD1YdI0qlf5/6706vQ+nyaQsT1g4RgPOyvjAmPo40x0TS5UGqepm7GK3VArw4eLbp9URZIufps80HdNk2yuzuQ2Z6SzQAicMCgDqENRmI8EilWVBTg578idWBezXTmdigWz6qSgJJWtIHEPKRiA= 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=0bMROWCY; arc=none smtp.client-ip=209.85.214.202 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="0bMROWCY" Received: by mail-pl1-f202.google.com with SMTP id d9443c01a7336-240607653f4so22625465ad.3 for ; Fri, 08 Aug 2025 15:59:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1754693970; x=1755298770; 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=DiLmZgWhRF1Ot9ulosGMfLSlI9WhewVMmUcNccmagMw=; b=0bMROWCYbKW4b+jfFxQO30FGcMm7NogKxfe7ukUYVDDZopnURkI0C73LgSWSq9kg3H WkTupgwpQ1mvbwNw1IpX6e9EPnxuBaSUne/qRGng29jBf70zklhRLF38lARM5W3pQ4j9 ogyi35SroULqrzzeld6FHbIx7F9WwBCW716nLL5EfkDgoiEPHaUcNnv7AXFL6ilUZa3H Oc7RVET5MPY+daGGU7XI05N/nBHdIveJiFDwVmXj+iUKXm4FgAkPq9/c8NUs0dhosKdx U7rqHXL6Tw9nHm0KqMF16DMuO2/m6NehlrDKlSmWQLnqrNMV0GXgU0aH5GvYPw/D8s1i GUzw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1754693970; x=1755298770; 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=DiLmZgWhRF1Ot9ulosGMfLSlI9WhewVMmUcNccmagMw=; b=V/y9r/BzdCX/HTLPEgbAJUFzM2+v1FN5u6jGjOLeYIoaTyAXxmt+WVcrIPhGTzRvMX IRjPzOGQV3hz67XYpxTZEM6adp7JkuZxDKXAQWqp3G6AV02aYjDlBUFKWQo3WyyaRQ8Z NWiPb2NeXlaOFHzd/SYkfN5Npfr6B4Zj9qYiT+ADr1wx582FVFT1DH63wiLyxQuDKwzh U4tec2kqf9uqzwToun0rBs4W9TworZaXzz0SD7J8ROHKHjy40i6N6O3bxHEsoU0doFsS NV6vx97ho7znahZnoDkR1r1SbyDNzP8YUsFSsBYV840UjPK7N1C/u+umTspFkdssEpFU v+zA== X-Gm-Message-State: AOJu0Yys40BlD4GWLBPfPox/ShDa0VM/qpaahNOk966n8YBp6j1gNJ/S PnW0mPClpgSc0b/GTXo4rGAW9TSSEd13ZK/EaHOewoOs/G3yCISpWhcfiEqdLltj0YMyCcPprkC tQoLP+A== X-Google-Smtp-Source: AGHT+IFyppIVS+5+frYoRbNM7fhmMKbIK7z1xCvI1f1zBWOIlSbk4GaQIf+8f7BA8u60irOnBKaXSLB8OYs= X-Received: from plbld13.prod.google.com ([2002:a17:902:facd:b0:240:3c28:33c0]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:903:1a28:b0:234:98eb:8eda with SMTP id d9443c01a7336-242c21dda5fmr57355365ad.28.1754693970550; Fri, 08 Aug 2025 15:59:30 -0700 (PDT) Date: Fri, 8 Aug 2025 15:59:28 -0700 In-Reply-To: Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: Message-ID: Subject: Re: [Bug 218792] Guest call trace with mwait enabled From: Sean Christopherson To: bugzilla-daemon@kernel.org Cc: kvm@vger.kernel.org Content-Type: text/plain; charset="us-ascii" On Fri, Aug 08, 2025, bugzilla-daemon@kernel.org wrote: > https://bugzilla.kernel.org/show_bug.cgi?id=218792 > > Len Brown (lenb@kernel.org) changed: > > What |Removed |Added > ---------------------------------------------------------------------------- > CC| |lenb@kernel.org > > --- Comment #6 from Len Brown (lenb@kernel.org) --- > Re: intel_idle > > I agree that the SDM doesn't guarantee this MSR exists > based on the presence of PC10. > > I'm not opposed to _safe(). > > but... > > Why is this "platform" advertising PC10 (or any MWAIT C-states) to intel_idle > in the first place? Because letting the guest execute MONITOR/MWAIT natively, and thus get into deeper sleep states, is advantageous for all the same reasons bare metal CPUs want to get into deep sleep states, e.g. to let active cores hit higher turbo bins.