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 869B31401B for ; Tue, 5 Aug 2025 00:54:05 +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=1754355246; cv=none; b=A0fKOmvxMZwavMVr1wb14RHP2/uZDNjU1F960oaFLFxGu8caNNl6a2I2YsrkyvEjrJLuLal2g53Ip//xLquDTdxSHi6KSOcCAC1RRQ4VaDRqGM2Zdgp0v8Csc2vPVOa2e0Fqcfk6rj1juu1zdzAhjBt1oEw/d2YQsg/hq/IUWtc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754355246; c=relaxed/simple; bh=FFdH34Y9HowedidO8AMmBlMiHCYieYF/CPEAxL3qGKA=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=LKNPj5V4JZiHI9Q/VotkKCOxg0ZM3PN+75OvWFnUyZT4H4wP+/5aZycwfcA6emVKSfe25jYbhnqUa1cVemtHUSemWTWmvA41IJAgQxloAwzTe6hTC60vhJpjKZt6qgfukpIoW851w4cqie0/u48Q3cuLP0fPrrp+xwluFdGwjQA= 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=U1C8covj; 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="U1C8covj" Received: by mail-pj1-f73.google.com with SMTP id 98e67ed59e1d1-31ecb3a3d0aso4611499a91.3 for ; Mon, 04 Aug 2025 17:54:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1754355245; x=1754960045; 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=HnYyO3awZ0p4a3WeYpLVM8RxiQLoBTvUlR+pcd54P0Y=; b=U1C8covjIxIcnnvapU/kR3HrlUM1tfgzTh6FjWT897GWCoMsKm7B3S8yZDuUjh+hza sbSGFbemaWE0djWBBHa7hFR/ARMW3XAOuBqrYBadvDhiXiNhXC1MAkTFvExha6tYLCRT 98VgdBsebM0Gt3XcNMpuncPPUrhdwu6N3qI0TQH2lSkNckhKJm30YBkQxhq7VhxPj39i e2yUxB1ekwFRzfVrB2UVbMlJpBzv5wHh7y8WRUx4btrjwbefTLqYTjjXVrl/2rH2N7Xr NxNa9T9KRGi4xa2SGkJ09bwtQVwLd9urd5fmZiJ9C9lZhkqodsTn+RAhJI9+oTKB1XJ/ KWOg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1754355245; x=1754960045; 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=HnYyO3awZ0p4a3WeYpLVM8RxiQLoBTvUlR+pcd54P0Y=; b=v2OQDDjQNt/l10bThNp+EE1Cu+mx6mL6CuOK1B4FGZDTNc2WIWR6wm7PweuLyTr59m KLNnTQEUogmccrMeklr7kU2g9Nr+bQI7sXCUZPMGYxyH1UGtBm6oW9j1Gw4JY7t/b2Mq TPNRriABfYdgdztVF6I4FvJTF6fLTIM4IqmGNAp4LXFxrB2pjSfaIfjj2P0eojbXIRPX 99lS0EA/4jqPL5yw+kxxr7OswnzO9itGj0hrWtFHHLV7fdScgyz01Wu0XiXi0pbgBQIt mtUyCff/u0mZu1JjcBWsd6W8YNHST3uuXMrxcXbkTjGD4NnlQNWh+VHNNfh1okHcN919 DmqQ== X-Forwarded-Encrypted: i=1; AJvYcCXi3iXq4I7sqsvjAWcFH0HfB3uzGJ6wOKo4v7MT3TS1vYCH066KF3pSvpN9h8gs0p2kj3MUZV5oS+gP1HQ=@vger.kernel.org X-Gm-Message-State: AOJu0YwVAiAx9KlFvvMNRA3upySHMwn+HuX+tKo8cNCRyg+KQtB/ds2Q JG35TEL2cugrNWoEgcTlS99Jn+zJyDjsxW0gUC3JxTQZSYseXG2p7yd5SBV/6ItMWpW374b/dYp ns910Fw== X-Google-Smtp-Source: AGHT+IHgN8sz9idD1zUFlU9yymn8l6XJp4oewuncjBPKVnSTsjJkkM6MeA40sbodBjsLi1AvBiuvLXTAy5w= X-Received: from pjbsx15.prod.google.com ([2002:a17:90b:2ccf:b0:31f:37f:d381]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:4c88:b0:31c:3651:2d18 with SMTP id 98e67ed59e1d1-321162b20bemr16301922a91.16.1754355244905; Mon, 04 Aug 2025 17:54:04 -0700 (PDT) Date: Mon, 4 Aug 2025 17:54:03 -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: <20250324173121.1275209-1-mizhang@google.com> <20250324173121.1275209-21-mizhang@google.com> <7dc97db7-5eea-4b65-aed3-4fc2846e13a6@linux.intel.com> <7de2b6ed-af39-4434-9ead-5b06ed4761c5@linux.intel.com> Message-ID: Subject: Re: [PATCH v4 20/38] KVM: x86/pmu: Check if mediated vPMU can intercept rdpmc From: Sean Christopherson To: Dapeng Mi Cc: Sandipan Das , Mingwei Zhang , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Paolo Bonzini , Mark Rutland , Alexander Shishkin , Jiri Olsa , Ian Rogers , Adrian Hunter , Liang@google.com, Kan , "H. Peter Anvin" , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-kselftest@vger.kernel.org, Yongwei Ma , Xiong Zhang , Jim Mattson , Zide Chen , Eranian Stephane , Shukla Manali , Nikunj Dadhania Content-Type: text/plain; charset="us-ascii" On Fri, Aug 01, 2025, Sean Christopherson wrote: > On Wed, Jul 30, 2025, Dapeng Mi wrote: > > > > On 7/30/2025 8:38 AM, Sean Christopherson wrote: > > > On Tue, Jul 29, 2025, Dapeng Mi wrote: > > >> BTW, Sean, may I know your plan about the mediated vPMU v5 patch set? Thanks. > > > I'll get it out this week (hopefully tomorrow). > > > > Thumbs up! Thanks. > > I lied, I'm not going to get it out until Monday. Figuring out how to deal with > instruction emulation in the fastpath VM-Exit handlers took me longer than I was > hoping/expecting. > > It's fully tested, and I have all but one changelog written, but I'm out of time > for today (I made a stupid goof (inverted a !) that cost me an ~hour today, *sigh*). > > Unless I get hit by a meteor, I'll get it out Monday. *sigh* Wrong again (fortunately, I didn't get hit by a meteor). Long story short, I revisited (yet again) how to deal with enabling the mediated PMU. I had been doing almost all of my testing with a hack to force-enable a mediated PMU, and when it came time to rip that out, I just couldn't convince myself that requiring userspace to enable KVM_CAP_PMU_CAPABILITY was the best behavior (I especially hated that PMU support would silently disappear). So, bad news is, v5 isn't happening today. Good news is that I think I figured out a not-awful solution for enabling the mediated PMU. I'll post details (and hopefully v5) tomorrow.