From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.11]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DA6BA35DA5B; Wed, 1 Apr 2026 08:01:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775030483; cv=none; b=RcUYqyYqPB8qutVFNFX9xArB/B0l8DQyxp5aSy9U+jO7zEC2EtPMQQNaISU4Tbtr0dBUeCVuNrrXbKVTrOR0bDLsFyLhpWMCNphMsslgJwDnfiR/wLcm5vp7YAb1neYiiKm4dYVsGeNC9azsgQvNZxttBv6eyK67CY4CSsUd74k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775030483; c=relaxed/simple; bh=4KPcHQaH2A+EIsW/2xhQ1DgUyBDKAUpbyJcONff9D4w=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=gf5i6JwCnfblSZ3QceGcP1tSU0Ks1uoKfGOvE/VRrCOZS1quLF/8s1xprbWJqhxoVGX5TGq8POJMdbJ4EHzRjXIJyzITT5jVcO/0xIfhe1wXZcS3Hh43xRYk/amvya2oWTJegFEkGzS0VI092vhJCM4vLrEa2se+IQ3Q9HY5ISk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=E/BI9vzq; arc=none smtp.client-ip=198.175.65.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="E/BI9vzq" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1775030482; x=1806566482; h=from:to:cc:subject:in-reply-to:references:date: message-id:mime-version; bh=4KPcHQaH2A+EIsW/2xhQ1DgUyBDKAUpbyJcONff9D4w=; b=E/BI9vzqDgg8vqfcsG4PsOIZjZP3ivgAkAR+ecvPCkuAar6vKOGFOa8k rg6PBtnQieWGheoRzps4XPOSDCStjfQLpGtqnZMzLaHHZAeCESB4HuuLx nwGeAfxx/AJgZFZJDtmeKZ5Z7EMyGRD8Wd00IjAMWfO0ZOScXpNAKRcN2 ckF4HVT0LF7bmTjY26wRznFISimsHALoaCfumNWCJTkd55ys2sF3k++ae RKNgyl1HuOZb6lcjPW68VAWprlgMm1zgKMFTubzzbcT/jb/Uu8Ai+mWcr LonPT/fC1PdpUX8Rb5dFPL7YLFc8RMuVthlcpq25wsBYwp1DBr1p0VweJ Q==; X-CSE-ConnectionGUID: jCRtpvLKQemjmmW6phx7Yg== X-CSE-MsgGUID: HbByzR/aT1ODto1Sx5QS1g== X-IronPort-AV: E=McAfee;i="6800,10657,11745"; a="86363841" X-IronPort-AV: E=Sophos;i="6.23,153,1770624000"; d="scan'208";a="86363841" Received: from orviesa001.jf.intel.com ([10.64.159.141]) by orvoesa103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Apr 2026 01:01:21 -0700 X-CSE-ConnectionGUID: XfbOVKFJT6iKwii3eVtcsQ== X-CSE-MsgGUID: 9OKPY4FESdub/5FB3tfE4A== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,153,1770624000"; d="scan'208";a="264536738" Received: from tassilo.jf.intel.com (HELO tassilo.localdomain) ([10.54.38.190]) by orviesa001.jf.intel.com with ESMTP; 01 Apr 2026 01:01:21 -0700 Received: by tassilo.localdomain (Postfix, from userid 1000) id D5F61302965; Wed, 01 Apr 2026 01:01:20 -0700 (PDT) From: Andi Kleen To: Calvin Owens Cc: linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, x86@kernel.org, Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Alexander Shishkin , Jiri Olsa , Ian Rogers , Adrian Hunter , James Clark , Thomas Gleixner , Borislav Petkov , Dave Hansen , "H. Peter Anvin" Subject: Re: [PATCH 0/2] Two semi-related perf throttling fixes In-Reply-To: (Calvin Owens's message of "Tue, 31 Mar 2026 08:25:48 -0700") References: Date: Wed, 01 Apr 2026 01:01:20 -0700 Message-ID: <87y0j7w1m7.fsf@linux.intel.com> User-Agent: Gnus/5.13 (Gnus v5.13) Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain Calvin Owens writes: > Hi all, > > In the course of investigating [1], I set out to understand why this > sequence of messages is printed every boot, even when nobody is using > perf at all: I don't think i've ever seen that just from the NMI watchdog. I wonder what is different on your machines. And of course the PMU based NMI watchdog is on the way out. But the fixes make sense to me. Reviewed-by: Andi Kleen