From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.17]) (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 54DA117BED0; Thu, 14 Nov 2024 17:13:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.17 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731604434; cv=none; b=X48To96Yy6lDOGX7jyAcLZ1XSYbCkO9chPA4xIUiZJtggPeDDaUAulihNh0uHSvZbh2J+8gNDgzdlWlUdbsVxuIBFmUFkrnQHbq6ZYIQZWGB2NmrhdM/wbaR7ChNqtwATf6Y0q+uVW3cYOiWdRf99uuHymSiIH3RRWBHi7hjVtk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731604434; c=relaxed/simple; bh=/LZlSOccn1m3pAZvKwPhMaD9G7pEsN/iu8vODiTHqP4=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Otu4u/31M0Sdv5peXQiIqlhb3YcAgRsnrhjwI08Hu7VQs7dy7qODAQk0mBNokPIYouPyqeNRzrYHIz4WPK8oFG4gw5R+srBUen/l3Jq/Cxf4g46qIWkG5atXI0hbxtUD179mJNvSEbD9jbqwa7P/yhY5T7zLRgq2zpGloC6tqT0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=none smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=FZ3SCvGM; arc=none smtp.client-ip=192.198.163.17 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none 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="FZ3SCvGM" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1731604433; x=1763140433; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=/LZlSOccn1m3pAZvKwPhMaD9G7pEsN/iu8vODiTHqP4=; b=FZ3SCvGMd36qfsNCvrnaxNVtPGDN4xg4chzfZifyzC4jdU5hD3R18HVn 6g/a6/veeVeBmt2B8pHJxCvnVTeKJFbGb8jkceIrX97+41b5qboAo8zrh ArNoYeg/CkCydSZ3G5rI60GdacGL5Z4KU9CPLWMYzIL/AEdHGi7XvNGSE 5l/KEZVLeqkxOCFbkIJrRRausaccBx5zes2fL0R656AUxFR6wkwO7dbMX SjddpYV9Obxnz37k9daTL8id+zoiknr5sTQWAByOKWwiP3mC8obCMwQBU D/ycK1HGGs4Cegn8S+NJ5Zqx2g2epczIK4YsMmeNR4qm3HQGRbeZ5peF+ w==; X-CSE-ConnectionGUID: yFRr4VvbTvqYPd4lbMOHxg== X-CSE-MsgGUID: 2NKYg+JzR7yCjm/ssEBWnQ== X-IronPort-AV: E=McAfee;i="6700,10204,11256"; a="31471533" X-IronPort-AV: E=Sophos;i="6.12,154,1728975600"; d="scan'208";a="31471533" Received: from fmviesa002.fm.intel.com ([10.60.135.142]) by fmvoesa111.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Nov 2024 09:13:53 -0800 X-CSE-ConnectionGUID: 0uX9F+DhS52CIvl7k1yOwg== X-CSE-MsgGUID: EunNGp7GSvOC1rF2/IZ2og== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.12,154,1728975600"; d="scan'208";a="111581703" Received: from johunt-mobl9.ger.corp.intel.com (HELO [10.245.244.40]) ([10.245.244.40]) by fmviesa002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Nov 2024 09:13:49 -0800 Message-ID: <15d18759-68eb-4683-9255-715545505ed6@linux.intel.com> Date: Thu, 14 Nov 2024 18:13:39 +0100 Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 0/3] SRF: Fix offline CPU preventing pc6 entry To: Thomas Gleixner Cc: x86@kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, rafael.j.wysocki@intel.com, len.brown@intel.com, artem.bityutskiy@linux.intel.com, dave.hansen@linux.intel.com, Peter Zijlstra References: <20241108122909.763663-1-patryk.wlazlyn@linux.intel.com> <20241112114543.GP22801@noisy.programming.kicks-ass.net> <1ee47890-7f19-4c21-9d0d-94834d716159@linux.intel.com> <87o72klylj.ffs@tglx> Content-Language: en-US From: Patryk Wlazlyn In-Reply-To: <87o72klylj.ffs@tglx> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit > That's not really working: > >   1) Regular kexec offlines them again. But then, they execute hlt loop in the reboot vector right? I think that's fine. We just don't want to be woken up from the mwait when the RIP points to garbage. >   2) Kexec in panic can't do any of that. Does it make sense to change the kexec, so that every CPU is forced into the reboot vector, which I believe happens for online CPUs? We don't have to online them all the way. Maybe minimal bringup just to be able to send them the IPI? As a side note, It's not that important for this patchset. I think I can make it work without simplifying the existing hack, but crossed my mind at some point that maybe we could do that.