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X-CSE-ConnectionGUID: rc4ZZ+v/RSiHGOeiYYVvKg== X-CSE-MsgGUID: 0RlNXHOMTUG09w1XQk95Cw== X-IronPort-AV: E=McAfee;i="6800,10657,11569"; a="71850981" X-IronPort-AV: E=Sophos;i="6.18,306,1751266800"; d="scan'208";a="71850981" Received: from orviesa009.jf.intel.com ([10.64.159.149]) by orvoesa103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Oct 2025 07:32:22 -0700 X-CSE-ConnectionGUID: n/jcZQ2OQ4aISUVSM9b5Xw== X-CSE-MsgGUID: GNgymIzPSY6d14nXtfkz5Q== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.18,306,1751266800"; d="scan'208";a="178414003" Received: from cmdeoliv-mobl4.amr.corp.intel.com (HELO [10.125.109.184]) ([10.125.109.184]) by orviesa009-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Oct 2025 07:32:21 -0700 Message-ID: Date: Wed, 1 Oct 2025 07:32:21 -0700 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 4/7] x86/kexec: Disable kexec/kdump on platforms with TDX partial write erratum To: Vishal Annapurve Cc: Paolo Bonzini , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, bp@alien8.de, tglx@linutronix.de, peterz@infradead.org, mingo@redhat.com, hpa@zytor.com, thomas.lendacky@amd.com, x86@kernel.org, kas@kernel.org, rick.p.edgecombe@intel.com, dwmw@amazon.co.uk, kai.huang@intel.com, seanjc@google.com, reinette.chatre@intel.com, isaku.yamahata@intel.com, dan.j.williams@intel.com, ashish.kalra@amd.com, nik.borisov@suse.com, chao.gao@intel.com, sagis@google.com, farrah.chen@intel.com, Binbin Wu References: <20250901160930.1785244-1-pbonzini@redhat.com> <20250901160930.1785244-5-pbonzini@redhat.com> <74a390a1-42a7-4e6b-a76a-f88f49323c93@intel.com> From: Dave Hansen Content-Language: en-US Autocrypt: addr=dave.hansen@intel.com; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 9/30/25 19:05, Vishal Annapurve wrote: ... >> Any workarounds are going to be slow and probably imperfect. That's not > > Do we really need to deploy workarounds that are complex and slow to > get kdump working for the majority of the scenarios? Is there any > analysis done for the risk with imperfect and simpler workarounds vs > benefits of kdump functionality? > >> a great match for kdump. I'm perfectly happy waiting for fixed hardware >> from what I've seen. > > IIUC SPR/EMR - two CPU generations out there are impacted by this > erratum and just disabling kdump functionality IMO is not the best > solution here. That's an eminently reasonable position. But we're speaking in broad generalities and I'm unsure what you don't like about the status quo or how you'd like to see things change. Care to send along a patch representing the "best solution"? That should clear things up.