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Message-ID: <1511b773-5f79-4882-9566-e0db8d8f53b3@intel.com>
Date: Thu, 29 Feb 2024 11:21:36 +1300
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH 1/4] x86/coco: Add a new CC attribute to unify cache flush
 during kexec
Content-Language: en-US
To: Borislav Petkov <bp@alien8.de>
CC: "dyoung@redhat.com" <dyoung@redhat.com>, "Gao, Chao" <chao.gao@intel.com>,
	"luto@kernel.org" <luto@kernel.org>, "Hansen, Dave" <dave.hansen@intel.com>,
	"x86@kernel.org" <x86@kernel.org>, "bhe@redhat.com" <bhe@redhat.com>,
	"peterz@infradead.org" <peterz@infradead.org>, "hpa@zytor.com"
	<hpa@zytor.com>, "mingo@redhat.com" <mingo@redhat.com>,
	"thomas.lendacky@amd.com" <thomas.lendacky@amd.com>,
	"kirill.shutemov@linux.intel.com" <kirill.shutemov@linux.intel.com>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"tglx@linutronix.de" <tglx@linutronix.de>, "nik.borisov@suse.com"
	<nik.borisov@suse.com>, "pbonzini@redhat.com" <pbonzini@redhat.com>
References: <20240219203222.GIZdO61ucfq4bFxRT0@fat_crate.local>
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 <CALu+AoR-VFHCK_7LHiJ3z_Vk1B=sFS90iAyCs9qmSmf2+XORLw@mail.gmail.com>
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 <8c3e3e8c32b50cf488413d965ac6730ce8814214.camel@intel.com>
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From: "Huang, Kai" <kai.huang@intel.com>
In-Reply-To: <20240228110207.GCZd8Sr8mXHA2KTiLz@fat_crate.local>
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On 29/02/2024 12:02 am, Borislav Petkov wrote:
> On Wed, Feb 28, 2024 at 09:21:00AM +0000, Huang, Kai wrote:
>> Based on this I'll change to do unconditional WBINVD during kexec() for in
>> stop_this_cpu() and relocate_kernel().  Please let me know if you have any
>> comments.
> 
> Yes, pls make sure to summarize in the commit message what this thread
> figured out. But basically, we want to try the simple approach and
> WBINVD unconditionally on the CPU stopping path so that caches are clean
> and there's no potential issues...
> 

Yes will do.  Thanks for the feedback.