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Date: Thu, 15 May 2025 19:05:15 +0200
From: Ingo Molnar <mingo@kernel.org>
To: Dave Hansen <dave.hansen@intel.com>
Cc: Andrew Zaborowski <andrew.zaborowski@intel.com>, x86@kernel.org,
	linux-sgx@vger.kernel.org, linux-kernel@vger.kernel.org,
	Dave Hansen <dave.hansen@linux.intel.com>,
	Tony Luck <tony.luck@intel.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Borislav Petkov <bp@alien8.de>, Ingo Molnar <mingo@redhat.com>,
	"H . Peter Anvin" <hpa@zytor.com>, balrogg@gmail.com
Subject: Re: [PATCH v2] x86/sgx: Prevent attempts to reclaim poisoned pages
Message-ID: <aCYey1W6i7i3yPLL@gmail.com>
References: <20250508230429.456271-1-andrew.zaborowski@intel.com>
 <448598e9-972f-4807-ba54-fc1f7e141b4f@intel.com>
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* Dave Hansen <dave.hansen@intel.com> wrote:

> Thanks for sending this, Andrew!
> 
> I think I'll probably add a slightly shorter summary:
> 
> tl;dr: SGX page reclaim touches the page to copy its contents to
> secondary storage. SGX instructions do not gracefully handle machine
> checks. Despite this, the existing SGX code will try to reclaim pages
> that it _knows_ are poisoned. Avoid even trying to reclaim poisoned pages.
> 
> But otherwise it looks great:
> 
> Acked-by: Dave Hansen <dave.hansen@linux.intel.com>

Thanks, I've applied this fix to tip:x86/sgx, with the TL;DR paragraph 
added in.

Thanks,

	Ingo