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Date: Tue, 25 Jun 2024 09:52:04 +0200
From: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
To: Shiji Yang <yangshiji66@outlook.com>
Cc: linux-mips@vger.kernel.org, Arnd Bergmann <arnd@arndb.de>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Javier Martinez Canillas <javierm@redhat.com>,
	Khalid Aziz <khalid@gonehiking.org>, Baoquan He <bhe@redhat.com>,
	Jiaxun Yang <jiaxun.yang@flygoat.com>,
	Serge Semin <fancer.lancer@gmail.com>, linux-kernel@vger.kernel.org,
	Mieczyslaw Nalewaj <namiltd@yahoo.com>
Subject: Re: [PATCH V2] mips: kernel: fix detect_memory_region() function
Message-ID: <Znp3JKF6UUn2YuvL@alpha.franken.de>
References: <TYCP286MB089598ABD1E2F66003D71EB8BCD52@TYCP286MB0895.JPNP286.PROD.OUTLOOK.COM>
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On Tue, Jun 25, 2024 at 09:44:44AM +0800, Shiji Yang wrote:
> The detect_memory_region() has been broken on 6.6 kernel[1]. This
> patch fixes it by:
> 1. Do not use memcmp() on unallocated memory, as the new introduced
>    fortify dynamic object size check[2] will return unexpected result.

hmm, so there should a new way for doing memory probing without
triggering this fortify check. How do other platforms deal with this ?

> 2. Use a fixed pattern instead of a random function pointer as the
>    magic value.

why is this better ?

Thomas.

-- 
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
good idea.                                                [ RFC1925, 2.3 ]