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Date: Fri, 19 Jan 2024 22:30:22 +0530
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Subject: Re: [PATCH] mm, kmsan: fix infinite recursion due to RCU critical
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To: Marco Elver <elver@google.com>
CC: Andrew Morton <akpm@linux-foundation.org>,
        Alexander Potapenko
	<glider@google.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        Thomas Gleixner
	<tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
        Borislav Petkov
	<bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>, <x86@kernel.org>,
        "H. Peter Anvin" <hpa@zytor.com>, <kasan-dev@googlegroups.com>,
        <linux-kernel@vger.kernel.org>, <linux-mm@kvack.org>,
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References: <20240118110022.2538350-1-elver@google.com>
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From: Charan Teja Kalla <quic_charante@quicinc.com>
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On 1/18/2024 5:52 PM, Marco Elver wrote:
> It would be nice to avoid duplicating functions - both options have downsides:
> 1. Shared pfn_valid(): it might break for KMSAN again in future if new
> recursion is introduced.
> 2. KMSAN-version of pfn_valid(): it might break if pfn_valid() changes
> in future.
> 
> I suspect #1 is less likely.
> 
> What is your main concern by switching to rcu_read_lock_sched()?

No concerns from my side. Just wanted to know the thought behind
changing the pfn_valid instead of kmsan version, like for some
functions. Thanks for the clarification.