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Sender: Ingo Molnar <mingo.kernel.org@gmail.com>
Date: Thu, 11 Apr 2024 10:43:12 +0200
From: Ingo Molnar <mingo@kernel.org>
To: Nikita Kiryushin <kiryushin@ancud.ru>
Cc: 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>,
	Peter Zijlstra <peterz@infradead.org>,
	Ashok Raj <ashok.raj@intel.com>,
	David Woodhouse <dwmw@amazon.co.uk>, linux-kernel@vger.kernel.org,
	lvc-project@linuxtesting.org
Subject: Re: [PATCH] x86/smpboot: Add map vars allocation check in
 smp_prepare_cpus_common
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* Nikita Kiryushin <kiryushin@ancud.ru> wrote:

> But I have some questions considering __GFP_NOFAIL. It clearly shows, 
> that allocation will not fail/is not expected to fail, does it not try 
> making allocation until it succeeds? Would not it make the system hang in 
> a problematic case?

Yes, which is better than undefined behavior. This case should only happen 
on hopelessly buggy kernels or hopelessly buggy hardware - which will very 
likely crash way sooner before they get into this part of the init 
sequence.

This whole problem is a non-issue.

Thanks,

	Ingo