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Date: Thu, 7 Mar 2024 20:27:45 +0000
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Message-ID: <ZeojMwHh8O73bw23@google.com>
Subject: Re: [RFC PATCH 3/3] x86/mm: cleanup prctl_enable_tagged_addr()
 nr_bits error checking
From: Yosry Ahmed <yosryahmed@google.com>
To: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>, Thomas Gleixner <tglx@linutronix.de>, 
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>, Dave Hansen <dave.hansen@intel.com>, 
	Peter Zijlstra <peterz@infradead.org>, Andy Lutomirski <luto@kernel.org>, x86@kernel.org, 
	linux-mm@kvack.org, linux-kernel@vger.kernel.org
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On Thu, Mar 07, 2024 at 07:31:44PM +0200, Kirill A. Shutemov wrote:
> On Thu, Mar 07, 2024 at 01:39:16PM +0000, Yosry Ahmed wrote:
> > In prctl_enable_tagged_addr(), we check that nr_bits is in the correct
> > range, but we do so in a twisted if/else block where the correct case is
> > sandwiched between two error cases doing exactly the same thing.
> > 
> > Simplify the if condition and pull the correct case outside with the
> > rest of the success code path.
> 
> I'm okay either way.
> 
> I structured the code this way as I had separate patch that adds also
> LAM_U48. But it is unlikely to get upstreamed.

I see, thanks for the context. For now, I think this makes the code a
little bit clearer.