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Date: Wed, 7 May 2025 10:00:42 -0600
From: Keith Busch <kbusch@kernel.org>
To: Kees Cook <kees@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>, kernel test robot <lkp@intel.com>,
	Jens Axboe <axboe@kernel.dk>, Sagi Grimberg <sagi@grimberg.me>,
	linux-nvme@lists.infradead.org, Chaitanya Kulkarni <kch@nvidia.com>,
	linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org
Subject: Re: [PATCH] nvme-pci: Make nvme_pci_npages_prp() __always_inline
Message-ID: <aBuDqr-9YCcVfAPi@kbusch-mbp.dhcp.thefacebook.com>
References: <20250507033536.work.088-kees@kernel.org>
 <20250507044754.GC28402@lst.de>
 <202505062255.130383D3B7@keescook>
 <20250507065913.GA31959@lst.de>
 <202505070849.1F48789B6@keescook>
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On Wed, May 07, 2025 at 08:53:06AM -0700, Kees Cook wrote:
> 
> So, the solution for the "accidentally depending on a function to be
> inlined by the compiler" is to mark it as _required_ to be inlined,
> which given its singular use in BUILD_BUG_ON(), looks like the correct
> solution.

That sounds fine to me. Or maybe this should be a #define instead. It
looks like this nvme function evolved from a very different purpose when
it wasn't an integer constant expression, and the comment above it is
outdated.