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Date: Wed, 7 May 2025 06:47:54 +0200
From: Christoph Hellwig <hch@lst.de>
To: Kees Cook <kees@kernel.org>
Cc: Keith Busch <kbusch@kernel.org>, kernel test robot <lkp@intel.com>,
	Jens Axboe <axboe@kernel.dk>, Christoph Hellwig <hch@lst.de>,
	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: <20250507044754.GC28402@lst.de>
References: <20250507033536.work.088-kees@kernel.org>
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On Tue, May 06, 2025 at 08:35:40PM -0700, Kees Cook wrote:
> The only reason nvme_pci_npages_prp() could be used as a compile-time
> known result in BUILD_BUG_ON() is because the compiler was always choosing
> to inline the function. Under special circumstances (sanitizer coverage
> functions disabled for __init functions on ARCH=um), the compiler decided
> to stop inlining it:

Can we place just fix um to still force inlining inline functions instead
of needing these workarounds?