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Fri, 13 Feb 2026 10:27:38 -0800 (PST) From: Askar Safin To: torvalds@linux-foundation.org Cc: christian@brauner.io, cyphar@cyphar.com, hpa@zytor.com, jack@suse.cz, linux-fsdevel@vger.kernel.org, safinaskar@gmail.com, viro@zeniv.linux.org.uk, werner@almesberger.net Subject: Re: [RFC] pivot_root(2) races Date: Fri, 13 Feb 2026 21:27:32 +0300 Message-ID: <20260213182732.196792-1-safinaskar@gmail.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Linus Torvalds : > + /* Special case: 'init' changes everything */ > + if (current == &init_task) { pivot_root is not used by real inits now. pivot_root was actively used by inits in classic initrd epoch, but initrd is not used anymore. pivot_root cannot be used by inits to switch from initramfs (in 6.19) because one cannot unmount or move root of namespace (so everybody moves new root on top of old using "mount --move"). Very recently (in 7.0) pivot_root became viable to switch from initramfs, because of Brauner's nullfs patches. But distros didn't start to use this yet. So, inits now don't use pivot_root. So there is no need to special case it. -- Askar Safin