From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 851693EC6DC; Sat, 28 Feb 2026 17:42:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772300525; cv=none; b=t8VxExZCkB/k6+TCbuMvLzgtIZVmhXxUYTSSQbpC/spi5e7PMcgXtcqOHlOVO1/uBO15oZ0CdZb/Ldk2TGXnu3CLnqPrp+ajbe0fLZaOf2jBnG0EAATXcdAG7Yp0PgWd6/HNq0hdAPzh4kfZeNarXkcK/gsuWBNoGnxFU6KIgG4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772300525; c=relaxed/simple; bh=exy+B1iLimCn8ZjMhAukkTykOgpYGNDzY5W+gbyRLS0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JZT3Jt9D2HZNDvjLiZ+Z4X5dJYHDeuTFTMaE5DuyDOJR0x4299+QrEY3pxtumjyogE8a39b8BUniIb0H6R2mY3eU10v4ZjBeLyq4draX7vdWR0HUz7uq2VLkNbd/J3WDDHF4xWH0PZ4FJ5Sfgsell9ulxTWXyD7zBViU104uPjk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=EKHvm9b6; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="EKHvm9b6" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9CBF2C2BCAF; Sat, 28 Feb 2026 17:42:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772300525; bh=exy+B1iLimCn8ZjMhAukkTykOgpYGNDzY5W+gbyRLS0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EKHvm9b6fc5siXwjYs/XuGyG1Y166O/e3De6tcbK91/MKWqBrAfx4cysBIW1upcPA ATnvqPByya0pnfS0pWkh8Pn82lbBoIG7yV0XWIhXz0Xevh0BGIuTgvd/rhlALafxT6 PBdXtN++eWoSmx/maN1LjsCMq4KTwk3sPrMh2bMKEYQxzXx/DzjAhOrFfS7oe2m9gg qQ5bmhQwOkvI64rl6O5TpZhuV8wiK12juVb2xwk/Iywnffl6yXz2fOEmLYRc7EupV4 CISqnhcsYCJxffwCN46rY5g70APdjG2aljpKu4CQDmGdTGYH1p+C5nZIr2UWSuqDx2 q4RU5Gr65lPkQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Christian Brauner , Jeff Layton , Sasha Levin Subject: [PATCH 6.19 564/844] fs: ensure that internal tmpfs mount gets mount id zero Date: Sat, 28 Feb 2026 12:27:57 -0500 Message-ID: <20260228173244.1509663-565-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260228173244.1509663-1-sashal@kernel.org> References: <20260228173244.1509663-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit From: Christian Brauner [ Upstream commit a2062463e894039a6fdc2334b96afd91d44b64a8 ] and the rootfs get mount id one as it always has. Before we actually mount the rootfs we create an internal tmpfs mount which has mount id zero but is never exposed anywhere. Continue that "tradition". Link: https://patch.msgid.link/20260112-work-immutable-rootfs-v2-1-88dd1c34a204@kernel.org Fixes: 7f9bfafc5f49 ("fs: use xarray for old mount id") Reviewed-by: Jeff Layton Cc: stable@vger.kernel.org Signed-off-by: Christian Brauner Signed-off-by: Sasha Levin --- fs/namespace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/namespace.c b/fs/namespace.c index f6879f282daec..ecf0e72ce6cfd 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -221,7 +221,7 @@ static int mnt_alloc_id(struct mount *mnt) int res; xa_lock(&mnt_id_xa); - res = __xa_alloc(&mnt_id_xa, &mnt->mnt_id, mnt, XA_LIMIT(1, INT_MAX), GFP_KERNEL); + res = __xa_alloc(&mnt_id_xa, &mnt->mnt_id, mnt, xa_limit_31b, GFP_KERNEL); if (!res) mnt->mnt_id_unique = ++mnt_id_ctr; xa_unlock(&mnt_id_xa); -- 2.51.0