From nobody Thu Oct 2 19:24:07 2025 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 B73313074A6; Fri, 12 Sep 2025 11:55:26 +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=1757678126; cv=none; b=LPu4buKyMkO/KJsuLR3WTwfjxBCFbFlBPzpBr/XxH7TJrx4xmLNqBAzcsmkyANFe8RIWe7SPI5Taxk8ZTSzEkP2MLIdhAH7R6/vrC1eVf/Xt3dNOiAZhmJN2hlRhT2jSFysOi8i0lD29PqLzzvJa7ARFIN23fqcQxwm8rOhWU2M= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757678126; c=relaxed/simple; bh=De4ojnwgkm9eMqqPSKyIiyLz23QqFGKtmyVxTIjNLfQ=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=TzxUrVfKuSEd5HGcMarDK0119RJSHLvDPLgG1fl7Lwtx1RGvu0wFS5nUKlL7hLSIZ6ImO0lJsEBLjMFLebDQ2CiWztmuAUoVZx04az5KZkj2TZv6ZS0tNN/0VzYlEllBCIleUo1pmeyD1dBmZnywT47jr1hwuGdqU0qrm2NeZjc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=JTURILdJ; 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="JTURILdJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CA131C4CEF1; Fri, 12 Sep 2025 11:55:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1757678126; bh=De4ojnwgkm9eMqqPSKyIiyLz23QqFGKtmyVxTIjNLfQ=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=JTURILdJEmUAkvarf7UQC84aYm10rNqAw5HpdHjauWZLfC0GrHmQearLU5fScYn+y V2oBasrmX3kOTVFo9pnBHmb44R/gj+FRboyQvULGBvrfpxekF2o9Uvtuc3o+2cP8SW x1WlJrz+OTG0eaMNTm+tA0TxVmItm9CEEzOaPepi8FmVF7qxF7m89yzwKL5bibMTEK roI6rn/NVqGAlYyCi9B4VdOZSxLkS0O8R26DG37srP0Eilc8Ncnw6BRg5Fm1Gmys1n gJ+IHHJcznIQK8mlmF5jI6MABZE35fT94bw6+wLIckgZlzUzxzXXQUtgGzCXqAqbIR G7DD/I+kCH1wQ== From: Christian Brauner Date: Fri, 12 Sep 2025 13:52:48 +0200 Subject: [PATCH v2 25/33] uts: support ns lookup Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20250912-work-namespace-v2-25-1a247645cef5@kernel.org> References: <20250912-work-namespace-v2-0-1a247645cef5@kernel.org> In-Reply-To: <20250912-work-namespace-v2-0-1a247645cef5@kernel.org> To: Jan Kara , Amir Goldstein , linux-fsdevel@vger.kernel.org Cc: Josef Bacik , Jeff Layton , Mike Yuan , =?utf-8?q?Zbigniew_J=C4=99drzejewski-Szmek?= , Lennart Poettering , Daan De Meyer , Aleksa Sarai , Alexander Viro , Jens Axboe , Tejun Heo , Johannes Weiner , =?utf-8?q?Michal_Koutn=C3=BD?= , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Chuck Lever , linux-nfs@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, netdev@vger.kernel.org, Christian Brauner X-Mailer: b4 0.14.3-dev-385fa X-Developer-Signature: v=1; a=openpgp-sha256; l=1513; i=brauner@kernel.org; h=from:subject:message-id; bh=De4ojnwgkm9eMqqPSKyIiyLz23QqFGKtmyVxTIjNLfQ=; b=owGbwMvMwCU28Zj0gdSKO4sYT6slMWQc4Zz6modrmXDq9G1+zmmCz/3XLI0SUudUEOHMKDzMV qGpcfxtRykLgxgXg6yYIotDu0m43HKeis1GmRowc1iZQIYwcHEKwET+hTMyfLDoWDnfdUa2KrtR pYdvXfGMs/WKRjIC3S19q3xK7SKYGP5wBq6Qqrrjv1Kx5Pems772n5bK3nBe+k1y79Vs0Ss9jiI 8AA== X-Developer-Key: i=brauner@kernel.org; a=openpgp; fpr=4880B8C9BD0E5106FC070F4F7B3C391EFEA93624 Support the generic ns lookup infrastructure to support file handles for namespaces. Signed-off-by: Christian Brauner Reviewed-by: Jan Kara --- kernel/utsname.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/kernel/utsname.c b/kernel/utsname.c index 02037010b378..64155417ae0c 100644 --- a/kernel/utsname.c +++ b/kernel/utsname.c @@ -13,6 +13,7 @@ #include #include #include +#include #include =20 static struct kmem_cache *uts_ns_cache __ro_after_init; @@ -58,6 +59,7 @@ static struct uts_namespace *clone_uts_ns(struct user_nam= espace *user_ns, memcpy(&ns->name, &old_ns->name, sizeof(ns->name)); ns->user_ns =3D get_user_ns(user_ns); up_read(&uts_sem); + ns_tree_add(ns); return ns; =20 fail_free: @@ -93,10 +95,12 @@ struct uts_namespace *copy_utsname(unsigned long flags, =20 void free_uts_ns(struct uts_namespace *ns) { + ns_tree_remove(ns); dec_uts_namespaces(ns->ucounts); put_user_ns(ns->user_ns); ns_free_inum(&ns->ns); - kmem_cache_free(uts_ns_cache, ns); + /* Concurrent nstree traversal depends on a grace period. */ + kfree_rcu(ns, ns.ns_rcu); } =20 static inline struct uts_namespace *to_uts_ns(struct ns_common *ns) @@ -162,4 +166,5 @@ void __init uts_ns_init(void) offsetof(struct uts_namespace, name), sizeof_field(struct uts_namespace, name), NULL); + ns_tree_add(&init_uts_ns); } --=20 2.47.3