From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f169.google.com (mail-pf1-f169.google.com [209.85.210.169]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5F76647DD5F for ; Wed, 29 Jul 2026 12:07:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.169 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785326873; cv=none; b=CCL8KnJsJcwQZABVyFfjp7s+WysgdwAFhVlz9VulVMGbD9QxqtA8lS5WNKKZNk1I4O/5/hsN5AZo+zz1W/cpUS3XrLl29xpnNUyIKnhefMLaXkKB0F880JR0yv4zuP4agSxkAqwo5nyAXzmF09t01ffsgXqUTbVY4XAQL7aGa/8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785326873; c=relaxed/simple; bh=T4d/PEXZNs6ifbkGXcXMa8zZC7Ih8RIE41MHYVn0pWk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=BZWrlRRa4lFKFr8LbUCg35UgvOXP+AP/JBu6espJgIyvFOWzHirlp0P2m3NevyQjE4YOYQAbkX9g87pxrtyC5AFq4qEOhaiQnoqRWPwt3uvEgYwNG2avH5zOzkO57EM0NV2zYAhW/h41FCTn9tn4pBnKmkYTvK6a/0bctZ/13XI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=PNt+XKOn; arc=none smtp.client-ip=209.85.210.169 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="PNt+XKOn" Received: by mail-pf1-f169.google.com with SMTP id d2e1a72fcca58-84a2dcede83so1115115b3a.3 for ; Wed, 29 Jul 2026 05:07:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1785326871; x=1785931671; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:sender:from:to:cc:subject:date :message-id:reply-to:content-type; bh=WVlBM8baZnY3XWsIGKCw1XL7pOs30aO7ASNtPvRepdA=; b=PNt+XKOnhX/EPNNCiBWo8RTgiHhweWM5g6HHyheIX5827OmSahCH1U5lg3X41gmoSI svTtJ8MeUaeINtqbS65xAA/+cQ8HDnYG6Ted+J8SZLvg6G20Zww3qCJZI8XZUExMJ557 ivYXe4NSWWMWvd4TorjlTx+Jka12+urAHBn/f6593+uzbvXlWfUpmLhBkfBNLHRxR1hq DSHr+B7CNVAYRH+kyGn5XLhZKyc6x/KrhdPLdU/uzE8zkUr1wwUYxF2U+kFIu8ozgRED n9HpP9azBN6lpIJm4zyeXiYcGlKueEjJ4lnrIx9fETtQSIYS8JkyHj9LThqTQQUIVEch LoAg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1785326871; x=1785931671; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:sender:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=WVlBM8baZnY3XWsIGKCw1XL7pOs30aO7ASNtPvRepdA=; b=abaP3amrA3ZvKEPvKv7exBE8xJqnnf8aJ0cZxszkB1RqI3aH9nKth4w1AIxxbA5U9x trQHoSmy6dFM9SHtY2Zl4dnraTCb252Kj77BZuBM537LR3kNnMx5UJSldlbGv543YyAF qwoHFJgSQnkTTVzDxSIoMoBOdvfGC4s8PumW2dyFua4bxUt2pbwqJWAtS9Yn06EF5YvP iFvxj/vTeaAE+qgzYkHS6Kxq0QXGqtfrPrCXdlb09Z4cnyLo0tbqixZHZnYZi4mJN599 vNzBuFDDgj29hJ9Lvy2+mos/72Vs+FfRAgO8OvTctiTKo0Q81xwLLRjGpiVqglu985Uz hAjA== X-Forwarded-Encrypted: i=1; AHgh+RoZUWlkb/JVSGTznMgzuTT3cabcujcmTTB+E1Y6NVE8CduFqP1mvFLdjGRDKO/b+4l9dQ+R51rYlLKKFXE=@vger.kernel.org X-Gm-Message-State: AOJu0YxKhDYeGLjsys9EQOeh3fqnspU/fy2b46QS8gdUoyARwe8rj3kk 8dXtEtNOBO2GwFve5oFKbq68USRDX1OSwOr6NuG/Xd7LO7D15fj1QfEz X-Gm-Gg: AR+sD12c23avA2a/qsl+X/NLrUTKUUEFIEzj7KofR6LVsR0Vn+zAqhjjN/nNx5SMKur fhWBKf6I2YGHp+vPQbZUhMWV6D4MSL0fV8qDJgSivBNcAnNBp70/RhY0koHqtGFkr7yfGS1VExG F1gYMq320entZRQtsV4YMFPU0/eJGOeM0x5Xkcd0YUxdU5az1qIyx2SoxCEqv+IgGzZtUTsncmJ UyqSpgDM21sXLzTQIgxnFBV9nbmTo0oCHCZ4bk7cMcMOCyWWa2xWeWFv+ElJW+1MJXrhheOdxNl nRetMF20FcYusfdZB9usVfzWH5RrTFLOYaSM7CZCoOvnnRoiIbFl6U/pFizWYaZ1qfKIds37ASc CClViNKfzs7tUfHPeXYQmZJOtepPJvpVW0W5TOaA9lJeVQkDmt5MWDn4jO4TQgtTEzTuSgREH4q xGCmDqCdn51dtvE1R4UAq56PG2hHd4C4wWzmzPPqibvwLg+gPh4baKgXMog68Ul6zrc0ilQYI5v 3D7dTmyt/3aO9eBim9JXcEp/6JIn6W1Q3PBjA== X-Received: by 2002:a05:6a00:94d6:b0:847:8b11:5966 with SMTP id d2e1a72fcca58-84e931b4c84mr7075564b3a.1.1785326870437; Wed, 29 Jul 2026 05:07:50 -0700 (PDT) Received: from m-upc-A520M-HDV.lan ([2400:2410:3f60:500:c705:d3b3:a6d9:8512]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-84ea0300ac2sm1263482b3a.35.2026.07.29.05.07.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 29 Jul 2026 05:07:49 -0700 (PDT) Sender: Yuyang Huang From: Yuyang Huang To: Yuyang Huang Cc: "David S. Miller" , Bobby Eshleman , Chris J Arges , David Ahern , David Wei , Dimitri Daskalakis , Donald Hunter , Eric Dumazet , Gal Pressman , Ido Schimmel , Jakub Kicinski , Paolo Abeni , Shuah Khan , Simon Horman , Stanislav Fomichev , Willem de Bruijn , linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCH net-next v4 01/10] ipv6: add ip6_del_rt_reason() Date: Wed, 29 Jul 2026 21:07:30 +0900 Message-ID: <20260729120739.47880-2-sigefriedhyy@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260729120739.47880-1-sigefriedhyy@gmail.com> References: <20260729120739.47880-1-sigefriedhyy@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Add RTA_DEL_REASON and enum rta_del_reason to the rtnetlink uAPI, and add ip6_del_rt_reason(), which takes the reason a route is being deleted. ip6_del_rt() becomes a wrapper that passes RTA_DEL_REASON_UNSPEC, so its callers do not change. The reason is unused for now. Subsequent patches propagate it to the deletion path and report it on RTM_DELROUTE. Signed-off-by: Yuyang Huang --- include/net/ip6_route.h | 9 +++++++++ include/uapi/linux/rtnetlink.h | 17 +++++++++++++++++ net/ipv6/route.c | 8 +++++++- 3 files changed, 33 insertions(+), 1 deletion(-) diff --git a/include/net/ip6_route.h b/include/net/ip6_route.h index 09ffe0f13ce7..92ad5a0d03a2 100644 --- a/include/net/ip6_route.h +++ b/include/net/ip6_route.h @@ -128,12 +128,21 @@ int ip6_route_add(struct fib6_config *cfg, gfp_t gfp_flags, int ip6_ins_rt(struct net *net, struct fib6_info *f6i); #if IS_ENABLED(CONFIG_IPV6) int ip6_del_rt(struct net *net, struct fib6_info *f6i, bool skip_notify); +int ip6_del_rt_reason(struct net *net, struct fib6_info *f6i, bool skip_notify, + enum rta_del_reason del_reason); #else static inline int ip6_del_rt(struct net *net, struct fib6_info *f6i, bool skip_notify) { return -EAFNOSUPPORT; } + +static inline int ip6_del_rt_reason(struct net *net, struct fib6_info *f6i, + bool skip_notify, + enum rta_del_reason del_reason) +{ + return -EAFNOSUPPORT; +} #endif void rt6_flush_exceptions(struct fib6_info *f6i); diff --git a/include/uapi/linux/rtnetlink.h b/include/uapi/linux/rtnetlink.h index 27265fd31e5f..fe00e624f3c3 100644 --- a/include/uapi/linux/rtnetlink.h +++ b/include/uapi/linux/rtnetlink.h @@ -399,6 +399,7 @@ enum rtattr_type_t { RTA_DPORT, RTA_NH_ID, RTA_FLOWLABEL, + RTA_DEL_REASON, __RTA_MAX }; @@ -407,6 +408,22 @@ enum rtattr_type_t { #define RTM_RTA(r) ((struct rtattr*)(((char*)(r)) + NLMSG_ALIGN(sizeof(struct rtmsg)))) #define RTM_PAYLOAD(n) NLMSG_PAYLOAD(n,sizeof(struct rtmsg)) +/* RTA_DEL_REASON: why the kernel deleted the route. u32. + * Emitted only on RTM_DELROUTE notifications, and only when the deletion + * path records a cause. Absence means either an older kernel or a + * deletion path that does not (yet) record its cause - consumers must + * treat "absent" and "unspec" identically. New causes may be appended. + * Currently only IPv6 deletion paths record a cause. + */ +enum rta_del_reason { + RTA_DEL_REASON_UNSPEC, /* cause not recorded */ + RTA_DEL_REASON_EXPIRED, /* RTF_EXPIRES lifetime ran out (GC) */ + RTA_DEL_REASON_RA_WITHDRAWN, /* zero-lifetime RA / PIO / RIO */ + __RTA_DEL_REASON_MAX +}; + +#define RTA_DEL_REASON_MAX (__RTA_DEL_REASON_MAX - 1) + /* RTM_MULTIPATH --- array of struct rtnexthop. * * "struct rtnexthop" describes all necessary nexthop information, diff --git a/net/ipv6/route.c b/net/ipv6/route.c index a1301334da48..9f82829923ab 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -3994,7 +3994,8 @@ static int __ip6_del_rt(struct fib6_info *rt, struct nl_info *info) return err; } -int ip6_del_rt(struct net *net, struct fib6_info *rt, bool skip_notify) +int ip6_del_rt_reason(struct net *net, struct fib6_info *rt, bool skip_notify, + enum rta_del_reason del_reason) { struct nl_info info = { .nl_net = net, @@ -4004,6 +4005,11 @@ int ip6_del_rt(struct net *net, struct fib6_info *rt, bool skip_notify) return __ip6_del_rt(rt, &info); } +int ip6_del_rt(struct net *net, struct fib6_info *rt, bool skip_notify) +{ + return ip6_del_rt_reason(net, rt, skip_notify, RTA_DEL_REASON_UNSPEC); +} + static int __ip6_del_rt_siblings(struct fib6_info *rt, struct fib6_config *cfg) { struct nl_info *info = &cfg->fc_nlinfo; -- 2.43.0