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 711F374C14 for ; Tue, 10 Mar 2026 00:39:09 +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=1773103149; cv=none; b=HG7LgBQAyap/pDCgAzEQ6kLfBl6jOnJIIL2uS2nWsfF326x0oz1oA/rz+GQCl60fRDfDdjvi0xKdN7WqBHkovyRjzI0L3KHZfLg71sUSAYgwp5loFB9m/Le0yoV/RPdin3O7XFiMBU8C/foJhEz/nxsuMXnmAru1Wy5HyvrOkgo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773103149; c=relaxed/simple; bh=d5ZTjxp9qrV1J2ikD7jMeZdBfSA6ldodNhntJyxDJEs=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=a0qCs7D1tYy50Wg8/Fgnydh/d8wLgFBES4PlVSU/vMqZalYju2U8uAuJFz/JFg3/SawyitkqCBCREMdOUD3db0C0D0PWcWZXxsNDtMpuwe/ZOJLCspJl/D4TPT7qW1J0K89joo+/AIyb6RTyvoRlQQ+6P3Mfr31czz6iXzSCWnk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=JlfXZi6X; 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="JlfXZi6X" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AE1CFC4CEF7; Tue, 10 Mar 2026 00:39:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773103149; bh=d5ZTjxp9qrV1J2ikD7jMeZdBfSA6ldodNhntJyxDJEs=; h=From:To:Cc:Subject:Date:From; b=JlfXZi6XNz43t1w2yTt0kE7fXM/zRi8+mGtvoeXEc2SoavPfoVF+UoS0tHHKpLq8S seYEvQasw5CfPQibr55x0YA3NG5Wmla9tH8MDCcTQTfii4PPRvesVRQAIYyWVmJ07G tkUQHj6Rlu+xoedX7rqiHKyVSBXqJ4yv8VpvxMt3tYkFLlbLHi3i1s0ea0Cz3WDpsZ Q+VfCyAWkcAYaacShljVc6KoKGDE1hDisam2joEDKQBRYhhC5maOahnvQVQ6xkhllY Sol03Bk/iP86hUrhD1wj4x6FP2xmhsqBCJvtYtYEMIwUUvf3ABQJ/abb7y0YP7k5qe K9t143zDp/fgA== From: Jakub Kicinski To: davem@davemloft.net Cc: netdev@vger.kernel.org, edumazet@google.com, pabeni@redhat.com, andrew+netdev@lunn.ch, horms@kernel.org, Jakub Kicinski , Jesper Dangaard Brouer , ilias.apalodimas@linaro.org Subject: [PATCH net v2] page_pool: store detach_time as ktime_t to avoid false-negatives Date: Mon, 9 Mar 2026 17:39:07 -0700 Message-ID: <20260310003907.3540019-1-kuba@kernel.org> X-Mailer: git-send-email 2.53.0 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit While testing other changes in vng I noticed that nl_netdev.page_pool_check flakes. This never happens in real CI. Turns out vng may boot and get to that test in less than a second. page_pool_detached() records the detach time in seconds, so if vng is fast enough detach time is set to 0. Other code treats 0 as "not detached". detach_time is only used to report the state to the user, so it's not a huge deal in practice but let's fix it. Store the raw ktime_t (nanoseconds) instead. A nanosecond value of 0 is practically impossible. Acked-by: Jesper Dangaard Brouer Fixes: 69cb4952b6f6 ("net: page_pool: report when page pool was destroyed") Signed-off-by: Jakub Kicinski --- v2: - make it build v1: https://lore.kernel.org/4e45407b-5c6b-4832-b403-ea62b1e4bcb5@kernel.org CC: hawk@kernel.org CC: ilias.apalodimas@linaro.org --- include/net/page_pool/types.h | 2 +- net/core/page_pool_user.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/include/net/page_pool/types.h b/include/net/page_pool/types.h index 0d453484a585..cdd95477af7a 100644 --- a/include/net/page_pool/types.h +++ b/include/net/page_pool/types.h @@ -247,7 +247,7 @@ struct page_pool { /* User-facing fields, protected by page_pools_lock */ struct { struct hlist_node list; - u64 detach_time; + ktime_t detach_time; u32 id; } user; }; diff --git a/net/core/page_pool_user.c b/net/core/page_pool_user.c index c82a95beceff..ee5060d8eec0 100644 --- a/net/core/page_pool_user.c +++ b/net/core/page_pool_user.c @@ -245,7 +245,7 @@ page_pool_nl_fill(struct sk_buff *rsp, const struct page_pool *pool, goto err_cancel; if (pool->user.detach_time && nla_put_uint(rsp, NETDEV_A_PAGE_POOL_DETACH_TIME, - pool->user.detach_time)) + ktime_divns(pool->user.detach_time, NSEC_PER_SEC))) goto err_cancel; if (pool->mp_ops && pool->mp_ops->nl_fill(pool->mp_priv, rsp, NULL)) @@ -337,7 +337,7 @@ int page_pool_list(struct page_pool *pool) void page_pool_detached(struct page_pool *pool) { mutex_lock(&page_pools_lock); - pool->user.detach_time = ktime_get_boottime_seconds(); + pool->user.detach_time = ktime_get_boottime(); netdev_nl_page_pool_event(pool, NETDEV_CMD_PAGE_POOL_CHANGE_NTF); mutex_unlock(&page_pools_lock); } -- 2.53.0