From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2E8DED2D0FE for ; Tue, 13 Jan 2026 13:26:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=DEAwSb9yqof+c9Garw5rjnnpV/QvVgWVFKuzHYD64x4=; b=m+KnGwxei2IETzULUtQAYfgQ0s K7f6dCAzBlBVffm5vaOfXZyg05vMQLcsFRNHGkIGw4oohCRV3Y2nwVUa4tw+X9LSIwdsehNjwqMm1 VUdFHqS994Wlz8yqZJ/Xsh73DFQhHWwQgLZ8NwvCIBaMOHr7vVEBPu2le4ckH7cNcf4NS9Zi/erTH +cvIUYgor7izXziDjThT6Z8OO+fpnXZJa6r27iRcPTJI4Oezj9mdqEUE9UoN3vqz4kg8BtIGnA87B EZ21pHPgc/JELlnuRjOtaA/DvqUvxMNZIgc2G3xF3EQmu0oCi93lXo6pccvt2lJTWF+Ba8IyJ1vwW 58YvI2YQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vfeQC-000000079qD-2r3u; Tue, 13 Jan 2026 13:26:56 +0000 Received: from tor.source.kernel.org ([2600:3c04:e001:324:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vfeQA-000000079pn-3Th5; Tue, 13 Jan 2026 13:26:54 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id E99D860017; Tue, 13 Jan 2026 13:26:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 08F45C116C6; Tue, 13 Jan 2026 13:26:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1768310813; bh=5eSbp2YejVlQwsJ4Tq8iaUtRuMK3R0vtPTKJ4VgmURA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=PZ0wuhy9YZyNvVi22+zuJIOVkP0qOSxF3UNW2yaaxZbmn9qHW627aYg/NdHLqT+Kj 3qC6OdpuIVsYKkIlh/zuE9bQHG8LXIJ8sAvY8t8ll7TyjiWMIJHh3W8T9qtKAJlD9X JMbnODszUYAWs0x0jwDD0GGhM8dGIj8iUf54gT8poFdNT9QKOSKW+XODF/tFQ95ZgM 826aWti8Ov0pCK1ZnQDPtL3tos/X9RVwDwkEjhCbrd+xBqCgJyd0R9T+evPrlD3ufw Br7yo18JqRrnINxfdLvyNCvTX+JgGdmtLneogsJJAjc96TtI3zmxbcpTGK8T4frOxX u9eusivCcfW9w== Date: Tue, 13 Jan 2026 13:26:49 +0000 From: Simon Horman To: Lorenzo Bianconi Cc: Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, netdev@vger.kernel.org Subject: Re: [PATCH net v2] net: airoha: Fix schedule while atomic in airoha_ppe_deinit() Message-ID: References: <20260105-airoha-fw-ethtool-v2-1-3b32b158cc31@kernel.org> <20260108132218.GG345651@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org On Fri, Jan 09, 2026 at 10:33:55AM +0100, Lorenzo Bianconi wrote: > > On Mon, Jan 05, 2026 at 09:43:31AM +0100, Lorenzo Bianconi wrote: > > > airoha_ppe_deinit() runs airoha_npu_ppe_deinit() in atomic context. > > > airoha_npu_ppe_deinit routine allocates ppe_data buffer with GFP_KERNEL > > > flag. Rely on rcu_replace_pointer in airoha_ppe_deinit routine in order > > > to fix schedule while atomic issue in airoha_npu_ppe_deinit() since we > > > do not need atomic context there. > > > > Hi Lorenzo, > > Hi Simon, > > > > > If I understand things correctly the key problem here is that > > an allocation with GFP_KERNEL implies GFP_RECLAIM and thus may sleep. > > But RCU read-side critical sections are not allowed to sleep in non-RT > > kernels. > > yes, right, RCU section is atomic. > > > > > If so, I think it would be clearer to describe the problem along those > > lines. But maybe it is just me. > > This patch is already in Linus's tree. Yeah, sorry for missing that.