From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-yb1-f176.google.com (mail-yb1-f176.google.com [209.85.219.176]) (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 37BA8145348 for ; Sun, 6 Jul 2025 14:10:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.219.176 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751811020; cv=none; b=OfUiAxvr1znCj5rfJD/2E+WrI/JnC+RqgMKn/+RC50iiT8vpoxJxseNcyzMEEF6SNO9OkLkQY7wircgwzdMjdGDUQFjKD+FlIBqZHJWarFeDHE/8X+8yvUaQUaFVmHXJHQdvacEzKd3pagygzf7q5y1IOyEhJtwrlxtq8pK0Svs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751811020; c=relaxed/simple; bh=3ZLmOPQGHXtaSCTMyWzrwHpD+JeYJ8AhR0F8iLpTs1M=; h=Date:From:To:Cc:Message-ID:In-Reply-To:References:Subject: Mime-Version:Content-Type; b=Wd/LtA3Fd1n2iu3cs/Irc0UP1nIrXrxAZ3LqHZL2zluhGC9WZvpLIXTLGIpYMnoM/BTbMQaQyWdvzzurnLcL6XiVjBLPjr8+swc3F8uTT33ffLylZSN11Mu3wNSdB+uGDBXgIw5S0oR4kEv9QVMJTiJxZXVrrWB3TnPSWyeP2zc= 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=EeQfykwu; arc=none smtp.client-ip=209.85.219.176 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="EeQfykwu" Received: by mail-yb1-f176.google.com with SMTP id 3f1490d57ef6-e73e9e18556so2083880276.0 for ; Sun, 06 Jul 2025 07:10:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1751811018; x=1752415818; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:subject:references :in-reply-to:message-id:cc:to:from:date:from:to:cc:subject:date :message-id:reply-to; bh=qlWWRCxTqEArF/ZxA6ho8LHXX7FoEY4n7jhzI24fGbE=; b=EeQfykwuhoUAiAxSiWlTC3U4nzyQawxgmuqwbwFxTC9jlcnWmoUyXrKRw2qmohu1uZ nj1bP6RDULtrCy/i3b9JWfBzrnAAHgavCuLr4zmIB6oL4H9QeaI8S7cwUskhiDr+IJpQ A8wj1ZNGP0n97fsZLke34XnwUA6bfAVUyycnoks4zwSWnNDh8q7x+s1NsjO/DECi7fQs VR1rGs5d4Oia8Bx52YwiRDgx5Vbh1O21+MQSzy7AsjqJnIyIwuF+CA+rbwvbG7fySKO6 YY8QusS94eSqWqGFJWkQn1zhZd4NJP4nCi7caySrVQwqCcqFKdpRg5SALD1/WJjd2nb2 /eyQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1751811018; x=1752415818; h=content-transfer-encoding:mime-version:subject:references :in-reply-to:message-id:cc:to:from:date:x-gm-message-state:from:to :cc:subject:date:message-id:reply-to; bh=qlWWRCxTqEArF/ZxA6ho8LHXX7FoEY4n7jhzI24fGbE=; b=EysCfVEPauRXoVtPG47FIlQ+/UWpnetwwQB9r1mRJ6YbbsXDos4tLZfzlxB9DjxFHh E50pLZmv5VNDTQAOJNabDMF9aotU3ohUAxoBLjDDMk3zdKRmu7TVgJfo3HNzqev6NuEU +0E59WlTh7bPCY2OClXM2EU5KOdl3bPByJOVHQXNAOo54nAsdmZ5Nz56B3nsaFTZ7Jk3 GmqnW9n8Ek28GKtjIuy8kzKMG8Xti30ruBugCFeyFXadjip3DFuIbZcH0e461ZaekzZW 8sMjozybUkxExRC/rE+9gRGWIaya6zVPO0BkCJm/9gUW2u2GqadXtyZacSauDeEYwp78 VOoA== X-Forwarded-Encrypted: i=1; AJvYcCWqLcw7CoOq3EILHHaJTyIqHSnmNNBcSUcCoJJRJCFdwx/aNfgGIoL3MwzA05QtX+Q0LPRHAPY=@vger.kernel.org X-Gm-Message-State: AOJu0YzFr4eI29CQep9U5aIdCHRkc817qCsZ/H7ppciBAvnAiBBMsX+3 76U0DU4VEermb61Z7v+J5VEs8I4gz+b3GCz/8m1XxWmGRe3RYwzq4dNG X-Gm-Gg: ASbGnctRKWRq+Q7nxi7XxhC84GYDuK88Ev6MvdqlKnKR5z/Ypc+TGTtrfsUDr/EMsnj LvJLls5XK2YT2WjhRvqvOn0KxB9VukG26hkffar80wwlkVPwF6pMnHLYC9waI+Yffb/16eYULL/ B9dEiydIUpdbM6cI9RclXvWFAKnuFTNFdBQX6OYYOMwGbBW+dEhSlFl9ZpHkekSdqv/CsXwME8T nsszdGciFLaXKBogelcKefrb3sRWsplM30Xy2F5tx35rppPzCoxYCyFFzTTsYvAoCCPJQzvja9s KLx0pazTSNrWAfJZt06HYW+Cx+t8bAb7BXk+85SAd1/0xY4+1khdl+2ncREMBCT9TCUFyNxxl8c zvx0j7StFOaDRLdTsDTGnf5IWMqQBGorxZxLy1tE= X-Google-Smtp-Source: AGHT+IGZeFZ1v1Z9Q5l9GllphahCGMZ5CRccDSLJmoQmj2o8FzOaE529ayzde9A+47UtLx02Qca+ow== X-Received: by 2002:a05:6902:154c:b0:e81:566c:3085 with SMTP id 3f1490d57ef6-e899d057e47mr11179278276.1.1751811018171; Sun, 06 Jul 2025 07:10:18 -0700 (PDT) Received: from localhost (234.207.85.34.bc.googleusercontent.com. [34.85.207.234]) by smtp.gmail.com with UTF8SMTPSA id 00721157ae682-7166598b418sm12373787b3.11.2025.07.06.07.10.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 06 Jul 2025 07:10:17 -0700 (PDT) Date: Sun, 06 Jul 2025 10:10:17 -0400 From: Willem de Bruijn To: Kuniyuki Iwashima , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: Simon Horman , Kuniyuki Iwashima , Kuniyuki Iwashima , netdev@vger.kernel.org Message-ID: <686a83c9444b3_3aa654294e@willemb.c.googlers.com.notmuch> In-Reply-To: <20250702223606.1054680-2-kuniyu@google.com> References: <20250702223606.1054680-1-kuniyu@google.com> <20250702223606.1054680-2-kuniyu@google.com> Subject: Re: [PATCH v1 net-next 1/7] af_unix: Don't hold unix_state_lock() in __unix_dgram_recvmsg(). Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Kuniyuki Iwashima wrote: > When __skb_try_recv_datagram() returns NULL in __unix_dgram_recvmsg(), > we hold unix_state_lock() unconditionally. > > This is because SOCK_SEQPACKET sk needs to return EOF in case its peer > has been close()d concurrently. > > This behaviour totally depends on the timing of the peer's close() and > reading sk->sk_shutdown, and taking the lock does not play a role. > > Let's drop the lock from __unix_dgram_recvmsg() and use READ_ONCE(). > > Signed-off-by: Kuniyuki Iwashima Reviewed-by: Willem de Bruijn