From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 80F8A40FD82 for ; Thu, 8 Jan 2026 14:28:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767882507; cv=none; b=RwrYpbyXU1cb63D24Bm8x1WXBIbAiXkg/0MGAHFAG13pt1gs5aF/V3ci8z/1AkfpY8HuZ2mC7sKHIEXgJ+qyS8Y/v1XQxgCFyRz5QxvTMqSzMmIEexMzXQEc5oeC7AzHQg71p3yLTblWIGcFM5+yhIUHXV4LzoCAoKAy1E5ifns= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767882507; c=relaxed/simple; bh=D+97G85jkwq44zug9GC2GyAfPD9MnT1LhuZ3x05qiXQ=; h=From:In-Reply-To:References:To:Cc:Subject:MIME-Version: Content-Type:Date:Message-ID; b=LKoUtuO0BoPdKzoVAKdmSVmA3BUGiJS1fMu0p1xty/l8nZEy3ZteKlM+TuWbMg4DwtbqDoFPCi2AWUmUxEHaYGztWz0qCCCidOlwObklwdzHE9vvL94C6ke5gCToS1kwf0VGzfqxd+3TLcE8S9uk3d+SVUHVdpbyRANtEQqabVY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=UCOREY3r; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="UCOREY3r" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1767882505; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=xNexTqCHVDcVwW22lygltlD6uavxVUzC/ZSbgJIKvGg=; b=UCOREY3rVlHilGJzJUauOzsiaZljnhYpiYtElICeq8NvPb9xrxup31nO9V5IWBjsMsnPxH 8RwbmUsFdfXAqphUIHV20QNKau+rlwR6T1pT5JIeyc65yYJBrlSL87mw9ZyOlAFcaT24rh Q+pWKoNB54fMpxCRmqO7XPOEzokkH9w= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-408-vgsnEQTqPQS65cOOZ6Xy9w-1; Thu, 08 Jan 2026 09:28:22 -0500 X-MC-Unique: vgsnEQTqPQS65cOOZ6Xy9w-1 X-Mimecast-MFC-AGG-ID: vgsnEQTqPQS65cOOZ6Xy9w_1767882500 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 7EE3718005B6; Thu, 8 Jan 2026 14:28:20 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.42.28.4]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id F2FC930002D2; Thu, 8 Jan 2026 14:28:14 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: References: <695e7cfb.050a0220.1c677c.036b.GAE@google.com> <2744142.1767879733@warthog.procyon.org.uk> To: Eric Dumazet Cc: dhowells@redhat.com, syzbot , davem@davemloft.net, horms@kernel.org, kuba@kernel.org, linux-afs@lists.infradead.org, linux-kernel@vger.kernel.org, marc.dionne@auristor.com, netdev@vger.kernel.org, pabeni@redhat.com, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [afs?] [net?] KCSAN: data-race in rxrpc_peer_keepalive_worker / rxrpc_send_data_packet Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <2744875.1767882492.1@warthog.procyon.org.uk> Date: Thu, 08 Jan 2026 14:28:12 +0000 Message-ID: <2744876.1767882492@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 Eric Dumazet wrote: > LGTM, but potential load and store tearing should be avoided, using > READ_ONCE() and WRITE_ONCE(). Fair point. > last_tx_at being time64_t, this would still be racy on 32bit arches. > > last_tx_at could probably be an "unsigned long" (in jiffies units)... I've tried avoiding jiffies where possible. We have way too many different clocks with different granularities and uses in the kernel, but you might be right. David