From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0a-00082601.pphosted.com (mx0a-00082601.pphosted.com [67.231.145.42]) (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 28AA33438BA; Tue, 19 May 2026 18:01:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=67.231.145.42 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779213705; cv=none; b=HchgU0gwAHjffut+QgaZUOEm9tG1xCLTmG+KtLWD0wU6zhlPGjWsDPRHAbWRzoG67A72KkXJDSWwDdguq9Fdjj1Pjteciex0M5r8mv840oFOxBRh6Yj5qvHil3Pmd8FUuhysw/rr0HtXLf1p3v/gUpPKl0ZRD8dAszKOZT3GK48= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779213705; c=relaxed/simple; bh=DvCcxEMfljx0Moile2QWoAeMSvurqlzW6j+wzjUwdmA=; h=From:To:Subject:Date:Message-ID:MIME-Version:Content-Type; b=E9xd3/+lc8CjwbPEH6daQitOUDRQuyKT6MFrcMa9mfcarkxtIwjH0Jot1Vyc1S9p5zjclmTeOdkhQYyrYxZdBfvMYpdbz8UJkaBjdID1Gqo+h84PtuYwdRi1fbF/ppMRBeSKasYd64u6C8kJAd5DmTCdVrPRpyJPr3craSDfbnU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=meta.com; spf=pass smtp.mailfrom=meta.com; dkim=pass (2048-bit key) header.d=meta.com header.i=@meta.com header.b=fmVQ5Hxq; arc=none smtp.client-ip=67.231.145.42 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=meta.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=meta.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=meta.com header.i=@meta.com header.b="fmVQ5Hxq" Received: from pps.filterd (m0528009.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 64J46HRS837486; Tue, 19 May 2026 11:01:39 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=meta.com; h= content-transfer-encoding:content-type:date:from:message-id :mime-version:subject:to; s=s2048-2025-q2; bh=DvCcxEMfljx0Moile2 QWoAeMSvurqlzW6j+wzjUwdmA=; b=fmVQ5Hxqik08kivm5+/PxpU6iG0CTyyGvf 1ezHnxVSSqBrug6O4FwBKpmLCJBBOogJ7QlTNAVAlUULppp5IwgsOEPGeS7p+aiB BkSEiwjJ5QtDhSCUcpfwp8SqVxMZXfV9UVwASx5Avw5qspWL8uouksnPNa5gKVO4 d6MWKDmxWjV5YpSxhS1yGrcxy1JyqAYrp9xNR3BwEqu3VZ/LKOIPziHzwSF67/FN CZEUs3SIeY7mI7+umPRmBXjpqYDVCI68mO0FFWWlpq99gqPt61EsAZv7AhrcGTSc AS5JhmrriTBcLU7znQveZos7oBHll2YBMHj/SjP1m1PkEJPFfZ2Q== Received: from mail.thefacebook.com ([163.114.134.16]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 4e7ab5eaum-2 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT); Tue, 19 May 2026 11:01:39 -0700 (PDT) Received: from devbig003.atn7.facebook.com (2620:10d:c085:108::150d) by mail.thefacebook.com (2620:10d:c08b:78::2ac9) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.2.2562.37; Tue, 19 May 2026 18:01:37 +0000 From: Chris Mason To: Chuck Lever , Jeff Layton , "J. Bruce Fields" , Trond Myklebust , , Subject: [PATCH] nfsd: drain backchannel callbacks before freeing a session Date: Tue, 19 May 2026 10:49:13 -0700 Message-ID: <20260519180032.1852793-2-clm@meta.com> X-Mailer: git-send-email 2.52.0 Precedence: bulk X-Mailing-List: linux-nfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-Authority-Analysis: v=2.4 cv=XNQAjwhE c=1 sm=1 tr=0 ts=6a0ca583 cx=c_pps a=CB4LiSf2rd0gKozIdrpkBw==:117 a=CB4LiSf2rd0gKozIdrpkBw==:17 a=NGcC8JguVDcA:10 a=VkNPw1HP01LnGYTKEx00:22 a=7x6HtfJdh03M6CCDgxCd:22 a=U_y8lYiYyhHBU5rMqhb2:22 a=VabnemYjAAAA:8 a=-0hxeGBmMInBsXaKhxMA:9 a=gKebqoRLp9LExxC7YDUY:22 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNTE5MDE3OSBTYWx0ZWRfXy5Yma67Z9AFp +6xYI3vid/3H5bUoE8OAfOrRZdY4O23Eg7lMqIoOJx5vWLyTnZeKOaXk7gH+MBCjq5FH0L2YRH/ vftSJdbhuXYxTqQOEDI6FAoS7CrrWhmy9pfvWuY475w6IMQHaWMMrYqWYp6+9buGPnHZ/IbZY2Q zsJuUO7VrqtBaPOvMDZJ3EhzEYfLytUK9Tnc6RzVJFGg7nbR8EkVj5d2AoIDHef7gLQzlYDwjm5 yQ9t4c8Ro74TulP6vpEZg5FVnqn0kWkJqdZXU72PXkEU6G0EprOnwjl/Pc/rOlzy6W1MlMx4wha xiznAg1xCC7+ekdFIE33IgF9WWoQetes4mBlO9lpXuTpSj7dSloOy3sOTt1TlgQJmIKmwhfkY9v G7+NKyNyocrIRVKlSby3r4aGxF8kP/5TX3sZXTI19iqUMGE7yUFyFF5Zxbm4VKtKsOlwt6m3PMr F7c0OQk9tKbJSEUn6wQ== X-Proofpoint-ORIG-GUID: iRfZGVroGzAegL-RzzXU3F0czknGYqBy X-Proofpoint-GUID: iRfZGVroGzAegL-RzzXU3F0czknGYqBy X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-05-19_05,2026-05-18_01,2025-10-01_01 DESTROY_SESSION can free an nfsd4_session while a backchannel callback for the same client is still live on rpciod, leaving clp->cl_cb_session as a dangling pointer. The first patch waits on cl_cb_inflight, and the second hopes to make things harder to regress in the future by dropping a NULL in there. Signed-off-by: Chris Mason