From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 70C18335BBB; Fri, 4 Sep 2026 05:45:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788500746; cv=none; b=ql5j7hNUeprvheQEae3W6EcETFDyzYNG921dRdZ+ii0ffBjcegb6vvNCyPiPSBdTnmapnZYRs+wLCrLg2NEwNP2/HSaEDnl6KqEsxB6xPaZny4Xi0ebrx8hGHO1u4GBWcw72AD2khMxXWiFefgxJ4kQRafdR9x41ca21FIutlKs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788500746; c=relaxed/simple; bh=qoDcXWmAYAkUP5elpOj3gsOw3DaMFWt+MLL+iC2B6gg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=jFoVUKbD9usjFRx30wnZKoBMB31x137BXGoyyxNVNTOktmnYq6eFFTWq5K3BTYSwYc1zv1z7sYZDNCkRoZgj0CCP/V6gdoCEtQjPrCO6SOJcex9MMW1F07Dmng8dOL2aALy3Rg5ty6tvAZnaCNTXVO5n1oUkHFFo4ynK/6y5nj0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=iv0/BM0z; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="iv0/BM0z" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C85071F00A3D; Fri, 4 Sep 2026 05:45:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788500745; bh=gfuPmUVXTgINs7Y/+fZDJVdPvTetKcZ3SlfDHIFFTyk=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=iv0/BM0z0AjokVVugjnUdgY7DjQwZLD+hNUDb7YcIJ38GGx2ceDS4ijGkiCf+3yVC cVFXAFXfzW8mxT+K75SU2YBdbbv83bLF1+ctI08oHYhcm9rCENR9XFOwcwweQtsW5y Isu22WFk6+hrd5O1pqZ439SU4NCHHUqX+iMHz6Kw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jeff Layton , Chuck Lever Subject: [PATCH 6.18 122/552] nfsd: clear CALLBACK_RUNNING on failed delegation recall queue Date: Fri, 4 Sep 2026 06:54:39 +0200 Message-ID: <20260904045750.849947727@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260904045747.813364717@linuxfoundation.org> References: <20260904045747.813364717@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jeff Layton commit b036727d334b1b7cd4c1f1fba3b59ba93a6bbe96 upstream. nfsd_break_one_deleg() sets NFSD4_CALLBACK_RUNNING via test_and_set_bit at entry to serialize recall work, then calls nfsd4_run_cb() to queue the recall. When the queue attempt fails the refcount bump is undone, but the RUNNING bit is left set. The only site that clears the bit is nfsd41_destroy_cb() (fs/nfsd/nfs4callback.c), which runs from the workqueue and is therefore unreachable when nothing was queued. The bit becomes a permanent latch on dp->dl_recall.cb_flags: every subsequent break_lease() on the same delegation hits the early-return guard in nfsd_break_one_deleg() and silently skips the recall, so the delegation is never broken and the conflicting open or lock stalls. Fix by clearing NFSD4_CALLBACK_RUNNING on the !queued branch alongside the refcount_dec. Fixes: 1054e8ffc5c4 ("nfsd: prevent callback tasks running concurrently") Cc: stable@vger.kernel.org Signed-off-by: Jeff Layton Link: https://patch.msgid.link/20260526-cb_recall_any_callback_running_stuck-v1-2-310011a028f3@kernel.org Signed-off-by: Chuck Lever Signed-off-by: Greg Kroah-Hartman --- fs/nfsd/nfs4state.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -5516,8 +5516,10 @@ static void nfsd_break_one_deleg(struct refcount_inc(&dp->dl_stid.sc_count); queued = nfsd4_run_cb(&dp->dl_recall); WARN_ON_ONCE(!queued); - if (!queued) + if (!queued) { refcount_dec(&dp->dl_stid.sc_count); + clear_bit(NFSD4_CALLBACK_RUNNING, &dp->dl_recall.cb_flags); + } } /* Called from break_lease() with flc_lock held. */