From nobody Mon Feb 9 03:10:46 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 AE5AC31AABC; Sun, 25 Jan 2026 12:24:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769343866; cv=none; b=C1UqEpBvzzs+Ra7P9t2sXVJ2Aps19v3ym3n5CGikukwF5g/AEG8lkt69FCdN6VEB4z8HS+HRNPqGtJEYRHlKwgCNqGcCEIqxjZBbU+Y++AD8beejijixGnwYAqu2PUmXGjKaDXKiotvRpUoBGHjKDYVvBN2SRaTFYcB2MQJ4GNs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769343866; c=relaxed/simple; bh=gnv726bieIdTlpxb8y9dA7re2w8a8XFyqdfDIFSEzHI=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=L7c84d2nASTLPE8TMPA8j+f92OG2Y9pDgeY/KWY68Jmc98Qj0EZtI7pJVNZu54y0WU0pGBum0yBrmZ4xfwUCJRgf/29nmtz8JCanmWzWA6DWncJ1VFaPa/CMQ67boqY6RzMP95VYMUMt9U44YKsK8a0Q+0qDxV00SnEr2POFmIo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=vEURFtES; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="vEURFtES" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A6A88C2BC86; Sun, 25 Jan 2026 12:24:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1769343866; bh=gnv726bieIdTlpxb8y9dA7re2w8a8XFyqdfDIFSEzHI=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=vEURFtESdsmxlAeUG3gPVInNSecoCfaYayLHlBtgID2EzMX89tGwdHiDs6FAbrVZD xA0cXxsk7ovvYL4MeYEtqsvEndg2e2DtZzzXy3DnG4B3Xf+IawWmaeFFLuVc+qyOAh d0ANQav+meFU7NLU6Lq+UcE1Bwf6zhMEOduQ3GUhS4gQLG+KlU5vWtNwaA7XYABcP/ 6fwb3scfeFE8wxPqV4+ee4yodo92idVC0WXwKT1Bgo+Crm/hOlHJlV8IiowRHI207O jqS4bID4uQozT/m94/U6/0AiiSpSLyV2dHsBRUvSYDBGqh+bSXLNQR6GzbSWNDiFt/ enhlA423Ti3ng== From: Jeff Layton Date: Sun, 25 Jan 2026 07:24:13 -0500 Subject: [PATCH v2 1/2] nfsd: add a runtime switch for disabling delegated timestamps Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260125-delegts-v2-1-cd004157fb46@kernel.org> References: <20260125-delegts-v2-0-cd004157fb46@kernel.org> In-Reply-To: <20260125-delegts-v2-0-cd004157fb46@kernel.org> To: Chuck Lever , NeilBrown , Olga Kornievskaia , Dai Ngo , Tom Talpey Cc: linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org, Jeff Layton X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=2421; i=jlayton@kernel.org; h=from:subject:message-id; bh=gnv726bieIdTlpxb8y9dA7re2w8a8XFyqdfDIFSEzHI=; b=owEBbQKS/ZANAwAKAQAOaEEZVoIVAcsmYgBpdgt4zP52FhTzbbyMvLUHQnH3ZXG0FFd/IB7BR of4xMBgPLSJAjMEAAEKAB0WIQRLwNeyRHGyoYTq9dMADmhBGVaCFQUCaXYLeAAKCRAADmhBGVaC Fbs8EACyGS3K6Z0gdhTWiIK4JJGmW9ESMZmgzgjux6uIRqLY4HByur9G0IDRYeISrFDYGYQ2/Le XLqDkFwXsn0snYbzD1H8oUJ1XbUKkHUKj/cdk7LzJxEppnaUaWB/EH0zPdMWoE5C+s8ZwIj2Ke6 C2XyFS9t/xUGNz+rx5ly/2RE/lqXCTJ5MShzZXsdB3lVhmeQlji+vqTTUiLpI5o9LxmkUkuV7lR ReeBkSdPRLfBE+kLh6S/fSPKQKW1acRYg1xayJLuZ3MGO4Oum/H/g13ivB1+Y1dLw4xCtZsrGBW cflf50/RJm4Yoilxy8SJj4NWpOhBgauaUjmvF080yfp0HG1Ye2nz/o9VkW0d2/lR2zAU6K/Zy7x e3UUciK9HZ9BUPzvGKs5ybo/foW4KswIrE1lFxGPtNA1V6mlDJIdjJELPr7S71zDDToKtl4dZgb 2rP+ho07td45GyxTDnM7KvEv7xNlpVXyQ+N6dItLnAPlsgLTsuRQaDznfcYZDJP/ObWjAwaEV1t My+3NvokqNYd0Oh+yT+SL0kH4zkPvQm7Hc2Yju0H3nSqArY6HZGp/++gCQsPPiW8xg+30qr6z7b 0d8LXU8C1V/X84Tz3lDIjbZ6hcFw+0lc/64EJwsvQl6rlNuMQfvZTHSumAfnmgdqzV3WM3uSAAm MP0n2WCD3cX+zuQ== X-Developer-Key: i=jlayton@kernel.org; a=openpgp; fpr=4BC0D7B24471B2A184EAF5D3000E684119568215 The delegated timestamp code seems to be working well enough now that we want to make it always be built in. In the event that there are problems though, we still want to be able to disable them for debugging purposes. Add a switch to debugfs to enable them at runtime. Signed-off-by: Jeff Layton --- fs/nfsd/debugfs.c | 4 ++++ fs/nfsd/nfs4state.c | 4 ++++ fs/nfsd/nfsd.h | 1 + 3 files changed, 9 insertions(+) diff --git a/fs/nfsd/debugfs.c b/fs/nfsd/debugfs.c index 7f44689e0a53edbfd6ade9dda6af4052976a65d3..386fd1c54f5277fd9b9544caa52= 20e234915264d 100644 --- a/fs/nfsd/debugfs.c +++ b/fs/nfsd/debugfs.c @@ -140,4 +140,8 @@ void nfsd_debugfs_init(void) =20 debugfs_create_file("io_cache_write", 0644, nfsd_top_dir, NULL, &nfsd_io_cache_write_fops); +#ifdef CONFIG_NFSD_V4 + debugfs_create_bool("delegated_timestamps", 0644, nfsd_top_dir, + &nfsd_delegts_enabled); +#endif } diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 583c13b5aaf3cd12a87c7aae62fe6a8223368f55..95f2e87141a7ab5dd3da6741859= bdcae28a8c6c0 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -76,6 +76,8 @@ static const stateid_t close_stateid =3D { =20 static u64 current_sessionid =3D 1; =20 +bool nfsd_delegts_enabled __read_mostly =3D true; + #define ZERO_STATEID(stateid) (!memcmp((stateid), &zero_stateid, sizeof(st= ateid_t))) #define ONE_STATEID(stateid) (!memcmp((stateid), &one_stateid, sizeof(sta= teid_t))) #define CURRENT_STATEID(stateid) (!memcmp((stateid), ¤tstateid, size= of(stateid_t))) @@ -6048,6 +6050,8 @@ nfsd4_verify_setuid_write(struct nfsd4_open *open, st= ruct nfsd_file *nf) #ifdef CONFIG_NFSD_V4_DELEG_TIMESTAMPS static bool nfsd4_want_deleg_timestamps(const struct nfsd4_open *open) { + if (!nfsd_delegts_enabled) + return false; return open->op_deleg_want & OPEN4_SHARE_ACCESS_WANT_DELEG_TIMESTAMPS; } #else /* CONFIG_NFSD_V4_DELEG_TIMESTAMPS */ diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h index a2e35a4fa105380c2d99cb0865003e0f7f4a8e8d..7c009f07c90b50d7074695d4665= a2eca85140eda 100644 --- a/fs/nfsd/nfsd.h +++ b/fs/nfsd/nfsd.h @@ -160,6 +160,7 @@ static inline void nfsd_debugfs_exit(void) {} #endif =20 extern bool nfsd_disable_splice_read __read_mostly; +extern bool nfsd_delegts_enabled __read_mostly; =20 enum { /* Any new NFSD_IO enum value must be added at the end */ --=20 2.52.0