From mboxrd@z Thu Jan 1 00:00:00 1970 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 C7B8932D0DF for ; Thu, 27 Nov 2025 11:45:02 +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=1764243902; cv=none; b=LOaorkGEfkOoghV3/GlVF4XWKAz/gwcCNOYIZEL+25Djv5JyMbTnrD6rUAov4krZ7/CIelTvtThkuH04/fQl/Agt1QZOYfhE76t8dCnsVSN+fWQf3phSMCdraFCb0maPtLzrFtLfBMz3T10BEnvhVz3m0YCgMlBzxNSE5C/5Svg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764243902; c=relaxed/simple; bh=bhEiLZJrUMZE5RAfsENKBxd0m7eM54hwM9QpdUvUm44=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=UWduPJyFMW5LRiAub4y9xllS7I5SXdbJhRMDwctRfpT4I0td2sMns8aJzmYAkaq7DHE/9HphwctSkFwd+K5o6zZhgKUCh0jxZtHdf9dElns5uj7RNiELNrk4Zre8O4NL9dwpynucHVd9U120YN5n+uC0pT+n5U1Sie1zMiOY9xQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=QHp8Wbcu; 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="QHp8Wbcu" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E18DBC4CEF8; Thu, 27 Nov 2025 11:45:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1764243902; bh=bhEiLZJrUMZE5RAfsENKBxd0m7eM54hwM9QpdUvUm44=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=QHp8WbcuOlkfl9aApJ2sX4htFuk9y4kYsjirnlH9RFfdwzGWCW5H+yTllSh1QQZAM q+CJz8eiHUg09XWsp3N1R+iO+FemrSz9Azi3hPVHzsbNRTSZ2WWf/kX4vpfR0LYUpi ZE3I4NtTABE98WcpfcMVwOe1wO/b3GflE9FY7y+Z4IGyPwCel29aX/7Sqj43+/ZZXa R/NVh144ENx0Jgc+UcrAtWEsmHQu7YbqWx+0jd1eERRD4qB6Kd+10LS14JFGJClfql RA62517drMCuRjOZqtRw+OHcUEeb+6SDJngBKajgmV4fAhtakpcLoxGIClo9pl2Mcb OHl4PjlJUxAXQ== Date: Thu, 27 Nov 2025 11:44:58 +0000 From: Simon Horman To: Sreedevi Joshi Cc: intel-wired-lan@lists.osuosl.org, netdev@vger.kernel.org, Sridhar Samudrala , Emil Tantilov , Aleksandr Loktionov , Paul Menzel Subject: Re: [PATCH iwl-net v2 1/3] idpf: Fix RSS LUT NULL pointer crash on early ethtool operations Message-ID: References: <20251124184750.3625097-1-sreedevi.joshi@intel.com> <20251124184750.3625097-2-sreedevi.joshi@intel.com> 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-Disposition: inline In-Reply-To: <20251124184750.3625097-2-sreedevi.joshi@intel.com> On Mon, Nov 24, 2025 at 12:47:48PM -0600, Sreedevi Joshi wrote: > The RSS LUT is not initialized until the interface comes up, causing > the following NULL pointer crash when ethtool operations like rxhash on/off > are performed before the interface is brought up for the first time. > > Move RSS LUT initialization from ndo_open to vport creation to ensure LUT > is always available. This enables RSS configuration via ethtool before > bringing the interface up. Simplify LUT management by maintaining all > changes in the driver's soft copy and programming zeros to the indirection > table when rxhash is disabled. Defer HW programming until the interface > comes up if it is down during rxhash and LUT configuration changes. > > Steps to reproduce: > ** Load idpf driver; interfaces will be created > modprobe idpf > ** Before bringing the interfaces up, turn rxhash off > ethtool -K eth2 rxhash off > > [89408.371875] BUG: kernel NULL pointer dereference, address: 0000000000000000 > [89408.371908] #PF: supervisor read access in kernel mode > [89408.371924] #PF: error_code(0x0000) - not-present page > [89408.371940] PGD 0 P4D 0 > [89408.371953] Oops: Oops: 0000 [#1] SMP NOPTI > > [89408.372052] RIP: 0010:memcpy_orig+0x16/0x130 > [89408.372310] Call Trace: > [89408.372317] > [89408.372326] ? idpf_set_features+0xfc/0x180 [idpf] > [89408.372363] __netdev_update_features+0x295/0xde0 > [89408.372384] ethnl_set_features+0x15e/0x460 > [89408.372406] genl_family_rcv_msg_doit+0x11f/0x180 > [89408.372429] genl_rcv_msg+0x1ad/0x2b0 > [89408.372446] ? __pfx_ethnl_set_features+0x10/0x10 > [89408.372465] ? __pfx_genl_rcv_msg+0x10/0x10 > [89408.372482] netlink_rcv_skb+0x58/0x100 > [89408.372502] genl_rcv+0x2c/0x50 > [89408.372516] netlink_unicast+0x289/0x3e0 > [89408.372533] netlink_sendmsg+0x215/0x440 > [89408.372551] __sys_sendto+0x234/0x240 > [89408.372571] __x64_sys_sendto+0x28/0x30 > [89408.372585] x64_sys_call+0x1909/0x1da0 > [89408.372604] do_syscall_64+0x7a/0xfa0 > [89408.373140] ? clear_bhb_loop+0x60/0xb0 > [89408.373647] entry_SYSCALL_64_after_hwframe+0x76/0x7e > [89408.378887] > > > Fixes: a251eee62133 ("idpf: add SRIOV support and other ndo_ops") > Signed-off-by: Sreedevi Joshi > Reviewed-by: Sridhar Samudrala > Reviewed-by: Emil Tantilov > Reviewed-by: Aleksandr Loktionov > Reviewed-by: Paul Menzel Reviewed-by: Simon Horman