From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from stravinsky.debian.org (stravinsky.debian.org [82.195.75.108]) (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 8FA8C1F4174 for ; Thu, 4 Jun 2026 08:17:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=82.195.75.108 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780561042; cv=none; b=A37VKpNI0jLZHzm5MxFFTzoC3e6H51Rob7qGlJvEWTdei0Cpp+WioMqjmAPaUSN3KjMXPZgG5zmGziPHPd4d7tzvCUdV2iWtqlZgrlrGC+7DM20rs0qC+wx92fHJojYr93vfq7D5cRIbb5GBH1uXJqm3sYJ9jM2WKeTBGoayL00= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780561042; c=relaxed/simple; bh=MbBXDLLN2+8AL4Ih5EYGErcv9YBkh34L7MTEz/ptLxs=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=AUD5tmiNj53t9atODJWgN2bEM3NRKjy6zCW1a0U+/sUKiYNd/pWaqrPKxufng/hqZjb+OJg8/4cBD1Pkv/upi4EeYf5HUkF03PaVQyoAG0gj61AjCUCQXdPalJZmJSW47AyfrBy3Cpiv8YfVeJW0YmTvrU0wS5fZut13whCP5BY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=debian.org; spf=pass smtp.mailfrom=debian.org; dkim=pass (2048-bit key) header.d=debian.org header.i=@debian.org header.b=f15e3XuX; arc=none smtp.client-ip=82.195.75.108 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=debian.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=debian.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=debian.org header.i=@debian.org header.b="f15e3XuX" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=debian.org; s=smtpauto.stravinsky; h=X-Debian-User:In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=zyVYfWEZgqIx/CQc1BEe2jo/5M+qhbsyRuWc13UO/SE=; b=f15e3XuXyyggszA8ILLWruGBYF rZn2V/nhqLu1lpx0pHYD7NlPRK0etmLgcX53VCHPNbVs5ziJQWvKzOuaee8768+NZfsf0hC/B6ayG 9cUIfqfoY6B3BtM80bkaMHM3Y4X7shnifyWoeUIzUsZnm9nQFXTU+yl9mPay/bELpo4GVZmzV7lMB XC50MvomF2X/VqIRo/Y9P0cBDvhzQgGxsWKuWp7yoje6tg6fqP7XWS3cBNPxCcqdDTvph4rUqahQO DD+HxHG8OiSj5Gr6ocmDpUEmxQ8VSroq5HyVZLldxJXzXxlnpuMSHY8QDorF8c/+QgRd+wPQLdyJz JGwl+BQw==; Received: from authenticated-user by stravinsky.debian.org with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.96) (envelope-from ) id 1wV3GK-004Nel-02; Thu, 04 Jun 2026 08:17:12 +0000 Date: Thu, 4 Jun 2026 01:17:07 -0700 From: Breno Leitao To: Jakub Kicinski Cc: davem@davemloft.net, netdev@vger.kernel.org, edumazet@google.com, pabeni@redhat.com, andrew+netdev@lunn.ch, horms@kernel.org, michael.chan@broadcom.com, pavan.chebbi@broadcom.com, sdf@fomichev.me, aleksandr.loktionov@intel.com Subject: Re: [PATCH net] Reapply "bnxt_en: bring back rtnl_lock() in the bnxt_open() path" Message-ID: References: <20260603195845.2574426-1-kuba@kernel.org> 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: <20260603195845.2574426-1-kuba@kernel.org> X-Debian-User: leitao On Wed, Jun 03, 2026 at 12:58:45PM -0700, Jakub Kicinski wrote: > This reverts commit 850d9248d2eac662f869c766a598c877690c74e5. > This reapplies commit 325eb217e41f ("bnxt_en: bring back rtnl_lock() > in the bnxt_open() path"). > > Breno reports a lockdep warning in bnxt. During FW reset the driver > may end up calling netif_set_real_num_tx_queues() (if queue count > changes), so calls to bnxt_open() still require rtnl_lock. > > net/sched/sch_generic.c:1416 suspicious rcu_dereference_protected() usage! > > dev_qdisc_change_real_num_tx+0x54/0xe0 > netif_set_real_num_tx_queues+0x4ed/0xa80 > __bnxt_open_nic+0x9cb/0x3490 > bnxt_open+0x1cb/0x370 > bnxt_fw_reset_task+0x80d/0x1e80 > process_scheduled_works+0x9c1/0x13b0 > > The reverted commit was just an optimization / experiment > so let's go back to taking the lock. > > Reported-by: Breno Leitao > Link: https://lore.kernel.org/ah726OtFX-Qw3U-R@gmail.com > Fixes: 850d9248d2ea ("Revert "bnxt_en: bring back rtnl_lock() in the bnxt_open() path"") > Signed-off-by: Jakub Kicinski Reviewed-by: Breno Leitao