linux-kernel - Re: [PATCH net-next,v2] net: mana: Add handler for hardware servicing events

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250512141546.GI3339421@horms.kernel.org>
Date: Mon, 12 May 2025 15:15:46 +0100
From: Simon Horman <horms@...nel.org>
To: Haiyang Zhang <haiyangz@...rosoft.com>
Cc: linux-hyperv@...r.kernel.org, netdev@...r.kernel.org,
	decui@...rosoft.com, stephen@...workplumber.org, kys@...rosoft.com,
	paulros@...rosoft.com, olaf@...fle.de, vkuznets@...hat.com,
	davem@...emloft.net, wei.liu@...nel.org, edumazet@...gle.com,
	kuba@...nel.org, pabeni@...hat.com, leon@...nel.org,
	longli@...rosoft.com, ssengar@...ux.microsoft.com,
	linux-rdma@...r.kernel.org, daniel@...earbox.net,
	john.fastabend@...il.com, bpf@...r.kernel.org, ast@...nel.org,
	hawk@...nel.org, tglx@...utronix.de,
	shradhagupta@...ux.microsoft.com, andrew+netdev@...n.ch,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH net-next,v2] net: mana: Add handler for hardware
 servicing events

On Fri, May 09, 2025 at 04:16:43PM -0700, Haiyang Zhang wrote:
> To collaborate with hardware servicing events, upon receiving the special
> EQE notification from the HW channel, remove the devices on this bus.
> Then, after a waiting period based on the device specs, rescan the parent
> bus to recover the devices.
> 
> Signed-off-by: Haiyang Zhang <haiyangz@...rosoft.com>
> ---
> v2: 
> Added dev_dbg for service type as suggested by Shradha Gupta.
> Added driver cap bit.
> 
> ---
>  .../net/ethernet/microsoft/mana/gdma_main.c   | 63 +++++++++++++++++++
>  include/net/mana/gdma.h                       | 11 +++-
>  2 files changed, 72 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/ethernet/microsoft/mana/gdma_main.c b/drivers/net/ethernet/microsoft/mana/gdma_main.c

...

> +static void mana_serv_func(struct work_struct *w)
> +{
> +	struct mana_serv_work *mns_wk = container_of(w, struct mana_serv_work, serv_work);
> +	struct pci_dev *pdev = mns_wk->pdev;
> +	struct pci_bus *bus, *parent;

Please avoid lines wider than 80 columns in Networking code.  In this case
I would suggest separating the declaration and initialisation of mns_wk and
pdev.  Something like this (completely untested!):

	struct mana_serv_work *mns_wk;
	struct pci_bus *bus, *parent;
	struct pci_dev *pdev;

	mns_wk = container_of(w, struct mana_serv_work, serv_work);
	pdev = mns_wk->pdev;


...

> @@ -400,6 +441,28 @@ static void mana_gd_process_eqe(struct gdma_queue *eq)
>  		eq->eq.callback(eq->eq.context, eq, &event);
>  		break;
>  
> +	case GDMA_EQE_HWC_FPGA_RECONFIG:
> +	case GDMA_EQE_HWC_SOCMANA_CRASH:
> +		dev_dbg(gc->dev, "Recv MANA service type:%d\n", type);
> +
> +		if (gc->in_service) {
> +			dev_info(gc->dev, "Already in service\n");
> +			break;
> +		}
> +
> +		mns_wk = kzalloc(sizeof(*mns_wk), GFP_ATOMIC);
> +		if (!mns_wk) {
> +			dev_err(gc->dev, "Fail to alloc mana_serv_work\n");

The memory allocator will log a message on error.
So please don't also do so here.

> +			break;
> +		}
> +
> +		dev_info(gc->dev, "Start MANA service type:%d\n", type);
> +		gc->in_service = true;
> +		mns_wk->pdev = to_pci_dev(gc->dev);
> +		INIT_WORK(&mns_wk->serv_work, mana_serv_func);
> +		schedule_work(&mns_wk->serv_work);
> +		break;
> +
>  	default:
>  		break;
>  	}

...

-- 
pw-bot: changes-requested