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Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Mikhail Ulyanov , Sergei Shtylyov , Thomas Petazzoni , =?UTF-8?Q?Niklas_S=C3=B6derlund?= , Claudiu Beznea , netdev@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org References: <20250122-fix_missing_rtnl_lock_phy_disconnect-v1-0-8cb9f6f88fd1@bootlin.com> <20250122-fix_missing_rtnl_lock_phy_disconnect-v1-1-8cb9f6f88fd1@bootlin.com> <806d2df6-68d3-4319-8ce6-7049563508cf@tuxon.dev> <20250123150814.6c46ec9a@kmaincent-XPS-13-7390> From: Claudiu Beznea Content-Language: en-US In-Reply-To: <20250123150814.6c46ec9a@kmaincent-XPS-13-7390> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 23.01.2025 16:08, Kory Maincent wrote: > On Thu, 23 Jan 2025 13:33:30 +0200 > Claudiu Beznea wrote: > >> Hi, Kory, >> >> On 22.01.2025 18:19, Kory Maincent wrote: >>> Fix the suspend path by ensuring the rtnl lock is held where required. >>> Calls to ravb_open, ravb_close and wol operations must be performed under >>> the rtnl lock to prevent conflicts with ongoing ndo operations. > >> >> I've test it. Looks good. >> >> Thank you for your patch. However, I think this could be simplified. The >> locking scheme looks complicated to me. E.g., this one works too: >> >> diff --git a/drivers/net/ethernet/renesas/ravb_main.c >> b/drivers/net/ethernet/renesas/ravb_main.c >> index bc395294a32d..cfe4f0f364f3 100644 >> --- a/drivers/net/ethernet/renesas/ravb_main.c >> +++ b/drivers/net/ethernet/renesas/ravb_main.c >> @@ -3217,10 +3217,16 @@ static int ravb_suspend(struct device *dev) >> >> netif_device_detach(ndev); >> >> - if (priv->wol_enabled) >> - return ravb_wol_setup(ndev); >> + if (priv->wol_enabled) { >> + rtnl_lock(); >> + ret = ravb_wol_setup(ndev); >> + rtnl_unlock(); >> + return ret; >> + } > > What happen if wol_enabled flag changes it state between the rtnl_lock and the > if condition? We will be in the wrong path. wol_enabled flag can't change in this suspend phase. The user space tasks are fronzen when ravb_suspend() is called. Thank you, Claudiu > > Regards,