From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Dooks Subject: Re: [PATCH] sh_eth: ensure pm_runtime cannot suspend the device during init Date: Mon, 17 Mar 2014 13:07:12 +0000 Message-ID: <5326F380.2000106@codethink.co.uk> References: <1395056275-5005-1-git-send-email-ben.dooks@codethink.co.uk> <5326F215.7010604@cogentembedded.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: linux-sh@vger.kernel.org, netdev@vger.kernel.org To: Sergei Shtylyov Return-path: In-Reply-To: <5326F215.7010604@cogentembedded.com> Sender: linux-sh-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On 17/03/14 13:01, Sergei Shtylyov wrote: > Hello. > > On 17-03-2014 15:37, Ben Dooks wrote: > >> The pm_rumtime work queue is causing the device to be suspended during >> initialisation, thus the initialisation may not be able to access >> registers >> properly. As the code is called from a work queue, it is possible that >> this >> is not seen from certain configurations/builds due to the asynchronos >> nature of the code. > >> Use pm_runtime_get_sync() and pm_runtime_put_sync() to ensure that the >> pm system does not suspend it during the probe() call and remove the >> now unnecessary pm_runtime_resume() call. > >> This fixes the external abort that can cause /sbin/init or other such >> init processed to die. > >> Signed-off-by: Ben Dooks >> Tested-by: Geert Uytterhoeven >> --- >> drivers/net/ethernet/renesas/sh_eth.c | 3 ++- >> 1 file changed, 2 insertions(+), 1 deletion(-) > >> diff --git a/drivers/net/ethernet/renesas/sh_eth.c >> b/drivers/net/ethernet/renesas/sh_eth.c >> index 4f76b5e..f1cfd64 100644 >> --- a/drivers/net/ethernet/renesas/sh_eth.c >> +++ b/drivers/net/ethernet/renesas/sh_eth.c > [...] >> @@ -2961,6 +2961,7 @@ static int sh_eth_drv_probe(struct >> platform_device *pdev) >> pr_info("Base address at 0x%x, %pM, IRQ %d.\n", >> (u32)ndev->base_addr, ndev->dev_addr, ndev->irq); >> >> + pm_runtime_put_sync(&pdev->dev); > > I think you forgot to also do that on error cleanup path. > >> platform_set_drvdata(pdev, ndev); >> >> return ret; > > WBR, Sergei Thanks, will check this. -- Ben Dooks http://www.codethink.co.uk/ Senior Engineer Codethink - Providing Genius