From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Daney Subject: Re: [PATCH] net: thunderx: Fix broken of_node_put() code. Date: Fri, 8 Apr 2016 09:41:35 -0700 Message-ID: <5707DF3F.3000508@caviumnetworks.com> References: <1459472517-5696-1-git-send-email-ddaney.cavm@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Cc: "David S. Miller" , , , , Robert Richter , Sunil Goutham , David Daney To: David Daney Return-path: In-Reply-To: <1459472517-5696-1-git-send-email-ddaney.cavm@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Due to mail server malfunction, this patch was sent twice. Please ignore this duplicate. Thanks, David Daney On 03/31/2016 06:01 PM, David Daney wrote: > From: David Daney > > commit b7d3e3d3d21a ("net: thunderx: Don't leak phy device references > on -EPROBE_DEFER condition.") incorrectly moved the call to > of_node_put() outside of the loop. Under normal loop exit, the node > has already had of_node_put() called, so the extra call results in: > > [ 8.228020] ERROR: Bad of_node_put() on /soc@0/pci@848000000000/mrml-bridge0@1,0/bgx0/xlaui00 > [ 8.239433] CPU: 16 PID: 608 Comm: systemd-udevd Not tainted 4.6.0-rc1-numa+ #157 > [ 8.247380] Hardware name: www.cavium.com EBB8800/EBB8800, BIOS 0.3 Mar 2 2016 > [ 8.273541] Call trace: > [ 8.273550] [] dump_backtrace+0x0/0x210 > [ 8.273557] [] show_stack+0x24/0x2c > [ 8.273560] [] dump_stack+0x8c/0xb4 > [ 8.273566] [] of_node_release+0xa8/0xac > [ 8.273570] [] kobject_cleanup+0x8c/0x194 > [ 8.273573] [] kobject_put+0x44/0x6c > [ 8.273576] [] of_node_put+0x24/0x30 > [ 8.273587] [] bgx_probe+0x17c/0xcd8 [thunder_bgx] > [ 8.273591] [] pci_device_probe+0xa0/0x114 > [ 8.273596] [] driver_probe_device+0x178/0x418 > [ 8.273599] [] __driver_attach+0x100/0x118 > [ 8.273602] [] bus_for_each_dev+0x6c/0xac > [ 8.273605] [] driver_attach+0x30/0x38 > [ 8.273608] [] bus_add_driver+0x1f8/0x29c > [ 8.273611] [] driver_register+0x70/0x110 > [ 8.273617] [] __pci_register_driver+0x60/0x6c > [ 8.273623] [] bgx_init_module+0x40/0x48 [thunder_bgx] > [ 8.273626] [] do_one_initcall+0xcc/0x1c0 > [ 8.273631] [] do_init_module+0x68/0x1c8 > [ 8.273635] [] load_module+0xf44/0x11f4 > [ 8.273638] [] SyS_finit_module+0xb8/0xe0 > [ 8.273641] [] el0_svc_naked+0x24/0x28 > > Go back to the previous (correct) code that only did the extra > of_node_put() call on early exit from the loop. > > Signed-off-by: David Daney > --- > drivers/net/ethernet/cavium/thunder/thunder_bgx.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/drivers/net/ethernet/cavium/thunder/thunder_bgx.c b/drivers/net/ethernet/cavium/thunder/thunder_bgx.c > index 9679515..d20539a 100644 > --- a/drivers/net/ethernet/cavium/thunder/thunder_bgx.c > +++ b/drivers/net/ethernet/cavium/thunder/thunder_bgx.c > @@ -1011,10 +1011,11 @@ static int bgx_init_of_phy(struct bgx *bgx) > } > > lmac++; > - if (lmac == MAX_LMAC_PER_BGX) > + if (lmac == MAX_LMAC_PER_BGX) { > + of_node_put(node); > break; > + } > } > - of_node_put(node); > return 0; > > defer: >