Re: [PATCH 01/15] ARM: actions: fix a leaked reference by addingmissing of_node_put - Russell King

From: Russell King - ARM Linux admin <linux@armlinux.org.uk>
To: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Cc: "Heiko Stübner" <heiko@sntech.de>,
	"Maxime Ripard" <maxime.ripard@bootlin.com>,
	"Catalin Marinas" <catalin.marinas@arm.com>,
	"Linus Walleij" <linus.walleij@linaro.org>,
	"Liviu Dudau" <liviu.dudau@arm.com>,
	"Xu Wei" <xuwei5@hisilicon.com>,
	"Wen Yang" <wen.yang99@zte.com.cn>,
	"Tomer Maimon" <tmaimon77@gmail.com>,
	"Lorenzo Pieralisi" <lorenzo.pieralisi@arm.com>,
	"open list:ARM/Rockchip SoC..."
	<linux-rockchip@lists.infradead.org>,
	"Will Deacon" <will.deacon@arm.com>,
	"OpenBMC Maillist" <openbmc@lists.ozlabs.org>,
	"Magnus Damm" <magnus.damm@gmail.com>,
	"Michal Simek" <michal.simek@xilinx.com>,
	"Krzysztof Kozlowski" <krzk@kernel.org>,
	linux-samsung-soc <linux-samsung-soc@vger.kernel.org>,
	"Chen-Yu Tsai" <wens@csie.org>, "Kukjin Kim" <kgene@kernel.org>,
	bcm-kernel-feedback-list <bcm-kernel-feedback-list@broadcom.com>,
	"NXP Linux Team" <linux-imx@nxp.com>,
	"Brendan Higgins" <brendanhiggins@google.com>,
	wang.yi59@zte.com.cn, "Ray Jui" <rjui@broadcom.com>,
	"Sascha Hauer" <s.hauer@pengutronix.de>,
	"Florian Fainelli" <f.fainelli@gmail.com>,
	"Nancy Yuen" <yuenn@google.com>,
	"Linux ARM" <linux-arm-kernel@lists.infradead.org>,
	"Scott Branden" <sbranden@broadcom.com>,
	avifishman70@gmail.com, "Patrick Venture" <venture@google.com>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Linux-Renesas <linux-renesas-soc@vger.kernel.org>,
	"Dinh Nguyen" <dinguyen@kernel.org>,
	"Simon Horman" <horms@verge.net.au>,
	"Sascha Hauer" <kernel@pengutronix.de>,
	"Sudeep Holla" <sudeep.holla@arm.com>,
	"Fabio Estevam" <fabio.estevam@nxp.com>,
	"Shawn Guo" <shawnguo@kernel.org>,
	"Andreas Färber" <afaerber@suse.de>
Subject: Re: [PATCH 01/15] ARM: actions: fix a leaked reference by addingmissing of_node_put
Date: Tue, 5 Mar 2019 09:55:05 +0000	[thread overview]
Message-ID: <20190305095505.znposuv6avjtbfwf@shell.armlinux.org.uk> (raw)
In-Reply-To: <CAOZjjhnDYHkWCd-zDqkFpg5FPoj-UxxNwVxfbg6QEahiASm10w@mail.gmail.com>

On Tue, Mar 05, 2019 at 07:21:19AM +0530, Manivannan Sadhasivam wrote:
> On Tue, 5 Mar, 2019, 4:08 AM Linus Walleij <linus.walleij@linaro.org wrote:
> 
> > On Mon, Mar 4, 2019 at 3:48 PM Manivannan Sadhasivam
> > <manivannan.sadhasivam@linaro.org> wrote:
> > > On Mon, Mar 04, 2019 at 01:29:33PM +0100, Linus Walleij wrote:
> > > > On Fri, Mar 1, 2019 at 4:55 PM Manivannan Sadhasivam
> > > > <manivannan.sadhasivam@linaro.org> wrote:
> > > > > Hi Wen,
> > > > >
> > > > > On Fri, Mar 01, 2019 at 04:56:42PM +0800, Wen Yang wrote:
> > > > > > The call to of_get_next_child returns a node pointer with refcount
> > > > > > incremented thus it must be explicitly decremented after the last
> > > > > > usage.
> > > > > >
> > > > > > Detected by coccinelle with the following warnings:
> > > > > > ./arch/arm/mach-actions/platsmp.c:112:2-8: ERROR: missing
> > of_node_put; acquired a node pointer with refcount incremented on line 103,
> > but without a corresponding object release within this function.
> > > > > > ./arch/arm/mach-actions/platsmp.c:124:2-8: ERROR: missing
> > of_node_put; acquired a node pointer with refcount incremented on line 115,
> > but without a corresponding object release within this function.
> > > > > > ./arch/arm/mach-actions/platsmp.c:137:3-9: ERROR: missing
> > of_node_put; acquired a node pointer with refcount incremented on line 128,
> > but without a corresponding object release within this function.
> > > > > >
> > > > >
> > > > > We have a floating patch for this:
> > > > > https://www.spinics.net/lists/arm-kernel/msg694544.html
> > > > >
> > > > > Andreas: Can you please take a second look at the patchset submitted
> > by Linus
> > > > > Walleij and Russel for simplifying the Actions startup code?
> > > >
> > > > Andreas wrote a version of simplifying secondary startup in the
> > > > same spirit as Russell's patches, and it's merged and all
> > > > is fine I think.
> > > >
> > >
> > > Oops. I think I missed that! Can you please point me to that patch? And
> > how it
> > > got merged? I did the PR for actions stuff this time and haven't
> > included any
> > > mach-actions patches.
> >
> > I just did git log arch/arm/mach-actions but I think it came in quite some
> > time
> > ago, not last merge window:
> >
> > But you see:
> > commit 6c2eb3e76fb84e2eb46d484f71fab469c0d9532c
> > "ARM: owl: smp: Drop owl_secondary_boot()"
> > commit bad29933fef76fb6ee577f4a0b6d145c1f52f663
> > "ARM: owl: smp: Use __pa_symbol()"
> > commit 18cfd9429d8a82c49add8f3ca9d366599bfcac45
> > "ARM: owl: smp: Drop bogus holding pen"
> >
> > platsmp.c looks just fine these days. Except for what Wei's patch is
> > fixing,
> > of_node_put().
> >
> 
> Nope. platsmp.c still requires some cleanup like removing the redundant
> bootlock and pen_release flag as pointed out by Russel. Andreas just
> replied to your cleanup patches but there was no follow up since that. So,
> I guess we can just apply Russell's patches and this patch once Andreas is
> fine with it (it looks good to me though).

No.  My patches are in my tree queued for this merge window.  They
are part of a series that can not be broken up and merged separately
because all the per-platform patches need to be merged before the final
patch "ARM: smp: remove arch-provided "pen_release"" otherwise the
platforms break.  I thought that was already explained.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up
According to speedtest.net: 11.9Mbps down 500kbps up

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel