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

From: Russell King - ARM Linux admin
Date: Tue Mar 05 2019 - 04:55:35 EST


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@xxxxxxxxxx wrote:
>
> > On Mon, Mar 4, 2019 at 3:48 PM Manivannan Sadhasivam
> > <manivannan.sadhasivam@xxxxxxxxxx> 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@xxxxxxxxxx> 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.

--
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