[PATCH 02/14] lmb: Use CONFIG_LMB_*_REGIONS only if they are defined

Tom Rini trini at konsulko.com
Sat Sep 4 19:01:20 CEST 2021


[trimming the CC list]

On Sat, Sep 04, 2021 at 06:49:03PM +0200, Marek Vasut wrote:
> On 9/4/21 6:09 PM, Tom Rini wrote:
> > On Sat, Sep 04, 2021 at 06:05:50PM +0200, Marek Vasut wrote:
> > > On 9/4/21 5:17 PM, Tom Rini wrote:
> > > > On Sat, Sep 04, 2021 at 05:15:45PM +0200, Marek Vasut wrote:
> > > > > On 9/4/21 4:10 PM, Tom Rini wrote:
> > > > > [...]
> > > > > 
> > > > > > > > > > At this point, I think you should rework things to stop making
> > > > > > > > > > CONFIG_LMB be optional, it should be a def_bool y.
> > > > > > > > > 
> > > > > > > > > I disagree, see above.
> > > > > > > > 
> > > > > > > > The only reason "tools-only_defconfig" builds a useless u-boot binary
> > > > > > > > today is in CI where it would be more work than it's worth to make CI
> > > > > > > > exclude that from the build list.  But if you want to just do that
> > > > > > > > instead, I'll also accept adding -x tools-only to the azure/gitlab jobs
> > > > > > > > that build all other architectures, as tools-only is tested in its own
> > > > > > > > build job, for it's only valid build target.
> > > > > > > 
> > > > > > > The tools-only build is also used elsewhere, to build just that, tools.
> > > > > > 
> > > > > > I've repeatedly explained myself and what I'm looking for in v2 of this
> > > > > > series.  I will summarize one last time.  The "tools-only_defconfig" is
> > > > > > for tools, only.  Building anything other than the "tools-only" target
> > > > > > isn't useful.  In U-Boot itself, LMB is required as that is how we
> > > > > > prevent a number of CVEs from being trivial to exploit.  v2 of this
> > > > > > series needs to drop patches 1 and 2 of v1 of this series.  It can
> > > > > > further do any of:
> > > > > > 1. Nothing else.
> > > > > > 2. Add tools-only to the exclude list in the "build everything else" CI
> > > > > >       job.
> > > > > > 3. Make CONFIG_LMB be def_bool y.
> > > > > 
> > > > > If tools-only is for tools, only, then why should it enable LMB ?
> > > > > The tools are userspace tools, they do not need LMB, and so LMB can be
> > > > > disabled.
> > > > > 
> > > > > This is the part which is unclear to me.
> > > > 
> > > > I don't know why it's unclear to you at this point, sorry.
> > > 
> > > Well why exactly does a userspace program require LMB enabled ?
> > > What does LMB protect in there ? obviously not U-Boot.
> > 
> > I feel like you've lost the thread.
> 
> Can you please answer my questions above ?

I have.

-- 
Tom
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