On Tue, Oct 20, 2020 at 04:29:36PM +0200, Marek Vasut wrote:
> On 10/20/20 4:07 PM, Tom Rini wrote:
> > On Tue, Oct 20, 2020 at 11:05:40AM +0200, Marek Vasut wrote:
> >> On 10/20/20 2:27 AM, Reuben Dowle wrote:
> >>>>> What assumptions? Any code that assumes 4 byte alignment will also work
> >>>> on 8 byte alignment.
> >>>>>
> >>>>> Reverting is not the same as assuming ALIGN(...4) if incoming data is
> >>>>> not
> >>>> already aligned to 4 bytes (as was the case when I saw crashes).
> >>>>
> >>>> Can the incoming data _not_ be 4 byte aligned ?
> >>>> How can this be replicated ?
> >>>
> >>> In my case I have an offline signing process (separate from build server
> >>> to keep secure boot keys safe), and this runs a script which also patches
> >>> the main uboot device tree with some extra properties, then updates main
> >>> uboot dtb with kernel signature, then finally updates the spl dtb with
> >>> the uboot signature. I think when mkimage patches the dtb with the
> >>> signatures, this results in the alignment issues (the unsigned bootloader
> >>> direct from the uboot make process does not experience this issue).
> >>>
> >>> Possibly using mkimage to add padding would also fix the alignment issue
> >>> I see at boot time.
> >>>
> >>>>> Interesting. I had not noticed the -B parameter previously. I had
> >>>>> originally
> >>>> fixed this issue on an older version of uboot that did not have that
> >>>> option,
> >>>> and later rebased the fix to newer uboot. I would need to do some
> >>>> testing to
> >>>> see if this would fix it as well.
> >>>>
> >>>> I believe this is the way to handle this if you are building a custom DT
> >>>> for U-
> >>>> Boot -- just make sure it has the correct parameters. I think this is
> >>>> also related
> >>>> to:
> >>>> 20a154f95b ("mkimage: fit: Do not tail-pad fitImage with external data")
> >>>
> >>> I will look into this, although unfortunately I am very busy with other
> >>> projects right now so can't retest th
> >>
> >> In that case, I would propose to revert this to fix existing boards in
> >> mainline, and if your tests are not successful, revisit this issue.
> >>
> >> I am rather sure what you are hitting is related to the mkimage patch
> >> above, there was a lengthy discussion on that topic before.
> >
> > This gets back to what I was saying earlier in this thread. But to
> > expand on it, we have been, but cannot, use the same variable for both
> > "this is where we have the DTB at runtime to use" and "this is where the
> > DTB happens to exist when we get here". For the case of "we copy the
> > device tree to $address", $address must be 8 bytes aligned. For the
> > case of "we use an externally provided DTB in place" I don't like the
> > idea of, and worry a lot about, assuming it's going to be 8 byte
> > aligned. But I can set that aside for the moment. That said, in that
> > second case we need to set $address to where the device tree is.
>
> I don't think I understand this paragraph at all ?OK. Maybe I can better explain it after you walk through how changing the "copy the DTB to this address" to be 8 byte aligned is leading to failure, as I ask below. > > That all said, I'm still not quite sure how you're ending up in the > > place you're ending up. Which if/else paths in spl_fit_append_fdt() is > > your exact platform hitting, and where is what in memory? > > Is this a question for me or for Reuben ? For you, the person with the current failure. Please walk me through how / where that function is now failing. With address values (approximate if you can't get the exact ones). -- Tom
signature.asc
Description: PGP signature
