Re: [PATCH 02/10] arm: Update linker scripts to ensure appended device tree is aligned

[Tom Rini <trini@konsulko.com>]

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On Wed, Feb 04, 2026 at 10:16:12PM +0100, Phil Sutter wrote:
> Hi,
> 
> On Thu, Jan 15, 2026 at 04:19:32PM -0600, Tom Rini wrote:
> > With commit 0535e46d55d7 ("scripts/dtc: Update to upstream version
> > v1.7.2-35-g52f07dcca47c") it is now a fatal error to U-Boot if our
> > device tree is not 8-byte aligned. In commit f613a6e15ef7 ("ARM: OMAP2+:
> > Pad SPL binary to 8-byte alignment before DTB") Beleswar Padhi explains
> > that we must have ALIGN(x) statements inside of a section to ensure that
> > padding is included and not simply that the linker address counter is
> > incremented. To that end, this patch:
> > - Expands some linker sections to be more readable when adding a second
> >   statement to the section.
> > - Aligns the final section before _end (for U-Boot) or
> >   _image_binary_end or __bss_end (for xPL phases) by 8-bytes by adding
> >   '. = ALIGN(8);' to the final section before the symbol.
> > - Ensure that we do have alignment by adding an ASSERT so that when not
> >   aligned we fail to link (and explain why).
> > - Remove now-spurious  '. = ALIGN(x);' statements that were intended to
> >   provide the above alignments.
> > 
> > Signed-off-by: Tom Rini <trini@konsulko.com>
> 
> For unclear reasons, this seems to break boot via xmodem protocol on my
> Synology DS414. I found this commit via 'git bisect'. The symptom is:
> 
> | kwboot version 2026.04-rc1-00098-g6ad0cf8f83db
> | Detected kwbimage v1 with SPI boot signature
> | Patching image boot signature to UART
> | Aligning image header to Xmodem block size
> | Sending boot message. Please reboot the target...\
> | Sending boot image header (67584 bytes)...
> |   0 % [......................................................................]
> |  13 % [......................................................................]
> |  26 % [......................................................................]
> |  39 % [......................................................................]
> |  53 % [......................................................................]
> |  66 % [......................................................................]
> |  79 % [......................................................................]
> |  92 % [......................................                                ]
> | Done
> | Missing DTB
> | spl_init() failed: -2
> | ### ERROR ### Please RESET the board ###
> | 
> | 
> | xmodem: Connection timed out
> 
> Debug printf()s in fdtdec_prepare_fdt() show that fdt_check_header()
> returns -FDT_ERR_BADMAGIC.
> 
> With HEAD at a8d982e1f1726 ("x86: cpu: Fix crash on FTRACE enabled
> builds"), reverting arch/arm/cpu/u-boot-spl.lds like so:
> 
> | @@ -41,14 +41,21 @@ SECTIONS
> |                 __binman_sym_start = .;
> |                 KEEP(*(SORT(.binman_sym*)));
> |                 __binman_sym_end = .;
> | -               . = ALIGN(8);
> |         }
> |  
> | +       . = ALIGN(4); /* critical! */
> |         __image_copy_end = .;
> | +       .rel.dyn : {
> | +               __rel_dyn_start = .;
> | +               *(.rel*)
> | +               __rel_dyn_end = .;
> | +       }
> | +
> | +       . = ALIGN(8);
> |         _image_binary_end = .;
> |         _end = .;
> |  
> | -       .bss : {
> | +       .bss __rel_dyn_start (OVERLAY) : {
> |                 __bss_start = .;
> |                 *(.bss*)
> |                  . = ALIGN(8);
> 
> The SPL image starts up again and continues loading the real uboot
> image. Note that I have no idea what these changes actually do, so I
> need instructions if I should dig further.

Does:
https://patchwork.ozlabs.org/project/uboot/patch/20260130183635.2612933-1-trini@konsulko.com/
fix it?

-- 
Tom

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