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

[Phil Sutter <phil@nwl.cc>]

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.

Thanks, Phil