Re: [PATCH] MIPS: vmlinux.lds.S: Fix appended dtb not properly aligned

From: Thomas Bogendoerfer
Date: Tue Mar 16 2021 - 18:05:51 EST


On Tue, Mar 16, 2021 at 03:45:15PM +0000, Paul Cercueil wrote:
> Commit 6654111c893f ("MIPS: vmlinux.lds.S: align raw appended dtb to 8
> bytes") changed the alignment from STRUCT_ALIGNMENT bytes to 8 bytes.
>
> The commit's message makes it sound like it was actually done on
> purpose, but this is not the case. The commit was written when raw
> appended dtb were not aligned at all. The STRUCT_ALIGN() was added a few
> days before, in commit 7a05293af39f ("MIPS: boot/compressed: Copy DTB to
> aligned address"). The true purpose of the commit was not to align
> specifically to 8 bytes, but to make sure that the generated vmlinux'
> size was properly padded to the alignment required for DTBs.
>
> While the switch to 8-byte alignment worked for vmlinux-appended dtb
> blobs, it broke vmlinuz-appended dtb blobs, as the decompress routine
> moves the blob to a STRUCT_ALIGNMENT aligned address.
>
> Fix this by changing the raw appended dtb blob alignment from 8 bytes
> back to STRUCT_ALIGNMENT bytes in vmlinux.lds.S.
>
> Fixes: 6654111c893f ("MIPS: vmlinux.lds.S: align raw appended dtb to 8 bytes")
> Cc: Bjørn Mork <bjorn@xxxxxxx>
> Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
> ---
> arch/mips/kernel/vmlinux.lds.S | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)

applied to mips-fixes.

Thomas.

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