Most of the boot parameters actually come from the real-mode boot code
(arch/x86/boot). A few of them come from the bootloader.
With a version of Syslinux that recent there shouldn't be any issues,
especially since Syslinux is, for somewhat obvious reasons, my reference
bootloader. You may want to experiment with using the optional
linux.c32 module just to see if it changes the behaviour:
boot: linux.c32 kernel options...
Or, in the configuration file:
label blah
kernel linux.c32
append kernel options...
-hpa
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