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SubjectFix built-in early-load Intel microcode alignment
Intel Software Developer's Manual, volume 3, chapter 9.11.6 says:
"Note that the microcode update must be aligned on a 16-byte
boundary and the size of the microcode update must be 1-KByte
granular"

When early-load Intel microcode is loaded from initramfs,
userspace tool 'iucode_tool' has already 16-byte aligned those
microcode bits in that initramfs image. Image that was created
something like this:

iucode_tool --write-earlyfw=FOO.cpio microcode-files...

However, when early-load Intel microcode is loaded from built-in
firmware BLOB using CONFIG_EXTRA_FIRMWARE= kernel config option,
that 16-byte alignment is not guaranteed.

Fix this by forcing all built-in firmware BLOBs to 16-byte
alignment.


Signed-off-by: Jari Ruusu <jari.ruusu@gmail.com>

--- a/drivers/base/firmware_loader/builtin/Makefile
+++ b/drivers/base/firmware_loader/builtin/Makefile
@@ -17,7 +17,7 @@
filechk_fwbin = \
echo "/* Generated by $(src)/Makefile */" ;\
echo " .section .rodata" ;\
- echo " .p2align $(ASM_ALIGN)" ;\
+ echo " .p2align 4" ;\
echo "_fw_$(FWSTR)_bin:" ;\
echo " .incbin \"$(fwdir)/$(FWNAME)\"" ;\
echo "_fw_end:" ;\
--
Jari Ruusu 4096R/8132F189 12D6 4C3A DCDA 0AA4 27BD ACDF F073 3C80 8132 F189

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