tree 8cea1d6d85b2141ecb3491bcf28115e80dc5e797
parent 928eb5f719dc885da35385595b314f43b9d1fb9a
parent 15bbb837dd57d148fdbb9a21c610943731d20429
author Tom Rini <trini@konsulko.com> 1731939846 -0600
committer Tom Rini <trini@konsulko.com> 1731939846 -0600

Merge patch series "Fix boot failure due to misaligned DMA buffer"

Nam Cao <namcao@linutronix.de> says:

We observed the following sporadic boot failure while booting from MMC
device:

=> boot
CACHE: Misaligned operation at range [9efa25f8, 9efa27f8]
CACHE: Misaligned operation at range [9efa25f8, 9efa27f8]
CACHE: Misaligned operation at range [9efa25f8, 9efa27f8]
CACHE: Misaligned operation at range [9efa25f8, 9efa27f8]
** Booting bootflow 'mmc@2194000.bootdev.part_1' with extlinux
Ignoring unknown command: �D���D��
Boot failed (err=-14)

The reason is because while allocating buffer to read a file from MMC,
alignment of 1 byte is used. Thus, the buffer doesn't work for performing
DMA, and garbage data is read.

While looking at this issue, I also noticed that if no alignment specified
(align=0) then fs_read_alloc() is documented to use the default. But the
default is no alignment. Therefore, other users of fs_read_alloc() which
specify align=0 may be broken as well.

The first patch changes extlinux_read_bootflow() to use proper buffer
alignment for DMA.

The second patch changes the default alignment of fs_read_alloc() to be
DMA-suitable, to fix other potential bugs.