[U-Boot] [PATCH V2 3/7] lcd: prevent unaligned memory access when displaying splash screen

Wolfgang Denk wd at denx.de
Tue Jan 29 14:46:02 CET 2013


Dear Nikita Kiryanov,

In message <1359463349-11649-4-git-send-email-nikita at compulab.co.il> you wrote:
> When the bmp file is loaded to an address specified by the environment
> variable "splashimage", its header members might be unaligned.
> This happens because the bmp header starts with two byte-size fields followd by
> mostly 32 bit fields, so when the address in splashimage is not equal to aligned
> address plus/minus 2, the 32 bit members will be placed in unaligned addresses.
> This results in a data abort on targets that cannot handle unaligned memory
> accesses.

I don;t understand your +/- 2 argument.  When there are 32 bit fielkds
in the header, these have to be 32 bit aligned, right?

> Check that the address is safe to use, and fix it if it's not.

If you perform any such fixes (thus essentially not doing what the
user asked for), you should at least print a warning message so the
user gets aware of such issues.

Also, you should add the video custodian on Cc: for such patches.

[Done here].


Best regards,

Wolfgang Denk

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