[U-Boot] [PATCH] env_mmc: fix buffer allocation for armv7

Wolfgang Denk wd at denx.de
Mon Oct 7 07:34:24 CEST 2013


Dear Tom,

In message <20131006204214.GO15917 at bill-the-cat> you wrote:
> 
> > Why do you hesitate to use the stack?
> 
> Mainly to allow us to work in restricted stack areas like SPL where we
> simply may not have that much space available.

But malloc() is drawing from the very same resource as the stack, even
more so: with a buffer on the stack, the memory isfreed completeky
upon return from the fucntion, with no reminders left.  With malloc()
you need to statically allocate the malloc pool size for the whole
runtime, and allocating the buffers may fragment tha area, so even
after freeing the buffers there is less space left for other purposes.

Especially in memory-tight situations you want to avoid malloc().

Best regards,

Wolfgang Denk

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