[LinuxBIOS] patch: fix filo dependency on memory being zero

ron minnich rminnich at gmail.com
Thu Oct 4 16:44:28 CEST 2007

On 10/3/07, Stefan Reinauer <stepan at coresystems.de> wrote:

> > This patch makes qemu work again on v3. FILO was depending on bss being zero, which is not all that safe in embedded. It's better to zero things you are depending on being zero.
> > Signed-off-by: Ronald G. Minnich <rminnich at gmail.com>
> Let me guess.. is this with PAYLOAD_PREPARSE_ELF enabled?

not at all. It failed with either elf or not elf. The code in FILO
depends on BSS being zero'd. That's not a safe assumption. The fix
turned out to be very, very simple as you can see :-)

> What else is different in "embedded" when running LinuxBIOS?

The biggest is that you really can not assume anything about the state
of memory. In fact, it would be desirable to have linuxbios NOT zero
memory, in the event you are recovering from a failure and would like
a memory dump. In the pre-PC days, it was not unusual to scan memory
after reboot when a failure had occurred.


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