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5.8.2-RC1 and mp2

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Stas Bekman
October 28, 2003 15:45
5.8.2-RC1 and mp2
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There is something that I don't understand. I thought you reverted the 
PERL_HASH behavior to how it was in 5.8.0. This is not the case. If I remove 
the workaround we had for 5.8.1, 5.8.2 breaks mp2.

To remind what the story is: as mp2 uses PERL_HASH to cache the key hashes, 
the hash seed has to stay indentical across different perl interpreters. The 
workaround for 5.8.1 was to take over the setting PL_hash_seed and telling 
Perl not to reset it by setting PL_hash_seed_set to TRUE>

I remember Nick saying, that 8.2 sets that hash seed to 0 and keeps it that 
way, taking special measures only if under attack. I haven't debugged the 
issue yet, but it seems that in 5.8.2 PERL_HASH is not a deterministic 
function and will return different values at different times. This is not how 
it was in 5.8.0. Before I fire up gdb, can you please summarize how different 
5.8.2 is from 5.8.0 in the hash seed aspect? Thanks.

This is all before the attack situation is triggered. I'll be able to tell 
whether it breaks anything only after getting to see the special test that 
triggers re-hashing.

Stas Bekman            JAm_pH ------> Just Another mod_perl Hacker     mod_perl Guide --->

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