[ovs-discuss] net-next panic in ovs call to arch_fast_hash2 since e5a2c899
davem at davemloft.net
Fri Nov 14 02:45:49 UTC 2014
From: Jay Vosburgh <jay.vosburgh at canonical.com>
Date: Thu, 13 Nov 2014 18:15:32 -0800
> The "have feature" function, __intel_crc4_2_hash2, does not
> clobber %r8, and so the call does not panic on a system with
> X86_FEATURE_XMM4_2, although I'm not sure if that's a deliberate
> compiler action or just happenstance because __intel_crc4_2_hash2 uses
> fewer registers than __jhash2.
Perhaps alternative calls can only be used with assembler routines
that use specific calling conventions, and they therefore generally
don't work with C functions?
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