Aqui é onde parou:
mremap(0xb7504000, 3075489792, 745472, MREMAP_MAYMOVE) = -1 EINVAL (Invalid argument)
Vamos ver como o mremap funciona:
mremap(old_address, old_size, new_size, int flags);
E a descrição do erro EINVAL:
EINVAL An invalid argument was given. Possible causes are:
old_address was not page aligned; a value other than
MREMAP_MAYMOVE or MREMAP_FIXED was specified in flags;
new_size was zero; new_size or new_address was invalid; or the
new address range specified by new_address and new_size
overlapped the old address range specified by old_address and
old_size; or MREMAP_FIXED was specified without also
specifying MREMAP_MAYMOVE.
Parece um bug SW. A solução alternativa é usar o SO de 64 bits para expandir o endereçamento da memória virtual.
Qual versão do clamav você usa?