pgsql: Detach shared memory from bgworkers without shmem access.

Detach shared memory from bgworkers without shmem access.

Since the postmaster won't perform a crash-and-restart sequence
for background workers which don't request shared memory access,
we'd better make sure that they can't corrupt shared memory.

Patch by me, review by Tom Lane.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/4d155d8b08fe08c1a1649fdbad61c6dcf4a8671f

Modified Files
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src/backend/postmaster/bgworker.c |   48 ++++++++++++++++++++++++++++++-------
1 file changed, 39 insertions(+), 9 deletions(-)