[PATCH] Hold a read lock during the samba_dsdb stack init() phase

[jim]

Should these transactions be introduced after need_write is declared and 
only executed if a transaction is needed?
Shouldn't they be conditional on internal state so they can otherwise be 
skipped?

On 4/10/2018 9:10 PM, Andrew Bartlett via samba-technical wrote:
> --- a/python/samba/tests/dsdb_schema_attributes.py
> +++ b/python/samba/tests/dsdb_schema_attributes.py
> @@ -193,6 +193,14 @@ systemOnly: FALSE
>   
>           samdb2 = samba.tests.connect_samdb(self.lp.samdb_url())
>   
> +        # We now only update the @ATTRIBUTES when a transaction happens
> +        # rather than making a read of the DB do writes.
> +        #
> +        # This avoids locking issues and is more expected
> +
> +        samdb2.transaction_start()
> +        samdb2.transaction_commit()
> +
>           res = self.samdb.search(base="@ATTRIBUTES", scope=ldb.SCOPE_BASE,
>                                   attrs=["@TEST_EXTRA"])
>           self.assertEquals(len(res), 1)
> @@ -220,6 +228,14 @@ systemOnly: FALSE
>   
>           samdb2 = samba.tests.connect_samdb(self.lp.samdb_url())
>   
> +        # We now only update the @INDEXLIST when a transaction happens
> +        # rather than making a read of the DB do writes.
> +        #
> +        # This avoids locking issues and is more expected
> +
> +        samdb2.transaction_start()
> +        samdb2.transaction_commit()
> +
>           res = self.samdb.search(base="@INDEXLIST", scope=ldb.SCOPE_BASE,
>                                   attrs=["@TEST_EXTRA"])
>           self.assertEquals(len(res), 1)