s390/mm: fix off-by-one bug in 5-level page table handling
Martin Cermak reported that setting a uprobe doesn't work. Reason for this is that the common uprobes code tries to get an unmapped area at the last possible page within an address space. This broke with commit 1aea9b3f ("s390/mm: implement 5 level pages tables") which introduced an off-by-one bug which prevents to map anything at the last possible page within an address space. The check with the off-by-one bug however can be removed since with commit 8ab867cb ("s390/mm: fix BUG_ON in crst_table_upgrade") the necessary check is done at both call sites. Reported-by: Martin Cermak <mcermak@redhat.com> Bisected-by: Thomas Richter <tmricht@linux.vnet.ibm.com> Fixes: 1aea9b3f ("s390/mm: implement 5 level pages tables") Cc: <stable@vger.kernel.org> # v4.13+ Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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