uprobes: Kill write_opcode()->lock_page(new_page)

write_opcode() does lock_page(new_page) for no reason. Nobody
can see this page until __replace_page() exposes it under ptl
lock, and we do nothing with this page after pte_unmap_unlock().

If nothing else, the similar code in do_wp_page() doesn't lock
the new page for page_add_new_anon_rmap/set_pte_at_notify.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120729182218.GA20315@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Oleg Nesterov 2012-07-29 20:22:18 +02:00 committed by Ingo Molnar
parent c517ee744b
commit 089ba999dc
1 changed files with 0 additions and 2 deletions

View File

@ -239,9 +239,7 @@ retry:
if (ret)
goto unlock_out;
lock_page(new_page);
ret = __replace_page(vma, vaddr, old_page, new_page);
unlock_page(new_page);
unlock_out:
unlock_page(old_page);