From: Oleg Nesterov <oleg@redhat.com>
Date: Sun, 29 Jul 2012 18:22:18 +0000 (+0200)
Subject: uprobes: Kill write_opcode()->lock_page(new_page)
X-Git-Tag: v3.6-rc1~32^2~11
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=089ba999dc881a7549d97c55ac9e0052d061867d;p=pandora-kernel.git

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>
---

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