gxp: introduce locked mapping search and remove

Bug: 289470723
Test: Passed the unittests; Can't reproduce the bug with Syzkaller
Signed-off-by: Junghoon Jang <junghoonjang@google.com>
Change-Id: I99d04201a27126e6a2a9a4e37b619601b9636a16
(cherry picked from commit b66c271952702040b61ceeb420d626e7c2651421)
3 files changed