tree 46d3165ee51b97907c5e259ef7e99a39ef5e3c4c
parent 18fc694578719686df59e31ae32dd862eb5f0ba8
author James Morse <james.morse@arm.com> 1472223822 +0100
committer Alex Shi <alex.shi@linaro.org> 1490325881 +0800

arm64: kernel: Fix unmasked debug exceptions when restoring mdscr_el1

Changes to make the resume from cpu_suspend() code behave more like
secondary boot caused debug exceptions to be unmasked early by
__cpu_setup(). We then go on to restore mdscr_el1 in cpu_do_resume(),
potentially taking break or watch points based on uninitialised registers.

Mask debug exceptions in cpu_do_resume(), which is specific to resume
from cpu_suspend(). Debug exceptions will be restored to their original
state by local_dbg_restore() in cpu_suspend(), which runs after
hw_breakpoint_restore() has re-initialised the other registers.

Reported-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Fixes: cabe1c81ea5b ("arm64: Change cpu_resume() to enable mmu early then access sleep_sp by va")
Cc: <stable@vger.kernel.org> # 4.7+
Signed-off-by: James Morse <james.morse@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 744c6c37cc18705d19e179622f927f5b781fe9cc)
Signed-off-by: Alex Shi <alex.shi@linaro.org>