This patch set proposes an improved fix for the race condition that
originally was fixed in commit 2a4a8b1e5d9d ("MIPS: Remove race window
in page fault handling").
I have used the flush_icache_page API that is marked as deprecated in
Documentation/cachetlb.txt. There are strong reasons to keep this API
because it is not possible to implement an efficient and race-free
lazy flushing using the other APIs.
You can refer to a discussion about the same issue in arch/arm where
they chose to implement the solution in set_pte_at. In arch/mips we
could not do this because we lack information about the executability
of the mapping in set_pte_at() and thus we would have to flush all
pages to be safe.
http://lists.infradead.org/pipermail/linux-arm-kernel/2010-November/030915.html
Lars Persson (2):
Revert "MIPS: Remove race window in page fault handling"
MIPS: Fix race condition in lazy cache flushing.
arch/mips/include/asm/cacheflush.h | 35 ++++++++++++++++++++---------------
arch/mips/include/asm/pgtable.h | 10 ++++++----
arch/mips/mm/cache.c | 27 ++++++++-------------------
3 files changed, 34 insertions(+), 38 deletions(-)
--
1.7.10.4
