5b727a3b01
When changing a kernel page from RO->RW, it's OK to leave stale TLB entries around, since doing a global flush is expensive and they pose no security problem. They can, however, generate a spurious fault, which we should catch and simply return from (which will have the side-effect of reloading the TLB to the current PTE). This can occur when running under Xen, because it frequently changes kernel pages from RW->RO->RW to implement Xen's pagetable semantics. It could also occur when using CONFIG_DEBUG_PAGEALLOC, since it avoids doing a global TLB flush after changing page permissions. Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Cc: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> |
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.. | ||
discontig_32.c | ||
extable.c | ||
fault.c | ||
highmem_32.c | ||
hugetlbpage.c | ||
init_32.c | ||
init_64.c | ||
ioremap.c | ||
k8topology_64.c | ||
Makefile | ||
Makefile_32 | ||
Makefile_64 | ||
mmap.c | ||
numa_64.c | ||
pageattr-test.c | ||
pageattr.c | ||
pgtable_32.c | ||
srat_64.c |