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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 | ||