20273941f2
Christoph reported a nice splat which illustrated a race in the new stack based kmap_atomic implementation. The problem is that we pop our stack slot before we're completely done resetting its state -- in particular clearing the PTE (sometimes that's CONFIG_DEBUG_HIGHMEM). If an interrupt happens before we actually clear the PTE used for the last slot, that interrupt can reuse the slot in a dirty state, which triggers a BUG in kmap_atomic(). Fix this by introducing kmap_atomic_idx() which reports the current slot index without actually releasing it and use that to find the PTE and delay the _pop() until after we're completely done. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reported-by: Christoph Hellwig <hch@infradead.org> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| .. | ||
| Kconfig | ||
| Makefile | ||
| abort-ev4.S | ||
| abort-ev4t.S | ||
| abort-ev5t.S | ||
| abort-ev5tj.S | ||
| abort-ev6.S | ||
| abort-ev7.S | ||
| abort-lv4t.S | ||
| abort-macro.S | ||
| abort-nommu.S | ||
| alignment.c | ||
| cache-fa.S | ||
| cache-feroceon-l2.c | ||
| cache-l2x0.c | ||
| cache-tauros2.c | ||
| cache-v3.S | ||
| cache-v4.S | ||
| cache-v4wb.S | ||
| cache-v4wt.S | ||
| cache-v6.S | ||
| cache-v7.S | ||
| cache-xsc3l2.c | ||
| context.c | ||
| copypage-fa.c | ||
| copypage-feroceon.c | ||
| copypage-v3.c | ||
| copypage-v4mc.c | ||
| copypage-v4wb.c | ||
| copypage-v4wt.c | ||
| copypage-v6.c | ||
| copypage-xsc3.c | ||
| copypage-xscale.c | ||
| dma-mapping.c | ||
| extable.c | ||
| fault-armv.c | ||
| fault.c | ||
| fault.h | ||
| flush.c | ||
| highmem.c | ||
| init.c | ||
| iomap.c | ||
| ioremap.c | ||
| mm.h | ||
| mmap.c | ||
| mmu.c | ||
| nommu.c | ||
| pabort-legacy.S | ||
| pabort-v6.S | ||
| pabort-v7.S | ||
| pgd.c | ||
| proc-arm6_7.S | ||
| proc-arm7tdmi.S | ||
| proc-arm9tdmi.S | ||
| proc-arm720.S | ||
| proc-arm740.S | ||
| proc-arm920.S | ||
| proc-arm922.S | ||
| proc-arm925.S | ||
| proc-arm926.S | ||
| proc-arm940.S | ||
| proc-arm946.S | ||
| proc-arm1020.S | ||
| proc-arm1020e.S | ||
| proc-arm1022.S | ||
| proc-arm1026.S | ||
| proc-fa526.S | ||
| proc-feroceon.S | ||
| proc-macros.S | ||
| proc-mohawk.S | ||
| proc-sa110.S | ||
| proc-sa1100.S | ||
| proc-syms.c | ||
| proc-v6.S | ||
| proc-v7.S | ||
| proc-xsc3.S | ||
| proc-xscale.S | ||
| tlb-fa.S | ||
| tlb-v3.S | ||
| tlb-v4.S | ||
| tlb-v4wb.S | ||
| tlb-v4wbi.S | ||
| tlb-v6.S | ||
| tlb-v7.S | ||
| vmregion.c | ||
| vmregion.h | ||