1b23336ad9
Fix a problem in the IDR system, where an idr_remove_all() hands a data element to call_rcu() (via free_layer()) before making that data element inaccessible to new readers. This is very bad, and results in readers still having a reference to this data element at the end of the grace period. Tests on large machines that concurrently map and unmap user-space memory within the same multithreaded process result in crashes within about five minutes. Applying this patch increases the kernel's longevity to the three-to-eight-hour range. There appear to be other similar problems in idr_get_empty_slot() and sub_remove(), but I fixed the easy one in idr_remove_all() first. It is therefore no surprise that failures still occur. Located-by: Milton Miller II <miltonm@austin.ibm.com> Tested-by: Milton Miller II <miltonm@austin.ibm.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Manfred Spraul <manfred@colorfullife.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| .. | ||
| lzo | ||
| reed_solomon | ||
| zlib_deflate | ||
| zlib_inflate | ||
| .gitignore | ||
| Kconfig | ||
| Kconfig.debug | ||
| Kconfig.kgdb | ||
| Makefile | ||
| argv_split.c | ||
| audit.c | ||
| bcd.c | ||
| bitmap.c | ||
| bitrev.c | ||
| bug.c | ||
| bust_spinlocks.c | ||
| check_signature.c | ||
| cmdline.c | ||
| cpumask.c | ||
| crc-ccitt.c | ||
| crc-itu-t.c | ||
| crc-t10dif.c | ||
| crc7.c | ||
| crc16.c | ||
| crc32.c | ||
| crc32defs.h | ||
| ctype.c | ||
| debug_locks.c | ||
| debugobjects.c | ||
| dec_and_lock.c | ||
| devres.c | ||
| div64.c | ||
| dump_stack.c | ||
| dynamic_printk.c | ||
| extable.c | ||
| fault-inject.c | ||
| find_last_bit.c | ||
| find_next_bit.c | ||
| gen_crc32table.c | ||
| genalloc.c | ||
| halfmd4.c | ||
| hexdump.c | ||
| hweight.c | ||
| idr.c | ||
| inflate.c | ||
| int_sqrt.c | ||
| iomap.c | ||
| iomap_copy.c | ||
| iommu-helper.c | ||
| ioremap.c | ||
| irq_regs.c | ||
| is_single_threaded.c | ||
| kasprintf.c | ||
| kernel_lock.c | ||
| klist.c | ||
| kobject.c | ||
| kobject_uevent.c | ||
| kref.c | ||
| libcrc32c.c | ||
| list_debug.c | ||
| lmb.c | ||
| locking-selftest-hardirq.h | ||
| locking-selftest-mutex.h | ||
| locking-selftest-rlock-hardirq.h | ||
| locking-selftest-rlock-softirq.h | ||
| locking-selftest-rlock.h | ||
| locking-selftest-rsem.h | ||
| locking-selftest-softirq.h | ||
| locking-selftest-spin-hardirq.h | ||
| locking-selftest-spin-softirq.h | ||
| locking-selftest-spin.h | ||
| locking-selftest-wlock-hardirq.h | ||
| locking-selftest-wlock-softirq.h | ||
| locking-selftest-wlock.h | ||
| locking-selftest-wsem.h | ||
| locking-selftest.c | ||
| parser.c | ||
| percpu_counter.c | ||
| plist.c | ||
| prio_heap.c | ||
| prio_tree.c | ||
| proportions.c | ||
| radix-tree.c | ||
| random32.c | ||
| ratelimit.c | ||
| rbtree.c | ||
| reciprocal_div.c | ||
| rwsem-spinlock.c | ||
| rwsem.c | ||
| scatterlist.c | ||
| sha1.c | ||
| show_mem.c | ||
| smp_processor_id.c | ||
| sort.c | ||
| spinlock_debug.c | ||
| string.c | ||
| string_helpers.c | ||
| swiotlb.c | ||
| syscall.c | ||
| textsearch.c | ||
| ts_bm.c | ||
| ts_fsm.c | ||
| ts_kmp.c | ||
| vsprintf.c | ||