The patch titled ACPI: avoid references to impossible processors. has been added to the -mm tree. Its filename is acpi-avoid-references-to-impossible-processors.patch *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find out what to do about this ------------------------------------------------------ Subject: ACPI: avoid references to impossible processors. From: Christoph Lameter <clameter@xxxxxxx> ACPI uses NR_CPUS in various loops and in some it accesses per cpu data of processors that are not present(!) and that will never be present. The pointers to per cpu data are typically not initialized for processors that are not present. So we seem to be reading something here from offset 0 in memory. Make ACPI use nr_cpu_ids instead. That stops at the end of the possible processors. Convert one loop to NR_CPUS to use the cpu_possible map instead. That way ranges of processor that can never be brought online are skipped during the loop. Signed-off-by: Christoph Lameter <clameter@xxxxxxx> Cc: Len Brown <lenb@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/acpi/processor_core.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff -puN drivers/acpi/processor_core.c~acpi-avoid-references-to-impossible-processors drivers/acpi/processor_core.c --- a/drivers/acpi/processor_core.c~acpi-avoid-references-to-impossible-processors +++ a/drivers/acpi/processor_core.c @@ -494,7 +494,7 @@ static int get_cpu_id(acpi_handle handle if (apic_id == -1) return apic_id; - for (i = 0; i < NR_CPUS; ++i) { + for_each_possible_cpu(i) { if (cpu_physical_id(i) == apic_id) return i; } @@ -632,7 +632,7 @@ static int __cpuinit acpi_processor_star return 0; } - BUG_ON((pr->id >= NR_CPUS) || (pr->id < 0)); + BUG_ON((pr->id >= nr_cpu_ids) || (pr->id < 0)); /* * Buggy BIOS check @@ -771,7 +771,7 @@ static int acpi_processor_remove(struct pr = acpi_driver_data(device); - if (pr->id >= NR_CPUS) { + if (pr->id >= nr_cpu_ids) { kfree(pr); return 0; } @@ -842,7 +842,7 @@ int acpi_processor_device_add(acpi_handl if (!pr) return -ENODEV; - if ((pr->id >= 0) && (pr->id < NR_CPUS)) { + if ((pr->id >= 0) && (pr->id < nr_cpu_ids)) { kobject_uevent(&(*device)->dev.kobj, KOBJ_ONLINE); } return 0; @@ -880,13 +880,13 @@ acpi_processor_hotplug_notify(acpi_handl break; } - if (pr->id >= 0 && (pr->id < NR_CPUS)) { + if (pr->id >= 0 && (pr->id < nr_cpu_ids)) { kobject_uevent(&device->dev.kobj, KOBJ_OFFLINE); break; } result = acpi_processor_start(device); - if ((!result) && ((pr->id >= 0) && (pr->id < NR_CPUS))) { + if ((!result) && ((pr->id >= 0) && (pr->id < nr_cpu_ids))) { kobject_uevent(&device->dev.kobj, KOBJ_ONLINE); } else { printk(KERN_ERR PREFIX "Device [%s] failed to start\n", @@ -909,7 +909,7 @@ acpi_processor_hotplug_notify(acpi_handl return; } - if ((pr->id < NR_CPUS) && (cpu_present(pr->id))) + if ((pr->id < nr_cpu_ids) && (cpu_present(pr->id))) kobject_uevent(&device->dev.kobj, KOBJ_OFFLINE); break; default: _ Patches currently in -mm which might be from clameter@xxxxxxx are acpi-avoid-references-to-impossible-processors.patch ia64-slim-down-__clear_bit_unlock.patch ia64-slim-down-__clear_bit_unlock-checkpatch-fixes.patch mem-policy-fix-mempolicy-usage-in-pci-driver.patch git-s390.patch do-not-use-stack-to-allocate-cpumask-for-cpumask_of_cpu.patch git-unionfs.patch git-x86.patch x86_64-make-sparsemem-vmemmap-the-default-memory-model-v2.patch pagecache-zeroing-zero_user_segment-zero_user_segments-and-zero_user.patch pagecache-zeroing-zero_user_segment-zero_user_segments-and-zero_user-fix.patch pagecache-zeroing-zero_user_segment-zero_user_segments-and-zero_user-fix-2.patch move-vmalloc_to_page-to-mm-vmalloc.patch vmalloc-add-const-to-void-parameters.patch i386-resolve-dependency-of-asm-i386-pgtableh-on-highmemh.patch i386-resolve-dependency-of-asm-i386-pgtableh-on-highmemh-checkpatch-fixes.patch is_vmalloc_addr-check-if-an-address-is-within-the-vmalloc-boundaries.patch vmalloc-clean-up-page-array-indexing.patch vunmap-return-page-array-passed-on-vmap.patch slub-move-count_partial.patch slub-rename-numa-defrag_ratio-to-remote_node_defrag_ratio.patch slub-consolidate-add_partial-and-add_partial_tail-to-one-function.patch slub-use-non-atomic-bit-unlock.patch slub-fix-coding-style-violations.patch slub-fix-coding-style-violations-checkpatch-fixes.patch slub-noinline-some-functions-to-avoid-them-being-folded-into-alloc-free.patch slub-move-kmem_cache_node-determination-into-add_full-and-add_partial.patch slub-move-kmem_cache_node-determination-into-add_full-and-add_partial-slub-workaround-for-lockdep-confusion.patch slub-avoid-checking-for-a-valid-object-before-zeroing-on-the-fast-path.patch slub-__slab_alloc-exit-path-consolidation.patch slub-provide-unique-end-marker-for-each-slab.patch slub-provide-unique-end-marker-for-each-slab-fix.patch slub-avoid-referencing-kmem_cache-structure-in-__slab_alloc.patch slub-optional-fast-path-using-cmpxchg_local.patch slub-do-our-own-locking-via-slab_lock-and-slab_unlock.patch slub-do-our-own-locking-via-slab_lock-and-slab_unlock-checkpatch-fixes.patch slub-do-our-own-locking-via-slab_lock-and-slab_unlock-fix.patch slub-restructure-slab-alloc.patch slub-comment-kmem_cache_cpu-structure.patch vm-allow-get_page_unless_zero-on-compound-pages.patch bufferhead-revert-constructor-removal.patch bufferhead-revert-constructor-removal-checkpatch-fixes.patch swapin_readahead-excise-numa-bogosity.patch page-allocator-clean-up-pcp-draining-functions.patch vmstat-small-revisions-to-refresh_cpu_vm_stats.patch page-allocator-get-rid-of-the-list-of-cold-pages.patch page-allocator-get-rid-of-the-list-of-cold-pages-fix.patch mm-sparsec-check-the-return-value-of-sparse_index_alloc.patch percpu-__percpu_alloc_mask-can-dynamically-size-percpu_data.patch revoke-core-code.patch slab-api-remove-useless-ctor-parameter-and-reorder-parameters-vs-revoke.patch memcontrol-move-oom-task-exclusion-to-tasklist.patch oom-add-sysctl-to-enable-task-memory-dump.patch add-cmpxchg_local-to-asm-generic-for-per-cpu-atomic-operations.patch add-cmpxchg_local-cmpxchg64-and-cmpxchg64_local-to-ia64.patch dentries-extract-common-code-to-remove-dentry-from-lru.patch dentries-extract-common-code-to-remove-dentry-from-lru-fix.patch reiser4.patch reiser4-portion-of-zero_user-cleanup-patch.patch page-owner-tracking-leak-detector.patch - To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html