linux/arch/x86/mm
Yinghai Lu 2be19102b7 x86, NUMA: Fix empty memblk detection in numa_cleanup_meminfo()
numa_cleanup_meminfo() trims each memblk between low (0) and
high (max_pfn) limits and discards empty ones.  However, the
emptiness detection incorrectly used equality test.  If the
start of a memblk is higher than max_pfn, it is empty but fails
the equality test and doesn't get discarded.

The condition triggers when max_pfn is lower than start of a
NUMA node and results in memory misconfiguration - leading to
WARN_ON()s and other funnies.  The bug was discovered in devel
branch where 32bit too uses this code path for NUMA init.  If a
node is above the addressing limit, max_pfn ends up lower than
the node triggering this problem.

The failure hasn't been observed on x86-64 but is still possible
with broken hardware e820/NUMA info.  As the fix is very low
risk, it would be better to apply it even for 64bit.

Fix it by using >= instead of ==.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
[ Extracted the actual fix from the original patch and rewrote patch description. ]
Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/20110501171204.GO29280@htj.dyndns.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-05-01 19:15:11 +02:00
..
kmemcheck x86: Eliminate bp argument from the stack tracing routines 2010-11-18 14:37:34 +01:00
amdtopology_64.c x86-64, NUMA: Unify emulated distance mapping 2011-02-16 17:11:10 +01:00
dump_pagetables.c x86, mm: Create symbolic index into address_markers array 2010-07-20 16:56:19 -07:00
extable.c x86, 64-bit: Move K8 B step iret fixup to fault entry asm 2009-10-12 18:29:46 +02:00
fault.c x86/mm: Fix pgd_lock deadlock 2011-03-10 09:41:57 +01:00
gup.c thp: mmu_notifier_test_young 2011-01-13 17:32:46 -08:00
highmem_32.c mm: fix race in kunmap_atomic() 2010-10-27 18:03:05 -07:00
hugetlbpage.c x86: Fix common misspellings 2011-03-18 10:39:30 +01:00
init_32.c x86: Fix common misspellings 2011-03-18 10:39:30 +01:00
init_64.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2011-03-23 20:51:42 -07:00
init.c x86: Rename e820_table_* to pgt_buf_* 2011-02-24 14:52:18 +01:00
iomap_32.c mm: fix race in kunmap_atomic() 2010-10-27 18:03:05 -07:00
ioremap.c xen: Cope with unmapped pages when initializing kernel pagetable 2010-10-13 16:07:13 -07:00
kmmio.c x86, kmmio/mmiotrace: Fix double free of kmmio_fault_pages 2010-06-18 11:30:09 +02:00
Makefile x86-64, NUMA: Move NUMA emulation into numa_emulation.c 2011-02-22 11:10:08 +01:00
memblock.c x86, memblock: Remove __memblock_x86_find_in_range_size() 2010-10-05 21:45:43 -07:00
memtest.c x86, memblock: Replace e820_/_early string with memblock_ 2010-08-27 11:13:47 -07:00
mmap.c x86: Use helpers for rlimits 2010-01-27 15:17:31 -08:00
mmio-mod.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
numa_32.c x86, NUMA: Move *_numa_init() invocations into initmem_init() 2011-02-16 12:13:06 +01:00
numa_64.c x86, NUMA: Fix empty memblk detection in numa_cleanup_meminfo() 2011-05-01 19:15:11 +02:00
numa_emulation.c x86, numa: Fix cpu nodemasks for NUMA emulation and CONFIG_DEBUG_PER_CPU_MAPS 2011-04-21 11:31:00 +02:00
numa_internal.h x86-64, NUMA: Move NUMA emulation into numa_emulation.c 2011-02-22 11:10:08 +01:00
numa.c x86, numa: Fix cpu nodemasks for NUMA emulation and CONFIG_DEBUG_PER_CPU_MAPS 2011-04-21 11:31:00 +02:00
pageattr-test.c x86: make sure the CPA test code's use of _PAGE_UNUSED1 is obvious 2008-09-05 17:09:57 +02:00
pageattr.c x86: Fix common misspellings 2011-03-18 10:39:30 +01:00
pat_internal.h x86, pat: Fix memory leak in free_memtype 2010-05-26 11:26:04 -07:00
pat_rbtree.c rbtree: Undo augmented trees performance damage and regression 2010-07-05 14:43:50 +02:00
pat.c Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-08-06 10:17:52 -07:00
pf_in.c x86,mmiotrace: Add support for tracing STOS instruction 2010-08-02 01:32:01 +02:00
pf_in.h x86 mmiotrace: move files into arch/x86/mm/. 2008-05-24 11:25:37 +02:00
pgtable_32.c x86: remove last traces of quicklist usage 2010-05-24 13:33:31 -07:00
pgtable.c x86: Flush TLB if PGD entry is changed in i386 PAE mode 2011-03-18 11:44:01 +01:00
physaddr.c x86: split __phys_addr out into separate file 2009-09-10 11:48:55 -07:00
physaddr.h x86: split __phys_addr out into separate file 2009-09-10 11:48:55 -07:00
setup_nx.c x86, cpu: Only CPU features determine NX capabilities 2010-11-10 15:43:15 -08:00
srat_32.c x86-32, NUMA: Fix ACPI NUMA init broken by recent x86-64 change 2011-04-04 16:56:33 +02:00
srat_64.c x86-64, NUMA: Unify emulated distance mapping 2011-02-16 17:11:10 +01:00
testmmiotrace.c x86, kmmio/mmiotrace: Fix double free of kmmio_fault_pages 2010-06-18 11:30:09 +02:00
tlb.c x86, tlb, UV: Do small micro-optimization for native_flush_tlb_others() 2011-03-15 08:30:34 +01:00