Christoph Lameter fe76407da7 slub: Handle NULL parameter in kmem_cache_flags ... commit c6f58d9b36 upstream. Andreas Herrmann writes: When I've used slub_debug kernel option (e.g. "slub_debug=,skbuff_fclone_cache" or similar) on a debug session I've seen a panic like: Highbank #setenv bootargs console=ttyAMA0 root=/dev/sda2 kgdboc.kgdboc=ttyAMA0,115200 slub_debug=,kmalloc-4096 earlyprintk=ttyAMA0 ... Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = c0004000 [00000000] *pgd=00000000 Internal error: Oops: 5 [#1] SMP ARM Modules linked in: CPU: 0 PID: 0 Comm: swapper Tainted: G W 3.12.0-00048-gbe408cd #314 task: c0898360 ti: c088a000 task.ti: c088a000 PC is at strncmp+0x1c/0x84 LR is at kmem_cache_flags.isra.46.part.47+0x44/0x60 pc : [<c02c6da0>] lr : [<c0110a3c>] psr: 200001d3 sp : c088bea8 ip : c088beb8 fp : c088beb4 r10: 00000000 r9 : 413fc090 r8 : 00000001 r7 : 00000000 r6 : c2984a08 r5 : c0966e78 r4 : 00000000 r3 : 0000006b r2 : 0000000c r1 : 00000000 r0 : c2984a08 Flags: nzCv IRQs off FIQs off Mode SVC_32 ISA ARM Segment kernel Control: 10c5387d Table: 0000404a DAC: 00000015 Process swapper (pid: 0, stack limit = 0xc088a248) Stack: (0xc088bea8 to 0xc088c000) bea0: c088bed4 c088beb8 c0110a3c c02c6d90 c0966e78 00000040 bec0: ef001f00 00000040 c088bf14 c088bed8 c0112070 c0110a04 00000005 c010fac8 bee0: c088bf5c c088bef0 c010fac8 ef001f00 00000040 00000000 00000040 00000001 bf00: 413fc090 00000000 c088bf34 c088bf18 c0839190 c0112040 00000000 ef001f00 bf20: 00000000 00000000 c088bf54 c088bf38 c0839200 c083914c 00000006 c0961c4c bf40: c0961c28 00000000 c088bf7c c088bf58 c08392ac c08391c0 c08a2ed8 c0966e78 bf60: c086b874 c08a3f50 c0961c28 00000001 c088bfb4 c088bf80 c083b258 c0839248 bf80: 2f800000 0f000000 c08935b4 ffffffff c08cd400 ffffffff c08cd400 c0868408 bfa0: c29849c0 00000000 c088bff4 c088bfb8 c0824974 c083b1e4 ffffffff ffffffff bfc0: c08245c0 00000000 00000000 c0868408 00000000 10c5387d c0892bcc c0868404 bfe0: c0899440 0000406a 00000000 c088bff8 00008074 c0824824 00000000 00000000 [<c02c6da0>] (strncmp+0x1c/0x84) from [<c0110a3c>] (kmem_cache_flags.isra.46.part.47+0x44/0x60) [<c0110a3c>] (kmem_cache_flags.isra.46.part.47+0x44/0x60) from [<c0112070>] (__kmem_cache_create+0x3c/0x410) [<c0112070>] (__kmem_cache_create+0x3c/0x410) from [<c0839190>] (create_boot_cache+0x50/0x74) [<c0839190>] (create_boot_cache+0x50/0x74) from [<c0839200>] (create_kmalloc_cache+0x4c/0x88) [<c0839200>] (create_kmalloc_cache+0x4c/0x88) from [<c08392ac>] (create_kmalloc_caches+0x70/0x114) [<c08392ac>] (create_kmalloc_caches+0x70/0x114) from [<c083b258>] (kmem_cache_init+0x80/0xe0) [<c083b258>] (kmem_cache_init+0x80/0xe0) from [<c0824974>] (start_kernel+0x15c/0x318) [<c0824974>] (start_kernel+0x15c/0x318) from [<00008074>] (0x8074) Code: e3520000 01a00002 089da800 e5d03000 (e5d1c000) ---[ end trace 1b75b31a2719ed1d ]--- Kernel panic - not syncing: Fatal exception Problem is that slub_debug option is not parsed before create_boot_cache is called. Solve this by changing slub_debug to early_param. Kernels 3.11, 3.10 are also affected. I am not sure about older kernels. Christoph Lameter explains: kmem_cache_flags may be called with NULL parameter during early boot. Skip the test in that case. Reported-by: Andreas Herrmann <andreas.herrmann@calxeda.com> Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2013-11-29 11:11:52 -08:00
..
backing-dev.c
balloon_compaction.c
bootmem.c
bounce.c	mm/bounce.c: fix a regression where MS_SNAP_STABLE (stable pages snapshotting) was ignored	2013-10-13 16:08:33 -07:00
cleancache.c
compaction.c
debug-pagealloc.c
dmapool.c
fadvise.c
failslab.c
filemap_xip.c
filemap.c
fremap.c
frontswap.c	frontswap: fix incorrect zeroing and allocation size for frontswap_map	2013-06-12 16:29:46 -07:00
highmem.c
huge_memory.c	mm: Close races between THP migration and PMD numa clearing	2013-11-13 12:05:34 +09:00
hugetlb_cgroup.c
hugetlb.c	Fix TLB gather virtual address range invalidation corner cases	2013-08-20 08:43:05 -07:00
hwpoison-inject.c
init-mm.c
internal.h
interval_tree.c
Kconfig
Kconfig.debug
kmemcheck.c
kmemleak-test.c
kmemleak.c
ksm.c
maccess.c
madvise.c
Makefile
memblock.c
memcontrol.c	memcg: fix multiple large threshold notifications	2013-09-26 17:18:28 -07:00
memory_hotplug.c	mm/memory_hotplug.c: fix printk format warnings	2013-05-24 16:22:52 -07:00
memory-failure.c
memory.c	mm: numa: Sanitize task_numa_fault() callsites	2013-11-13 12:05:34 +09:00
mempolicy.c	mm: mempolicy: fix mbind_range() && vma_adjust() interaction	2013-08-04 16:51:14 +08:00
mempool.c
migrate.c	mm: Close races between THP migration and PMD numa clearing	2013-11-13 12:05:34 +09:00
mincore.c
mlock.c
mm_init.c
mmap.c	Fix TLB gather virtual address range invalidation corner cases	2013-08-20 08:43:05 -07:00
mmu_context.c
mmu_notifier.c
mmzone.c
mprotect.c	mm: Account for a THP NUMA hinting update as one PTE update	2013-11-13 12:05:34 +09:00
mremap.c
msync.c
nobootmem.c
nommu.c
oom_kill.c
page_alloc.c	mm/memory-hotplug: fix lowmem count overflow when offline pages	2013-07-21 18:21:36 -07:00
page_cgroup.c
page_io.c
page_isolation.c
page-writeback.c	writeback: fix negative bdi max pause	2013-11-04 04:31:06 -08:00
pagewalk.c	mm/pagewalk.c: fix walk_page_range() access of wrong PTEs	2013-11-13 12:05:34 +09:00
percpu-km.c
percpu-vm.c
percpu.c
pgtable-generic.c
process_vm_access.c
quicklist.c
readahead.c
rmap.c
shmem.c	cope with potentially long ->d_dname() output for shmem/hugetlb	2013-10-18 07:45:45 -07:00
slab_common.c	slab: prevent warnings when allocating with __GFP_NOWARN	2013-06-13 10:01:58 +03:00
slab.c	slab: fix init_lock_keys	2013-07-21 18:21:26 -07:00
slab.h	memcg: check that kmem_cache has memcg_params before accessing it	2013-09-07 22:09:58 -07:00
slob.c
slub.c	slub: Handle NULL parameter in kmem_cache_flags	2013-11-29 11:11:52 -08:00
sparse-vmemmap.c
sparse.c
swap_state.c	swap: avoid read_swap_cache_async() race to deadlock while waiting on discard I/O completion	2013-06-12 16:29:45 -07:00
swap.c	mm: fix aio performance regression for database caused by THP	2013-10-01 09:17:48 -07:00
swapfile.c	frontswap: fix incorrect zeroing and allocation size for frontswap_map	2013-06-12 16:29:46 -07:00
truncate.c
util.c
vmalloc.c	mm/vmalloc.c: fix an overflow bug in alloc_vmap_area()	2013-11-13 12:05:34 +09:00
vmpressure.c
vmscan.c	mm: avoid reinserting isolated balloon pages into LRU lists	2013-10-13 16:08:33 -07:00
vmstat.c