linux/lib
Florian Fainelli 2ce8e7ed00 dma-debug: prevent early callers from crashing
dma_debug_init() is called by architecture specific code at different
levels, but typically as a fs_initcall due to the debugfs initialization.
Some platforms may have early callers of the DMA-API, running prior to the
fs_initcall() level, which is not much of an issue unless
CONFIG_DMA_API_DEBUG is set.  When the DMA-API debugging facilities are
turned on a caller will go through:

debug_dma_map_{single,page}
  -> dma_mapping_error (inline function usually)
    -> debug_dma_mapping_error
      -> get_hash_bucket

Calling get_hash_bucket() returns a valid hash value since we hash on high
bits of the dma_addr cookie, but we will grab an unitialized spinlock,
which typically won't crash but produce a warning, the real crash will
however happen during the bucket list traversal because the list has not
been initialized yet.

An obvious solution is of course to move some of the offenders to run
after the fs_initcall level, but since this might not always be an option,
we add a flag "dma_debug_initialized" which is set to false by default,
and set to true once dma_debug_init() has had a chance to run.

The dma_debug_disabled() helper function previously introduced just needs
to check for dma_debug_initialized to allow the caller to proceed or not.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Horia Geanta <horia.geanta@freescale.com>
Cc: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-10 17:41:02 -08:00
..
fonts fonts: Add 6x10 font 2014-10-09 11:35:48 +03:00
lz4
lzo lzo: check for length overrun in variable length encoding. 2014-09-28 11:08:01 +02:00
mpi
raid6 lib/raid6: Add log level to printks 2014-10-14 13:08:29 +11:00
reed_solomon
xz
zlib_deflate
zlib_inflate
.gitignore
argv_split.c
asn1_decoder.c
assoc_array.c KEYS: Fix termination condition in assoc array garbage collection 2014-09-12 22:34:31 +10:00
atomic64_test.c
atomic64.c locking,arch: Rewrite generic atomic support 2014-08-14 12:48:14 +02:00
audit.c
average.c
bcd.c
bch.c
bitmap.c lib/bitmap.c: fix undefined shift in __bitmap_shift_{left|right}() 2014-10-29 16:33:14 -07:00
bitrev.c
bsearch.c
btree.c
bug.c
build_OID_registry
bust_spinlocks.c
check_signature.c
checksum.c
clz_ctz.c
clz_tab.c
cmdline.c lib: Add a generic cmdline parse function parse_option_str 2014-10-03 18:40:58 +01:00
compat_audit.c
cordic.c
cpu_rmap.c
cpu-notifier-error-inject.c
cpumask.c
crc-ccitt.c
crc-itu-t.c
crc-t10dif.c
crc7.c
crc8.c
crc16.c
crc32.c
crc32defs.h
ctype.c
debug_locks.c
debugobjects.c
dec_and_lock.c
decompress_bunzip2.c initramfs: support initramfs that is bigger than 2GiB 2014-08-08 15:57:26 -07:00
decompress_inflate.c initramfs: support initramfs that is bigger than 2GiB 2014-08-08 15:57:26 -07:00
decompress_unlz4.c initramfs: support initramfs that is bigger than 2GiB 2014-08-08 15:57:26 -07:00
decompress_unlzma.c initramfs: support initramfs that is bigger than 2GiB 2014-08-08 15:57:26 -07:00
decompress_unlzo.c initramfs: support initramfs that is bigger than 2GiB 2014-08-08 15:57:26 -07:00
decompress_unxz.c initramfs: support initramfs that is bigger than 2GiB 2014-08-08 15:57:26 -07:00
decompress.c initramfs: support initramfs that is bigger than 2GiB 2014-08-08 15:57:26 -07:00
devres.c
digsig.c
div64.c
dma-debug.c dma-debug: prevent early callers from crashing 2014-12-10 17:41:02 -08:00
dump_stack.c
dynamic_debug.c lib/dynamic_debug.c: use seq_open_private() instead of seq_open() 2014-10-14 02:18:14 +02:00
dynamic_queue_limits.c
earlycpio.c
extable.c
fault-inject.c
fdt_empty_tree.c
fdt_ro.c
fdt_rw.c
fdt_strerror.c
fdt_sw.c
fdt_wip.c
fdt.c
find_last_bit.c
find_next_bit.c
flex_array.c
flex_proportions.c proportions: add @gfp to init functions 2014-09-08 09:51:30 +09:00
gcd.c
gen_crc32table.c
genalloc.c lib/genalloc.c: export devm_gen_pool_create() for modules 2014-12-03 09:36:04 -08:00
glob.c
halfmd4.c
hash.c
hexdump.c Provide a binary to hex conversion function 2014-09-16 17:36:01 +01:00
hweight.c Make ARCH_HAS_FAST_MULTIPLIER a real config variable 2014-09-13 11:14:53 -07:00
idr.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2014-10-07 21:16:26 -04:00
inflate.c
int_sqrt.c
interval_tree_test.c
interval_tree.c
iomap_copy.c
iomap.c
iommu-helper.c
ioremap.c
iovec.c
irq_regs.c
is_single_threaded.c
jedec_ddr_data.c
kasprintf.c
Kconfig Make ARCH_HAS_FAST_MULTIPLIER a real config variable 2014-09-13 11:14:53 -07:00
Kconfig.debug Merge branches 'torture.2014.11.03a', 'cpu.2014.11.03a', 'doc.2014.11.13a', 'fixes.2014.11.13a', 'signal.2014.10.29a' and 'rt.2014.10.29a' into HEAD 2014-11-13 10:39:04 -08:00
Kconfig.kgdb
Kconfig.kmemcheck
kfifo.c kfifo: use BUG_ON 2014-08-08 15:57:25 -07:00
klist.c
kobject_uevent.c
kobject.c
kstrtox.c
kstrtox.h
lcm.c
libcrc32c.c crypto: LLVMLinux: Remove VLAIS usage from libcrc32c.c 2014-10-14 10:51:23 +02:00
list_debug.c
list_sort.c lib/list_sort.c: convert to pr_foo 2014-08-06 18:01:25 -07:00
llist.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 locking/lockdep: Revert qrwlock recusive stuff 2014-10-03 06:09:30 +02:00
lockref.c
lru_cache.c
Makefile reciprocal_div: objects with exported symbols should be obj-y rather than lib-y 2014-11-16 14:18:53 -05:00
md5.c
memory-notifier-error-inject.c
memweight.c
net_utils.c
nlattr.c
notifier-error-inject.c
notifier-error-inject.h
of-reconfig-notifier-error-inject.c
oid_registry.c
parser.c
pci_iomap.c
percpu_counter.c percpu_counter: add @gfp to percpu_counter_init() 2014-09-08 09:51:29 +09:00
percpu_ida.c
percpu_test.c
percpu-refcount.c percpu_ref: make INIT_ATOMIC and switch_to_atomic() sticky 2014-09-24 13:31:50 -04:00
plist.c
pm-notifier-error-inject.c
proportions.c proportions: add @gfp to init functions 2014-09-08 09:51:30 +09:00
radix-tree.c
random32.c random32: improvements to prandom_bytes 2014-08-24 18:36:01 -07:00
ratelimit.c
rational.c
rbtree_test.c
rbtree.c lib/rbtree.c: fix typo in comment of __rb_insert() 2014-08-08 15:57:24 -07:00
reciprocal_div.c
rhashtable.c lib: rhashtable - Remove weird non-ASCII characters from comments 2014-11-13 14:38:46 -05:00
scatterlist.c lib/scatterlist: fix memory leak with scsi-mq 2014-10-28 10:27:10 -06:00
sha1.c
show_mem.c mm: do not overwrite reserved pages counter at show_mem() 2014-12-02 17:32:07 -08:00
smp_processor_id.c
sort.c
stmp_device.c
string_helpers.c lib / string_helpers: introduce string_escape_mem() 2014-10-14 02:18:26 +02:00
string.c This adds a memzero_explicit() call which is guaranteed not to be 2014-10-24 12:33:32 -07:00
strncpy_from_user.c
strnlen_user.c
swiotlb.c
syscall.c
test_bpf.c net: bpf: fix compiler warnings in test_bpf 2014-09-22 16:21:30 -04:00
test_firmware.c
test_module.c
test_user_copy.c
test-kstrtox.c
test-string_helpers.c lib / string_helpers: introduce string_escape_mem() 2014-10-14 02:18:26 +02:00
textsearch.c lib/textsearch.c: remove textsearch_put reference from comments 2014-10-14 02:18:14 +02:00
timerqueue.c
ts_bm.c
ts_fsm.c
ts_kmp.c
ucs2_string.c
usercopy.c
uuid.c
vsprintf.c lib/vsprintf: add %*pE[achnops] format specifier 2014-10-14 02:18:26 +02:00