kernel/lib, branch linux-2.6.37.y

swiotlb: fix wrong panic

2011-03-07T23:05:10Z

commit fba99fa38b023224680308a482e12a0eca87e4e1 upstream. swiotlb's map_page wrongly calls panic() when it can't find a buffer fit for device's dma mask. It should return an error instead. Devices with an odd dma mask (i.e. under 4G) like b44 network card hit this bug (the system crashes): http://marc.info/?l=linux-kernel&m=129648943830106&w=2 If swiotlb returns an error, b44 driver can use the own bouncing mechanism. Reported-by: Chuck Ebbert Signed-off-by: FUJITA Tomonori Tested-by: Arkadiusz Miskiewicz Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

kref: add kref_test_and_get

2011-02-17T23:14:17Z

commit e4a683c899cd5a49f8d684a054c95bd115a0c005 upstream. Add kref_test_and_get() function, which atomically add a reference only if refcount is not zero. This prevent to add a reference to an object that is already being removed. Signed-off-by: Jerome Marchand Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

dynamic debug: Fix build issue with older gcc

2011-02-17T23:14:15Z

commit 2d75af2f2a7a6103a6d539a492fe81deacabde44 upstream. On older gcc (3.3) dynamic debug fails to compile: include/net/inet_connection_sock.h: In function `inet_csk_reset_xmit_timer': include/net/inet_connection_sock.h:236: error: duplicate label declaration `do_printk' include/net/inet_connection_sock.h:219: error: this is a previous declaration include/net/inet_connection_sock.h:236: error: duplicate label declaration `out' include/net/inet_connection_sock.h:219: error: this is a previous declaration include/net/inet_connection_sock.h:236: error: duplicate label `do_printk' include/net/inet_connection_sock.h:236: error: duplicate label `out' Fix, by reverting the usage of JUMP_LABEL() in dynamic debug for now. Reported-by: Tetsuo Handa Tested-by: Tetsuo Handa Signed-off-by: Jason Baron Signed-off-by: Steven Rostedt Signed-off-by: Greg Kroah-Hartman

Revert "debug_locks: set oops_in_progress if we will log messages."

2010-11-29T23:18:28Z

This reverts commit e0fdace10e75dac67d906213b780ff1b1a4cc360. On-list discussion seems to suggest that the robustness fixes for printk make this unnecessary and DaveM has also agreed in person at Kernel Summit and on list. The main problem with this code is once we hit a lockdep splat we always keep oops_in_progress set, the console layer uses oops_in_progress with KMS to decide when it should be showing the oops and not showing X, so it causes problems around suspend/resume time when a userspace resume can cause a console switch away from X, only if oops_in_progress is set (which is what we want if an oops actually is in progress, but not because we had a lockdep splat 2 days prior). Cc: David S Miller Cc: Ingo Molnar Signed-off-by: Dave Airlie Signed-off-by: Linus Torvalds

radix-tree: fix RCU bug

2010-11-12T15:55:32Z

Salman Qazi describes the following radix-tree bug: In the following case, we get can get a deadlock: 0. The radix tree contains two items, one has the index 0. 1. The reader (in this case find_get_pages) takes the rcu_read_lock. 2. The reader acquires slot(s) for item(s) including the index 0 item. 3. The non-zero index item is deleted, and as a consequence the other item is moved to the root of the tree. The place where it used to be is queued for deletion after the readers finish. 3b. The zero item is deleted, removing it from the direct slot, it remains in the rcu-delayed indirect node. 4. The reader looks at the index 0 slot, and finds that the page has 0 ref count 5. The reader looks at it again, hoping that the item will either be freed or the ref count will increase. This never happens, as the slot it is looking at will never be updated. Also, this slot can never be reclaimed because the reader is holding rcu_read_lock and is in an infinite loop. The fix is to re-use the same "indirect" pointer case that requires a slot lookup retry into a general "retry the lookup" bit. Signed-off-by: Nick Piggin Reported-by: Salman Qazi Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx

2010-10-28T02:04:36Z

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx: (48 commits) DMAENGINE: move COH901318 to arch_initcall dma: imx-dma: fix signedness bug dma/timberdale: simplify conditional ste_dma40: remove channel_type ste_dma40: remove enum for endianess ste_dma40: remove TIM_FOR_LINK option ste_dma40: move mode_opt to separate config ste_dma40: move channel mode to a separate field ste_dma40: move priority to separate field ste_dma40: add variable to indicate valid dma_cfg async_tx: make async_tx channel switching opt-in move async raid6 test to lib/Kconfig.debug dmaengine: Add Freescale i.MX1/21/27 DMA driver intel_mid_dma: change the slave interface intel_mid_dma: fix the WARN_ONs intel_mid_dma: Add sg list support to DMA driver intel_mid_dma: Allow DMAC2 to share interrupt intel_mid_dma: Allow IRQ sharing intel_mid_dma: Add runtime PM support DMAENGINE: define a dummy filter function for ste_dma40 ...

docbook: add idr/ida to kernel-api docbook

2010-10-27T00:40:56Z

Add idr/ida to kernel-api docbook. Fix typos and kernel-doc notation. Signed-off-by: Randy Dunlap Acked-by: Tejun Heo Cc: Naohiro Aota Cc: Jiri Kosina Signed-off-by: Linus Torvalds

Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile

2010-10-27T00:25:38Z

* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile: arch/tile: convert a BUG_ON to BUILD_BUG_ON arch/tile: make ptrace() work properly for TILE-Gx COMPAT mode arch/tile: support new info op generated by compiler arch/tile: minor whitespace/naming changes for string support files arch/tile: enable single-step support for TILE-Gx arch/tile: parameterize system PLs to support KVM port arch/tile: add Tilera's header as an open-source header arch/tile: Bomb C99 comments to C89 comments in tile's arch/tile: prevent corrupt top frame from causing backtracer runaway arch/tile: various top-level Makefile cleanups arch/tile: change lower bound on syscall error return to -4095 arch/tile: properly export __mb_incoherent for modules arch/tile: provide a definition of MAP_STACK kmemleak: add TILE to the list of supported architectures. char: hvc: check for error case arch/tile: Add a warning if we try to allocate too much vmalloc memory. arch/tile: update some comments to clarify register usage. arch/tile: use better "punctuation" for VMSPLIT_3_5G and friends arch/tile: Use tile: replace some BUG_ON checks with BUILD_BUG_ON checks

div64_u64(): improve precision on 32bit platforms

2010-10-26T23:52:19Z

The current implementation of div64_u64 for 32bit systems returns an approximately correct result when the divisor exceeds 32bits. Since doing 64bit division using 32bit hardware is a long since solved problem we just use one of the existing proven methods. Additionally, add a div64_s64 function to correctly handle doing signed 64bit division. Addresses https://bugzilla.redhat.com/show_bug.cgi?id=616105 Signed-off-by: Brian Behlendorf Signed-off-by: Oleg Nesterov Cc: Ben Woodard Cc: Jeremy Fitzhardinge Cc: Mark Grondona Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib/parser: cleanup match_number()

2010-10-26T23:52:19Z

Use new variable 'len' to make code more readable. Signed-off-by: Namhyung Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds