Currently ioc->nr_tasks is used to decide two things - whether an ioc
is done issuing IOs and whether it's shared by multiple tasks. This
patch separate out the first into ioc->active_ref, which is acquired
and released using {get|put}_io_context_active() respectively.
This will be used to associate bio's with a given task. This patch
doesn't introduce any visible behavior change.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
ioc_task_link() is used to share %current's ioc on clone. If
%current->io_context is set, %current is guaranteed to have refcount
on the ioc and, thus, ioc_task_link() can't fail.
Replace error checking in ioc_task_link() with WARN_ON_ONCE() and make
it just increment refcount and nr_tasks.
-v2: Description typo fix (Vivek).
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Now that blkg additions / removals are always done under both q and
blkcg locks, the only places RCU locking is necessary are
blkg_lookup[_create]() for lookup w/o blkcg lock. This patch drops
unncessary RCU locking replacing it with plain blkcg locking as
necessary.
* blkiocg_pre_destroy() already perform proper locking and don't need
RCU. Dropped.
* blkio_read_blkg_stats() now uses blkcg->lock instead of RCU read
lock. This isn't a hot path.
* Now unnecessary synchronize_rcu() from queue exit paths removed.
This makes q->nr_blkgs unnecessary. Dropped.
* RCU annotation on blkg->q removed.
-v2: Vivek pointed out that blkg_lookup_create() still needs to be
called under rcu_read_lock(). Updated.
-v3: After the update, stats_lock locking in blkio_read_blkg_stats()
shouldn't be using _irq variant as it otherwise ends up enabling
irq while blkcg->lock is locked. Fixed.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
With the previous patch to move blkg list heads and counters to
request_queue and blkg, logic to manage them in both policies are
almost identical and can be moved to blkcg core.
This patch moves blkg link logic into blkg_lookup_create(), implements
common blkg unlink code in blkg_destroy(), and updates
blkg_destory_all() so that it's policy specific and can skip root
group. The updated blkg_destroy_all() is now used to both clear queue
for bypassing and elv switching, and release all blkgs on q exit.
This patch introduces a race window where policy [de]registration may
race against queue blkg clearing. This can only be a problem on cfq
unload and shouldn't be a real problem in practice (and we have many
other places where this race already exists). Future patches will
remove these unlikely races.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently, specific policy implementations are responsible for
maintaining list and number of blkgs. This duplicates code
unnecessarily, and hinders factoring common code and providing blkcg
API with better defined semantics.
After this patch, request_queue hosts list heads and counters and blkg
has list nodes for both policies. This patch only relocates the
necessary fields and the next patch will actually move management code
into blkcg core.
Note that request_queue->blkg_list[] and ->nr_blkgs[] are hardcoded to
have 2 elements. This is to avoid include dependency and will be
removed by the next patch.
This patch doesn't introduce any behavior change.
-v2: Now unnecessary conditional on CONFIG_BLK_CGROUP_MODULE removed
as pointed out by Vivek.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Keep track of all request_queues which have blkcg initialized and turn
on bypass and invoke blkcg_clear_queue() on all before making changes
to blkcg policies.
This is to prepare for moving blkg management into blkcg core. Note
that this uses more brute force than necessary. Finer grained shoot
down will be implemented later and given that policy [un]registration
almost never happens on running systems (blk-throtl can't be built as
a module and cfq usually is the builtin default iosched), this
shouldn't be a problem for the time being.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Rename and extend elv_queisce_start/end() to
blk_queue_bypass_start/end() which are exported and supports nesting
via @q->bypass_depth. Also add blk_queue_bypass() to test bypass
state.
This will be further extended and used for blkio_group management.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
elevator_ops->elevator_init_fn() has a weird return value. It returns
a void * which the caller should assign to q->elevator->elevator_data
and %NULL return denotes init failure.
Update such that it returns integer 0/-errno and sets elevator_data
directly as necessary.
This makes the interface more conventional and eases further cleanup.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This patch (as1519) fixes a bug in the block layer's disk-events
polling. The polling is done by a work routine queued on the
system_nrt_wq workqueue. Since that workqueue isn't freezable, the
polling continues even in the middle of a system sleep transition.
Obviously, polling a suspended drive for media changes and such isn't
a good thing to do; in the case of USB mass-storage devices it can
lead to real problems requiring device resets and even re-enumeration.
The patch fixes things by creating a new system-wide, non-reentrant,
freezable workqueue and using it for disk-events polling.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: <stable@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Since 2.6.39 (1196f8b), when a driver returns -ENOMEDIUM for open(),
__blkdev_get() calls rescan_partitions() to remove
in-kernel partition structures and raise KOBJ_CHANGE uevent.
However it ends up calling driver's revalidate_disk without open
and could cause oops.
In the case of SCSI:
process A process B
----------------------------------------------
sys_open
__blkdev_get
sd_open
returns -ENOMEDIUM
scsi_remove_device
<scsi_device torn down>
rescan_partitions
sd_revalidate_disk
<oops>
Oopses are reported here:
http://marc.info/?l=linux-scsi&m=132388619710052
This patch separates the partition invalidation from rescan_partitions()
and use it for -ENOMEDIUM case.
Reported-by: Huajun Li <huajun.li.lee@gmail.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
While updating locking, b2efa05265 "block, cfq: unlink
cfq_io_context's immediately" moved elevator_exit_icq_fn() invocation
from exit_io_context() to the final ioc put. While this doesn't cause
catastrophic failure, it effectively removes task exit notification to
elevator and cause noticeable IO performance degradation with CFQ.
On task exit, CFQ used to immediately expire the slice if it was being
used by the exiting task as no more IO would be issued by the task;
however, after b2efa05265, the notification is lost and disk could sit
idle needlessly, leading to noticeable IO performance degradation for
certain workloads.
This patch renames ioc_exit_icq() to ioc_destroy_icq(), separates
elevator_exit_icq_fn() invocation into ioc_exit_icq() and invokes it
from exit_io_context(). ICQ_EXITED flag is added to avoid invoking
the callback more than once for the same icq.
Walking icq_list from ioc side and invoking elevator callback requires
reverse double locking. This may be better implemented using RCU;
unfortunately, using RCU isn't trivial. e.g. RCU protection would
need to cover request_queue and queue_lock switch on cleanup makes
grabbing queue_lock from RCU unsafe. Reverse double locking should
do, at least for now.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-and-bisected-by: Shaohua Li <shli@kernel.org>
LKML-Reference: <CANejiEVzs=pUhQSTvUppkDcc2TNZyfohBRLygW5zFmXyk5A-xQ@mail.gmail.com>
Tested-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
icq->changed was used for ICQ_*_CHANGED bits. Rename it to flags and
access it under ioc->lock instead of using atomic bitops.
ioc_get_changed() is added so that the changed part can be fetched and
cleared as before.
icq->flags will be used to carry other flags.
Signed-off-by: Tejun Heo <tj@kernel.org>
Tested-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Modified the mmc_poweroff to resume before sending the poweroff
notification command. In sleep mode only AWAKE and RESET commands are
allowed, so before sending the poweroff notification command resume from
sleep mode and then send the notification command.
PowerOff Notify is tested on a Synopsis Designware Host Controller
(eMMC 4.5). The suspend to RAM and resume works fine.
Signed-off-by: Girish K S <girish.shivananjappa@linaro.org>
Tested-by: Girish K S <girish.shivananjappa@linaro.org>
Reviewed-by: Saugata Das <saugata.das@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
There is an understood mismatch between the voltage the host controller is
set to and the voltage supplied to the card by a fixed voltage regulator.
Teaching the driver to accept the mismatch is overly complicated. Instead
just accept the regulator's voltage.
This patch adds MMC_CAP2_BROKEN_VOLTAGE.
If the voltage didn't satisfy between min_uV and max_uV, try to change
the voltage in core.c. When changing the voltage, maybe use
regulator_set_voltage().
In regulator_set_voltage(), check the below condition.
/* sanity check */
if (!rdev->desc->ops->set_voltage &&
!rdev->desc->ops->set_voltage_sel) {
ret = -EINVAL;
goto out;
}
If some board should use the fixed-regulator, always return -EINVAL.
Then, eMMC didn't initialize always.
So if use a fixed-regulator, we need to add the MMC_CAP2_BROKEN_VOLTAGE.
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Ensure clocks are always enabled before any interaction with the
host controller driver. This makes sure that there is no race
between host execution and the core layer turning off clocks
in different context with clock gating framework.
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Per Forlin <per.forlin@stericsson.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Says Jens:
"Time to push off some of the pending items. I really wanted to wait
until we had the regression nailed, but alas it's not quite there yet.
But I'm very confident that it's "just" a missing expire on exit, so
fix from Tejun should be fairly trivial. I'm headed out for a week on
the slopes.
- Killing the barrier part of mtip32xx. It doesn't really support
barriers, and it doesn't need them (writes are fully ordered).
- A few fixes from Dan Carpenter, preventing overflows of integer
multiplication.
- A fixup for loop, fixing a previous commit that didn't quite solve
the partial read problem from Dave Young.
- A bio integer overflow fix from Kent Overstreet.
- Improvement/fix of the door "keep locked" part of the cdrom shared
code from Paolo Benzini.
- A few cfq fixes from Shaohua Li.
- A fix for bsg sysfs warning when removing a file it did not create
from Stanislaw Gruszka.
- Two fixes for floppy from Vivek, preventing a crash.
- A few block core fixes from Tejun. One killing the over-optimized
ioc exit path, cleaning that up nicely. Two others fixing an oops
on elevator switch, due to calling into the scheduler merge check
code without holding the queue lock."
* 'for-linus' of git://git.kernel.dk/linux-block:
block: fix lockdep warning on io_context release put_io_context()
relay: prevent integer overflow in relay_open()
loop: zero fill bio instead of return -EIO for partial read
bio: don't overflow in bio_get_nr_vecs()
floppy: Fix a crash during rmmod
floppy: Cleanup disk->queue before caling put_disk() if add_disk() was never called
cdrom: move shared static to cdrom_device_info
bsg: fix sysfs link remove warning
block: don't call elevator callbacks for plug merges
block: separate out blk_rq_merge_ok() and blk_try_merge() from elevator functions
mtip32xx: removed the irrelevant argument of mtip_hw_submit_io() and the unused member of struct driver_data
block: strip out locking optimization in put_io_context()
cdrom: use copy_to_user() without the underscores
block: fix ioc locking warning
block: fix NULL icq_cache reference
block,cfq: change code order
Quoth David:
1) GRO MAC header comparisons were ethernet specific, breaking other
link types. This required a multi-faceted fix to cure the originally
noted case (Infiniband), because IPoIB was lying about it's actual
hard header length. Thanks to Eric Dumazet, Roland Dreier, and
others.
2) Fix build failure when INET_UDP_DIAG is built in and ipv6 is modular.
From Anisse Astier.
3) Off by ones and other bug fixes in netprio_cgroup from Neil Horman.
4) ipv4 TCP reset generation needs to respect any network interface
binding from the socket, otherwise route lookups might give a
different result than all the other segments received. From Shawn
Lu.
5) Fix unintended regression in ipv4 proxy ARP responses, from Thomas
Graf.
6) Fix SKB under-allocation bug in sh_eth, from Yoshihiro Shimoda.
7) Revert skge PCI mapping changes that are causing crashes for some
folks, from Stephen Hemminger.
8) IPV4 route lookups fill in the wildcarded fields of the given flow
lookup key passed in, which is fine most of the time as this is
exactly what the caller's want. However there are a few cases that
want to retain the original flow key values afterwards, so handle
those cases properly. Fix from Julian Anastasov.
9) IGB/IXGBE VF lookup bug fixes from Greg Rose.
10) Properly null terminate filename passed to ethtool flash device
method, from Ben Hutchings.
11) S3 resume fix in via-velocity from David Lv.
12) Fix double SKB free during xmit failure in CAIF, from Dmitry
Tarnyagin.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (72 commits)
net: Don't proxy arp respond if iif == rt->dst.dev if private VLAN is disabled
ipv4: Fix wrong order of ip_rt_get_source() and update iph->daddr.
netprio_cgroup: fix wrong memory access when NETPRIO_CGROUP=m
netprio_cgroup: don't allocate prio table when a device is registered
netprio_cgroup: fix an off-by-one bug
bna: fix error handling of bnad_get_flash_partition_by_offset()
isdn: type bug in isdn_net_header()
net: Make qdisc_skb_cb upper size bound explicit.
ixgbe: ethtool: stats user buffer overrun
ixgbe: dcb: up2tc mapping lost on disable/enable CEE DCB state
ixgbe: do not update real num queues when netdev is going away
ixgbe: Fix broken dependency on MAX_SKB_FRAGS being related to page size
ixgbe: Fix case of Tx Hang in PF with 32 VFs
ixgbe: fix vf lookup
igb: fix vf lookup
e1000: add dropped DMA receive enable back in for WoL
gro: more generic L2 header check
IPoIB: Stop lying about hard_header_len and use skb->cb to stash LL addresses
zd1211rw: firmware needs duration_id set to zero for non-pspoll frames
net: enable TC35815 for MIPS again
...
Here are a few minor USB fixes and a bunch of device id updates for the
USB drivers.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-3.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
USB fixes for 3.3-rc3
Here are a few minor USB fixes and a bunch of device id updates for the
USB drivers.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tag 'usb-3.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
USB: usbserial: add new PID number (0xa951) to the ftdi driver
usb: ch9.h: usb_endpoint_maxp() uses __le16_to_cpu()
usb: musb: fix a build error on mips
uwb & wusb & usb wireless controllers: fix kconfig error & build errors
usb: Skip PCI USB quirk handling for Netlogic XLP
powerpc/usb: fix issue of CPU halt when missing USB PHY clock
usb: otg: mv_otg: Add dependence
usb: host: Distinguish Kconfig text for Freescale controllers
USB: add new zte 3g-dongle's pid to option.c
usb: ch9.h: usb_endpoint_maxp() uses __le16_to_cpu()
USB: qcserial: don't enable autosuspend
USB: qcserial: add several new serial devices
usb: otg: mv_otg: Add dependence
usb: gadget: zero: fix bug in loopback autoresume handling
The keeplocked variable in the cdrom driver is shared across multiple
drives, but set in per-device ioctls. Move it to the per-device struct,
avoiding that the setting on one drive affects the driver's behavior
when closing another.
[ Impact: limit udev's confusion to one drive when a CD burning program
unlocks the CD door at the end of burning. ]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Plug merge calls two elevator callbacks outside queue lock -
elevator_allow_merge_fn() and elevator_bio_merged_fn(). Although
attempt_plug_merge() suggests that elevator is guaranteed to be there
through the existing request on the plug list, nothing prevents plug
merge from calling into dying or initializing elevator.
For regular merges, bypass ensures elvpriv count to reach zero, which
in turn prevents merges as all !ELVPRIV requests get REQ_SOFTBARRIER
from forced back insertion. Plug merge doesn't check ELVPRIV, and, as
the requests haven't gone through elevator insertion yet, it doesn't
have SOFTBARRIER set allowing merges on a bypassed queue.
This, for example, leads to the following crash during elevator
switch.
BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
IP: [<ffffffff813b34e9>] cfq_allow_merge+0x49/0xa0
PGD 112cbc067 PUD 115d5c067 PMD 0
Oops: 0000 [#1] PREEMPT SMP
CPU 1
Modules linked in: deadline_iosched
Pid: 819, comm: dd Not tainted 3.3.0-rc2-work+ #76 Bochs Bochs
RIP: 0010:[<ffffffff813b34e9>] [<ffffffff813b34e9>] cfq_allow_merge+0x49/0xa0
RSP: 0018:ffff8801143a38f8 EFLAGS: 00010297
RAX: 0000000000000000 RBX: ffff88011817ce28 RCX: ffff880116eb6cc0
RDX: 0000000000000000 RSI: ffff880118056e20 RDI: ffff8801199512f8
RBP: ffff8801143a3908 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff880118195708
R13: ffff880118052aa0 R14: ffff8801143a3d50 R15: ffff880118195708
FS: 00007f19f82cb700(0000) GS:ffff88011fc80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 0000000000000008 CR3: 0000000112c6a000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process dd (pid: 819, threadinfo ffff8801143a2000, task ffff880116eb6cc0)
Stack:
ffff88011817ce28 ffff880118195708 ffff8801143a3928 ffffffff81391bba
ffff88011817ce28 ffff880118195708 ffff8801143a3948 ffffffff81391bf1
ffff88011817ce28 0000000000000000 ffff8801143a39a8 ffffffff81398e3e
Call Trace:
[<ffffffff81391bba>] elv_rq_merge_ok+0x4a/0x60
[<ffffffff81391bf1>] elv_try_merge+0x21/0x40
[<ffffffff81398e3e>] blk_queue_bio+0x8e/0x390
[<ffffffff81396a5a>] generic_make_request+0xca/0x100
[<ffffffff81396b04>] submit_bio+0x74/0x100
[<ffffffff811d45c2>] __blockdev_direct_IO+0x1ce2/0x3450
[<ffffffff811d0dc7>] blkdev_direct_IO+0x57/0x60
[<ffffffff811460b5>] generic_file_aio_read+0x6d5/0x760
[<ffffffff811986b2>] do_sync_read+0xe2/0x120
[<ffffffff81199345>] vfs_read+0xc5/0x180
[<ffffffff81199501>] sys_read+0x51/0x90
[<ffffffff81aeac12>] system_call_fastpath+0x16/0x1b
There are multiple ways to fix this including making plug merge check
ELVPRIV; however,
* Calling into elevator outside queue lock is confusing and
error-prone.
* Requests on plug list aren't known to the elevator. They aren't on
the elevator yet, so there's no elevator specific state to update.
* Given the nature of plug merges - collecting bio's for the same
purpose from the same issuer - elevator specific restrictions aren't
applicable.
So, simply don't call into elevator methods from plug merge by moving
elv_bio_merged() from bio_attempt_*_merge() to blk_queue_bio(), and
using blk_try_merge() in attempt_plug_merge().
This is based on Jens' patch to skip elevator_allow_merge_fn() from
plug merge.
Note that this makes per-cgroup merged stats skip plug merging.
Signed-off-by: Tejun Heo <tj@kernel.org>
LKML-Reference: <4F16F3CA.90904@kernel.dk>
Original-patch-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk_rq_merge_ok() is the elevator-neutral part of merge eligibility
test. blk_try_merge() determines merge direction and expects the
caller to have tested elv_rq_merge_ok() previously.
elv_rq_merge_ok() now wraps blk_rq_merge_ok() and then calls
elv_iosched_allow_merge(). elv_try_merge() is removed and the two
callers are updated to call elv_rq_merge_ok() explicitly followed by
blk_try_merge(). While at it, make rq_merge_ok() functions return
bool.
This is to prepare for plug merge update and doesn't introduce any
behavior change.
This is based on Jens' patch to skip elevator_allow_merge_fn() from
plug merge.
Signed-off-by: Tejun Heo <tj@kernel.org>
LKML-Reference: <4F16F3CA.90904@kernel.dk>
Original-patch-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/mfd-2.6:
mfd: Avoid twl6040-codec PLL reconfiguration when not needed
mfd: Store twl6040-codec mclk configuration
put_io_context() performed a complex trylock dancing to avoid
deferring ioc release to workqueue. It was also broken on UP because
trylock was always assumed to succeed which resulted in unbalanced
preemption count.
While there are ways to fix the UP breakage, even the most
pathological microbench (forced ioc allocation and tight fork/exit
loop) fails to show any appreciable performance benefit of the
optimization. Strip it out. If there turns out to be workloads which
are affected by this change, simpler optimization from the discussion
thread can be applied later.
Signed-off-by: Tejun Heo <tj@kernel.org>
LKML-Reference: <1328514611.21268.66.camel@sli10-conroe>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Setting the task name is done within setup_new_exec() by accessing
bprm->filename. However this happens after flush_old_exec().
This may result in a use after free bug, flush_old_exec() may
"complete" vfork_done, which will wake up the parent which in turn
may free the passed in filename.
To fix this add a new tcomm field in struct linux_binprm which
contains the now early generated task name until it is used.
Fixes this bug on s390:
Unable to handle kernel pointer dereference at virtual kernel address 0000000039768000
Process kworker/u:3 (pid: 245, task: 000000003a3dc840, ksp: 0000000039453818)
Krnl PSW : 0704000180000000 0000000000282e94 (setup_new_exec+0xa0/0x374)
Call Trace:
([<0000000000282e2c>] setup_new_exec+0x38/0x374)
[<00000000002dd12e>] load_elf_binary+0x402/0x1bf4
[<0000000000280a42>] search_binary_handler+0x38e/0x5bc
[<0000000000282b6c>] do_execve_common+0x410/0x514
[<0000000000282cb6>] do_execve+0x46/0x58
[<00000000005bce58>] kernel_execve+0x28/0x70
[<000000000014ba2e>] ____call_usermodehelper+0x102/0x140
[<00000000005bc8da>] kernel_thread_starter+0x6/0xc
[<00000000005bc8d4>] kernel_thread_starter+0x0/0xc
Last Breaking-Event-Address:
[<00000000002830f0>] setup_new_exec+0x2fc/0x374
Kernel panic - not syncing: Fatal exception: panic_on_oops
Reported-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Three power management regression fixes, one for a recent regression introcuded
by the freezer changes during the 3.3 merge window and two for regressions
in cpuidle (resulting from PM QoS changes) and in the hibernate user space
interface, both introduced during the 3.2 development cycle.
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Merge tag 'pm-fixes-for-3.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Power management fixes for 3.3-rc3
Three power management regression fixes, one for a recent regression introcuded
by the freezer changes during the 3.3 merge window and two for regressions
in cpuidle (resulting from PM QoS changes) and in the hibernate user space
interface, both introduced during the 3.2 development cycle.
They include:
* Two hibernate (s2disk) regression fixes from Srivatsa S. Bhat (for
regressions introduced during the 3.3 merge window and during the 3.2
development cycle).
* A cpuidle fix from Venki Pallipadi for a regression resulting from PM QoS
changes during the 3.2 development cycle causing cpuidle to work incorrectly
for CONFIG_PM unset.
* tag 'pm-fixes-for-3.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM / QoS: CPU C-state breakage with PM Qos change
PM / Freezer: Thaw only kernel threads if freezing of kernel threads fails
PM / Hibernate: Thaw kernel threads in SNAPSHOT_CREATE_IMAGE ioctl path
Looks like change "PM QoS: Move and rename the implementation files"
merged during the 3.2 development cycle made PM QoS depend on
CONFIG_PM which depends on (PM_SLEEP || PM_RUNTIME).
That breaks CPU C-states with kernels not having these CONFIGs, causing CPUs
to spend time in Polling loop idle instead of going into deep C-states,
consuming way way more power. This is with either acpi idle or intel idle
enabled.
Either CONFIG_PM should be enabled with any pm_qos users or
the !CONFIG_PM pm_qos_request() should return sane defaults not to break
the existing users. Here's is the patch for the latter option.
[rjw: Modified the changelog slightly.]
Signed-off-by: Venkatesh Pallipadi <venki@google.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: stable@vger.kernel.org
* 'fixes' of git://git.infradead.org/users/vkoul/slave-dma:
i.MX SDMA: Fix burstsize settings
ARM: mach-shmobile: both USB DMAC instances on sh7372 are slave-only
dma: sh_dma: not all SH DMAC implementations support MEMCPY
at_hdmac: bugfix for enabling channel irq
dmaengine: fix missing 'cnt' in ?: in dmatest
- Fix breakage with MTD suspend caused by the API rework
- Fix a problem with resetting the MX28 BCH module
- A couple of other trivial fixes
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Merge tag 'for-linus-3.3' of git://git.infradead.org/~dwmw2/mtd-3.3
- Fix a regression in 16-bit Atmel NAND flash which was introduced in 3.1
- Fix breakage with MTD suspend caused by the API rework
- Fix a problem with resetting the MX28 BCH module
- A couple of other trivial fixes
* tag 'for-linus-3.3-20120204' of git://git.infradead.org/~dwmw2/mtd-3.3:
Revert "mtd: atmel_nand: optimize read/write buffer functions"
mtd: fix MTD suspend
jffs2: do not initialize variable unnecessarily
mtd: gpmi-nand bugfix: reset the BCH module when it is not MX23
mtd: nand: fix typo in comment
Store the last used mclk configuration for the PLL.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
This fixes the race in process_vm_core found by Oleg (see
http://article.gmane.org/gmane.linux.kernel/1235667/
for details).
This has been updated since I last sent it as the creation of the new
mm_access() function did almost exactly the same thing as parts of the
previous version of this patch did.
In order to use mm_access() even when /proc isn't enabled, we move it to
kernel/fork.c where other related process mm access functions already
are.
Signed-off-by: Chris Yeoh <yeohc@au1.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There is a possible data corruption if an RNDIS message goes beyond page
boundary in the sending code path. This patch fixes the problem.
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
bugs, x86: Fix printk levels for panic, softlockups and stack dumps
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf top: Fix number of samples displayed
perf tools: Fix strlen() bug in perf_event__synthesize_event_type()
perf tools: Fix broken build by defining _GNU_SOURCE in Makefile
x86/dumpstack: Remove unneeded check in dump_trace()
perf: Fix broken interrupt rate throttling
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/rt: Fix task stack corruption under __ARCH_WANT_INTERRUPTS_ON_CTXSW
sched: Fix ancient race in do_exit()
sched/nohz: Fix nohz cpu idle load balancing state with cpu hotplug
sched/s390: Fix compile error in sched/core.c
sched: Fix rq->nr_uninterruptible update race
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/reboot: Remove VersaLogic Menlow reboot quirk
x86/reboot: Skip DMI checks if reboot set by user
x86: Properly parenthesize cmpxchg() macro arguments
* 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
lib: Fix 32-bit sparc udiv_qrnnd() definition in mpilib's longlong.h
lib: Fix multiple definitions of clz_tab
lib/digsig: checks for NULL return value
lib/mpi: added missing NULL check
lib/mpi: added comment on divide by 0 case
lib/mpi: check for possible zero length
lib/digsig: pkcs_1_v1_5_decode_emsa cleanup
lib/digsig: additional sanity checks against badly formated key payload
lib/mpi: removed unused functions
lib/mpi: checks for zero divisor length
lib/mpi: return error code on dividing by zero
lib/mpi: replaced MPI_NULL with normal NULL
lib/mpi: added missing NULL check
The usb/ch9.h will be installed to /usr/include/linux,
and be used from user space.
But le16_to_cpu() is only defined for kernel code.
Without this patch, user space compile will be broken.
Special thanks to Stefan Becker
Reported-by: Stefan Becker <chemobejk@gmail.com>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch fixes merge conflict resolution breakage introduced by merge
d3712b9dfc ("Merge tag 'for-linus' of git://github.com/prasad-joshi/logfs_upstream").
The commit changed 'mtd_can_have_bb()' function and made it always
return zero, which is incorrect. Instead, we need it to return whether
the underlying flash device can have bad eraseblocks or not. UBI needs
this information because it affects how it handles the underlying flash.
E.g., if the underlying flash is NOR, it cannot have bad blocks and any
write or erase error is fatal, and all we can do is to switch to R/O
mode. We do not need to reserve a pool of good eraseblocks for bad
eraseblocks handling, and so on.
This patch also removes 'mtd_can_have_bb()' invocations from Logfs to
ensure correct Logfs behavior.
I've tested that with this patch UBI works on top of NOR and NAND
flashes emulated by mtdram and nandsim correspondingly.
This patch is based on patch from Linus Torvalds.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Acked-by: Jörn Engel <joern@logfs.org>
Acked-by: Prasad Joshi <prasadjoshi.linux@gmail.com>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A struct device parameter is used in the enable and disable callbacks to
distinguish between different gpio_keys devices.
Platforms that don't use these callbacks may not include struct device
at all, as seen on arch/arm/mach-s3c2410/mach-n30.c
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Add a flag to allow platforms to specify, whether a DMAC instance supports
the MEMCPY operation. To avoid regressions, preserve the current default.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
MPI_NULL is replaced with normal NULL.
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Reviewed-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
PROP_MAX_SHIFT should be set to <=32 on 64-bit box. This fixes two bugs
in the below lines of bdi_dirty_limit():
bdi_dirty *= numerator;
do_div(bdi_dirty, denominator);
1) divide error: do_div() only uses the lower 32 bit of the denominator,
which may trimmed to be 0 when PROP_MAX_SHIFT > 32.
2) overflow: (bdi_dirty * numerator) could easily overflow if numerator
used up to 48 bits, leaving only 16 bits to bdi_dirty
Cc: <stable@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reported-by: Ilya Tumaykin <librarian_rus@yahoo.com>
Tested-by: Ilya Tumaykin <librarian_rus@yahoo.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
There are few important bug fixes for LogFS
Shortlog:
Joern Engel (5):
logfs: Prevent memory corruption
logfs: remove useless BUG_ON
logfs: Free areas before calling generic_shutdown_super()
logfs: Grow inode in delete path
Logfs: Allow NULL block_isbad() methods
Prasad Joshi (5):
logfs: update page reference count for pined pages
logfs: take write mutex lock during fsync and sync
logfs: set superblock shutdown flag after generic sb shutdown
logfs: Propagate page parameter to __logfs_write_inode
MAINTAINERS: Add Prasad Joshi in LogFS maintiners
Diffstat:
MAINTAINERS | 1 +
fs/logfs/dev_mtd.c | 26 +++++++++++-------------
fs/logfs/dir.c | 2 +-
fs/logfs/file.c | 2 +
fs/logfs/gc.c | 2 +-
fs/logfs/inode.c | 4 ++-
fs/logfs/journal.c | 1 -
fs/logfs/logfs.h | 5 +++-
fs/logfs/readwrite.c | 51 +++++++++++++++++++++++++++++++++----------------
fs/logfs/segment.c | 51 ++++++++++++++++++++++++++++++++++++++-----------
fs/logfs/super.c | 3 +-
11 files changed, 99 insertions(+), 49 deletions(-)
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Merge tag 'for-linus' of git://github.com/prasad-joshi/logfs_upstream
There are few important bug fixes for LogFS
* tag 'for-linus' of git://github.com/prasad-joshi/logfs_upstream:
Logfs: Allow NULL block_isbad() methods
logfs: Grow inode in delete path
logfs: Free areas before calling generic_shutdown_super()
logfs: remove useless BUG_ON
MAINTAINERS: Add Prasad Joshi in LogFS maintiners
logfs: Propagate page parameter to __logfs_write_inode
logfs: set superblock shutdown flag after generic sb shutdown
logfs: take write mutex lock during fsync and sync
logfs: Prevent memory corruption
logfs: update page reference count for pined pages
Fix up conflict in fs/logfs/dev_mtd.c due to semantic change in what
"mtd->block_isbad" means in commit f2933e86ad: "Logfs: Allow NULL
block_isbad() methods" clashing with the abstraction changes in the
commits 7086c19d07: "mtd: introduce mtd_block_isbad interface" and
d58b27ed58: "logfs: do not use 'mtd->block_isbad' directly".
This resolution takes the semantics from commit f2933e86ad, and just
makes mtd_block_isbad() return zero (false) if the 'block_isbad'
function is NULL. But that also means that now "mtd_can_have_bb()"
always returns 0.
Now, "mtd_block_markbad()" will obviously return an error if the
low-level driver doesn't support bad blocks, so this is somewhat
non-symmetric, but it actually makes sense if a NULL "block_isbad"
function is considered to mean "I assume that all my blocks are always
good".
Nothing major, largest thing here is the removal of some drivers that
did not work at all. Other than that, the normal collection of bugfixes
and new device ids.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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Merge tag 'usb-3.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Here are a bunch of USB patches for 3.3-rc1.
Nothing major, largest thing here is the removal of some drivers that
did not work at all. Other than that, the normal collection of bugfixes
and new device ids.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* tag 'usb-3.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (52 commits)
uwb & wusb: fix kconfig error
USB: Realtek cr: fix autopm scheduling while atomic
USB: ftdi_sio: Add more identifiers
xHCI: Cleanup isoc transfer ring when TD length mismatch found
usb: musb: omap2430: minor cleanups.
qcaux: add more Pantech UML190 and UML290 ports
Revert "drivers: usb: Fix dependency for USB_HWA_HCD"
usb: mv-otg - Fix build if CONFIG_USB is not set
USB: cdc-wdm: Avoid hanging on interface with no USB_CDC_DMM_TYPE
usb: add support for STA2X11 host driver
drivers: usb: Fix dependency for USB_HWA_HCD
kernel-doc: fix new warning in usb.h
USB: OHCI: fix new compiler warnings
usb: serial: kobil_sct: fix compile warning:
drivers/usb/host/ehci-fsl.c: add missing iounmap
USB: cdc-wdm: better allocate a buffer that is at least as big as we tell the USB core
USB: cdc-wdm: call wake_up_all to allow driver to shutdown on device removal
USB: cdc-wdm: use two mutexes to allow simultaneous read and write
USB: cdc-wdm: updating desc->length must be protected by spin_lock
USB: usbsevseg: fix max length
...
Commits 3fe4bae884 and
079c985e7a broke MTD suspend in 2 ways:
1. When the '->suspend' method is not present, we return -EOPNOTSUPP, but
the callers of 'mtd_suspend()' expects 0 instead.
2. Checking of the 'mtd' parameter against NULL has been incorrectly removed
in 'mtd_cls_suspend()'.
This patch fixes the breakages. This has been found, analyzed, reported
and tested by Rafael J. Wysocki <rjw@sisk.pl>.
Note, this patch is not needed in the stable tree because it causes a
regression introduced during the v3.3 merge window.
Reported-by: Rafael J. Wysocki <rjw@sisk.pl>
Tested-by: Rafael J. Wysocki <rjw@sisk.pl>
Tested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Commit 2aede851dd
PM / Hibernate: Freeze kernel threads after preallocating memory
introduced a mechanism by which kernel threads were frozen after
the preallocation of hibernate image memory to avoid problems with
frozen kernel threads not responding to memory freeing requests.
However, it overlooked the s2disk code path in which the
SNAPSHOT_CREATE_IMAGE ioctl was run directly after SNAPSHOT_FREE,
which caused freeze_workqueues_begin() to BUG(), because it saw
that worqueues had been already frozen.
Although in principle this issue might be addressed by removing
the relevant BUG_ON() from freeze_workqueues_begin(), that would
reintroduce the very problem that commit 2aede851dd
attempted to avoid into that particular code path. For this reason,
to fix the issue at hand, introduce thaw_kernel_threads() and make
the SNAPSHOT_FREE ioctl execute it.
Special thanks to Srivatsa S. Bhat for detailed analysis of the
problem.
Reported-and-tested-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: stable@kernel.org
It contains the removal of the sysdev code, now that all users of it are
gone, as well as some sysfs bugfixes that have been reported by users.
There are also some documentation updates here as well.
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Merge tag 'driver-core-3.3-rc1-bugfixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Here are some patches for the 3.3-rc1 tree.
It contains the removal of the sysdev code, now that all users of it are
gone, as well as some sysfs bugfixes that have been reported by users.
There are also some documentation updates here as well.
* tag 'driver-core-3.3-rc1-bugfixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
sysfs: Complain bitterly about attempts to remove files from nonexistent directories.
stable: update documentation to ask for kernel version
base/core.c:fix typo in comment in function device_add
Documentation: devres: add allocation functions to list of supported calls
Documentation update for the driver model core
kernel-doc: fix new warnings in driver-core
kernel-doc: fix new warnings in debugfs
kernel-doc: fix new warnings in device.h
driver core: remove drivers/base/sys.c and include/linux/sysdev.h
* 'fixes' of git://git.linaro.org/people/rmk/linux-arm: (31 commits)
ARM: 7304/1: ioremap: fix boundary check when reusing static mapping
ARM: 7301/1: Rename the T() macro to TUSER() to avoid namespace conflicts
ARM: 7299/1: ftrace: clear zero bit in reported IPs for Thumb-2
ARM: 7298/1: realview: fix mapping of MPCore private memory region
PCMCIA: fix sa1111 oops on remove
ARM: 7288/1: mach-sa1100: add missing module_init() call
ARM: 7297/1: smp_twd: make sure timer is stopped before registering it
ARM: 7296/1: proc-v7.S: remove HARVARD_CACHE preprocessor guards
ARM: 7295/1: cortex-a7: move proc_info out of !CONFIG_ARM_LPAE block
ARM: 7293/1: logical_cpu_map: decouple CPU mapping from SMP
ARM: 7291/1: cache: assume 64-byte L1 cachelines for ARMv7 CPUs
ARM: 7290/1: vmlinux.lds.S: align the exception fixup table to a 4-byte boundary
ARM: 7289/1: vmlinux.lds.S: do not hardcode cacheline size as 32 bytes
MFD: ucb1x00-ts: fix resume failure
MFD: ucb1x00-core: fix gpiolib direction_output handling
MFD: ucb1x00-core: fix missing restore of io output data on resume
MFD: mcp-core: fix mcp_priv() to be more type safe
MFD: mcp-core: fix complaints from the genirq layer
Revert "ARM: sa11x0: Implement autoloading of codec and codec pdata for mcp bus."
Revert "ARM: sa1100: Refactor mcp-sa11x0 to use platform resources."
...
Fix up conflict due to arch/arm/mach-mx5/Kconfig having been merged into
mach-imx5 (commit 784a90c0a7: "ARM i.MX: Merge i.MX5 support into
mach-imx"), but the ARM_L1_CACHE_SHIFT_6 entry was moved to be driven by
the CPU_V7 logic from it in the old location in rmk's branch (commit
a092f2b153: "ARM: 7291/1: cache: assume 64-byte L1 cachelines for
ARMv7 CPUs").
This patch fixes the sampling interrupt throttling mechanism.
It was broken in v3.2. Events were not being unthrottled. The
unthrottling mechanism required that events be checked at each
timer tick.
This patch solves this problem and also separates:
- unthrottling
- multiplexing
- frequency-mode period adjustments
Not all of them need to be executed at each timer tick.
This third version of the patch is based on my original patch +
PeterZ proposal (https://lkml.org/lkml/2012/1/7/87).
At each timer tick, for each context:
- if the current CPU has throttled events, we unthrottle events
- if context has frequency-based events, we adjust sampling periods
- if we have reached the jiffies interval, we multiplex (rotate)
We decoupled rotation (multiplexing) from frequency-mode sampling
period adjustments. They should not necessarily happen at the same
rate. Multiplexing is subject to jiffies_interval (currently at 1
but could be higher once the tunable is exposed via sysfs).
We have grouped frequency-mode adjustment and unthrottling into the
same routine to minimize code duplication. When throttled while in
frequency mode, we scan the events only once.
We have fixed the threshold enforcement code in __perf_event_overflow().
There was a bug whereby it would allow more than the authorized rate
because an increment of hwc->interrupts was not executed at the right
place.
The patch was tested with low sampling limit (2000) and fixed periods,
frequency mode, overcommitted PMU.
On a 2.1GHz AMD CPU:
$ cat /proc/sys/kernel/perf_event_max_sample_rate
2000
We set a rate of 3000 samples/sec (2.1GHz/3000 = 700000):
$ perf record -e cycles,cycles -c 700000 noploop 10
$ perf report -D | tail -21
Aggregated stats:
TOTAL events: 80086
MMAP events: 88
COMM events: 2
EXIT events: 4
THROTTLE events: 19996
UNTHROTTLE events: 19996
SAMPLE events: 40000
cycles stats:
TOTAL events: 40006
MMAP events: 5
COMM events: 1
EXIT events: 4
THROTTLE events: 9998
UNTHROTTLE events: 9998
SAMPLE events: 20000
cycles stats:
TOTAL events: 39996
THROTTLE events: 9998
UNTHROTTLE events: 9998
SAMPLE events: 20000
For 10s, the cap is 2x2000x10 = 40000 samples.
We get exactly that: 20000 samples/event.
Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: <stable@kernel.org> # v3.2+
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20120126160319.GA5655@quad
Signed-off-by: Ingo Molnar <mingo@elte.hu>