Sarah Sharp [Thu, 1 Nov 2012 18:20:44 +0000 (11:20 -0700)]
USB: Rip out recursive call on warm port reset.
When a hot reset fails on a USB 3.0 port, the current port reset code
recursively calls hub_port_reset inside hub_port_wait_reset. This isn't
ideal, since we should avoid recursive calls in the kernel, and it also
doesn't allow us to issue multiple warm resets on reset failures.
Rip out the recursive call. Instead, add code to hub_port_reset to
issue a warm reset if the hot reset fails, and try multiple warm resets
before giving up on the port.
In hub_port_wait_reset, remove the recursive call and re-indent. The
code is basically the same, except:
1. It bails out early if the port has transitioned to Inactive or
Compliance Mode after the reset completed.
2. It doesn't consider a connect status change to be a failed reset. If
multiple warm resets needed to be issued, the connect status may have
changed, so we need to ignore that and look at the port link state
instead. hub_port_reset will now do that.
3. It unconditionally sets udev->speed on all types of successful
resets. The old recursive code would set the port speed when the second
hub_port_reset returned.
The old code did not handle connected devices needing a warm reset well.
There were only two situations that the old code handled correctly: an
empty port needing a warm reset, and a hot reset that migrated to a warm
reset.
When an empty port needed a warm reset, hub_port_reset was called with
the warm variable set. The code in hub_port_finish_reset would skip
telling the USB core and the xHC host that the device was reset, because
otherwise that would result in a NULL pointer dereference.
When a USB 3.0 device reset migrated to a warm reset, the recursive call
made the call stack look like this:
hub_port_reset(warm = false)
hub_wait_port_reset(warm = false)
hub_port_reset(warm = true)
hub_wait_port_reset(warm = true)
hub_port_finish_reset(warm = true)
(return up the call stack to the first wait)
hub_port_finish_reset(warm = false)
The old code didn't want to notify the USB core or the xHC host of device reset
twice, so it only did it in the second call to hub_port_finish_reset,
when warm was set to false. This was necessary because
before patch two ("USB: Ignore xHCI Reset Device status."), the USB core
would pay attention to the xHC Reset Device command error status, and
the second call would always fail.
Now that we no longer have the recursive call, and warm can change from
false to true in hub_port_reset, we need to have hub_port_finish_reset
unconditionally notify the USB core and the xHC of the device reset.
In hub_port_finish_reset, unconditionally clear the connect status
change (CSC) bit for USB 3.0 hubs when the port reset is done. If we
had to issue multiple warm resets for a device, that bit may have been
set if the device went into SS.Inactive and then was successfully warm
reset.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu>
Sarah Sharp [Tue, 4 Dec 2012 23:27:50 +0000 (15:27 -0800)]
USB: Prepare for refactoring by adding extra udev checks.
The next patch will refactor the hub port code to rip out the recursive
call to hub_port_reset on a failed hot reset. In preparation for that,
make sure all code paths can deal with being called with a NULL udev.
The usb_device will not be valid if warm reset was issued because a port
transitioned to the Inactive or Compliance Mode on a device connect.
This patch should have no effect on current behavior.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu>
Sarah Sharp [Thu, 1 Nov 2012 18:20:44 +0000 (11:20 -0700)]
USB: Don't use EHCI port sempahore for USB 3.0 hubs.
The EHCI host controller needs to prevent EHCI initialization when the
UHCI or OHCI companion controller is in the middle of a port reset. It
uses ehci_cf_port_reset_rwsem to do this. USB 3.0 hubs can't be under
an EHCI host controller, so it makes no sense to down the semaphore for
USB 3.0 hubs. It also makes the warm port reset code more complex.
Don't down ehci_cf_port_reset_rwsem for USB 3.0 hubs.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu>
Sarah Sharp [Tue, 27 Nov 2012 20:30:23 +0000 (12:30 -0800)]
xhci: Avoid "dead ports", add roothub port polling.
The USB core hub thread (khubd) is designed with external USB hubs in
mind. It expects that if a port status change bit is set, the hub will
continue to send a notification through the hub status data transfer.
Basically, it expects hub notifications to be level-triggered.
The xHCI host controller is designed to be edge-triggered on the logical
'OR' of all the port status change bits. When all port status change
bits are clear, and a new change bit is set, the xHC will generate a
Port Status Change Event. If another change bit is set in the same port
status register before the first bit is cleared, it will not send
another event.
This means that the hub code may lose port status changes because of
race conditions between clearing change bits. The user sees this as a
"dead port" that doesn't react to device connects.
The fix is to turn on port polling whenever a new change bit is set.
Once the USB core issues a hub status request that shows that no change
bits are set in any USB ports, turn off port polling.
We can't allow the USB core to poll the roothub for port events during
host suspend because if the PCI host is in D3cold, the port registers
will be all f's. Instead, stop the port polling timer, and
unconditionally restart it when the host resumes. If there are no port
change bits set after the resume, the first call to hub_status_data will
disable polling.
This patch should be backported to stable kernels with the first xHCI
support, 2.6.31 and newer, that include the commit 0f2a79300a1471cf92ab43af165ea13555c8b0a5 "USB: xhci: Root hub support."
There will be merge conflicts because the check for HC_STATE_SUSPENDED
was moved into xhci_suspend in 3.8.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Cc: stable@vger.kernel.org
Sarah Sharp [Thu, 15 Nov 2012 01:58:04 +0000 (17:58 -0800)]
USB: Handle warm reset failure on empty port.
An empty port can transition to either Inactive or Compliance Mode if a
newly connected USB 3.0 device fails to link train. In that case, we
issue a warm reset. Some devices, such as John's Roseweil eusb3
enclosure, slip back into Compliance Mode after the warm reset.
The current warm reset code does not check for device connect status on
warm reset completion, and it incorrectly reports the warm reset
succeeded. This causes the USB core to attempt to send a Set Address
control transfer to a port in Compliance Mode, which will always fail.
Make hub_port_wait_reset check the current connect status and link state
after the warm reset completes. Return a failure status if the device
is disconnected or the link state is Compliance Mode or SS.Inactive.
Make hub_events disable the port if warm reset fails. This will disable
the port, and then bring it back into the RxDetect state. Make the USB
core ignore the connect change until the device reconnects.
Note that this patch does NOT handle connected devices slipping into the
Inactive state very well. This is a concern, because devices can go
into the Inactive state on U1/U2 exit failure. However, the fix for
that case is too large for stable, so it will be submitted in a separate
patch.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: John Covici <covici@ccs.covici.com> Cc: stable@vger.kernel.org
Sarah Sharp [Thu, 15 Nov 2012 22:58:04 +0000 (14:58 -0800)]
USB: Ignore port state until reset completes.
The port reset code bails out early if the current connect status is
cleared (device disconnected). If we're issuing a hot reset, it may
also look at the link state before the reset is finished.
Section 10.14.2.6 of the USB 3.0 spec says that when a port enters the
Error state or Resetting state, the port connection bit retains the
value from the previous state. Therefore we can't trust it until the
reset finishes. Also, the xHCI spec section 4.19.1.2.5 says software
shall ignore the link state while the port is resetting, as it can be in
an unknown state.
The port state during reset is also unknown for USB 2.0 hubs. The hub
sends a reset signal by driving the bus into an SE0 state. This
overwhelms the "connect" signal from the device, so the port can't tell
whether anything is connected or not.
Fix the port reset code to ignore the port link state and current
connect bit until the reset finishes, and USB_PORT_STAT_RESET is
cleared.
Remove the check for USB_PORT_STAT_C_BH_RESET in the warm reset case,
because it's redundant. When the warm reset finishes, the port reset
bit will be cleared at the same time USB_PORT_STAT_C_BH_RESET is set.
Remove the now-redundant check for a cleared USB_PORT_STAT_RESET bit
in the code to deal with the finished reset.
This patch should be backported to all stable kernels.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Cc: stable@vger.kernel.org
Sarah Sharp [Thu, 15 Nov 2012 01:16:52 +0000 (17:16 -0800)]
USB: Increase reset timeout.
John's NEC 0.96 xHCI host controller needs a longer timeout for a warm
reset to complete. The logs show it takes 650ms to complete the warm
reset, so extend the hub reset timeout to 800ms to be on the safe side.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: John Covici <covici@ccs.covici.com> Cc: stable@vger.kernel.org
Sarah Sharp [Thu, 15 Nov 2012 00:42:32 +0000 (16:42 -0800)]
USB: Allow USB 3.0 ports to be disabled.
If hot and warm reset fails, or a port remains in the Compliance Mode,
the USB core needs to be able to disable a USB 3.0 port. Unlike USB 2.0
ports, once the port is placed into the Disabled link state, it will not
report any new device connects. To get device connect notifications, we
need to put the link into the Disabled state, and then the RxDetect
state.
The xHCI driver needs to atomically clear all change bits on USB 3.0
port disable, so that we get Port Status Change Events for future port
changes. We could technically do this in the USB core instead of in the
xHCI roothub code, since the port state machine can't advance out of the
disabled state until we set the link state to RxDetect. However,
external USB 3.0 hubs don't need this code. They are level-triggered,
not edge-triggered like xHCI, so they will continue to send interrupt
events when any change bit is set. Therefore it doesn't make sense to
put this code in the USB core.
This patch is part of a series to fix several reports of infinite loops
on device enumeration failure. This includes John, when he boots with
a USB 3.0 device (Roseweil eusb3 enclosure) attached to his NEC 0.96
host controller. The fix requires warm reset support, so it does not
make sense to backport this patch to stable kernels without warm reset
support.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: John Covici <covici@ccs.covici.com> Cc: stable@vger.kernel.org
Sarah Sharp [Thu, 15 Nov 2012 00:10:49 +0000 (16:10 -0800)]
USB: Ignore xHCI Reset Device status.
When the USB core finishes reseting a USB device, the xHCI driver sends
a Reset Device command to the host. The xHC then updates its internal
representation of the USB device to the 'Default' device state. If the
device was already in the Default state, the xHC will complete the
command with an error status.
If a device needs to be reset several times during enumeration, the
second reset will always fail because of the xHCI Reset Device command.
This can cause issues during enumeration.
For example, usb_reset_and_verify_device calls into hub_port_init in a
loop. Say that on the first call into hub_port_init, the device is
successfully reset, but doesn't respond to several set address control
transfers. Then the port will be disabled, but the udev will remain in
tact. usb_reset_and_verify_device will call into hub_port_init again.
On the second call into hub_port_init, the device will be reset, and the
xHCI driver will issue a Reset Device command. This command will fail
(because the device is already in the Default state), and
usb_reset_and_verify_device will fail. The port will be disabled, and
the device won't be able to enumerate.
Fix this by ignoring the return value of the HCD reset_device callback.
Sarah Sharp [Wed, 14 Nov 2012 23:58:52 +0000 (15:58 -0800)]
USB: Handle auto-transition from hot to warm reset.
USB 3.0 hubs and roothubs will automatically transition a failed hot
reset to a warm (BH) reset. In that case, the warm reset change bit
will be set, and the link state change bit may also be set. Change
hub_port_finish_reset to unconditionally clear those change bits for USB
3.0 hubs. If these bits are not cleared, we may lose port change events
from the roothub.
Sarah Sharp [Mon, 17 Dec 2012 22:12:35 +0000 (14:12 -0800)]
xhci: Handle HS bulk/ctrl endpoints that don't NAK.
A high speed control or bulk endpoint may have bInterval set to zero,
which means it does not NAK. If bInterval is non-zero, it means the
endpoint NAKs at a rate of 2^(bInterval - 1).
The xHCI code to compute the NAK interval does not handle the special
case of zero properly. The current code unconditionally subtracts one
from bInterval and uses it as an exponent. This causes a very large
bInterval to be used, and warning messages like these will be printed:
usb 1-1: ep 0x1 - rounding interval to 32768 microframes, ep desc says 0 microframes
This may cause the xHCI host hardware to reject the Configure Endpoint
command, which means the HS device will be unusable under xHCI ports.
This patch should be backported to kernels as old as 2.6.31, that contain
commit dfa49c4ad120a784ef1ff0717168aa79f55a483a "USB: xhci - fix math in
xhci_get_endpoint_interval()".
Reported-by: Vincent Pelletier <plr.vincent@gmail.com> Suggested-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: stable@vger.kernel.org
Linus Torvalds [Sat, 22 Dec 2012 01:10:29 +0000 (17:10 -0800)]
Merge git://www.linux-watchdog.org/linux-watchdog
Pull watchdog updates from Wim Van Sebroeck:
"This includes some fixes and code improvements (like
clk_prepare_enable and clk_disable_unprepare), conversion from the
omap_wdt and twl4030_wdt drivers to the watchdog framework, addition
of the SB8x0 chipset support and the DA9055 Watchdog driver and some
OF support for the davinci_wdt driver."
* git://www.linux-watchdog.org/linux-watchdog: (22 commits)
watchdog: mei: avoid oops in watchdog unregister code path
watchdog: Orion: Fix possible null-deference in orion_wdt_probe
watchdog: sp5100_tco: Add SB8x0 chipset support
watchdog: davinci_wdt: add OF support
watchdog: da9052: Fix invalid free of devm_ allocated data
watchdog: twl4030_wdt: Change TWL4030_MODULE_PM_RECEIVER to TWL_MODULE_PM_RECEIVER
watchdog: remove depends on CONFIG_EXPERIMENTAL
watchdog: Convert dev_printk(KERN_<LEVEL> to dev_<level>(
watchdog: DA9055 Watchdog driver
watchdog: omap_wdt: eliminate goto
watchdog: omap_wdt: delete redundant platform_set_drvdata() calls
watchdog: omap_wdt: convert to devm_ functions
watchdog: omap_wdt: convert to new watchdog core
watchdog: WatchDog Timer Driver Core: fix comment
watchdog: s3c2410_wdt: use clk_prepare_enable and clk_disable_unprepare
watchdog: imx2_wdt: Select the driver via ARCH_MXC
watchdog: cpu5wdt.c: add missing del_timer call
watchdog: hpwdt.c: Increase version string
watchdog: Convert twl4030_wdt to watchdog core
davinci_wdt: preparation for switch to common clock framework
...
Linus Torvalds [Sat, 22 Dec 2012 01:09:07 +0000 (17:09 -0800)]
Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6
Pull CIFS fixes from Steve French:
"Misc small cifs fixes"
* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
cifs: eliminate cifsERROR variable
cifs: don't compare uniqueids in cifs_prime_dcache unless server inode numbers are in use
cifs: fix double-free of "string" in cifs_parse_mount_options
Linus Torvalds [Sat, 22 Dec 2012 01:08:06 +0000 (17:08 -0800)]
Merge tag 'dm-3.8-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm
Pull dm update from Alasdair G Kergon:
"Miscellaneous device-mapper fixes, cleanups and performance
improvements.
Of particular note:
- Disable broken WRITE SAME support in all targets except linear and
striped. Use it when kcopyd is zeroing blocks.
- Remove several mempools from targets by moving the data into the
bio's new front_pad area(which dm calls 'per_bio_data').
- Fix a race in thin provisioning if discards are misused.
- Prevent userspace from interfering with the ioctl parameters and
use kmalloc for the data buffer if it's small instead of vmalloc.
- Throttle some annoying error messages when I/O fails."
* tag 'dm-3.8-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm: (36 commits)
dm stripe: add WRITE SAME support
dm: remove map_info
dm snapshot: do not use map_context
dm thin: dont use map_context
dm raid1: dont use map_context
dm flakey: dont use map_context
dm raid1: rename read_record to bio_record
dm: move target request nr to dm_target_io
dm snapshot: use per_bio_data
dm verity: use per_bio_data
dm raid1: use per_bio_data
dm: introduce per_bio_data
dm kcopyd: add WRITE SAME support to dm_kcopyd_zero
dm linear: add WRITE SAME support
dm: add WRITE SAME support
dm: prepare to support WRITE SAME
dm ioctl: use kmalloc if possible
dm ioctl: remove PF_MEMALLOC
dm persistent data: improve improve space map block alloc failure message
dm thin: use DMERR_LIMIT for errors
...
This is obviously wrong, and I have no idea how I missed seeing the
warning in testing: I must just not have looked at the right logs. The
caller bumps rq_resused/rq_next_page, so it will always be hit on a
large enough read.
Reported-by: Dave Jones <davej@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Sat, 22 Dec 2012 00:40:26 +0000 (16:40 -0800)]
Merge tag 'rdma-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband
Pull more infiniband changes from Roland Dreier:
"Second batch of InfiniBand/RDMA changes for 3.8:
- cxgb4 changes to fix lookup engine hash collisions
- mlx4 changes to make flow steering usable
- fix to IPoIB to avoid pinning dst reference for too long"
* tag 'rdma-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband:
RDMA/cxgb4: Fix bug for active and passive LE hash collision path
RDMA/cxgb4: Fix LE hash collision bug for passive open connection
RDMA/cxgb4: Fix LE hash collision bug for active open connection
mlx4_core: Allow choosing flow steering mode
mlx4_core: Adjustments to Flow Steering activation logic for SR-IOV
mlx4_core: Fix error flow in the flow steering wrapper
mlx4_core: Add QPN enforcement for flow steering rules set by VFs
cxgb4: Add LE hash collision bug fix path in LLD driver
cxgb4: Add T4 filter support
IPoIB: Call skb_dst_drop() once skb is enqueued for sending
Linus Torvalds [Sat, 22 Dec 2012 00:39:08 +0000 (16:39 -0800)]
Merge tag 'asm-generic' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic
Pull asm-generic cleanup from Arnd Bergmann:
"These are a few cleanups for asm-generic:
- a set of patches from Lars-Peter Clausen to generalize asm/mmu.h
and use it in the architectures that don't need any special
handling.
- A patch from Will Deacon to remove the {read,write}s{b,w,l} as
discussed during the arm64 review
- A patch from James Hogan that helps with the meta architecture
series."
* tag 'asm-generic' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
xtensa: Use generic asm/mmu.h for nommu
h8300: Use generic asm/mmu.h
c6x: Use generic asm/mmu.h
asm-generic/mmu.h: Add support for FDPIC
asm-generic/mmu.h: Remove unused vmlist field from mm_context_t
asm-generic: io: remove {read,write} string functions
asm-generic/io.h: remove asm/cacheflush.h include
Kukjin Kim [Fri, 21 Dec 2012 18:02:13 +0000 (10:02 -0800)]
ARM: dts: fix duplicated build target and alphabetical sort out for exynos
Commit db5b0ae00712 ("Merge tag 'dt' of git://git.kernel.org/.../arm-soc")
causes a duplicated build target. This patch fixes it and sorts out the
build target alphabetically so that we can recognize something wrong
easily.
Cc: Olof Johansson <olof@lixom.net> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mikulas Patocka [Fri, 21 Dec 2012 20:23:41 +0000 (20:23 +0000)]
dm snapshot: do not use map_context
Eliminate struct map_info from dm-snap.
map_info->ptr was used in dm-snap to indicate if the bio was tracked.
If map_info->ptr was non-NULL, the bio was linked in tracked_chunk_hash.
This patch removes the use of map_info->ptr. We determine if the bio was
tracked based on hlist_unhashed(&c->node). If hlist_unhashed is true,
the bio is not tracked, if it is false, the bio is tracked.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mikulas Patocka [Fri, 21 Dec 2012 20:23:40 +0000 (20:23 +0000)]
dm raid1: dont use map_context
Don't use map_info any more in dm-raid1.
map_info was used for writes to hold the region number. For this purpose
we add a new field dm_bio_details to dm_raid1_bio_record.
map_info was used for reads to hold a pointer to dm_raid1_bio_record (if
the pointer was non-NULL, bio details were saved; if the pointer was
NULL, bio details were not saved). We use
dm_raid1_bio_record.details->bi_bdev for this purpose. If bi_bdev is
NULL, details were not saved, if bi_bdev is non-NULL, details were
saved.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mikulas Patocka [Fri, 21 Dec 2012 20:23:38 +0000 (20:23 +0000)]
dm: introduce per_bio_data
Introduce a field per_bio_data_size in struct dm_target.
Targets can set this field in the constructor. If a target sets this
field to a non-zero value, "per_bio_data_size" bytes of auxiliary data
are allocated for each bio submitted to the target. These data can be
used for any purpose by the target and help us improve performance by
removing some per-target mempools.
Per-bio data is accessed with dm_per_bio_data. The
argument data_size must be the same as the value per_bio_data_size in
dm_target.
If the target has a pointer to per_bio_data, it can get a pointer to
the bio with dm_bio_from_per_bio_data() function (data_size must be the
same as the value passed to dm_per_bio_data).
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mike Snitzer [Fri, 21 Dec 2012 20:23:37 +0000 (20:23 +0000)]
dm kcopyd: add WRITE SAME support to dm_kcopyd_zero
Add WRITE SAME support to dm-io and make it accessible to
dm_kcopyd_zero(). dm_kcopyd_zero() provides an asynchronous interface
whereas the blkdev_issue_write_same() interface is synchronous.
WRITE SAME is a SCSI command that can be leveraged for more efficient
zeroing of a specified logical extent of a device which supports it.
Only a single zeroed logical block is transfered to the target for each
WRITE SAME and the target then writes that same block across the
specified extent.
The dm thin target uses this.
Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mike Snitzer [Fri, 21 Dec 2012 20:23:37 +0000 (20:23 +0000)]
dm: add WRITE SAME support
WRITE SAME bios have a payload that contain a single page. When
cloning WRITE SAME bios DM has no need to modify the bi_io_vec
attributes (and doing so would be detrimental). DM need only alter the
start and end of the WRITE SAME bio accordingly.
Rather than duplicate __clone_and_map_discard, factor out a common
function that is also used by __clone_and_map_write_same.
Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mikulas Patocka [Fri, 21 Dec 2012 20:23:36 +0000 (20:23 +0000)]
dm ioctl: use kmalloc if possible
If the parameter buffer is small enough, try to allocate it with kmalloc()
rather than vmalloc().
vmalloc is noticeably slower than kmalloc because it has to manipulate
page tables.
In my tests, on PA-RISC this patch speeds up activation 13 times.
On Opteron this patch speeds up activation by 5%.
This patch introduces a new function free_params() to free the
parameters and this uses new flags that record whether or not vmalloc()
was used and whether or not the input buffer must be wiped after use.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mike Snitzer [Fri, 21 Dec 2012 20:23:34 +0000 (20:23 +0000)]
dm block manager: reinstate message when validator fails
Reinstate a useful error message when the block manager buffer validator fails.
This was mistakenly eliminated when the block manager was converted to use
dm-bufio.
Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Jonathan Brassow [Fri, 21 Dec 2012 20:23:33 +0000 (20:23 +0000)]
dm raid: round region_size to power of two
If the user does not supply a bitmap region_size to the dm raid target,
a reasonable size is computed automatically. If this is not a power of 2,
the md code will report an error later.
This patch catches the problem early and rounds the region_size to the
next power of two.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mikulas Patocka [Fri, 21 Dec 2012 20:23:33 +0000 (20:23 +0000)]
dm snapshot: optimize track_chunk
track_chunk is always called with interrupts enabled. Consequently, we
do not need to save and restore interrupt state in "flags" variable.
This patch changes spin_lock_irqsave to spin_lock_irq and
spin_unlock_irqrestore to spin_unlock_irq.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mike Snitzer [Fri, 21 Dec 2012 20:23:32 +0000 (20:23 +0000)]
dm thin: emit ignore_discard in status when discards disabled
If "ignore_discard" is specified when creating the thin pool device then
discard support is disabled for that device. The pool device's status
should reflect this fact rather than stating "no_discard_passdown"
(which implies discards are enabled but passdown is disabled).
Reported-by: Zdenek Kabelac <zkabelac@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Joe Thornber [Fri, 21 Dec 2012 20:23:32 +0000 (20:23 +0000)]
dm persistent data: fix nested btree deletion
When deleting nested btrees, the code forgets to delete the innermost
btree. The thin-metadata code serendipitously compensates for this by
claiming there is one extra layer in the tree.
This patch corrects both problems.
Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Joe Thornber [Fri, 21 Dec 2012 20:23:31 +0000 (20:23 +0000)]
dm thin: wake worker when discard is prepared
When discards are prepared it is best to directly wake the worker that
will process them. The worker will be woken anyway, via periodic
commit, but there is no reason to not wake_worker here.
Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Joe Thornber [Fri, 21 Dec 2012 20:23:31 +0000 (20:23 +0000)]
dm thin: fix race between simultaneous io and discards to same block
There is a race when discard bios and non-discard bios are issued
simultaneously to the same block.
Discard support is expensive for all thin devices precisely because you
have to be careful to quiesce the area you're discarding. DM thin must
handle this conflicting IO pattern (simultaneous non-discard vs discard)
even though a sane application shouldn't be issuing such IO.
The race manifests as follows:
1. A non-discard bio is mapped in thin_bio_map.
This doesn't lock out parallel activity to the same block.
2. A discard bio is issued to the same block as the non-discard bio.
3. The discard bio is locked in a dm_bio_prison_cell in process_discard
to lock out parallel activity against the same block.
4. The non-discard bio's mapping continues and its all_io_entry is
incremented so the bio is accounted for in the thin pool's all_io_ds
which is a dm_deferred_set used to track time locality of non-discard IO.
5. The non-discard bio is finally locked in a dm_bio_prison_cell in
process_bio.
The race can result in deadlock, leaving the block layer hanging waiting
for completion of a discard bio that never completes, e.g.:
The thinp-test-suite's test_discard_random_sectors reliably hits this
deadlock on fast SSD storage.
The fix for this race is that the all_io_entry for a bio must be
incremented whilst the dm_bio_prison_cell is held for the bio's
associated virtual and physical blocks. That cell locking wasn't
occurring early enough in thin_bio_map. This patch fixes this.
Care is taken to always call the new function inc_all_io_entry() with
the relevant cells locked, but they are generally unlocked before
calling issue() to try to avoid holding the cells locked across
generic_submit_request.
Also, now that thin_bio_map may lock bios in a cell, process_bio() is no
longer the only thread that will do so. Because of this we must be sure
to use cell_defer_except() to release all non-holder entries, that
were added by the other thread, because they must be deferred.
This patch depends on "dm thin: replace dm_cell_release_singleton with
cell_defer_except".
Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Cc: stable@vger.kernel.org
Joe Thornber [Fri, 21 Dec 2012 20:23:31 +0000 (20:23 +0000)]
dm thin: replace dm_cell_release_singleton with cell_defer_except
Change existing users of the function dm_cell_release_singleton to share
cell_defer_except instead, and then remove the now-unused function.
Everywhere that calls dm_cell_release_singleton, the bio in question
is the holder of the cell.
If there are no non-holder entries in the cell then cell_defer_except
behaves exactly like dm_cell_release_singleton. Conversely, if there
*are* non-holder entries then dm_cell_release_singleton must not be used
because those entries would need to be deferred.
Consequently, it is safe to replace use of dm_cell_release_singleton
with cell_defer_except.
This patch is a pre-requisite for "dm thin: fix race between
simultaneous io and discards to same block".
Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mike Snitzer [Fri, 21 Dec 2012 20:23:30 +0000 (20:23 +0000)]
dm: disable WRITE SAME
WRITE SAME bios are not yet handled correctly by device-mapper so
disable their use on device-mapper devices by setting
max_write_same_sectors to zero.
As an example, a ciphertext device is incompatible because the data
gets changed according to the location at which it written and so the
dm crypt target cannot support it.
Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org Cc: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
dm ioctl: prevent unsafe change to dm_ioctl data_size
Abort dm ioctl processing if userspace changes the data_size parameter
after we validated it but before we finished copying the data buffer
from userspace.
The dm ioctl parameters are processed in the following sequence:
1. ctl_ioctl() calls copy_params();
2. copy_params() makes a first copy of the fixed-sized portion of the
userspace parameters into the local variable "tmp";
3. copy_params() then validates tmp.data_size and allocates a new
structure big enough to hold the complete data and copies the whole
userspace buffer there;
4. ctl_ioctl() reads userspace data the second time and copies the whole
buffer into the pointer "param";
5. ctl_ioctl() reads param->data_size without any validation and stores it
in the variable "input_param_size";
6. "input_param_size" is further used as the authoritative size of the
kernel buffer.
The problem is that userspace code could change the contents of user
memory between steps 2 and 4. In particular, the data_size parameter
can be changed to an invalid value after the kernel has validated it.
This lets userspace force the kernel to access invalid kernel memory.
The fix is to ensure that the size has not changed at step 4.
This patch shouldn't have a security impact because CAP_SYS_ADMIN is
required to run this code, but it should be fixed anyway.
Mikulas Patocka [Fri, 21 Dec 2012 20:23:30 +0000 (20:23 +0000)]
dm persistent data: rename node to btree_node
This patch fixes a compilation failure on sparc32 by renaming struct node.
struct node is already defined in include/linux/node.h. On sparc32, it
happens to be included through other dependencies and persistent-data
doesn't compile because of conflicting declarations.
Trond Myklebust [Fri, 21 Dec 2012 16:02:32 +0000 (11:02 -0500)]
NFS: Kill fscache warnings when mounting without -ofsc
The fscache code will currently bleat a "non-unique superblock keys"
warning even if the user is mounting without the 'fsc' option.
There should be no reason to even initialise the superblock cache cookie
unless we're planning on using fscache for something, so ensure that we
check for the NFS_OPTION_FSCACHE flag before calling into the fscache
code.
Reported-by: Paweł Sikora <pawel.sikora@agmk.net> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: David Howells <dhowells@redhat.com> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Howells [Fri, 21 Dec 2012 12:15:05 +0000 (12:15 +0000)]
NFS: Provide stub nfs_fscache_wait_on_invalidate() for when CONFIG_NFS_FSCACHE=n
Provide a stub nfs_fscache_wait_on_invalidate() function for when
CONFIG_NFS_FSCACHE=n lest the following error appear:
fs/nfs/inode.c: In function 'nfs_invalidate_mapping':
fs/nfs/inode.c:887:2: error: implicit declaration of function 'nfs_fscache_wait_on_invalidate' [-Werror=implicit-function-declaration]
cc1: some warnings being treated as errors
Linus Torvalds [Fri, 21 Dec 2012 05:30:12 +0000 (21:30 -0800)]
Merge tag 'vfio-for-v3.8-v2' of git://github.com/awilliam/linux-vfio
Pull vfio update from Alex Williamson.
* tag 'vfio-for-v3.8-v2' of git://github.com/awilliam/linux-vfio:
vfio-pci: Enable device before attempting reset
VFIO: fix out of order labels for error recovery in vfio_pci_init()
VFIO: use ACCESS_ONCE() to guard access to dev->driver
VFIO: unregister IOMMU notifier on error recovery path
vfio-pci: Re-order device reset
vfio: simplify kmalloc+copy_from_user to memdup_user
Linus Torvalds [Fri, 21 Dec 2012 04:11:52 +0000 (20:11 -0800)]
Merge branch 'for-next' of git://git.infradead.org/users/eparis/notify
Pull filesystem notification updates from Eric Paris:
"This pull mostly is about locking changes in the fsnotify system. By
switching the group lock from a spin_lock() to a mutex() we can now
hold the lock across things like iput(). This fixes a problem
involving unmounting a fs and having inodes be busy, first pointed out
by FAT, but reproducible with tmpfs.
This also restores signal driven I/O for inotify, which has been
broken since about 2.6.32."
Ugh. I *hate* the timing of this. It was rebased after the merge
window opened, and then left to sit with the pull request coming the day
before the merge window closes. That's just crap. But apparently the
patches themselves have been around for over a year, just gathering
dust, so now it's suddenly critical.
Fixed up semantic conflict in fs/notify/fdinfo.c as per Stephen
Rothwell's fixes from -next.
* 'for-next' of git://git.infradead.org/users/eparis/notify:
inotify: automatically restart syscalls
inotify: dont skip removal of watch descriptor if creation of ignored event failed
fanotify: dont merge permission events
fsnotify: make fasync generic for both inotify and fanotify
fsnotify: change locking order
fsnotify: dont put marks on temporary list when clearing marks by group
fsnotify: introduce locked versions of fsnotify_add_mark() and fsnotify_remove_mark()
fsnotify: pass group to fsnotify_destroy_mark()
fsnotify: use a mutex instead of a spinlock to protect a groups mark list
fanotify: add an extra flag to mark_remove_from_mask that indicates wheather a mark should be destroyed
fsnotify: take groups mark_lock before mark lock
fsnotify: use reference counting for groups
fsnotify: introduce fsnotify_get_group()
inotify, fanotify: replace fsnotify_put_group() with fsnotify_destroy_group()
Linus Torvalds [Fri, 21 Dec 2012 04:00:43 +0000 (20:00 -0800)]
Merge branch 'akpm' (Andrew's patch-bomb)
Merge the rest of Andrew's patches for -rc1:
"A bunch of fixes and misc missed-out-on things.
That'll do for -rc1. I still have a batch of IPC patches which still
have a possible bug report which I'm chasing down."
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (25 commits)
keys: use keyring_alloc() to create module signing keyring
keys: fix unreachable code
sendfile: allows bypassing of notifier events
SGI-XP: handle non-fatal traps
fat: fix incorrect function comment
Documentation: ABI: remove testing/sysfs-devices-node
proc: fix inconsistent lock state
linux/kernel.h: fix DIV_ROUND_CLOSEST with unsigned divisors
memcg: don't register hotcpu notifier from ->css_alloc()
checkpatch: warn on uapi #includes that #include <uapi/...
revert "rtc: recycle id when unloading a rtc driver"
mm: clean up transparent hugepage sysfs error messages
hfsplus: add error message for the case of failure of sync fs in delayed_sync_fs() method
hfsplus: rework processing of hfs_btree_write() returned error
hfsplus: rework processing errors in hfsplus_free_extents()
hfsplus: avoid crash on failed block map free
kcmp: include linux/ptrace.h
drivers/rtc/rtc-imxdi.c: must include <linux/spinlock.h>
mm: cma: WARN if freed memory is still in use
exec: do not leave bprm->interp on stack
...
Linus Torvalds [Fri, 21 Dec 2012 02:14:31 +0000 (18:14 -0800)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull VFS update from Al Viro:
"fscache fixes, ESTALE patchset, vmtruncate removal series, assorted
misc stuff."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (79 commits)
vfs: make lremovexattr retry once on ESTALE error
vfs: make removexattr retry once on ESTALE
vfs: make llistxattr retry once on ESTALE error
vfs: make listxattr retry once on ESTALE error
vfs: make lgetxattr retry once on ESTALE
vfs: make getxattr retry once on an ESTALE error
vfs: allow lsetxattr() to retry once on ESTALE errors
vfs: allow setxattr to retry once on ESTALE errors
vfs: allow utimensat() calls to retry once on an ESTALE error
vfs: fix user_statfs to retry once on ESTALE errors
vfs: make fchownat retry once on ESTALE errors
vfs: make fchmodat retry once on ESTALE errors
vfs: have chroot retry once on ESTALE error
vfs: have chdir retry lookup and call once on ESTALE error
vfs: have faccessat retry once on an ESTALE error
vfs: have do_sys_truncate retry once on an ESTALE error
vfs: fix renameat to retry on ESTALE errors
vfs: make do_unlinkat retry once on ESTALE errors
vfs: make do_rmdir retry once on ESTALE errors
vfs: add a flags argument to user_path_parent
...
Linus Torvalds [Fri, 21 Dec 2012 02:05:28 +0000 (18:05 -0800)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
Pull signal handling cleanups from Al Viro:
"sigaltstack infrastructure + conversion for x86, alpha and um,
COMPAT_SYSCALL_DEFINE infrastructure.
Note that there are several conflicts between "unify
SS_ONSTACK/SS_DISABLE definitions" and UAPI patches in mainline;
resolution is trivial - just remove definitions of SS_ONSTACK and
SS_DISABLED from arch/*/uapi/asm/signal.h; they are all identical and
include/uapi/linux/signal.h contains the unified variant."
Fixed up conflicts as per Al.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal:
alpha: switch to generic sigaltstack
new helpers: __save_altstack/__compat_save_altstack, switch x86 and um to those
generic compat_sys_sigaltstack()
introduce generic sys_sigaltstack(), switch x86 and um to it
new helper: compat_user_stack_pointer()
new helper: restore_altstack()
unify SS_ONSTACK/SS_DISABLE definitions
new helper: current_user_stack_pointer()
missing user_stack_pointer() instances
Bury the conditionals from kernel_thread/kernel_execve series
COMPAT_SYSCALL_DEFINE: infrastructure
Linus Torvalds [Fri, 21 Dec 2012 01:56:23 +0000 (17:56 -0800)]
Merge branch 'fixes' of git://git.linaro.org/people/rmk/linux-arm
Pull ARM fixes from Russell King:
"A number of smallish fixes scattered around the ARM code. Probably
the most serious one is the one from Al addressing the missing locking
in the swap emulation code."
* 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
ARM: 7607/1: realview: fix private peripheral memory base for EB rev. B boards
ARM: 7606/1: cache: flush to LoUU instead of LoUIS on uniprocessor CPUs
ARM: missing ->mmap_sem around find_vma() in swp_emulate.c
ARM: 7605/1: vmlinux.lds: Move .notes section next to the rodata
ARM: 7602/1: Pass real "__machine_arch_type" variable to setup_machine_tags() procedure
ARM: 7600/1: include CONFIG_DEBUG_LL_INCLUDE rather than mach/debug-macro.S
Linus Torvalds [Fri, 21 Dec 2012 01:55:34 +0000 (17:55 -0800)]
Merge tag 'fixes2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC fixes part 2 from Olof Johansson:
"Here are a few more fixes for 3.8. Two branches of fixes for Samsung
platforms, including fixes for the audio build errors on all non-DT
platforms. There's also a fixup to the sunxi device-tree file renames
due to a bad patch application by me, and a fix for OMAP due to
function renames merged through the powerpc tree."
* tag 'fixes2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
ARM: OMAP2+: Fix compillation error in mach-omap2/timer.c
ARM: sunxi: rename device tree source files
ARM: EXYNOS: Avoid passing the clks through platform data
ARM: S5PV210: Avoid passing the clks through platform data
ARM: S5P64X0: Add I2S clkdev support
ARM: S5PC100: Add I2S clkdev support
ARM: S3C64XX: Add I2S clkdev support
ARM: EXYNOS: Fix MSHC clocks instance names
ARM: EXYNOS: Fix NULL pointer dereference bug in SMDKV310
ARM: EXYNOS: Fix NULL pointer dereference bug in SMDK4X12
ARM: EXYNOS: Fix NULL pointer dereference bug in Origen
ARM: SAMSUNG: Add missing include guard to gpio-core.h
pinctrl: exynos5440/samsung: Staticize pcfgs
pinctrl: samsung: Fix a typo in pinctrl-samsung.h
ARM: EXYNOS: fix skip scu_enable() for EXYNOS5440
ARM: EXYNOS: fix GIC using for EXYNOS5440
ARM: EXYNOS: fix build error when MFC is not selected
Linus Torvalds [Fri, 21 Dec 2012 01:52:06 +0000 (17:52 -0800)]
Merge branch 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild misc changes from Michal Marek:
"This is the non-critical part of kbuild
- scripts/kernel-doc requires a "Return:" section for non-void
functions
- ARCH=arm SUBARCH=... support for make tags
- COMPILED_SOURCE=1 support for make tags (only indexes .c files for
which a .o exists)
- New coccinelle check
- Option parsing fix for scripts/config"
* 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
scripts/config: Fix wrong "shift" for --keep-case
scripts/tags.sh: Support compiled source
scripts/tags.sh: Support subarch for ARM
scripts/coccinelle/misc/warn.cocci: use WARN
scripts/kernel-doc: check that non-void fcts describe their return value
Kernel-doc: Convention: Use a "Return" section to describe return values
Scott Wolchok [Thu, 20 Dec 2012 23:05:52 +0000 (15:05 -0800)]
sendfile: allows bypassing of notifier events
do_sendfile() in fs/read_write.c does not call the fsnotify functions,
unlike its neighbors. This manifests as a lack of inotify ACCESS events
when a file is sent using sendfile(2).
[akpm@linux-foundation.org: use fsnotify_modify(out.file), not fsnotify_access(), per Dave] Signed-off-by: Alan Cox <alan@linux.intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Scott Wolchok <swolchok@umich.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Robin Holt [Thu, 20 Dec 2012 23:05:50 +0000 (15:05 -0800)]
SGI-XP: handle non-fatal traps
We found a user code which was raising a divide-by-zero trap. That trap
would lead to XPC connections between system-partitions being torn down
due to the die_chain notifier callouts it received.
This also revealed a different issue where multiple callers into
xpc_die_deactivate() would all attempt to do the disconnect in parallel
which would sometimes lock up but often overwhelm the console on very
large machines as each would print at least one line of output at the
end of the deactivate.
I reviewed all the users of the die_chain notifier and changed the code
to ignore the notifier callouts for reasons which will not actually lead
to a system to continue on to call die().
[akpm@linux-foundation.org: fix ia64] Signed-off-by: Robin Holt <holt@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Xiaotian Feng [Thu, 20 Dec 2012 23:05:44 +0000 (15:05 -0800)]
proc: fix inconsistent lock state
Lockdep found an inconsistent lock state when rcu is processing delayed
work in softirq. Currently, kernel is using spin_lock/spin_unlock to
protect proc_inum_ida, but proc_free_inum is called by rcu in softirq
context.
Use spin_lock_bh/spin_unlock_bh fix following lockdep warning.
=================================
[ INFO: inconsistent lock state ]
3.7.0 #36 Not tainted
---------------------------------
inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
swapper/1/0 [HC0[0]:SC1[1]:HE1:SE0] takes:
(proc_inum_lock){+.?...}, at: proc_free_inum+0x1c/0x50
{SOFTIRQ-ON-W} state was registered at:
__lock_acquire+0x8ae/0xca0
lock_acquire+0x199/0x200
_raw_spin_lock+0x41/0x50
proc_alloc_inum+0x4c/0xd0
alloc_mnt_ns+0x49/0xc0
create_mnt_ns+0x25/0x70
mnt_init+0x161/0x1c7
vfs_caches_init+0x107/0x11a
start_kernel+0x348/0x38c
x86_64_start_reservations+0x131/0x136
x86_64_start_kernel+0x103/0x112
irq event stamp: 2993422
hardirqs last enabled at (2993422): _raw_spin_unlock_irqrestore+0x55/0x80
hardirqs last disabled at (2993421): _raw_spin_lock_irqsave+0x29/0x70
softirqs last enabled at (2993394): _local_bh_enable+0x13/0x20
softirqs last disabled at (2993395): call_softirq+0x1c/0x30
other info that might help us debug this:
Possible unsafe locking scenario:
Guenter Roeck [Thu, 20 Dec 2012 23:05:42 +0000 (15:05 -0800)]
linux/kernel.h: fix DIV_ROUND_CLOSEST with unsigned divisors
Commit 263a523d18bc ("linux/kernel.h: Fix warning seen with W=1 due to
change in DIV_ROUND_CLOSEST") fixes a warning seen with W=1 due to
change in DIV_ROUND_CLOSEST.
Unfortunately, the C compiler converts divide operations with unsigned
divisors to unsigned, even if the dividend is signed and negative (for
example, -10 / 5U = 858993457). The C standard says "If one operand has
unsigned int type, the other operand is converted to unsigned int", so
the compiler is not to blame. As a result, DIV_ROUND_CLOSEST(0, 2U) and
similar operations now return bad values, since the automatic conversion
of expressions such as "0 - 2U/2" to unsigned was not taken into
account.
Fix by checking for the divisor variable type when deciding which
operation to perform. This fixes DIV_ROUND_CLOSEST(0, 2U), but still
returns bad values for negative dividends divided by unsigned divisors.
Mark the latter case as unsupported.
One observed effect of this problem is that the s2c_hwmon driver reports
a value of 4198403 instead of 0 if the ADC reads 0.
Other impact is unpredictable. Problem is seen if the divisor is an
unsigned variable or constant and the dividend is less than (divisor/2).
Tejun Heo [Thu, 20 Dec 2012 23:05:40 +0000 (15:05 -0800)]
memcg: don't register hotcpu notifier from ->css_alloc()
Commit 648bb56d076b ("cgroup: lock cgroup_mutex in cgroup_init_subsys()")
made cgroup_init_subsys() grab cgroup_mutex before invoking
->css_alloc() for the root css. Because memcg registers hotcpu notifier
from ->css_alloc() for the root css, this introduced circular locking
dependency between cgroup_mutex and cpu hotplug.
Fix it by moving hotcpu notifier registration to a subsys initcall.
======================================================
[ INFO: possible circular locking dependency detected ]
3.7.0-rc4-work+ #42 Not tainted
-------------------------------------------------------
bash/645 is trying to acquire lock:
(cgroup_mutex){+.+.+.}, at: [<ffffffff8110c5b7>] cgroup_lock+0x17/0x20
but task is already holding lock:
(cpu_hotplug.lock){+.+.+.}, at: [<ffffffff8109300f>] cpu_hotplug_begin+0x2f/0x60
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
Joe Perches [Thu, 20 Dec 2012 23:05:37 +0000 (15:05 -0800)]
checkpatch: warn on uapi #includes that #include <uapi/...
Avoid specifying internal uapi #include paths with uapi/... as
userspace should not use and never see that.
Neaten message line wrapping above.
Signed-off-by: Joe Perches <joe@perches.com> Acked-by: David Howells <dhowells@redhat.com> Acked-by: Andy Whitcroft <apw@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We already perform the ida_simple_remove() in rtc_device_release(),
which is an appropriate place. Commit 2830a6d20 ("rtc: recycle id when
unloading a rtc driver") caused the kernel to emit
ida_remove called for id=0 which is not allocated.
warnings when rtc_device_release() tries to release an alread-released
ID.
Let's restore things to their previous state and then work out why
Vincent's kernel wasn't calling rtc_device_release() - presumably a bug
in a specific sub-driver.
Reported-by: Lothar Waßmann <LW@KARO-electronics.de> Acked-by: Alexander Holler <holler@ahsoftware.de> Cc: Vincent Palatin <vpalatin@chromium.org> Cc: <stable@vger.kernel.org> [3.7.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jeremy Eder [Thu, 20 Dec 2012 23:05:32 +0000 (15:05 -0800)]
mm: clean up transparent hugepage sysfs error messages
Clarify error messages and correct a few typos in the transparent hugepage
sysfs init code.
Signed-off-by: Jeremy Eder <jeder@redhat.com> Acked-by: Rafael Aquini <aquini@redhat.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
hfsplus: rework processing of hfs_btree_write() returned error
Add to hfs_btree_write() a return of -EIO on failure of b-tree node
searching. Also add logic ofor processing errors from hfs_btree_write()
in hfsplus_system_write_inode() with a message about b-tree writing
failure.
[akpm@linux-foundation.org: reduce scope of `err', print errno on error] Signed-off-by: Vyacheslav Dubeyko <slava@dubeyko.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Hin-Tak Leung <htl10@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alan Cox [Thu, 20 Dec 2012 23:05:24 +0000 (15:05 -0800)]
hfsplus: avoid crash on failed block map free
If the read fails we kmap an error code. This doesn't end well. Instead
print a critical error and pray. This mirrors the rest of the fs
behaviour with critical error cases.
Acked-by: Vyacheslav Dubeyko <slava@dubeyko.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Vyacheslav Dubeyko <slava@dubeyko.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Cc: Jan Kara <jack@suse.cz> Acked-by: Hin-Tak Leung <htl10@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Marek Szyprowski [Thu, 20 Dec 2012 23:05:18 +0000 (15:05 -0800)]
mm: cma: WARN if freed memory is still in use
Memory returned to free_contig_range() must have no other references.
Let kernel to complain loudly if page reference count is not equal to 1.
[rientjes@google.com: support sparsemem] Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com> Acked-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kees Cook [Thu, 20 Dec 2012 23:05:16 +0000 (15:05 -0800)]
exec: do not leave bprm->interp on stack
If a series of scripts are executed, each triggering module loading via
unprintable bytes in the script header, kernel stack contents can leak
into the command line.
Normally execution of binfmt_script and binfmt_misc happens recursively.
However, when modules are enabled, and unprintable bytes exist in the
bprm->buf, execution will restart after attempting to load matching
binfmt modules. Unfortunately, the logic in binfmt_script and
binfmt_misc does not expect to get restarted. They leave bprm->interp
pointing to their local stack. This means on restart bprm->interp is
left pointing into unused stack memory which can then be copied into the
userspace argv areas.
After additional study, it seems that both recursion and restart remains
the desirable way to handle exec with scripts, misc, and modules. As
such, we need to protect the changes to interp.
This changes the logic to require allocation for any changes to the
bprm->interp. To avoid adding a new kmalloc to every exec, the default
value is left as-is. Only when passing through binfmt_script or
binfmt_misc does an allocation take place.
From SMBIOS 2.6 on, spec use little-endian encoding for UUID other than
network byte order.
So we need to get dmi version to distinguish. If version is 0.0, the
real version is taken from the SMBIOS version. This is part of original
kernel comment in code.
[akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com> Cc: Feng Jin <joe.jin@oracle.com> Cc: Jean Delvare <khali@linux-fr.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove the documentation for capability.disable. The code supporting
this parameter was removed with commit 5915eb53861c ("security: remove
dummy module")
Sonny Rao [Thu, 20 Dec 2012 23:05:07 +0000 (15:05 -0800)]
mm: fix calculation of dirtyable memory
The system uses global_dirtyable_memory() to calculate number of
dirtyable pages/pages that can be allocated to the page cache. A bug
causes an underflow thus making the page count look like a big unsigned
number. This in turn confuses the dirty writeback throttling to
aggressively write back pages as they become dirty (usually 1 page at a
time). This generally only affects systems with highmem because the
underflowed count gets subtracted from the global count of dirtyable
memory.
Minchan Kim [Thu, 20 Dec 2012 23:05:06 +0000 (15:05 -0800)]
compaction: fix build error in CMA && !COMPACTION
isolate_freepages_block() and isolate_migratepages_range() are used for
CMA as well as compaction so it breaks build for CONFIG_CMA &&
!CONFIG_COMPACTION.
This patch fixes it.
[akpm@linux-foundation.org: add "do { } while (0)", per Mel] Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
projects / karo-tx-linux.git / log