Russell King [Thu, 9 Feb 2012 01:13:41 +0000 (17:13 -0800)]
pcmcia: fix socket refcount decrementing on each resume
This fixes a memory-corrupting bug: not only does it cause the warning,
but as a result of dropping the refcount to zero, it causes the
pcmcia_socket0 device structure to be freed while it still has
references, causing slab caches corruption. A fatal oops quickly
follows this warning - often even just a 'dmesg' following the warning
causes the kernel to oops.
While testing suspend/resume on an ARM device with PCMCIA support, and a
CF card inserted, I found that after five suspend and resumes, the
kernel would complain, and shortly die after with slab corruption.
WARNING: at include/linux/kref.h:41 kobject_get+0x28/0x50()
As the message doesn't give a clue about which kobject, and the built-in
debugging in drivers/base/power/main.c happens too late, this was added
right before each get_device():
+ /* now, add the new card */
+ pcmcia_bus_add(skt);
+ return 0;
+}
As can be seen, the original function called pcmcia_get_socket() and
pcmcia_put_socket() around the guts, whereas the replacement code
calls pcmcia_put_socket() only in one path. This creates an imbalance
in the refcounting.
Testing with pcmcia_put_socket() put removed shows that the bug is gone:
Tested-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hugh Dickins [Thu, 9 Feb 2012 01:13:40 +0000 (17:13 -0800)]
mm: fix UP THP spin_is_locked BUGs
Fix CONFIG_TRANSPARENT_HUGEPAGE=y CONFIG_SMP=n CONFIG_DEBUG_VM=y
CONFIG_DEBUG_SPINLOCK=n kernel: spin_is_locked() is then always false,
and so triggers some BUGs in Transparent HugePage codepaths.
asm-generic/bug.h mentions this problem, and provides a WARN_ON_SMP(x);
but being too lazy to add VM_BUG_ON_SMP, BUG_ON_SMP, WARN_ON_SMP_ONCE,
VM_WARN_ON_SMP_ONCE, just test NR_CPUS != 1 in the existing VM_BUG_ONs.
Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In current code, pltfm->als_vmin is set to LM3530_ALS_WINDOW_mV and
pltfm->als_vmax is 0. This does not make sense. I think what we want
here is setting pltfm->als_vmax to LM3530_ALS_WINDOW_mV.
Both als_vmin and als_vmax local variables will be set to
pltfm->als_vmin and pltfm->als_vmax by a few lines latter. Thus also
remove a redundant assignment for als_vmin and als_vmax in this patch.
Signed-off-by: Axel Lin <axel.lin@gmail.com> Cc: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com> Acked-by: Milo(Woogyom) Kim <milo.kim@ti.com> Tested-by: Milo(Woogyom) Kim <milo.kim@ti.com> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Thu, 9 Feb 2012 01:13:38 +0000 (17:13 -0800)]
mm: compaction: check for overlapping nodes during isolation for migration
When isolating pages for migration, migration starts at the start of a
zone while the free scanner starts at the end of the zone. Migration
avoids entering a new zone by never going beyond the free scanned.
Unfortunately, in very rare cases nodes can overlap. When this happens,
migration isolates pages without the LRU lock held, corrupting lists
which will trigger errors in reclaim or during page free such as in the
following oops
The "X" in the taint flag means that external modules were loaded but but
is unrelated to the bug triggering. The real problem was because the PFN
layout looks like this
The fix is straight-forward. isolate_migratepages() has to make a
similar check to isolate_freepage to ensure that it never isolates pages
from a zone it does not hold the LRU lock for.
This was discovered in a 3.0-based kernel but it affects 3.1.x, 3.2.x
and current mainline.
Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Michal Nazarewicz <mina86@mina86.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Wed, 8 Feb 2012 22:56:39 +0000 (14:56 -0800)]
Merge tag 'sound-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
sound fixes #2 for 3.3-rc3
A collection of small fixes, mostly for regressions.
In addition, a few ASoC wm8994 updates are included, too.
* tag 'sound-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ASoC: wm8994: Disable line output discharge prior to ramping VMID
ASoC: wm8994: Fix typo in VMID ramp setting
ALSA: oxygen, virtuoso: fix exchanged L/R volumes of aux and CD inputs
ALSA: usb-audio: add Edirol UM-3G support
ALSA: hda - add support for Uniwill ECS M31EI notebook
ALSA: hda - Fix error handling in patch_ca0132.c
ASoC: wm8994: Enabling VMID should take a runtime PM reference
ALSA: hda/realtek - Fix a wrong condition
ALSA: emu8000: Remove duplicate linux/moduleparam.h include from emu8000_patch.c
ALSA: hda/realtek - Add missing Bass and CLFE as vmaster slaves
ASoC: wm_hubs: Correct line input to line output 2 paths
ASoC: cs42l73: Fix Output [X|A|V]SP_SCLK Sourcing Mode setting for master mode
ASoC: wm8962: Fix word length configuration
ASoC: core: Better support for idle_bias_off suspend ignores
ASoC: wm8994: Remove ASoC level register cache sync
ASoC: wm_hubs: Fix routing of input PGAs to line output mixer
Takashi Iwai [Wed, 8 Feb 2012 20:29:38 +0000 (21:29 +0100)]
Merge tag 'asoc-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
A few small WM8994 updates to go on top of the previous lot of things
that were sent. They collide with some -next work so I'd really like to
get them into 3.3-rc3 if possible to merge back up into the -next code.
All driver specific and unexciting in the grand scheme of things.
Clemens Ladisch [Sat, 4 Feb 2012 19:56:47 +0000 (20:56 +0100)]
ALSA: oxygen, virtuoso: fix exchanged L/R volumes of aux and CD inputs
The driver accidentally exchanged the left/right fields for stereo AC'97
mixer registers. This affected only the aux and CD inputs because the
line input bypasses the AC'97 codec and the mic input is mono; cards
without AC'97 (Xonar DS/DG/HDAV Slim, HG2PCI, HiFier) were not affected.
Reported-and-tested-by: Abby Cedar <abbycedar@yahoo.com.au> Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Cc: 2.6.31+ <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
Linus Torvalds [Tue, 7 Feb 2012 23:54:02 +0000 (15:54 -0800)]
Merge tag 'fbdev-fixes-for-3.3-1' of git://github.com/schandinat/linux-2.6
fbdev fixes for 3.3
It includes:
- compile fix for fsl-diu-fb
- fix for a suspend/resume issue in atmel_lcdfb
- fix for a suspend/resume issue in OMAP
- workaround for a hardware bug to avoid physical damage in OMAP
- really trivial dead code removal in intelfb
* tag 'fbdev-fixes-for-3.3-1' of git://github.com/schandinat/linux-2.6:
atmel_lcdfb: fix usage of CONTRAST_CTR in suspend/resume
intelfb: remove some dead code
drivers/video: compile fixes for fsl-diu-fb.c
OMAPDSS: HDMI: PHY burnout fix
OMAP: 4430SDP/Panda: add HDMI HPD gpio
OMAP: 4430SDP/Panda: setup HDMI GPIO muxes
OMAPDSS: remove wrong HDMI HPD muxing
OMAP: 4430SDP/Panda: rename HPD GPIO to CT_CP_HPD
OMAP: 4430SDP/Panda: use gpio_free_array to free HDMI gpios
OMAPDSS: use sync versions of pm_runtime_put
Linus Torvalds [Tue, 7 Feb 2012 22:35:19 +0000 (14:35 -0800)]
Merge tag 'ib-srpt-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband
Cleanups and error path fixes for the new SRP (SCSI RDMA protocol) target.
* tag 'ib-srpt-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband:
IB/srpt: Don't return freed pointer from srpt_alloc_ioctx_ring()
IB/srpt: Fix ERR_PTR() vs. NULL checking confusion
IB/srpt: Remove unneeded <linux/version.h> include
IB/srpt: Use ARRAY_SIZE() instead of open-coding
IB/srpt: Use DEFINE_SPINLOCK()/LIST_HEAD()
Linus Torvalds [Tue, 7 Feb 2012 22:32:24 +0000 (14:32 -0800)]
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
arch: fix ioport mapping on mips,sh
Kevin Cernekee reported that recent cleanup that replaced pci_iomap with
a generic function failed to take into account the differences in io
port handling on mips and sh architectures.
Rather than revert the changes reintroducing the code duplication, this
patchset fixes this by adding ability for architectures to override
ioport mapping for pci devices.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
sh: use the the PCI channels's io_map_base
mips: use the the PCI controller's io_map_base
lib: add NO_GENERIC_PCI_IOPORT_MAP
Linus Torvalds [Tue, 7 Feb 2012 22:07:20 +0000 (14:07 -0800)]
Merge git://git.samba.org/sfrench/cifs-2.6
* git://git.samba.org/sfrench/cifs-2.6:
cifs: Fix oops in session setup code for null user mounts
[CIFS] Update cifs Kconfig title to match removal of experimental dependency
cifs: fix printk format warnings
cifs: check offset in decode_ntlmssp_challenge()
cifs: NULL dereference on allocation failure
Linus Torvalds [Tue, 7 Feb 2012 22:05:49 +0000 (14:05 -0800)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/mfd-2.6
* '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
Takashi Iwai [Tue, 7 Feb 2012 10:00:53 +0000 (11:00 +0100)]
ALSA: hda - Fix error handling in patch_ca0132.c
In patch_ca0132.c, the error returned from chipio_write() isn't checked
always. Also, the power-up/down sequence isn't tracked properly in some
error paths.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
Takashi Iwai [Tue, 7 Feb 2012 10:04:48 +0000 (11:04 +0100)]
Merge tag 'asoc-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
The only particularly remarkable change here is the one for handling of
the Android suspend ignore code for idle_bias_off CODECs. That one is
actually a regression fix as some of the new power savings that have
been introduced confused the suspend ignore code, making devices that
are active for non-audio reasons look like they are idle causing them to
be suspended instead of being kept active.
Linus Torvalds [Tue, 7 Feb 2012 00:26:58 +0000 (16:26 -0800)]
Merge branch 'kvm-updates/3.3' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Fixing a regression with the PMU MSRs when PMU virtualization is
disabled, a guest-internal DoS with the SYSCALL instruction, and a dirty
memory logging race that may cause live migration to fail.
* 'kvm-updates/3.3' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: do not #GP on perf MSR writes when vPMU is disabled
KVM: x86: fix missing checks in syscall emulation
KVM: x86: extend "struct x86_emulate_ops" with "get_cpuid"
KVM: Fix __set_bit() race in mark_page_dirty() during dirty logging
Linus Torvalds [Mon, 6 Feb 2012 23:29:56 +0000 (15:29 -0800)]
Merge tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux-2.6
GPIO fixes for v3.3-rc2
Straight forward bug fixes in this branch. A couple of x86 gpio drivers
missing spinlock initialization, an API change fixup for the samsung driver
and a name typo fix.
* tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux-2.6:
gpio: Add missing spin_lock_init in gpio-ml-ioh driver
gpio: Add missing spin_lock_init in gpio-pch driver
gpio: samsung: adapt to changes in gpio specifier translator function declaration
Correct bad gpio naming
Linus Torvalds [Mon, 6 Feb 2012 23:25:48 +0000 (15:25 -0800)]
Merge tag 'hwmon-fixes-for-3.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging
One patch to fix fan detection on NCT6776F.
* tag 'hwmon-fixes-for-3.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
hwmon: (w83627ehf) Fix number of fans for NCT6776F
Heiko Carstens [Sat, 4 Feb 2012 09:47:10 +0000 (10:47 +0100)]
exec: fix use-after-free bug in setup_new_exec()
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.
Przemo Firszt [Sun, 5 Feb 2012 22:35:24 +0000 (22:35 +0000)]
HID: wacom: Fix invalid power_supply_powers calls
power_supply_powers calls added in 35b4c01e2 ("power_supply: add "powers" links
to self-powered HID devices") have to be called after power device is created.
This patch also fixes the second call - it has to be "ac" instead of "battery"
Jiri Kosina [Mon, 6 Feb 2012 15:11:09 +0000 (16:11 +0100)]
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into upstream-fixes
Sync with Linus' tree. This is necessary to have a base for
patch that fixes commit 35b4c01e29b ("power_supply: add "powers"
links to self-powered HID devices") which went in through Anton's
tree.
Takashi Iwai [Mon, 6 Feb 2012 09:24:04 +0000 (10:24 +0100)]
ALSA: hda/realtek - Fix a wrong condition
sparse complains that "spec->multiout.dac_nids" is a pointer.
sound/pci/hda/patch_realtek.c:2321:37: error: incompatible types for operation (>)
sound/pci/hda/patch_realtek.c:2321:37: left side has type unsigned short const [usertype] *dac_nids
sound/pci/hda/patch_realtek.c:2321:37: right side has type int
It was meant to be num_dacs instead of dac_nids.
Although the current code still works as expected (when num_dacs is zero,
dac_nids should be NULL, too), better to fix now, of course.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: David Henningsson <david.henningsson@canonical.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
Guenter Roeck [Fri, 27 Jan 2012 13:43:59 +0000 (05:43 -0800)]
hwmon: (w83627ehf) Fix number of fans for NCT6776F
NCT6776F can select fan input pins for fans 3 to 5 with a secondary set of
chip register bits. Check that second set of bits in addition to the first set
to detect if fans 3..5 are monitored.
Linus Torvalds [Sat, 4 Feb 2012 23:21:39 +0000 (15:21 -0800)]
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
PM / Freezer: Thaw only kernel threads if freezing of kernel threads fails
If freezing of kernel threads fails, we are expected to automatically
thaw tasks in the error recovery path. However, at times, we encounter
situations in which we would like the automatic error recovery path
to thaw only the kernel threads, because we want to be able to do
some more cleanup before we thaw userspace. Something like:
error = freeze_kernel_threads();
if (error) {
/* Do some cleanup */
/* Only then thaw userspace tasks*/
thaw_processes();
}
An example of such a situation is where we freeze/thaw filesystems
during suspend/hibernation. There, if freezing of kernel threads
fails, we would like to thaw the frozen filesystems before thawing
the userspace tasks.
So, modify freeze_kernel_threads() to thaw only kernel threads in
case of freezing failure. And change suspend_freeze_processes()
accordingly. (At the same time, let us also get rid of the rather
cryptic usage of the conditional operator (:?) in that function.)
[rjw: In fact, this patch fixes a regression introduced during the
3.3 merge window, because without it thaw_processes() may be called
before swsusp_free() in some situations and that may lead to massive
memory allocation failures.]
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Nigel Cunningham <nigel@tuxonice.net> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Linus Torvalds [Sat, 4 Feb 2012 20:11:40 +0000 (12:11 -0800)]
Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
arm-soc fixes for 3.3-rc
* A series of OMAP regression fixes for merge window fallout
* Two patches for Davinci, one removes some misdefined clocks, the other
is a regression fix for merge window fallout
* Two patches that makes Broadcom bcmring build again (and removes a
bunch of unused code in the process)
breaks building of this platform, since what used to be the
last field of the MACHINE_START/END block didn't have a
trailing comma. Once another field was added below, we get:
arch/arm/mach-bcmring/arch.c:198: error: request for member 'restart' in something not a structure or union
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Acked-by: Jiandong Zheng <jdzheng@broadcom.com> Signed-off-by: Olof Johansson <olof@lixom.net>
Linus Torvalds [Sat, 4 Feb 2012 18:54:26 +0000 (10:54 -0800)]
Merge branch 'fixes' of git://git.infradead.org/users/vkoul/slave-dma
* '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
Linus Torvalds [Sat, 4 Feb 2012 15:17:47 +0000 (07:17 -0800)]
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
Nicolas Ferre <nicolas.ferre@atmel.com> alco confirmed:
"After double checking with designers, I must admit that I misunderstood
the way of optimizing accesses to SMC. 16 bit nand is not so common
those days..."
Reported-by: Nikolaus Voss <n.voss@weinmann.de> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Cc: stable@kernel.org [3.1+]
Mel Gorman [Fri, 3 Feb 2012 23:37:18 +0000 (15:37 -0800)]
mm: compaction: check pfn_valid when entering a new MAX_ORDER_NR_PAGES block during isolation for migration
When isolating for migration, migration starts at the start of a zone
which is not necessarily pageblock aligned. Further, it stops isolating
when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally
not aligned. This allows isolate_migratepages() to call pfn_to_page() on
an invalid PFN which can result in a crash. This was originally reported
against a 3.0-based kernel with the following trace in a crash dump.
The migrate_pfn is just below a memory hole and the free scanner is beyond
the hole. When isolate_migratepages started, it scans from migrate_pfn to
migrate_pfn+pageblock_nr_pages which is now in a memory hole. It checks
pfn_valid() on the first PFN but then scans into the hole where there are
not necessarily valid struct pages.
This patch ensures that isolate_migratepages calls pfn_valid when
necessary.
Reported-by: Herbert van den Bergh <herbert.van.den.bergh@oracle.com> Tested-by: Herbert van den Bergh <herbert.van.den.bergh@oracle.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Michal Nazarewicz <mina86@mina86.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Shaohua Li [Fri, 3 Feb 2012 23:37:17 +0000 (15:37 -0800)]
readahead: fix pipeline break caused by block plug
Herbert Poetzl reported a performance regression since 2.6.39. The test
is a simple dd read, but with big block size. The reason is:
T1: ra (A, A+128k), (A+128k, A+256k)
T2: lock_page for page A, submit the 256k
T3: hit page A+128K, ra (A+256k, A+384). the range isn't submitted
because of plug and there isn't any lock_page till we hit page A+256k
because all pages from A to A+256k is in memory
T4: hit page A+256k, ra (A+384, A+ 512). Because of plug, the range isn't
submitted again.
T5: lock_page A+256k, so (A+256k, A+512k) will be submitted. The task is
waitting for (A+256k, A+512k) finish.
There is no request to disk in T3 and T4, so readahead pipeline breaks.
We really don't need block plug for generic_file_aio_read() for buffered
I/O. The readahead already has plug and has fine grained control when I/O
should be submitted. Deleting plug for buffered I/O fixes the regression.
One side effect is plug makes the request size 256k, the size is 128k
without it. This is because default ra size is 128k and not a reason we
need plug here.
Vivek said:
: We submit some readahead IO to device request queue but because of nested
: plug, queue never gets unplugged. When read logic reaches a page which is
: not in page cache, it waits for page to be read from the disk
: (lock_page_killable()) and that time we flush the plug list.
:
: So effectively read ahead logic is kind of broken in parts because of
: nested plugging. Removing top level plug (generic_file_aio_read()) for
: buffered reads, will allow unplugging queue earlier for readahead.
Signed-off-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Reported-by: Herbert Poetzl <herbert@13thfloor.at> Tested-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jiang Liu [Fri, 3 Feb 2012 23:37:16 +0000 (15:37 -0800)]
kprobes: fix a memory leak in function pre_handler_kretprobe()
In function pre_handler_kretprobe(), the allocated kretprobe_instance
object will get leaked if the entry_handler callback returns non-zero.
This may cause all the preallocated kretprobe_instance objects exhausted.
This issue can be reproduced by changing
samples/kprobes/kretprobe_example.c to probe "mutex_unlock". And the fix
is straightforward: just put the allocated kretprobe_instance object back
onto the free_instances list.
[akpm@linux-foundation.org: use raw_spin_lock/unlock] Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Acked-by: Jim Keniston <jkenisto@us.ibm.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Carsten Otte [Fri, 3 Feb 2012 23:37:14 +0000 (15:37 -0800)]
mm/filemap_xip.c: fix race condition in xip_file_fault()
Fix a race condition that shows in conjunction with xip_file_fault() when
two threads of the same user process fault on the same memory page.
In this case, the race winner will install the page table entry and the
unlucky loser will cause an oops: xip_file_fault calls vm_insert_pfn (via
vm_insert_mixed) which drops out at this check:
retval = -EBUSY;
if (!pte_none(*pte))
goto out_unlock;
The resulting -EBUSY return value will trigger a BUG_ON() in
xip_file_fault.
This fix simply considers the fault as fixed in this case, because the
race winner has successfully installed the pte.
[akpm@linux-foundation.org: use conventional (and consistent) comment layout] Reported-by: David Sadler <dsadler@us.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Reported-by: Louis Alex Eisner <leisner@cs.ucsd.edu> Cc: Hugh Dickins <hughd@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fabio Baltieri [Fri, 3 Feb 2012 23:37:14 +0000 (15:37 -0800)]
avr32: select generic atomic64_t support
Enable use of the generic atomic64 implementation on AVR32 platforms.
Without this the kernel fails to build as the architecture does not
provide its version.
Postpone resetting page->mapping until the final remove_migration_ptes().
Otherwise the expression PageAnon(migration_entry_to_page(entry)) does not
work.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Hugh Dickins <hughd@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Akinobu Mita [Fri, 3 Feb 2012 23:37:13 +0000 (15:37 -0800)]
xtensa: fix memscan()
Defining memscan() as memchr() is wrong, because the return values of
memscan() and memchr() are different when the character is not found. So
use the generic memscan() implementation to fix this.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Chris Zankel <chris@zankel.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Fri, 3 Feb 2012 20:41:31 +0000 (12:41 -0800)]
Merge tag 'kmemleak-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux
Trivial kmemleak bug-fixes:
- Early logging doesn't stop when kmemleak is off by default.
- Zero-size scanning areas should be ignored (currently it prints a
warning).
* tag 'kmemleak-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux:
kmemleak: Disable early logging when kmemleak is off by default
kmemleak: Only scan non-zero-size areas
Linus Torvalds [Fri, 3 Feb 2012 18:06:15 +0000 (10:06 -0800)]
Merge tag 'sound-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
sound fixes for 3.3-rc3
Most of commits are either regression fixes for varioud HD-audio
codecs or small ASoC fixes. Also a trivial build fix is included.
* tag 'sound-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: hda - Disable dynamic-power control for VIA as default
ALSA: hda - Allow analog low-current mode when dynamic power-control is on
ALSA: hda - Fix the logic to detect VIA analog low-current mode
ALSA: hda - Check power-state before changing in patch_via.c
ALSA: HDA: Fix duplicated output to more than one codec
ALSA: hda - Fix calling cs_automic twice for Cirrus codecs.
ALSA: HDA: Remove quirk for Toshiba Qosmio G50
ALSA: HDA: Fix jack creation for codecs with front and rear Line In
ALSA: hda - Apply 0x0f-VREF fix to all ASUS laptops with ALC861/660
ASoC: neo1973_wm8753: remove references to the neo1973-gta01 machine
ALSA: Add #ifdef CONFIG_PCI guard for snd_pci_quirk_* functions
ASoC: wm_hubs: fix wrong bits for LINEOUT2 N/P mixer
ALSA: HDA: Remove quirk for Asus N53Jq
ASoC: wm_hubs: Enable line out VMID buffer for single ended line outputs
ASoC: wm5100: Mark register cache as dirty when regulators are disabled
ASoC: wm8962: Mark register cache as dirty when regulators are disabled
ASoC: wm8996: Mark register cache as dirty when regulators are disabled
ASoC: wm5100: Fix microphone configuration
ASoC: wm5100: Make sure we switch to button reporting mode
Peter Ujfalusi [Sat, 14 Jan 2012 19:58:44 +0000 (20:58 +0100)]
mfd: Avoid twl6040-codec PLL reconfiguration when not needed
Do not reconfigure the PLL in case it has been configured already
with the requested parameters.
In case of different PLL configuration do only the needed changes.
This can save considerable amount of time since we can avoid the
defined protocol (with delays) for the PLL configuration.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Will Deacon [Fri, 3 Feb 2012 10:08:05 +0000 (11:08 +0100)]
ARM: 7314/1: kuser: consistently use usr_ret for returning from helpers
__kuser_cmpxchg64 has a return path using bx lr to get back to the caller.
This is actually ok since the code in question is predicated on
CONFIG_CPU_32v6K, but for the sake of consistency using the usr_ret
macro is probably better.
Acked-by: Dave Martin <dave.martin@linaro.org> Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Linus Torvalds [Thu, 2 Feb 2012 23:47:33 +0000 (15:47 -0800)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
rbd: fix safety of rbd_put_client()
rbd: fix a memory leak in rbd_get_client()
ceph: create a new session lock to avoid lock inversion
ceph: fix length validation in parse_reply_info()
ceph: initialize client debugfs outside of monc->mutex
ceph: change "ceph.layout" xattr to be "ceph.file.layout"
cifs: Fix oops in session setup code for null user mounts
For null user mounts, do not invoke string length function
during session setup.
Cc: <stable@kernel.org Reported-and-Tested-by: Chris Clayton <chris2553@googlemail.com> Acked-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com> Signed-off-by: Steve French <smfrench@gmail.com>
Alex Elder [Sun, 29 Jan 2012 19:57:43 +0000 (13:57 -0600)]
rbd: fix safety of rbd_put_client()
The rbd_client structure uses a kref to arrange for cleaning up and
freeing an instance when its last reference is dropped. The cleanup
routine is rbd_client_release(), and one of the things it does is
delete the rbd_client from rbd_client_list. It acquires node_lock
to do so, but the way it is done is still not safe.
The problem is that when attempting to reuse an existing rbd_client,
the structure found might already be in the process of getting
destroyed and cleaned up.
Here's the scenario, with "CLIENT" representing an existing
rbd_client that's involved in the race:
Thread on CPU A | Thread on CPU B
--------------- | ---------------
rbd_put_client(CLIENT) | rbd_get_client()
kref_put() | (acquires node_lock)
kref->refcount becomes 0 | __rbd_client_find() returns CLIENT
calls rbd_client_release() | kref_get(&CLIENT->kref);
| (releases node_lock)
(acquires node_lock) |
deletes CLIENT from list | ...and starts using CLIENT...
(releases node_lock) |
and frees CLIENT | <-- but CLIENT gets freed here
Fix this by having rbd_put_client() acquire node_lock. The result
could still be improved, but at least it avoids this problem.
Signed-off-by: Alex Elder <elder@dreamhost.com> Signed-off-by: Sage Weil <sage@newdream.net>
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>
Alex Elder [Fri, 13 Jan 2012 01:48:10 +0000 (17:48 -0800)]
ceph: create a new session lock to avoid lock inversion
Lockdep was reporting a possible circular lock dependency in
dentry_lease_is_valid(). That function needs to sample the
session's s_cap_gen and and s_cap_ttl fields coherently, but needs
to do so while holding a dentry lock. The s_cap_lock field was
being used to protect the two fields, but that can't be taken while
holding a lock on a dentry within the session.
In most cases, the s_cap_gen and s_cap_ttl fields only get operated
on separately. But in three cases they need to be updated together.
Implement a new lock to protect the spots updating both fields
atomically is required.
Signed-off-by: Alex Elder <elder@dreamhost.com> Reviewed-by: Sage Weil <sage@newdream.net>
Xi Wang [Sun, 15 Jan 2012 03:20:59 +0000 (22:20 -0500)]
ceph: fix length validation in parse_reply_info()
"len" is read from network and thus needs validation. Otherwise, given
a bogus "len" value, p+len could be an out-of-bounds pointer, which is
used in further parsing.
Signed-off-by: Xi Wang <xi.wang@gmail.com> Signed-off-by: Sage Weil <sage@newdream.net>
Sage Weil [Sat, 14 Jan 2012 06:22:03 +0000 (22:22 -0800)]
ceph: initialize client debugfs outside of monc->mutex
Initializing debufs under monc->mutex introduces a lock dependency for
sb->s_type->i_mutex_key, which (combined with several other dependencies)
leads to an annoying lockdep warning. There's no particular reason to do
the debugfs setup under this lock, so move it out.
It used to be the case that our first monmap could come from the OSD; that
is no longer the case with recent servers, so we will reliably set up the
client entry during the initial authentication.
We don't have to worry about racing with debugfs teardown by
ceph_debugfs_client_cleanup() because ceph_destroy_client() calls
ceph_msgr_flush() first, which will wait for the message dispatch work
to complete (and the debugfs init to complete).
Fixes: #1940 Signed-off-by: Sage Weil <sage@newdream.net>
Alex Elder [Thu, 12 Jan 2012 01:41:01 +0000 (17:41 -0800)]
ceph: change "ceph.layout" xattr to be "ceph.file.layout"
The virtual extended attribute named "ceph.layout" is meaningful
only for regular files. Change its name to be "ceph.file.layout" to
more directly reflect that in the ceph xattr namespace. Preserve
the old "ceph.layout" name for the time being (until we decide it's
safe to get rid of it entirely).
Add a missing initializer for "readonly" in the terminating entry.
Signed-off-by: Alex Elder <elder@dreamhost.com> Reviewed-by: Sage Weil <sage@newdream.net>
Linus Torvalds [Thu, 2 Feb 2012 19:19:03 +0000 (11:19 -0800)]
Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
drm/radeon/kms/blit: fix blit copy for very large buffers
drm/radeon/kms: fix TRAVIS panel setup
drm/radeon: fix use after free in ATRM bios reading code.
drm/radeon/kms: Fix device tree linkage of DP i2c buses too
drm/radeon: Set DESKTOP_HEIGHT register to the framebuffer (not mode) height.
drm/radeon/kms: disable output polling when suspended
drm/nv50/pm: signedness bug in nv50_pm_clocks_pre()
drm/nouveau/gem: fix fence_sync race / oops
drm/nouveau: fix typo on mxmdcb option
drm/nouveau/mxm: pretend to succeed, even if we can't shadow the MXM-SIS
drm/nouveau/disp: check that panel power gpio is enabled at init time
Linus Torvalds [Thu, 2 Feb 2012 19:11:13 +0000 (11:11 -0800)]
Merge branches 'core-urgent-for-linus', 'perf-urgent-for-linus', 'sched-urgent-for-linus' and 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* '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
Catalin Marinas [Wed, 25 Jan 2012 10:54:22 +0000 (11:54 +0100)]
ARM: 7302/1: Add TLB flushing for both entries in a PMD
Linux uses two PMD entries for a PTE with the classic page table format,
covering 2MB range. However, the __pte_free_tlb() function only adds a
single TLB flush corresponding to 1MB range covering 'addr'. On
Cortex-A15, level 1 entries can be cached by the TLB independently of
the level 2 entries and without additional flushing a PMD entry would be
left pointing at the wrong PTE. The patch limits the TLB flushing range
to two 4KB pages around the 1MB boundary within PMD.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Will Deacon [Wed, 25 Jan 2012 18:36:28 +0000 (19:36 +0100)]
ARM: 7303/1: perf: add empty NODE event definitions for Cortex-A5 and Cortex-A15
Commit 89d6c0b5 ("perf, arch: Add generic NODE cache events") added
empty NODE event definitions for the ARM PMU implementations. This was
merged along with Cortex-A5 and Cortex-A15 PMU support, so they missed
out on the original patch.
This patch adds the empty definitions to Cortex-A5 and Cortex-A15.
Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Will Deacon [Mon, 30 Jan 2012 19:23:29 +0000 (20:23 +0100)]
ARM: 7308/1: vfp: flush thread hwstate before copying ptrace registers
If we are context switched whilst copying into a thread's
vfp_hard_struct then the partial copy may be corrupted by the VFP
context switching code (see "ARM: vfp: flush thread hwstate before
restoring context from sigframe").
This patch updates the ptrace VFP set code so that the thread state is
flushed before the copy, therefore disabling VFP and preventing
corruption from occurring.
Cc: stable <stable@vger.kernel.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
In a preemptible kernel, vfp_set() can be preempted, causing the
hardware VFP context to be switched while the thread vfp state is
being read and modified. This leads to a race condition which can
cause the thread vfp state to become corrupted if lazy VFP context
save occurs due to preemption in between the time thread->vfpstate
is read and the time the modified state is written back.
This may occur if preemption occurs during the execution of a
ptrace() call which modifies the VFP register state of a thread.
Such instances should be very rare in most realistic scenarios --
none has been reported, so far as I am aware. Only uniprocessor
systems should be affected, since VFP context save is not currently
lazy in SMP kernels.
The problem was introduced by my earlier patch migrating to use
regsets to implement ptrace.
This patch does a vfp_sync_hwstate() before reading
thread->vfpstate, to make sure that the thread's VFP state is not
live in the hardware registers while the registers are modified.
Thanks to Will Deacon for spotting this.
Cc: stable <stable@vger.kernel.org> Signed-off-by: Dave Martin <dave.martin@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Will Deacon [Mon, 30 Jan 2012 19:21:42 +0000 (20:21 +0100)]
ARM: 7306/1: vfp: flush thread hwstate before restoring context from sigframe
Following execution of a signal handler, we currently restore the VFP
context from the ucontext in the signal frame. This involves copying
from the user stack into the current thread's vfp_hard_struct and then
flushing the new data out to the hardware registers.
This is problematic when using a preemptible kernel because we could be
context switched whilst updating the vfp_hard_struct. If the current
thread has made use of VFP since the last context switch, the VFP
notifier will copy from the hardware registers into the vfp_hard_struct,
overwriting any data that had been partially copied by the signal code.
Disabling preemption across copy_from_user calls is a terrible idea, so
instead we move the VFP thread flush *before* we update the
vfp_hard_struct. Since the flushing is performed lazily, this has the
effect of disabling VFP and clearing the CPU's VFP state pointer,
therefore preventing the thread from being updated with stale data on
the next context switch.
Cc: stable <stable@vger.kernel.org> Tested-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Joachim Eastwood reports:
| "ARM: 7304/1: ioremap: fix boundary check when reusing static mapping"
| Commit: 3c424f359898aff48c3d5bed608ac706f8a528c3 in Linus master
|
| Breaks booting on my custom AT91RM9200 board.
| There isn't any error messages or anything that indicates what goes
| wrong it just stops after; Uncompressing Linux... done, booting the
| kernel.
|
| Reverting it makes my board boot again.
Clearly, an area for pfn 0x200, 16K can't ever satisfy a request for pfn
0xfffff. This happens because the changed if statement becomes:
if (0x00200 > 0xfffff ||
0xfffff000 + 0x400 + 0x1000-1 > 0x00200000 + 0x4000-1)
and therefore:
if (0x00200 > 0xfffff ||
0x000003ff > 0x00203fff)
The if condition fails, and so we _believe_ that the SRAM mapping fits
our request. Clearly that's totally bogus.
Moreover, the original premise of the 'fix' patch was wrong:
| The condition checking boundaries of the requested and existing
| mappings didn't take in-page offset into consideration though,
| which lead to obscure and hard to debug problems when requested
| mapping crossed end of the static one.
as the code immediately above this loop does:
size = PAGE_ALIGN(offset + size);
so 'size' already contains the requested offset into the page.
Ilija Hadzic [Thu, 2 Feb 2012 15:26:24 +0000 (10:26 -0500)]
drm/radeon/kms/blit: fix blit copy for very large buffers
Evergreen and NI blit copy was broken if the buffer maps to a rectangle
whose one dimension is 16384 (max dimension allowed by these chips).
In the mainline kernel, the problem is exposed only when buffers are
very large (1G), but it's still a problem. The problem could be exposed
for smaller buffers if anyone modifies the algorithm for rectangle
construction in r600_blit_create_rect() (the reason why someone would
modify that algorithm is to tune the performance of buffer moves).
The root cause was in i2f() function which only operated on range between
0 and 16383. Fix this by extending the range of i2f() function to 0 to
32767.
While at it improve the function so that the range can be easily
extended in the future (if it becomes necessary), cleanup lines
over 80 characters, and replace in-line comments with one strategic
comment that explains the crux of the function.
Credits to michel@daenzer.net for pointing out the root cause of
the bug.
v2: Fix I2F_MAX_INPUT constant definition goof and warn only once
if input argument is out of range. Edit the comment a little
bit to avoid some linguistic confusion and make it look better
in general.
Signed-off-by: Ilija Hadzic <ihadzic@research.bell-labs.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Reviewed-by: Michel Dänzer <michel@daenzer.net> Signed-off-by: Dave Airlie <airlied@redhat.com>
Takashi Iwai [Wed, 1 Feb 2012 09:33:23 +0000 (10:33 +0100)]
ALSA: hda - Allow analog low-current mode when dynamic power-control is on
VIA codecs have several different power-saving features, and one of
them is the analog low-current mode. But it turned out that the ALC
mode causes pop-noises at each on/off time on some machines. As a
quick workaround, disable the ALC when another power-saving feature,
the dynamic pin power-control, is turned off, too, since the dynamic
power-control is already exposed as a mixer enum element so that user
can turn it on/off freely.
projects / linux-beck.git / log