Check the result of sscanf to verify a result was found.
report and error and abort if pattern was not found.
Signed-off-by: Joshua Clayton <stillcompiling@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
For testing of larger data transfers, output unmodified data
directly to a file.
Signed-off-by: Joshua Clayton <stillcompiling@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add input file support to facilitate testing larger data.
Signed-off-by: Joshua Clayton <stillcompiling@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Move the input_tx code into its own small function.
This cleans up some variables from main() that are used only here.
While we are at it, check malloc calls instead of assuming they succeed.
Signed-off-by: Joshua Clayton <stillcompiling@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Jon Corbet requested this code moved with the last changeset,
https://lkml.org/lkml/2015/3/1/144,
but the patch was not applied because it missed the Makefile.
Moved spidev_test, spidev_fdx and their Makefile infrastructure.
Signed-off-by: Joshua Clayton <stillcompiling@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
If an event is discarded the device stays idle. Just reverse the order of
check and marking busy.
Found by code inspection.
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
We have varied reports of swizzling corruption on gen4 desktop, and
confirmation that one at least is triggered by uneven memory banks
(L-shaped memory). The implication is that the swizzling varies between
the paired channels and the remainder of memory on the single channel. As
the object then has unpredictable swizzling (it will vary depending on
exact page allocation and may even change during the object's lifetime as
the pages are replaced), we have to report to userspace that the swizzling
is unknown.
However, some existing userspace is buggy when it meets an unknown
swizzling configuration and so we need to tell another white lie and
mark the swizzling as NONE but report it as UNKNOWN through the extended
get-tiling-ioctl. See
commit 5eb3e5a5e1
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date: Sun Jun 28 09:19:26 2015 +0100
drm/i915: Declare the swizzling unknown for L-shaped configurations
for the previous example where we found that telling the truth to
userspace just ends up in a world of hurt.
Also since we don't truly know what the swizzling is on the pages, we
need to keep them pinned to prevent swapping as the reports also
suggest that some gen4 devices have previously undetected bit17
swizzling.
v2: Combine unknown + quirk patches to prevent userspace ever seeing
unknown swizzling through the normal get-tiling-ioctl. Also use the same
path for the existing uneven bank detection for mobile gen4.
Reported-by: Matti Hämäläinen <ccr@tnsp.org>
Tested-by: Matti Hämäläinen <ccr@tnsp.org>
References: https://bugs.freedesktop.org/show_bug.cgi?id=90725
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matti Hämäläinen <ccr@tnsp.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: stable@vger.kernel.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1447927085-31726-1-git-send-email-chris@chris-wilson.co.uk
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
kzalloc() can return NULL if it fails, and then we will be dereferencing
a NULL pointer.
Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch add the binding document of inno-rk3036
audio codec driver.
Signed-off-by: ZhengShunQian <zhengsq@rock-chips.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
sound/soc/codecs/inno_rk3036.c:480:3-8: No need to set .owner here. The core will do it.
Remove .owner field if calls are used which set it automatically
Generated by: scripts/coccinelle/api/platform_no_drv_owner.cocci
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
RK3036 SoC integrated with an Inno audio codec.
This driver implements the functions of it.
There is not need a special machine driver, since the
simple-card machine driver works perfect in this case.
Signed-off-by: ZhengShunQian <zhengsq@rock-chips.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch increments the management interface revision due to
introduction of a new Get Advertising Size Information command and
various other fixes & improvements.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
In order to enable advertising with privacy enabled, SMP has to be
registered in order to generate new RPA. During power on, it will be
registered at the very end which is the reason why advertising is not
enabled and it's not possible to enable it anymore due to mismatch
between hci_dev settings and actual controller state.
This fixes this problem by moving SMP registration earlier, just after
controller is powered (which is ok, because LE SMP will be already able
to decide on identity address to be used), but before advertising is
enabled.
Signed-off-by: Andrzej Kaczmarek <andrzej.kaczmarek@codecoup.pl>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The unsigned int variables [src|dst]_nents and nents can be assigned
signed value (-EINVAL) from sg_nents_for_len().
Furthermore they are used only by dma_map_sg and dma_unmap_sg which wait
for an signed int, so they must be set as int.
Fixes: f051f95eb4 ("crypto: picoxcell - check return value of sg_nents_for_len")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: LABBE Corentin <clabbe.montjoie@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The two unsigned int variables nb_in_sg and nb_out_sg can be assigned
signed value (-EINVAL) from sg_nents_for_len().
Furthermore they are used only by dma_map_sg and dma_unmap_sg which wait
for an signed int, so they must be set as int.
Fixes: 6c2b74d477 ("crypto: sahara - check return value of sg_nents_for_len")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: LABBE Corentin <clabbe.montjoie@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
We cannot put the HW RNG to idle using a timer because we cannot disable
clocks from atomic context. Use a delayed work instead.
Fixes a warning with CONFIG_DEBUG_MUTEXES on Nokia N900 during boot.
Reported-by: Sebastian Reichel <sre@kernel.org>
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The Atmel at91 crypto driver unconditionally selects AT_HDMAC,
which results in a Kconfig warning if that driver is not enabled:
warning: (CRYPTO_DEV_ATMEL_AES) selects AT_HDMAC which has unmet direct dependencies (DMADEVICES && ARCH_AT91)
The crypto driver itself does not actually have a dependency
on a particular dma engine, other than this being the one that
is used in at91.
Removing the 'select' gets rid of the warning, but can cause
the driver to be unusable if the HDMAC is not enabled at the
same time. To work around that, this patch clarifies the runtime
dependency to be 'AT_HDMAC || AT_XDMAC', but adds an alternative
for COMPILE_TEST, which lets the driver get build on all systems.
The ARCH_AT91 dependency is implied by AT_XDMAC || AT_HDMAC now
and no longer needs to be listed separately.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The key sizes used by AES in GCM mode should be 128, 192 or 256 bits (16,
24 or 32 bytes).
There is no additional 4byte nonce as for RFC 4106.
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The atmel AES driver assumes that 'int' and 'size_t' are the same
type in multiple locations, which the compiler warns about when
building it for 64-bit systems:
In file included from ../drivers/crypto/atmel-aes.c:17:0:
drivers/crypto/atmel-aes.c: In function 'atmel_aes_sg_copy':
include/linux/kernel.h:724:17: warning: comparison of distinct pointer types lacks a cast
drivers/crypto/atmel-aes.c:448:11: note: in expansion of macro 'min'
drivers/crypto/atmel-aes.c: In function 'atmel_aes_crypt_dma_stop':
include/linux/kern_levels.h:4:18: warning: format '%u' expects argument of type 'unsigned int', but argument 2 has type 'size_t {aka long unsigned int}' [-Wformat=]
This changes the format strings to use the %z modifier when printing
a size_t, and makes sure that we use the correct size_t type where
needed. In case of sg_dma_len(), the type of the result depends
on CONFIG_NEED_SG_DMA_LENGTH, so we have to use min_t to get it to
work in all configurations.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Simplify crypto_more_spawns() with list_first_entry_or_null()
and list_next_entry().
Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
There were a couple of code paths missed by the previous patch that
added a HCI status return parameter to __hci_req_sync. This patch adds
the missing assignments for them.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This adds support for the Panasonic panel found in some Xperia Z2
tablets.
Signed-off-by: Werner Johansson <werner.johansson@sonymobile.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Handle EPROBE_DEFER explicitly so that we ensure that we get the DMA
channel specified in the device tree, instead of depending on the DMA
controller getting probed before us.
Signed-off-by: Rabin Vincent <rabin.vincent@axis.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch adds device tree bindings for the Panasonic VVX10F034N00
WUXGA panel.
Signed-off-by: Werner Johansson <werner.johansson@sonymobile.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
We have requested the firmware but missed releasing it.
Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
When McASP is used as TX/RX synchronous (TX side generating clocks for RX
side also) and only capture is used we need to configure the number of TX
slots in order McASP to be able to generate the Frame sync.
Fixes: 9273de1940d9e ("ASoC: davinci-mcasp: Add set_tdm_slots() support")
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
RTC found in s2mps15 is almost same as one found on s2mps13
with few differences in RTC_UPDATE register fields, like:
1> Bit[4] and Bit[1] are reversed
- On s2mps13
WUDR -> bit[4], AUDR -> bit[1]
- On s2mps15
WUDR -> bit[1], AUDR -> bit[4]
2> In case of s2mps13, for alarm register, need to set both
WDUR and ADUR high, whereas for s2mps15 only set AUDR to high.
3> On s2mps15, WUDR, RUDR and AUDR functions should never be used
at the same time.
This patch add required changes to enable s2mps15 rtc timer.
Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
The S2MPS15 PMIC is similar in functionality to S2MPS11/14 PMIC. It contains
27 LDO and 10 Buck regulators and allows programming these regulators via a
I2C interface. This patch adds initial support for LDO/Buck regulators of
S2MPS15 PMIC.
Signed-off-by: Thomas Abraham <thomas.ab@samsung.com>
Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Add support for S2MPS15 PMIC which is similar to S2MPS11 PMIC. The S2MPS15
PMIC supports 27 LDO regulators, 10 buck regulators, RTC, three 32.768KHz
clock outputs and battery charger. This patch adds initial support for
LDO and buck regulators of S2MPS15 device.
Signed-off-by: Thomas Abraham <thomas.ab@samsung.com>
Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
[Alim: Added s2mps15_devs like rtc and clk and related changes]
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Several ARM default configurations give us warnings on recent
compilers about potentially uninitialized variables in the
nfnetlink code in two functions:
net/netfilter/nfnetlink_queue.c: In function 'nfqnl_build_packet_message':
net/netfilter/nfnetlink_queue.c:519:19: warning: 'nfnl_ct' may be used uninitialized in this function [-Wmaybe-uninitialized]
if (ct && nfnl_ct->build(skb, ct, ctinfo, NFQA_CT, NFQA_CT_INFO) < 0)
Moving the rcu_dereference(nfnl_ct_hook) call outside of the
conditional code avoids the warning without forcing us to
preinitialize the variable.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: a4b4766c3c ("netfilter: nfnetlink_queue: rename related to nfqueue attaching conntrack info")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Being able to examine page tables is handy, so make this a
module that can be loaded as needed.
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Vladimir Murzin <vladimir.murzin@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/20151120010755.GA9060@www.outflux.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
As result of commit "x86/xen: Avoid fast syscall path for Xen PV
guests", usergs_sysret32 pv op is not called by Xen PV guests
anymore and since they were the only ones who used it we can
safely remove it.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: david.vrabel@citrix.com
Cc: konrad.wilk@oracle.com
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1447970147-1733-4-git-send-email-boris.ostrovsky@oracle.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
As result of commit "x86/xen: Avoid fast syscall path for Xen PV
guests", the irq_enable_sysexit pv op is not called by Xen PV guests
anymore and since they were the only ones who used it we can
safely remove it.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: david.vrabel@citrix.com
Cc: konrad.wilk@oracle.com
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1447970147-1733-3-git-send-email-boris.ostrovsky@oracle.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
After 32-bit syscall rewrite, and specifically after commit:
5f310f739b ("x86/entry/32: Re-implement SYSENTER using the new C path")
... the stack frame that is passed to xen_sysexit is no longer a
"standard" one (i.e. it's not pt_regs).
Since we end up calling xen_iret from xen_sysexit we don't need
to fix up the stack and instead follow entry_SYSENTER_32's IRET
path directly to xen_iret.
We can do the same thing for compat mode even though stack does
not need to be fixed. This will allow us to drop usergs_sysret32
paravirt op (in the subsequent patch)
Suggested-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: david.vrabel@citrix.com
Cc: konrad.wilk@oracle.com
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1447970147-1733-2-git-send-email-boris.ostrovsky@oracle.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Running microcode_init() from setup_arch() is a bad idea because
not even kmalloc() is ready at that point and the loader does
all kinds of allocations and init/registration with various
subsystems.
Make it a late initcall when required facilities are initialized
so that the microcode driver initialization can succeed too.
Reported-and-tested-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20151120112400.GC4028@pd.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The flash loader has been seen on a Telit UE910 modem. The flash loader
is a bit special, it presents both an ACM and CDC Data interface but
only the latter is useful. Unless a magic string is sent to the device
it will disappear and the regular modem device appears instead.
Signed-off-by: Jonas Jonsson <jonas@ludd.ltu.se>
Tested-by: Daniele Palmas <dnlplm@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Some modems, such as the Telit UE910, are using an Infineon Flash Loader
utility. It has two interfaces, 2/2/0 (Abstract Modem) and 10/0/0 (CDC
Data). The latter can be used as a serial interface to upgrade the
firmware of the modem. However, that isn't possible when the cdc-acm
driver takes control of the device.
The following is an explanation of the behaviour by Daniele Palmas during
discussion on linux-usb.
"This is what happens when the device is turned on (without modifying
the drivers):
[155492.352031] usb 1-3: new high-speed USB device number 27 using ehci-pci
[155492.485429] usb 1-3: config 1 interface 0 altsetting 0 endpoint 0x81 has an invalid bInterval 255, changing to 11
[155492.485436] usb 1-3: New USB device found, idVendor=058b, idProduct=0041
[155492.485439] usb 1-3: New USB device strings: Mfr=0, Product=0, SerialNumber=0
[155492.485952] cdc_acm 1-3:1.0: ttyACM0: USB ACM device
This is the flashing device that is caught by the cdc-acm driver. Once
the ttyACM appears, the application starts sending a magic string
(simple write on the file descriptor) to keep the device in flashing
mode. If this magic string is not properly received in a certain time
interval, the modem goes on in normal operative mode:
[155493.748094] usb 1-3: USB disconnect, device number 27
[155494.916025] usb 1-3: new high-speed USB device number 28 using ehci-pci
[155495.059978] usb 1-3: New USB device found, idVendor=1bc7, idProduct=0021
[155495.059983] usb 1-3: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[155495.059986] usb 1-3: Product: 6 CDC-ACM + 1 CDC-ECM
[155495.059989] usb 1-3: Manufacturer: Telit
[155495.059992] usb 1-3: SerialNumber: 359658044004697
[155495.138958] cdc_acm 1-3:1.0: ttyACM0: USB ACM device
[155495.140832] cdc_acm 1-3:1.2: ttyACM1: USB ACM device
[155495.142827] cdc_acm 1-3:1.4: ttyACM2: USB ACM device
[155495.144462] cdc_acm 1-3:1.6: ttyACM3: USB ACM device
[155495.145967] cdc_acm 1-3:1.8: ttyACM4: USB ACM device
[155495.147588] cdc_acm 1-3:1.10: ttyACM5: USB ACM device
[155495.154322] cdc_ether 1-3:1.12 wwan0: register 'cdc_ether' at usb-0000:00:1a.7-3, Mobile Broadband Network Device, 00:00:11:12:13:14
Using the cdc-acm driver, the string, though being sent in the same way
than using the usb-serial-simple driver (I can confirm that the data is
passing properly since I used an hw usb sniffer), does not make the
device to stay in flashing mode."
Signed-off-by: Jonas Jonsson <jonas@ludd.ltu.se>
Tested-by: Daniele Palmas <dnlplm@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
CP2110 ID (0x10c4, 0xea80) doesn't belong here because it's a HID
and completely different from CP210x devices.
Signed-off-by: Konstantin Shkolnyy <konstantin.shkolnyy@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Currently we can hit a scenario where we'll tm_reclaim() twice. This
results in a TM bad thing exception because the second reclaim occurs
when not in suspend mode.
The scenario in which this can happen is the following. We attempt to
deliver a signal to userspace. To do this we need obtain the stack
pointer to write the signal context. To get this stack pointer we
must tm_reclaim() in case we need to use the checkpointed stack
pointer (see get_tm_stackpointer()). Normally we'd then return
directly to userspace to deliver the signal without going through
__switch_to().
Unfortunatley, if at this point we get an error (such as a bad
userspace stack pointer), we need to exit the process. The exit will
result in a __switch_to(). __switch_to() will attempt to save the
process state which results in another tm_reclaim(). This
tm_reclaim() now causes a TM Bad Thing exception as this state has
already been saved and the processor is no longer in TM suspend mode.
Whee!
This patch checks the state of the MSR to ensure we are TM suspended
before we attempt the tm_reclaim(). If we've already saved the state
away, we should no longer be in TM suspend mode. This has the
additional advantage of checking for a potential TM Bad Thing
exception.
Found using syscall fuzzer.
Fixes: fb09692e71 ("powerpc: Add reclaim and recheckpoint functions for context switching transactional memory processes")
Cc: stable@vger.kernel.org # v3.9+
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Currently we allow both the MSR T and S bits to be set by userspace on
a signal return. Unfortunately this is a reserved configuration and
will cause a TM Bad Thing exception if attempted (via rfid).
This patch checks for this case in both the 32 and 64 bit signals
code. If both T and S are set, we mark the context as invalid.
Found using a syscall fuzzer.
Fixes: 2b0a576d15 ("powerpc: Add new transactional memory state to the signal context")
Cc: stable@vger.kernel.org # v3.9+
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The unlock function in queued spinlocks was optimized for better
performance on bare metal systems at the expense of virtualized guests.
For x86-64 systems, the unlock call needs to go through a
PV_CALLEE_SAVE_REGS_THUNK() which saves and restores 8 64-bit
registers before calling the real __pv_queued_spin_unlock()
function. The thunk code may also be in a separate cacheline from
__pv_queued_spin_unlock().
This patch optimizes the PV unlock code path by:
1) Moving the unlock slowpath code from the fastpath into a separate
__pv_queued_spin_unlock_slowpath() function to make the fastpath
as simple as possible..
2) For x86-64, hand-coded an assembly function to combine the register
saving thunk code with the fastpath code. Only registers that
are used in the fastpath will be saved and restored. If the
fastpath fails, the slowpath function will be called via another
PV_CALLEE_SAVE_REGS_THUNK(). For 32-bit, it falls back to the C
__pv_queued_spin_unlock() code as the thunk saves and restores
only one 32-bit register.
With a microbenchmark of 5M lock-unlock loop, the table below shows
the execution times before and after the patch with different number
of threads in a VM running on a 32-core Westmere-EX box with x86-64
4.2-rc1 based kernels:
Threads Before patch After patch % Change
------- ------------ ----------- --------
1 134.1 ms 119.3 ms -11%
2 1286 ms 953 ms -26%
3 3715 ms 3480 ms -6.3%
4 4092 ms 3764 ms -8.0%
Signed-off-by: Waiman Long <Waiman.Long@hpe.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Douglas Hatch <doug.hatch@hpe.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Scott J Norton <scott.norton@hpe.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1447114167-47185-5-git-send-email-Waiman.Long@hpe.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
With optimistic prefetch of the next node cacheline, the next pointer
may have been properly inititalized. As a result, the reading
of node->next in the contended path may be redundant. This patch
eliminates the redundant read if the next pointer value is not NULL.
Signed-off-by: Waiman Long <Waiman.Long@hpe.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Douglas Hatch <doug.hatch@hpe.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Scott J Norton <scott.norton@hpe.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1447114167-47185-4-git-send-email-Waiman.Long@hpe.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
A queue head CPU, after acquiring the lock, will have to notify
the next CPU in the wait queue that it has became the new queue
head. This involves loading a new cacheline from the MCS node of the
next CPU. That operation can be expensive and add to the latency of
locking operation.
This patch addes code to optmistically prefetch the next MCS node
cacheline if the next pointer is defined and it has been spinning
for the MCS lock for a while. This reduces the locking latency and
improves the system throughput.
The performance change will depend on whether the prefetch overhead
can be hidden within the latency of the lock spin loop. On really
short critical section, there may not be performance gain at all. With
longer critical section, however, it was found to have a performance
boost of 5-10% over a range of different queue depths with a spinlock
loop microbenchmark.
Signed-off-by: Waiman Long <Waiman.Long@hpe.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Douglas Hatch <doug.hatch@hpe.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Scott J Norton <scott.norton@hpe.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1447114167-47185-3-git-send-email-Waiman.Long@hpe.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch replaces the cmpxchg() and xchg() calls in the native
qspinlock code with the more relaxed _acquire or _release versions of
those calls to enable other architectures to adopt queued spinlocks
with less memory barrier performance overhead.
Signed-off-by: Waiman Long <Waiman.Long@hpe.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Douglas Hatch <doug.hatch@hpe.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Scott J Norton <scott.norton@hpe.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1447114167-47185-2-git-send-email-Waiman.Long@hpe.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Some atomic operations now have _relaxed/acquire/release variants, this
patch adds some trivial tests for two purposes:
1. test the behavior of these new operations in single-CPU
environment.
2. make their code generated before we actually use them somewhere,
so that we can examine their assembly code.
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <waiman.long@hp.com>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/1446634365-25176-1-git-send-email-boqun.feng@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
