The DMAengine API has a long standing race condition that is inherent to
the API itself. Calling dmaengine_terminate_all() is supposed to stop and
abort any pending or active transfers that have previously been submitted.
Unfortunately it is possible that this operation races against a currently
running (or with some drivers also scheduled) completion callback.
Since the API allows dmaengine_terminate_all() to be called from atomic
context as well as from within a completion callback it is not possible to
synchronize to the execution of the completion callback from within
dmaengine_terminate_all() itself.
This means that a user of the DMAengine API does not know when it is safe
to free resources used in the completion callback, which can result in a
use-after-free race condition.
This patch addresses the issue by introducing an explicit synchronization
primitive to the DMAengine API called dmaengine_synchronize().
The existing dmaengine_terminate_all() is deprecated in favor of
dmaengine_terminate_sync() and dmaengine_terminate_async(). The former
aborts all pending and active transfers and synchronizes to the current
context, meaning it will wait until all running completion callbacks have
finished. This means it is only possible to call this function from
non-atomic context. The later function does not synchronize, but can still
be used in atomic context or from within a complete callback. It has to be
followed up by dmaengine_synchronize() before a client can free the
resources used in a completion callback.
In addition to this the semantics of the device_terminate_all() callback
are slightly relaxed by this patch. It is now OK for a driver to only
schedule the termination of the active transfer, but does not necessarily
have to wait until the DMA controller has completely stopped. The driver
must ensure though that the controller has stopped and no longer accesses
any memory when the device_synchronize() callback returns.
This was in part done since most drivers do not pay attention to this
anyway at the moment and to emphasize that this needs to be done when the
device_synchronize() callback is implemented. But it also helps with
implementing support for devices where stopping the controller can require
operations that may sleep.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Pull perf updates from Thomas Gleixner:
"Mostly updates to the perf tool plus two fixes to the kernel core code:
- Handle tracepoint filters correctly for inherited events (Peter
Zijlstra)
- Prevent a deadlock in perf_lock_task_context (Paul McKenney)
- Add missing newlines to some pr_err() calls (Arnaldo Carvalho de
Melo)
- Print full source file paths when using 'perf annotate --print-line
--full-paths' (Michael Petlan)
- Fix 'perf probe -d' when just one out of uprobes and kprobes is
enabled (Wang Nan)
- Add compiler.h to list.h to fix 'make perf-tar-src-pkg' generated
tarballs, i.e. out of tree building (Arnaldo Carvalho de Melo)
- Add the llvm-src-base.c and llvm-src-kbuild.c files, generated by
the 'perf test' LLVM entries, when running it in-tree, to
.gitignore (Yunlong Song)
- libbpf error reporting improvements, using a strerror interface to
more precisely tell the user about problems with the provided
scriptlet, be it in C or as a ready made object file (Wang Nan)
- Do not be case sensitive when searching for matching 'perf test'
entries (Arnaldo Carvalho de Melo)
- Inform the user about objdump failures in 'perf annotate' (Andi
Kleen)
- Improve the LLVM 'perf test' entry, introduce a new ones for BPF
and kbuild tests to check the environment used by clang to compile
.c scriptlets (Wang Nan)"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits)
perf/x86/intel/rapl: Remove the unused RAPL_EVENT_DESC() macro
tools include: Add compiler.h to list.h
perf probe: Verify parameters in two functions
perf session: Add missing newlines to some pr_err() calls
perf annotate: Support full source file paths for srcline fix
perf test: Add llvm-src-base.c and llvm-src-kbuild.c to .gitignore
perf: Fix inherited events vs. tracepoint filters
perf: Disable IRQs across RCU RS CS that acquires scheduler lock
perf test: Do not be case sensitive when searching for matching tests
perf test: Add 'perf test BPF'
perf test: Enhance the LLVM tests: add kbuild test
perf test: Enhance the LLVM test: update basic BPF test program
perf bpf: Improve BPF related error messages
perf tools: Make fetch_kernel_version() publicly available
bpf tools: Add new API bpf_object__get_kversion()
bpf tools: Improve libbpf error reporting
perf probe: Cleanup find_perf_probe_point_from_map to reduce redundancy
perf annotate: Inform the user about objdump failures in --stdio
perf stat: Make stat options global
perf sched latency: Fix thread pid reuse issue
...
Pull scheduler fix from Thomas Gleixner:
"A single fix to prevent math underflow in the numa balancing code"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/numa: Fix math underflow in task_tick_numa()
Pull liblockdep fixes from Thomas Gleixner:
"Three small patches to synchronize liblockdep with the latest core
changes"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tools/liblockdep: explicitly declare lockdep API we call from liblockdep
tools/liblockdep: add userspace versions of WRITE_ONCE and RCU_INIT_POINTER
tools/liblockdep: remove task argument from debug_check_no_locks_held
Pull x86 fixes from Thomas Gleixner:
"A couple of fixes and updates related to x86:
- Fix the W+X check regression on XEN
- The real fix for the low identity map trainwreck
- Probe legacy PIC early instead of unconditionally allocating legacy
irqs
- Add cpu verification to long mode entry
- Adjust the cache topology to AMD Fam17H systems
- Let Merrifield use the TSC across S3"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/cpu: Call verify_cpu() after having entered long mode too
x86/setup: Fix low identity map for >= 2GB kernel range
x86/mm: Skip the hypervisor range when walking PGD
x86/AMD: Fix last level cache topology for AMD Fam17h systems
x86/irq: Probe for PIC presence before allocating descs for legacy IRQs
x86/cpu/intel: Enable X86_FEATURE_NONSTOP_TSC_S3 for Merrifield
Pull irq and timer fixes from Thomas Gleixner:
- An irq regression fix to restore the wakeup behaviour of chained
interrupts.
- A timer fix for a long standing race versus timers scheduled on a
target cpu which got exposed by recent changes in the workqueue
implementation.
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq/PM: Restore system wake up from chained interrupts
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timers: Use proper base migration in add_timer_on()
Pull MIPS updates from Ralf Baechle:
"These are the highlists of the main MIPS pull request for 4.4:
- Add latencytop support
- Support appended DTBs
- VDSO support and initially use it for gettimeofday.
- Drop the .MIPS.abiflags and ELF NOTE sections from vmlinux
- Support for the 5KE, an internal test core.
- Switch all MIPS platfroms to libata drivers.
- Improved support, cleanups for ralink and Lantiq platforms.
- Support for the new xilfpga platform.
- A number of DTB improvments for BMIPS.
- Improved support for CM and CPS.
- Minor JZ4740 and BCM47xx enhancements"
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (120 commits)
MIPS: idle: add case for CPU_5KE
MIPS: Octeon: Support APPENDED_DTB
MIPS: vmlinux: create a section for appended DTB
MIPS: Clean up compat_siginfo_t
MIPS: Fix PAGE_MASK definition
MIPS: BMIPS: Enable GZIP ramdisk and timed printks
MIPS: Add xilfpga defconfig
MIPS: xilfpga: Add mipsfpga platform code
MIPS: xilfpga: Add xilfpga device tree files.
dt-bindings: MIPS: Document xilfpga bindings and boot style
MIPS: Make MIPS_CMDLINE_DTB default
MIPS: Make the kernel arguments from dtb available
MIPS: Use USE_OF as the guard for appended dtb
MIPS: BCM63XX: Use pr_* instead of printk
MIPS: Loongson: Cleanup CONFIG_LOONGSON_SUSPEND.
MIPS: lantiq: Disable xbar fpi burst mode
MIPS: lantiq: Force the crossbar to big endian
MIPS: lantiq: Initialize the USB core on boot
MIPS: lantiq: Return correct value for fpi clock on ar9
MIPS: ralink: Add missing clock on rt305x
...
Pull sound fixes from Takashi Iwai:
"Here are a collection of small fixes tha have been gathered for
4.4-rc1. The only significant changes are those in PCI drivers
Kconfig, to use "depends on" instead of "select" for CONFIG_ZONE_DMA.
A reverse select is often more user-friendly, but in this case, it
makes hard to manage with the conflict with ZONE_DEVICE, so changed in
such a way for now.
Others are all small fixes and quirks: an error check in soundcore
reigster_chrdev(), HD-audio HDMI/DP phantom jack fix, Intel Broxton DP
quirk, USB-audio DSD device quirk, some constifications, etc"
* tag 'sound-fix-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: pci: depend on ZONE_DMA
ALSA: hda - Simplify phantom jack handling for HDMI/DP
ALSA: hda/hdmi - apply Skylake fix-ups to Broxton display codec
ALSA: ctxfi: constify rsc ops structures
ALSA: usb: Add native DSD support for Aune X1S
ALSA: oxfw: add an comment to Kconfig for TASCAM FireOne
sound: fix check for error condition of register_chrdev()
Pull ARC fixes from Vineet Gupta:
"Found a couple of brown paper bag bugs with the prev pull request
(including a SMP build breakage report from Guenter). Since these are
urgent I also decided to send over a bunch of other pending fixes
which could have otherwise waited an rc or two.
Summary:
- A bunch of brown paper bag bugs (MAINTAINERS list email, SMP build
failure)
- cpu_relax() now compiler barrier for UP as well
- handling of userspace Bus Errors for ARCompact builds"
* tag 'arc-4.4-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
ARC: Fix silly typo in MAINTAINERS file
ARC: cpu_relax() to be compiler barrier even for UP
ARC: use ASL assembler mnemonic
ARC: [arcompact] Handle bus error from userspace as Interrupt not exception
ARC: remove extraneous header include
ARCv2: lib: memcpy: use local symbols
ARCompact and ARCv2 only have ASL, while binutils used to support LSL as
a alias mnemonic.
Newer binutils (upstream) don't want to do that so replace it.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Bus errors from userspace on ARCompact based cores are handled by core
as a high priority L2 interrupt but current code treated it as interrupt
Handling an interrupt like exception is certainly not going to go unnoticed.
(and it worked so far as we never saw a Bus error from userspace until
IPPK guys tested a DDR controller with ECC error detection etc hence
needed to explicitly trigger/handle such errors)
- So move mem_service exception handler from common code into ARCv2 code.
- In ARCompact code, define mem_service as L2 interrupt handler which
just drops down to pure kernel mode and goes of to enqueue SIGBUS
Reported-by: Nelson Pereira <npereira@synopsys.com>
Tested-by: Ana Martins <amartins@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Pull chrome platform updates from Olof Johansson:
"Here's the branch of chrome platform changes for v4.4. Some have been
queued up for the full 4.3 release cycle since I forgot to send them
in for that round (rebased early on to deal with fixes conflicts).
Most of these enable EC communication stuff -- Pixel 2015 support,
enabling building for ARM64 platforms, and a few fixes for memory
leaks.
There's also a patch in here to allow reading/writing the verified
boot context, which depends on a sysfs patch acked by Greg"
* tag 'chrome-platform-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/olof/chrome-platform:
platform/chrome: Fix i2c-designware adapter name
platform/chrome: Support reading/writing the vboot context
sysfs: Support is_visible() on binary attributes
platform/chrome: cros_ec: Fix possible leak in led_rgb_store()
platform/chrome: cros_ec: Fix leak in sequence_store()
platform/chrome: Enable Chrome platforms on 64-bit ARM
platform/chrome: cros_ec_dev - Add a platform device ID table
platform/chrome: cros_ec_lpc - Add support for Google Pixel 2
platform/chrome: cros_ec_lpc - Use existing function to check EC result
platform/chrome: Make depends on MFD_CROS_EC instead CROS_EC_PROTO
Revert "platform/chrome: Don't make CHROME_PLATFORMS depends on X86 || ARM"
Pull another x86 platform driver update from Darren Hart:
"Support for the unfortunately rather unique ESC key on the Ideapad
Yoga 3 and two DMI matches for rfkill support. Solitary fix for
potential missed errors for asus-wmi. Downgrade a thinkpad_acpi
message to info.
asus-wmi:
- fix error handling in store_sys_wmi()
ideapad-laptop:
- Add Lenovo Yoga 900 to no_hw_rfkill dmi list
- include Yoga 3 1170 in add rfkill whitelist
- add support for Yoga 3 ESC key
thinkpad_acpi:
- Don't yell on unsupported brightness interfaces"
* tag 'platform-drivers-x86-v4.4-2' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86:
asus-wmi: fix error handling in store_sys_wmi()
ideapad-laptop: Add Lenovo Yoga 900 to no_hw_rfkill dmi list
ideapad-laptop: include Yoga 3 1170 in add rfkill whitelist
ideapad-laptop: add support for Yoga 3 ESC key
thinkpad_acpi: Don't yell on unsupported brightness interfaces
Pull more input updates from Dmitry Torokhov:
"An update to the tsc2005 driver that allows it to also support tsc2004
(basically the same controller, but uses i2c instead of spi bus), and
a couple of bug fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: parkbd - drop bogus __init from parkbd_allocate_serio()
Input: elantech - add Fujitsu Lifebook U745 to force crc_enabled
Input: tsc2004 - add support for tsc2004
Input: tsc200x-core - rename functions and variables
Input: tsc2005 - separate SPI and core functions
Pull final round of SCSI updates from James Bottomley:
"Sorry for the delay in this patch which was mostly caused by getting
the merger of the mpt2/mpt3sas driver, which was seen as an essential
item of maintenance work to do before the drivers diverge too much.
Unfortunately, this caused a compile failure (detected by linux-next),
which then had to be fixed up and incubated.
In addition to the mpt2/3sas rework, there are updates from pm80xx,
lpfc, bnx2fc, hpsa, ipr, aacraid, megaraid_sas, storvsc and ufs plus
an assortment of changes including some year 2038 issues, a fix for a
remove before detach issue in some drivers and a couple of other minor
issues"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (141 commits)
mpt3sas: fix inline markers on non inline function declarations
sd: Clear PS bit before Mode Select.
ibmvscsi: set max_lun to 32
ibmvscsi: display default value for max_id, max_lun and max_channel.
mptfusion: don't allow negative bytes in kbuf_alloc_2_sgl()
scsi: pmcraid: replace struct timeval with ktime_get_real_seconds()
mvumi: 64bit value for seconds_since1970
be2iscsi: Fix bogus WARN_ON length check
scsi_scan: don't dump trace when scsi_prep_async_scan() is called twice
mpt3sas: Bump mpt3sas driver version to 09.102.00.00
mpt3sas: Single driver module which supports both SAS 2.0 & SAS 3.0 HBAs
mpt2sas, mpt3sas: Update the driver versions
mpt3sas: setpci reset kernel oops fix
mpt3sas: Added OEM Gen2 PnP ID branding names
mpt3sas: Refcount fw_events and fix unsafe list usage
mpt3sas: Refcount sas_device objects and fix unsafe list usage
mpt3sas: sysfs attribute to report Backup Rail Monitor Status
mpt3sas: Ported WarpDrive product SSS6200 support
mpt3sas: fix for driver fails EEH, recovery from injected pci bus error
mpt3sas: Manage MSI-X vectors according to HBA device type
...
Pull SCSI target updates from Nicholas Bellinger:
"This series contains HCH's changes to absorb configfs attribute
->show() + ->store() function pointer usage from it's original
tree-wide consumers, into common configfs code.
It includes usb-gadget, target w/ drivers, netconsole and ocfs2
changes to realize the improved simplicity, that now renders the
original include/target/configfs_macros.h CPP magic for fabric drivers
and others, unnecessary and obsolete.
And with common code in place, new configfs attributes can be added
easier than ever before.
Note, there are further improvements in-flight from other folks for
v4.5 code in configfs land, plus number of target fixes for post -rc1
code"
In the meantime, a new user of the now-removed old configfs API came in
through the char/misc tree in commit 7bd1d4093c ("stm class: Introduce
an abstraction for System Trace Module devices").
This merge resolution comes from Alexander Shishkin, who updated his stm
class tracing abstraction to account for the removal of the old
show_attribute and store_attribute methods in commit 517982229f
("configfs: remove old API") from this pull. As Alexander says about
that patch:
"There's no need to keep an extra wrapper structure per item and the
awkward show_attribute/store_attribute item ops are no longer needed.
This patch converts policy code to the new api, all the while making
the code quite a bit smaller and easier on the eyes.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>"
That patch was folded into the merge so that the tree should be fully
bisectable.
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (23 commits)
configfs: remove old API
ocfs2/cluster: use per-attribute show and store methods
ocfs2/cluster: move locking into attribute store methods
netconsole: use per-attribute show and store methods
target: use per-attribute show and store methods
spear13xx_pcie_gadget: use per-attribute show and store methods
dlm: use per-attribute show and store methods
usb-gadget/f_serial: use per-attribute show and store methods
usb-gadget/f_phonet: use per-attribute show and store methods
usb-gadget/f_obex: use per-attribute show and store methods
usb-gadget/f_uac2: use per-attribute show and store methods
usb-gadget/f_uac1: use per-attribute show and store methods
usb-gadget/f_mass_storage: use per-attribute show and store methods
usb-gadget/f_sourcesink: use per-attribute show and store methods
usb-gadget/f_printer: use per-attribute show and store methods
usb-gadget/f_midi: use per-attribute show and store methods
usb-gadget/f_loopback: use per-attribute show and store methods
usb-gadget/ether: use per-attribute show and store methods
usb-gadget/f_acm: use per-attribute show and store methods
usb-gadget/f_hid: use per-attribute show and store methods
...
Pull libnvdimm fixes from Dan Williams:
- three fixes tagged for -stable including a crash fix, simple
performance tweak, and an invalid i/o error.
- build regression fix for the nvdimm unit tests
- nvdimm documentation update
* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
dax: fix __dax_pmd_fault crash
libnvdimm: documentation clarifications
libnvdimm, pmem: fix size trim in pmem_direct_access()
libnvdimm, e820: fix numa node for e820-type-12 pmem ranges
tools/testing/nvdimm, acpica: fix flag rename build breakage
Now that the xattr handler is passed to the xattr handler operations, we
have access to the attribute name prefix, so simplify the squashfs xattr
handlers a bit.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Phillip Lougher <phillip@squashfs.org.uk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Now that the xattr handler is passed to the xattr handler operations, we
can use the same get and set operations for the user, trusted, and security
xattr namespaces. In those namespaces, we can access the full attribute
name by "reattaching" the name prefix the vfs has skipped for us. Add a
xattr_full_name helper to make this obvious in the code.
For the "system.posix_acl_access" and "system.posix_acl_default"
attributes, handler->prefix is the full attribute name; the suffix is the
empty string.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Cc: v9fs-developer@lists.sourceforge.net
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Lars-Peter Clausen
Linus Torvalds
Vineet Gupta
Andreas Gruenbacher