In coresight-funnel drivers, cti_drvdata->spinlock can be held
during __schedule() by perf_event_task_sched_out()/in().
Since funnel_drvdata->spinlock type is spinlock_t and
perf_event_task_sched_out()/in() is called after acquiring rq_lock,
which is raw_spinlock_t (an unsleepable lock),
this poses an issue in PREEMPT_RT kernel where spinlock_t is sleepable.
To address this, change type funnel_drvdata->spinlock in
coresight-funnel drivers, which can be called by
perf_event_task_sched_out()/in(), from spinlock_t to raw_spinlock_t.
Signed-off-by: Yeoreum Yun <yeoreum.yun@arm.com>
Reviewed-by: James Clark <james.clark@linaro.org>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250306121110.1647948-7-yeoreum.yun@arm.com
In coresight-etb10 drivers, etb_drvdata->spinlock can be held
during __schedule() by perf_event_task_sched_out()/in().
Since etb_drvdata->spinlock type is spinlock_t and
perf_event_task_sched_out()/in() is called after acquiring rq_lock,
which is raw_spinlock_t (an unsleepable lock),
this poses an issue in PREEMPT_RT kernel where spinlock_t is sleepable.
To address this, change type etb_drvdata->spinlock in coresight-etb10 drivers,
which can be called by perf_event_task_sched_out()/in(),
from spinlock_t to raw_spinlock_t.
Reviewed-by: James Clark <james.clark@linaro.org>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Yeoreum Yun <yeoreum.yun@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250306121110.1647948-6-yeoreum.yun@arm.com
In coresight-cti drivers, cti_drvdata->spinlock can be held during __schedule()
by perf_event_task_sched_out()/in().
Since cti_drvdata->spinlock type is spinlock_t and
perf_event_task_sched_out()/in() is called after acquiring rq_lock,
which is raw_spinlock_t (an unsleepable lock),
this poses an issue in PREEMPT_RT kernel where spinlock_t is sleepable.
To address this, change type cti_drvdata->spinlock in coresight-cti drivers,
which can be called by perf_event_task_sched_out()/in(),
from spinlock_t to raw_spinlock_t.
Reviewed-by: James Clark <james.clark@linaro.org>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Yeoreum Yun <yeoreum.yun@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250306121110.1647948-5-yeoreum.yun@arm.com
coresight_trace_id_map->lock can be acquired while coresight devices'
drvdata_lock.
But the drvdata_lock can be raw_spinlock_t (i.e) coresight-etm4x.
To address this, change type of coresight_trace_id_map->lock to
raw_spinlock_t
Signed-off-by: Yeoreum Yun <yeoreum.yun@arm.com>
Reviewed-by: James Clark <james.clark@linaro.org>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250306121110.1647948-4-yeoreum.yun@arm.com
In coresight-etm4x drivers, etmv4_drvdata->spinlock can be held during
__schedule() by perf_event_task_sched_out()/in().
Since etmv4_drvdata->spinlock type is spinlock_t and
perf_event_task_sched_out()/in() is called after acquiring rq_lock,
which is raw_spinlock_t (an unsleepable lock),
this poses an issue in PREEMPT_RT kernel where spinlock_t is sleepable.
To address this, change type etmv4_drvdata->spinlock
in coresight-etm4x drivers, which can be called
by perf_event_task_sched_out()/in(), from spinlock_t to raw_spinlock_t.
Signed-off-by: Yeoreum Yun <yeoreum.yun@arm.com>
Reviewed-by: James Clark <james.clark@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250306121110.1647948-3-yeoreum.yun@arm.com
coresight_device->cscfg_csdev_lock can be held during __schedule()
by perf_event_task_sched_out()/in().
Since coresight->cscfg_csdev_lock type is spinlock_t and
perf_event_task_sched_out()/in() is called after acquiring rq_lock,
which is raw_spinlock_t (an unsleepable lock),
this poses an issue in PREEMPT_RT kernel where spinlock_t is sleepable.
To address this, change type of coresight_device->cscfg_csdev_lock
from spinlock_t to raw_spinlock_t.
Reviewed-by: James Clark <james.clark@linaro.org>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Yeoreum Yun <yeoreum.yun@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250306121110.1647948-2-yeoreum.yun@arm.com
The coresight_etm_get_trace_id function is a global function. The
verification process for 'csdev' is required prior to its usage.
Fixes: c367a89dec ("Coresight: Add trace_id function to retrieving the trace ID")
Signed-off-by: Jie Gan <quic_jiegan@quicinc.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250310102724.2112905-1-quic_jiegan@quicinc.com
The Coresight TMC Control Unit hosts miscellaneous configuration registers
which control various features related to TMC ETR sink.
Based on the trace ID, which is programmed in the related CTCU ATID
register of a specific ETR, trace data with that trace ID gets into
the ETR buffer, while other trace data gets dropped.
Enabling source device sets one bit of the ATID register based on
source device's trace ID.
Disabling source device resets the bit according to the source
device's trace ID.
Reviewed-by: James Clark <james.clark@linaro.org>
Signed-off-by: Jie Gan <quic_jiegan@quicinc.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250303032931.2500935-10-quic_jiegan@quicinc.com
Add binding file to specify how to define a Coresight TMC Control Unit device
in device tree.
It is responsible for controlling the data filter function based on the source
device's Trace ID for TMC ETR device. The trace data with that Trace id can get
into ETR's buffer while other trace data gets ignored.
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Jie Gan <quic_jiegan@quicinc.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250303032931.2500935-9-quic_jiegan@quicinc.com
Modify following functions to accept the coresight_path. Devices in the path
can read data from coresight_path if needed.
- coresight_enable_path
- coresight_disable_path
- coresight_get_source
- coresight_get_sink
- coresight_enable_helpers
- coresight_disable_helpers
Signed-off-by: Jie Gan <quic_jiegan@quicinc.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250303032931.2500935-8-quic_jiegan@quicinc.com
The source device can directly read the trace ID from the coresight_path
which result in etm_read_alloc_trace_id and etm4_read_alloc_trace_id being
deleted.
Co-developed-by: James Clark <james.clark@linaro.org>
Signed-off-by: James Clark <james.clark@linaro.org>
Signed-off-by: Jie Gan <quic_jiegan@quicinc.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250303032931.2500935-7-quic_jiegan@quicinc.com
The trace_id will be stored in coresight_path instead of being declared
everywhere and allocated after building the path.
Co-developed-by: James Clark <james.clark@linaro.org>
Signed-off-by: James Clark <james.clark@linaro.org>
Signed-off-by: Jie Gan <quic_jiegan@quicinc.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250303032931.2500935-6-quic_jiegan@quicinc.com
Introduce a new strcuture, 'struct coresight_path', to store the data that
utilized by the devices in the path. The coresight_path will be built/released
by coresight_build_path/coresight_release_path functions.
Signed-off-by: Jie Gan <quic_jiegan@quicinc.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250303032931.2500935-5-quic_jiegan@quicinc.com
Use the new API, coresight_etm_get_trace_id, to read the traceid of the ETM
device when call traceid_show via sysfs node.
Signed-off-by: James Clark <james.clark@linaro.org>
Reviewed-by: James Clark <james.clark@linaro.org>
Signed-off-by: Jie Gan <quic_jiegan@quicinc.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250303032931.2500935-4-quic_jiegan@quicinc.com
Add 'trace_id' function pointer in coresight_ops. It's responsible for retrieving
the device's trace ID.
Co-developed-by: James Clark <james.clark@linaro.org>
Signed-off-by: James Clark <james.clark@linaro.org>
Reviewed-by: James Clark <james.clark@linaro.org>
Signed-off-by: Jie Gan <quic_jiegan@quicinc.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250303032931.2500935-3-quic_jiegan@quicinc.com
Add support for new APB clock-name. If the function fails
to obtain the clock with the name "apb_pclk", it will
attempt to acquire the clock with the name "apb".
Reviewed-by: James Clark <james.clark@linaro.org>
Signed-off-by: Jie Gan <quic_jiegan@quicinc.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250303032931.2500935-2-quic_jiegan@quicinc.com
Binding listed variable number of IO addresses without defining them,
however example DTS code, all in-tree DTS and Linux kernel driver
mention only one address space, so drop the second to make binding
precise and correctly describe the hardware.
Fixes: 6c781a3513 ("dt-bindings: arm: Add CoreSight TPDM hardware")
Cc: stable@vger.kernel.org
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250226112914.94361-2-krzysztof.kozlowski@linaro.org
Binding listed variable number of IO addresses without defining them,
however example DTS code, all in-tree DTS and Linux kernel driver
mention only one address space, so drop the second to make binding
precise and correctly describe the hardware.
Fixes: a8fbe1442c ("dt-bindings: arm: Adds CoreSight TPDA hardware definitions")
Cc: stable@vger.kernel.org
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250226112914.94361-1-krzysztof.kozlowski@linaro.org
Add the sysfs file to set/get the enablement of the lane. For MCMB
configurations, the field "E_LN" in CMB_CR register is the
individual lane enables. MCMB lane N is enabled for trace
generation when M_CMB_CR.E=1 and M_CMB_CR.E_LN[N]=1. For lanes
that are not implemented on a given MCMB configuration, the
corresponding bits of this field read as 0 and ignore writes.
Signed-off-by: Tao Zhang <quic_taozha@quicinc.com>
Signed-off-by: Mao Jinlong <quic_jinlmao@quicinc.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250226064008.2531037-4-quic_jinlmao@quicinc.com
TPDM MCMB subunits supports up to 8 lanes CMB. For MCMB
configurations, the field "XTRIG_LNSEL" in CMB_CR register selects
which lane participates in the output pattern mach cross trigger
mechanism governed by the M_CMB_DXPR and M_CMB_XPMR regisers.
Signed-off-by: Tao Zhang <quic_taozha@quicinc.com>
Signed-off-by: Mao Jinlong <quic_jinlmao@quicinc.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250226064008.2531037-3-quic_jinlmao@quicinc.com
MCMB (Multi-lane CMB) is a special form of CMB dataset type. MCMB
subunit TPDM has the same number and usage of registers as CMB
subunit TPDM. MCMB subunit can be enabled for data collection by
writing 1 to the first bit of CMB_CR register. The difference is
that MCMB subunit TPDM needs to select the lane and enable it in
using it.
Signed-off-by: Tao Zhang <quic_taozha@quicinc.com>
Signed-off-by: Mao Jinlong <quic_jinlmao@quicinc.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250226064008.2531037-2-quic_jinlmao@quicinc.com
As recommended by section 4.3.7 ("Synchronization when using system
instructions to progrom the trace unit") of ARM IHI 0064H.b, the
self-hosted trace analyzer must perform a Context synchronization
event between writing to the TRCPRGCTLR and reading the TRCSTATR.
Additionally, add an ISB between the each read of TRCSTATR on
coresight_timeout() when using system instructions to program the
trace unit.
Fixes: 1ab3bb9df5 ("coresight: etm4x: Add necessary synchronization for sysreg access")
Signed-off-by: Yuanfang Zhang <quic_yuanfang@quicinc.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250116-etm_sync-v4-1-39f2b05e9514@quicinc.com
The header clearly states that it does not want to be included directly,
only via '<linux/(platform_)?device.h>'. Which is already present, so
delete the superfluous include.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250210113635.51935-2-wsa+renesas@sang-engineering.com
Add a preloaded configuration for generating
external trigger on address match. This can be
used by CTI and ETR blocks to stop trace capture
on kernel panic.
Kernel address for "panic" function is used as the
default trigger address.
This new configuration is available as,
/sys/kernel/config/cs-syscfg/configurations/panicstop
Signed-off-by: Linu Cherian <lcherian@marvell.com>
Reviewed-by: James Clark <james.clark@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250212114918.548431-8-lcherian@marvell.com
Configure TMC ETR and ETF to flush and stop trace capture
on FlIn event based on sysfs attribute,
/sys/bus/coresight/devices/tmc_etXn/stop_on_flush.
Signed-off-by: Linu Cherian <lcherian@marvell.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250212114918.548431-7-lcherian@marvell.com
* Add support for reading crashdata using special device files.
The special device files /dev/crash_tmc_xxx would be available
for read file operation only when the crash data is valid.
* User can read the crash data as below
For example, for reading crash data from tmc_etf sink
#dd if=/dev/crash_tmc_etfXX of=~/cstrace.bin
Signed-off-by: Anil Kumar Reddy <areddy3@marvell.com>
Signed-off-by: Tanmay Jagdale <tanmay@marvell.com>
Signed-off-by: Linu Cherian <lcherian@marvell.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250212114918.548431-6-lcherian@marvell.com
- Get reserved region from device tree node for metadata
- Define metadata format for TMC
- Add TMC ETR panic sync handler that syncs register snapshot
to metadata region
- Add TMC ETF panic sync handler that syncs register snapshot
to metadata region and internal SRAM to reserved trace buffer
region.
Signed-off-by: Linu Cherian <lcherian@marvell.com>
Reviewed-by: James Clark <james.clark@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250212114918.548431-5-lcherian@marvell.com
Panic callback handlers allows coresight device drivers to sync
relevant trace data and trace metadata to reserved memory
regions so that they can be retrieved later in the subsequent
boot or in the crashdump kernel.
Signed-off-by: Linu Cherian <lcherian@marvell.com>
Reviewed-by: James Clark <james.clark@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250212114918.548431-4-lcherian@marvell.com
Add support to use reserved memory for coresight ETR trace buffer.
Introduce a new ETR buffer mode called ETR_MODE_RESRV, which
becomes available when ETR device tree node is supplied with a valid
reserved memory region.
ETR_MODE_RESRV can be selected only by explicit user request.
$ echo resrv >/sys/bus/coresight/devices/tmc_etr<N>/buf_mode_preferred
Signed-off-by: Anil Kumar Reddy <areddy3@marvell.com>
Signed-off-by: Linu Cherian <lcherian@marvell.com>
Reviewed-by: James Clark <james.clark@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250212114918.548431-3-lcherian@marvell.com
memory-region 0: Reserved trace buffer memory
TMC ETR: When available, use this reserved memory region for
trace data capture. Same region is used for trace data
retention after a panic or watchdog reset.
TMC ETF: When available, use this reserved memory region for
trace data retention synced from internal SRAM after a panic or
watchdog reset.
memory-region 1: Reserved meta data memory
TMC ETR, ETF: When available, use this memory for register
snapshot retention synced from hardware registers after a panic
or watchdog reset.
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linu Cherian <lcherian@marvell.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250212114918.548431-2-lcherian@marvell.com
Trying to record a trace on kernel with 64k pages resulted in -ENOMEM.
This happens due to a bug in calculating the number of table pages, which
returns zero. Fix the issue by rounding up.
$ perf record --kcore -e cs_etm/@tmc_etr55,cycacc,branch_broadcast/k --per-thread taskset --cpu-list 1 dd if=/dev/zero of=/dev/null
failed to mmap with 12 (Cannot allocate memory)
Fixes: 8ed536b1e2 ("coresight: catu: Add support for scatter gather tables")
Signed-off-by: Ilkka Koskinen <ilkka@os.amperecomputing.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250109215348.5483-1-ilkka@os.amperecomputing.com
- Fix annoying logs when building tools in parallel
- Fix the Debian linux-headers package build again
- Fix the target triple detection for userspace programs on Clang
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Merge tag 'kbuild-fixes-v6.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild fixes from Masahiro Yamada:
- Fix annoying logs when building tools in parallel
- Fix the Debian linux-headers package build again
- Fix the target triple detection for userspace programs on Clang
* tag 'kbuild-fixes-v6.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
modpost: Fix a few typos in a comment
kbuild: userprogs: fix bitsize and target detection on clang
kbuild: fix linux-headers package build when $(CC) cannot link userspace
tools: fix annoying "mkdir -p ..." logs when building tools in parallel
Here is a driver core new api for 6.14-rc3 that is being added to allow
platform devices from stop being abused. It adds a new "faux_device"
structure and bus and api to allow almost a straight or simpler
conversion from platform devices that were not really a platform device.
It also comes with a binding for rust, with an example driver in rust
showing how it's used.
I'm adding this now so that the patches that convert the different
drivers and subsystems can all start flowing into linux-next now through
their different development trees, in time for 6.15-rc1. We have a
number that are already reviewed and tested, but adding those
conversions now doesn't seem right. For now, no one is using this, and
it passes all build tests from 0-day and linux-next, so all should be
good.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core api addition from Greg KH:
"Here is a driver core new api for 6.14-rc3 that is being added to
allow platform devices from stop being abused.
It adds a new 'faux_device' structure and bus and api to allow almost
a straight or simpler conversion from platform devices that were not
really a platform device. It also comes with a binding for rust, with
an example driver in rust showing how it's used.
I'm adding this now so that the patches that convert the different
drivers and subsystems can all start flowing into linux-next now
through their different development trees, in time for 6.15-rc1.
We have a number that are already reviewed and tested, but adding
those conversions now doesn't seem right. For now, no one is using
this, and it passes all build tests from 0-day and linux-next, so all
should be good"
* tag 'driver-core-6.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
rust/kernel: Add faux device bindings
driver core: add a faux bus for use when a simple device/bus is needed
Here are some small serial driver fixes for some reported problems for
6.14-rc3. Nothing major, just:
- sc16is7xx irq check fix
- 8250 fifo underflow fix
- serial_port and 8250 iotype fixes
Most of these have been in linux-next already, and all have passed 0-day
testing.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-6.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull serial driver fixes from Greg KH:
"Here are some small serial driver fixes for some reported problems.
Nothing major, just:
- sc16is7xx irq check fix
- 8250 fifo underflow fix
- serial_port and 8250 iotype fixes
Most of these have been in linux-next already, and all have passed
0-day testing"
* tag 'tty-6.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
serial: 8250: Fix fifo underflow on flush
serial: 8250_pnp: Remove unneeded ->iotype assignment
serial: 8250_platform: Remove unneeded ->iotype assignment
serial: 8250_of: Remove unneeded ->iotype assignment
serial: port: Make ->iotype validation global in __uart_read_properties()
serial: port: Always update ->iotype in __uart_read_properties()
serial: port: Assign ->iotype correctly when ->iobase is set
serial: sc16is7xx: Fix IRQ number check behavior
Here are some small USB driver fixes, and new device ids, for 6.14-rc3.
Lots of tiny stuff for reported problems, including:
- new device ids and quirks
- usb hub crash fix found by syzbot
- dwc2 driver fix
- dwc3 driver fixes
- uvc gadget driver fix
- cdc-acm driver fixes for a variety of different issues
- other tiny bugfixes
Almost all of these have been in linux-next this week, and all have
passed 0-day testing.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-6.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB fixes from Greg KH:
"Here are some small USB driver fixes, and new device ids, for
6.14-rc3. Lots of tiny stuff for reported problems, including:
- new device ids and quirks
- usb hub crash fix found by syzbot
- dwc2 driver fix
- dwc3 driver fixes
- uvc gadget driver fix
- cdc-acm driver fixes for a variety of different issues
- other tiny bugfixes
Almost all of these have been in linux-next this week, and all have
passed 0-day testing"
* tag 'usb-6.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (25 commits)
usb: typec: tcpm: PSSourceOffTimer timeout in PR_Swap enters ERROR_RECOVERY
usb: roles: set switch registered flag early on
usb: gadget: uvc: Fix unstarted kthread worker
USB: quirks: add USB_QUIRK_NO_LPM quirk for Teclast dist
usb: gadget: core: flush gadget workqueue after device removal
USB: gadget: f_midi: f_midi_complete to call queue_work
usb: core: fix pipe creation for get_bMaxPacketSize0
usb: dwc3: Fix timeout issue during controller enter/exit from halt state
USB: Add USB_QUIRK_NO_LPM quirk for sony xperia xz1 smartphone
USB: cdc-acm: Fill in Renesas R-Car D3 USB Download mode quirk
usb: cdc-acm: Fix handling of oversized fragments
usb: cdc-acm: Check control transfer buffer size before access
usb: xhci: Restore xhci_pci support for Renesas HCs
USB: pci-quirks: Fix HCCPARAMS register error for LS7A EHCI
USB: serial: option: drop MeiG Smart defines
USB: serial: option: fix Telit Cinterion FN990A name
USB: serial: option: add Telit Cinterion FN990B compositions
USB: serial: option: add MeiG Smart SLM828
usb: gadget: f_midi: fix MIDI Streaming descriptor lengths
usb: dwc2: gadget: remove of_node reference upon udc_stop
...
handoff to the OS
- Check CPUID(0x23) leaf and subleafs presence properly
- Remove the PEBS-via-PT feature from being supported on hybrid systems
- Fix perf record/top default commands on systems without a raw PMU registered
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Merge tag 'perf_urgent_for_v6.14_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 perf fixes from Borislav Petkov:
- Explicitly clear DEBUGCTL.LBR to prevent LBRs continuing being
enabled after handoff to the OS
- Check CPUID(0x23) leaf and subleafs presence properly
- Remove the PEBS-via-PT feature from being supported on hybrid systems
- Fix perf record/top default commands on systems without a raw PMU
registered
* tag 'perf_urgent_for_v6.14_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel: Ensure LBRs are disabled when a CPU is starting
perf/x86/intel: Fix ARCH_PERFMON_NUM_COUNTER_LEAF
perf/x86/intel: Clean up PEBS-via-PT on hybrid
perf/x86/rapl: Fix the error checking order
clear its removal from that queue is atomic
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Merge tag 'sched_urgent_for_v6.14_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fix from Borislav Petkov:
- Clarify what happens when a task is woken up from the wake queue and
make clear its removal from that queue is atomic
* tag 'sched_urgent_for_v6.14_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched: Clarify wake_up_q()'s write to task->wake_q.next
breakage has been fixed in the meantime
- Teach objtool to ignore dangling jump table entries added by Clang
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Merge tag 'objtool_urgent_for_v6.14_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool fixes from Borislav Petkov:
- Move a warning about a lld.ld breakage into the verbose setting as
said breakage has been fixed in the meantime
- Teach objtool to ignore dangling jump table entries added by Clang
* tag 'objtool_urgent_for_v6.14_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
objtool: Move dodgy linker warn to verbose
objtool: Ignore dangling jump table entries
- Large set of fixes for vector handling, specially in the interactions
between host and guest state. This fixes a number of bugs affecting
actual deployments, and greatly simplifies the FP/SIMD/SVE handling.
Thanks to Mark Rutland for dealing with this thankless task.
- Fix an ugly race between vcpu and vgic creation/init, resulting in
unexpected behaviours.
- Fix use of kernel VAs at EL2 when emulating timers with nVHE.
- Small set of pKVM improvements and cleanups.
x86:
- Fix broken SNP support with KVM module built-in, ensuring the PSP
module is initialized before KVM even when the module infrastructure
cannot be used to order initcalls
- Reject Hyper-V SEND_IPI hypercalls if the local APIC isn't being emulated
by KVM to fix a NULL pointer dereference.
- Enter guest mode (L2) from KVM's perspective before initializing the vCPU's
nested NPT MMU so that the MMU is properly tagged for L2, not L1.
- Load the guest's DR6 outside of the innermost .vcpu_run() loop, as the
guest's value may be stale if a VM-Exit is handled in the fastpath.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini:
"ARM:
- Large set of fixes for vector handling, especially in the
interactions between host and guest state.
This fixes a number of bugs affecting actual deployments, and
greatly simplifies the FP/SIMD/SVE handling. Thanks to Mark Rutland
for dealing with this thankless task.
- Fix an ugly race between vcpu and vgic creation/init, resulting in
unexpected behaviours
- Fix use of kernel VAs at EL2 when emulating timers with nVHE
- Small set of pKVM improvements and cleanups
x86:
- Fix broken SNP support with KVM module built-in, ensuring the PSP
module is initialized before KVM even when the module
infrastructure cannot be used to order initcalls
- Reject Hyper-V SEND_IPI hypercalls if the local APIC isn't being
emulated by KVM to fix a NULL pointer dereference
- Enter guest mode (L2) from KVM's perspective before initializing
the vCPU's nested NPT MMU so that the MMU is properly tagged for
L2, not L1
- Load the guest's DR6 outside of the innermost .vcpu_run() loop, as
the guest's value may be stale if a VM-Exit is handled in the
fastpath"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (25 commits)
x86/sev: Fix broken SNP support with KVM module built-in
KVM: SVM: Ensure PSP module is initialized if KVM module is built-in
crypto: ccp: Add external API interface for PSP module initialization
KVM: arm64: vgic: Hoist SGI/PPI alloc from vgic_init() to kvm_create_vgic()
KVM: arm64: timer: Drop warning on failed interrupt signalling
KVM: arm64: Fix alignment of kvm_hyp_memcache allocations
KVM: arm64: Convert timer offset VA when accessed in HYP code
KVM: arm64: Simplify warning in kvm_arch_vcpu_load_fp()
KVM: arm64: Eagerly switch ZCR_EL{1,2}
KVM: arm64: Mark some header functions as inline
KVM: arm64: Refactor exit handlers
KVM: arm64: Refactor CPTR trap deactivation
KVM: arm64: Remove VHE host restore of CPACR_EL1.SMEN
KVM: arm64: Remove VHE host restore of CPACR_EL1.ZEN
KVM: arm64: Remove host FPSIMD saving for non-protected KVM
KVM: arm64: Unconditionally save+flush host FPSIMD/SVE/SME state
KVM: x86: Load DR6 with guest value only before entering .vcpu_run() loop
KVM: nSVM: Enter guest mode before initializing nested NPT MMU
KVM: selftests: Add CPUID tests for Hyper-V features that need in-kernel APIC
KVM: selftests: Manage CPUID array in Hyper-V CPUID test's core helper
...
- Align signal stack correctly
- Convert to raw spinlocks where needed (irq and virtio)
- FPU related fixes
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Merge tag 'uml-for-linus-6.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux
Pull UML fixes from Richard Weinberger:
- Align signal stack correctly
- Convert to raw spinlocks where needed (irq and virtio)
- FPU related fixes
* tag 'uml-for-linus-6.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux:
um: convert irq_lock to raw spinlock
um: virtio_uml: use raw spinlock
um: virt-pci: don't use kmalloc()
um: fix execve stub execution on old host OSs
um: properly align signal stack on x86_64
um: avoid copying FP state from init_task
um: add back support for FXSAVE registers
- Enable resize on mmap() error
When a process mmaps a ring buffer, its size is locked and resizing is
disabled. But if the user passes in a wrong parameter, the mmap() can fail
after the resize was disabled and the mmap() exits with error without
reenabling the ring buffer resize. This prevents the ring buffer from ever
being resized after that. Reenable resizing of the ring buffer on mmap()
error.
- Have resizing return proper error and not always -ENOMEM
If the ring buffer is mmapped by one task and another task tries to resize
the buffer it will error with -ENOMEM. This is confusing to the user as
there may be plenty of memory available. Have it return the error that
actually happens (in this case -EBUSY) where the user can understand why
the resize failed.
- Test the sub-buffer array to validate persistent memory buffer
On boot up, the initialization of the persistent memory buffer will do a
validation check to see if the content of the data is valid, and if so, it
will use the memory as is, otherwise it re-initializes it. There's meta
data in this persistent memory that keeps track of which sub-buffer is the
reader page and an array that states the order of the sub-buffers. The
values in this array are indexes into the sub-buffers. The validator
checks to make sure that all the entries in the array are within the
sub-buffer list index, but it does not check for duplications.
While working on this code, the array got corrupted and had duplicates,
where not all the sub-buffers were accounted for. This passed the
validator as all entries were valid, but the link list was incorrect and
could have caused a crash. The corruption only produced incorrect data,
but it could have been more severe. To fix this, create a bitmask that
covers all the sub-buffer indexes and set it to all zeros. While iterating
the array checking the values of the array content, have it set a bit
corresponding to the index in the array. If the bit was already set, then
it is a duplicate and mark the buffer as invalid and reset it.
- Prevent mmap()ing persistent ring buffer
The persistent ring buffer uses vmap() to map the persistent memory.
Currently, the mmap() logic only uses virt_to_page() to get the page
from the ring buffer memory and use that to map to user space. This works
because a normal ring buffer uses alloc_page() to allocate its memory.
But because the persistent ring buffer use vmap() it causes a kernel
crash. Fixing this to work with vmap() is not hard, but since mmap() on
persistent memory buffers never worked, just have the mmap() return
-ENODEV (what was returned before mmap() for persistent memory ring
buffers, as they never supported mmap. Normal buffers will still allow
mmap(). Implementing mmap() for persistent memory ring buffers can wait
till the next merge window.
- Fix polling on persistent ring buffers
There's a "buffer_percent" option (default set to 50), that is used to
have reads of the ring buffer binary data block until the buffer fills to
that percentage. The field "pages_touched" is incremented every time a
new sub-buffer has content added to it. This field is used in the
calculations to determine the amount of content is in the buffer and if it
exceeds the "buffer_percent" then it will wake the task polling on the
buffer.
As persistent ring buffers can be created by the content from a previous
boot, the "pages_touched" field was not updated. This means that if a task
were to poll on the persistent buffer, it would block even if the buffer
was completely full. It would block even if the "buffer_percent" was zero,
because with "pages_touched" as zero, it would be calculated as the buffer
having no content. Update pages_touched when initializing the persistent
ring buffer from a previous boot.
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Merge tag 'trace-ring-buffer-v6.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull trace ring buffer fixes from Steven Rostedt:
- Enable resize on mmap() error
When a process mmaps a ring buffer, its size is locked and resizing
is disabled. But if the user passes in a wrong parameter, the mmap()
can fail after the resize was disabled and the mmap() exits with
error without reenabling the ring buffer resize. This prevents the
ring buffer from ever being resized after that. Reenable resizing of
the ring buffer on mmap() error.
- Have resizing return proper error and not always -ENOMEM
If the ring buffer is mmapped by one task and another task tries to
resize the buffer it will error with -ENOMEM. This is confusing to
the user as there may be plenty of memory available. Have it return
the error that actually happens (in this case -EBUSY) where the user
can understand why the resize failed.
- Test the sub-buffer array to validate persistent memory buffer
On boot up, the initialization of the persistent memory buffer will
do a validation check to see if the content of the data is valid, and
if so, it will use the memory as is, otherwise it re-initializes it.
There's meta data in this persistent memory that keeps track of which
sub-buffer is the reader page and an array that states the order of
the sub-buffers. The values in this array are indexes into the
sub-buffers. The validator checks to make sure that all the entries
in the array are within the sub-buffer list index, but it does not
check for duplications.
While working on this code, the array got corrupted and had
duplicates, where not all the sub-buffers were accounted for. This
passed the validator as all entries were valid, but the link list was
incorrect and could have caused a crash. The corruption only produced
incorrect data, but it could have been more severe. To fix this,
create a bitmask that covers all the sub-buffer indexes and set it to
all zeros. While iterating the array checking the values of the array
content, have it set a bit corresponding to the index in the array.
If the bit was already set, then it is a duplicate and mark the
buffer as invalid and reset it.
- Prevent mmap()ing persistent ring buffer
The persistent ring buffer uses vmap() to map the persistent memory.
Currently, the mmap() logic only uses virt_to_page() to get the page
from the ring buffer memory and use that to map to user space. This
works because a normal ring buffer uses alloc_page() to allocate its
memory. But because the persistent ring buffer use vmap() it causes a
kernel crash.
Fixing this to work with vmap() is not hard, but since mmap() on
persistent memory buffers never worked, just have the mmap() return
-ENODEV (what was returned before mmap() for persistent memory ring
buffers, as they never supported mmap. Normal buffers will still
allow mmap(). Implementing mmap() for persistent memory ring buffers
can wait till the next merge window.
- Fix polling on persistent ring buffers
There's a "buffer_percent" option (default set to 50), that is used
to have reads of the ring buffer binary data block until the buffer
fills to that percentage. The field "pages_touched" is incremented
every time a new sub-buffer has content added to it. This field is
used in the calculations to determine the amount of content is in the
buffer and if it exceeds the "buffer_percent" then it will wake the
task polling on the buffer.
As persistent ring buffers can be created by the content from a
previous boot, the "pages_touched" field was not updated. This means
that if a task were to poll on the persistent buffer, it would block
even if the buffer was completely full. It would block even if the
"buffer_percent" was zero, because with "pages_touched" as zero, it
would be calculated as the buffer having no content. Update
pages_touched when initializing the persistent ring buffer from a
previous boot.
* tag 'trace-ring-buffer-v6.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
ring-buffer: Update pages_touched to reflect persistent buffer content
tracing: Do not allow mmap() of persistent ring buffer
ring-buffer: Validate the persistent meta data subbuf array
tracing: Have the error of __tracing_resize_ring_buffer() passed to user
ring-buffer: Unlock resize on mmap error
The pages_touched field represents the number of subbuffers in the ring
buffer that have content that can be read. This is used in accounting of
"dirty_pages" and "buffer_percent" to allow the user to wait for the
buffer to be filled to a certain amount before it reads the buffer in
blocking mode.
The persistent buffer never updated this value so it was set to zero, and
this accounting would take it as it had no content. This would cause user
space to wait for content even though there's enough content in the ring
buffer that satisfies the buffer_percent.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/20250214123512.0631436e@gandalf.local.home
Fixes: 5f3b6e839f ("ring-buffer: Validate boot range memory events")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
