Linux kernel
============
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In order to build the documentation, use ``make htmldocs`` or
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https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
code
Clone this repository
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Pull USB / Thunderbolt driver fixes from Greg KH:
"Here are a small set of USB and Thunderbolt driver fixes for reported
problems and a documentation update, for 6.3-rc4.
Included in here are:
- documentation update for uvc gadget driver
- small thunderbolt driver fixes
- cdns3 driver fixes
- dwc3 driver fixes
- dwc2 driver fixes
- chipidea driver fixes
- typec driver fixes
- onboard_usb_hub device id updates
- quirk updates
All of these have been in linux-next with no reported problems"
* tag 'usb-6.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (30 commits)
usb: dwc2: fix a race, don't power off/on phy for dual-role mode
usb: dwc2: fix a devres leak in hw_enable upon suspend resume
usb: chipidea: core: fix possible concurrent when switch role
usb: chipdea: core: fix return -EINVAL if request role is the same with current role
thunderbolt: Rename shadowed variables bit to interrupt_bit and auto_clear_bit
thunderbolt: Disable interrupt auto clear for rings
thunderbolt: Use const qualifier for `ring_interrupt_index`
usb: gadget: Use correct endianness of the wLength field for WebUSB
uas: Add US_FL_NO_REPORT_OPCODES for JMicron JMS583Gen 2
usb: cdnsp: changes PCI Device ID to fix conflict with CNDS3 driver
usb: cdns3: Fix issue with using incorrect PCI device function
usb: cdnsp: Fixes issue with redundant Status Stage
MAINTAINERS: make me a reviewer of USB/IP
thunderbolt: Use scale field when allocating USB3 bandwidth
thunderbolt: Limit USB3 bandwidth of certain Intel USB4 host routers
thunderbolt: Call tb_check_quirks() after initializing adapters
thunderbolt: Add missing UNSET_INBOUND_SBTX for retimer access
thunderbolt: Fix memory leak in margining
usb: dwc2: drd: fix inconsistent mode if role-switch-default-mode="host"
docs: usb: Add documentation for the UVC Gadget
...
Pull scheduler fix from Borislav Petkov:
- Fix a corner case where vruntime of a task is not being sanitized
* tag 'sched_urgent_for_v6.3_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Sanitize vruntime of entity being migrated
When in dual role mode (dr_mode == USB_DR_MODE_OTG), platform probe
successively basically calls:
- dwc2_gadget_init()
- dwc2_hcd_init()
- dwc2_lowlevel_hw_disable() since recent change [1]
- usb_add_gadget_udc()
The PHYs (and so the clocks it may provide) shouldn't be disabled for all
SoCs, in OTG mode, as the HCD part has been initialized.
On STM32 this creates some weird race condition upon boot, when:
- initially attached as a device, to a HOST
- and there is a gadget script invoked to setup the device part.
Below issue becomes systematic, as long as the gadget script isn't
started by userland: the hardware PHYs (and so the clocks provided by the
PHYs) remains disabled.
It ends up in having an endless interrupt storm, before the watchdog
resets the platform.
[ 16.924163] dwc2 49000000.usb-otg: EPs: 9, dedicated fifos, 952 entries in SPRAM
[ 16.962704] dwc2 49000000.usb-otg: DWC OTG Controller
[ 16.966488] dwc2 49000000.usb-otg: new USB bus registered, assigned bus number 2
[ 16.974051] dwc2 49000000.usb-otg: irq 77, io mem 0x49000000
[ 17.032170] hub 2-0:1.0: USB hub found
[ 17.042299] hub 2-0:1.0: 1 port detected
[ 17.175408] dwc2 49000000.usb-otg: Mode Mismatch Interrupt: currently in Host mode
[ 17.181741] dwc2 49000000.usb-otg: Mode Mismatch Interrupt: currently in Host mode
[ 17.189303] dwc2 49000000.usb-otg: Mode Mismatch Interrupt: currently in Host mode
...
The host part is also not functional, until the gadget part is configured.
The HW may only be disabled for peripheral mode (original init), e.g.
dr_mode == USB_DR_MODE_PERIPHERAL, until the gadget driver initializes.
But when in USB_DR_MODE_OTG, the HW should remain enabled, as the HCD part
is able to run, while the gadget part isn't necessarily configured.
I don't fully get the of purpose the original change, that claims disabling
the hardware is missing. It creates conditions on SOCs using the PHY
initialization to be completely non working in OTG mode. Original
change [1] should be reworked to be platform specific.
[1] https://lore.kernel.org/r/20221206-dwc2-gadget-dual-role-v1-2-36515e1092cd@theobroma-systems.com
Fixes: ade23d7b7ec5 ("usb: dwc2: power on/off phy for peripheral mode in dual-role mode")
Cc: stable <stable@kernel.org>
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Reviewed-by: Quentin Schulz <quentin.schulz@theobroma-systems.com>
Tested-by: Quentin Schulz <quentin.schulz@theobroma-systems.com>
Link: https://lore.kernel.org/r/20230315144433.3095859-1-fabrice.gasnier@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull perf fix from Borislav Petkov:
- Properly clear perf event status tracking in the AMD perf event
overflow handler
* tag 'perf_urgent_for_v6.3_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/amd/core: Always clear status for idx
Commit 829c1651e9c4 ("sched/fair: sanitize vruntime of entity being placed")
fixes an overflowing bug, but ignore a case that se->exec_start is reset
after a migration.
For fixing this case, we delay the reset of se->exec_start after
placing the entity which se->exec_start to detect long sleeping task.
In order to take into account a possible divergence between the clock_task
of 2 rqs, we increase the threshold to around 104 days.
Fixes: 829c1651e9c4 ("sched/fair: sanitize vruntime of entity being placed")
Originally-by: Zhang Qiao <zhangqiao22@huawei.com>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Qiao <zhangqiao22@huawei.com>
Link: https://lore.kernel.org/r/20230317160810.107988-1-vincent.guittot@linaro.org
Each time the platform goes to low power, PM suspend / resume routines
call: __dwc2_lowlevel_hw_enable -> devm_add_action_or_reset().
This adds a new devres each time.
This may also happen at runtime, as dwc2_lowlevel_hw_enable() can be
called from udc_start().
This can be seen with tracing:
- echo 1 > /sys/kernel/debug/tracing/events/dev/devres_log/enable
- go to low power
- cat /sys/kernel/debug/tracing/trace
A new "ADD" entry is found upon each low power cycle:
... devres_log: 49000000.usb-otg ADD 82a13bba devm_action_release (8 bytes)
... devres_log: 49000000.usb-otg ADD 49889daf devm_action_release (8 bytes)
...
A second issue is addressed here:
- regulator_bulk_enable() is called upon each PM cycle (suspend/resume).
- regulator_bulk_disable() never gets called.
So the reference count for these regulators constantly increase, by one
upon each low power cycle, due to missing regulator_bulk_disable() call
in __dwc2_lowlevel_hw_disable().
The original fix that introduced the devm_add_action_or_reset() call,
fixed an issue during probe, that happens due to other errors in
dwc2_driver_probe() -> dwc2_core_reset(). Then the probe fails without
disabling regulators, when dr_mode == USB_DR_MODE_PERIPHERAL.
Rather fix the error path: disable all the low level hardware in the
error path, by using the "hsotg->ll_hw_enabled" flag. Checking dr_mode
has been introduced to avoid a dual call to dwc2_lowlevel_hw_disable().
"ll_hw_enabled" should achieve the same (and is used currently in the
remove() routine).
Fixes: 54c196060510 ("usb: dwc2: Always disable regulators on driver teardown")
Fixes: 33a06f1300a7 ("usb: dwc2: Fix error path in gadget registration")
Cc: stable <stable@kernel.org>
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Link: https://lore.kernel.org/r/20230316084127.126084-1-fabrice.gasnier@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull core fixes from Borislav Petkov:
- Do the delayed RCU wakeup for kthreads in the proper order so that
former doesn't get ignored
- A noinstr warning fix
* tag 'core_urgent_for_v6.3_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
entry/rcu: Check TIF_RESCHED _after_ delayed RCU wake-up
entry: Fix noinstr warning in __enter_from_user_mode()
The variable 'status' (which contains the unhandled overflow bits) is
not being properly masked in some cases, displaying the following
warning:
WARNING: CPU: 156 PID: 475601 at arch/x86/events/amd/core.c:972 amd_pmu_v2_handle_irq+0x216/0x270
This seems to be happening because the loop is being continued before
the status bit being unset, in case x86_perf_event_set_period()
returns 0. This is also causing an inconsistency because the "handled"
counter is incremented, but the status bit is not cleaned.
Move the bit cleaning together above, together when the "handled"
counter is incremented.
Fixes: 7685665c390d ("perf/x86/amd/core: Add PerfMonV2 overflow handling")
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Sandipan Das <sandipan.das@amd.com>
Link: https://lore.kernel.org/r/20230321113338.1669660-1-leitao@debian.org
The user may call role_store() when driver is handling
ci_handle_id_switch() which is triggerred by otg event or power lost
event. Unfortunately, the controller may go into chaos in this case.
Fix this by protecting it with mutex lock.
Fixes: a932a8041ff9 ("usb: chipidea: core: add sysfs group")
cc: <stable@vger.kernel.org>
Acked-by: Peter Chen <peter.chen@kernel.org>
Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
Link: https://lore.kernel.org/r/20230317061516.2451728-2-xu.yang_2@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull x86 fixes from Borislav Petkov:
- Add a AMX ptrace self test
- Prevent a false-positive warning when retrieving the (invalid)
address of dynamic FPU features in their init state which are not
saved in init_fpstate at all
- Randomize per-CPU entry areas only when KASLR is enabled
* tag 'x86_urgent_for_v6.3_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
selftests/x86/amx: Add a ptrace test
x86/fpu/xstate: Prevent false-positive warning in __copy_xstate_uabi_buf()
x86/mm: Do not shuffle CPU entry areas without KASLR
RCU sometimes needs to perform a delayed wake up for specific kthreads
handling offloaded callbacks (RCU_NOCB). These wakeups are performed
by timers and upon entry to idle (also to guest and to user on nohz_full).
However the delayed wake-up on kernel exit is actually performed after
the thread flags are fetched towards the fast path check for work to
do on exit to user. As a result, and if there is no other pending work
to do upon that kernel exit, the current task will resume to userspace
with TIF_RESCHED set and the pending wake up ignored.
Fix this with fetching the thread flags _after_ the delayed RCU-nocb
kthread wake-up.
Fixes: 47b8ff194c1f ("entry: Explicitly flush pending rcuog wakeup before last rescheduling point")
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230315194349.10798-3-joel@joelfernandes.org
Pull tracing fixes from Steven Rostedt:
- Fix setting affinity of hwlat threads in containers
Using sched_set_affinity() has unwanted side effects when being
called within a container. Use set_cpus_allowed_ptr() instead
- Fix per cpu thread management of the hwlat tracer:
- Do not start per_cpu threads if one is already running for the CPU
- When starting per_cpu threads, do not clear the kthread variable
as it may already be set to running per cpu threads
- Fix return value for test_gen_kprobe_cmd()
On error the return value was overwritten by being set to the result
of the call from kprobe_event_delete(), which would likely succeed,
and thus have the function return success
- Fix splice() reads from the trace file that was broken by commit
36e2c7421f02 ("fs: don't allow splice read/write without explicit
ops")
- Remove obsolete and confusing comment in ring_buffer.c
The original design of the ring buffer used struct page flags for
tricks to optimize, which was shortly removed due to them being
tricks. But a comment for those tricks remained
- Set local functions and variables to static
* tag 'trace-v6.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing/hwlat: Replace sched_setaffinity with set_cpus_allowed_ptr
ring-buffer: remove obsolete comment for free_buffer_page()
tracing: Make splice_read available again
ftrace: Set direct_ops storage-class-specifier to static
trace/hwlat: Do not start per-cpu thread if it is already running
trace/hwlat: Do not wipe the contents of per-cpu thread data
tracing/osnoise: set several trace_osnoise.c variables storage-class-specifier to static
tracing: Fix wrong return in kprobe_event_gen_test.c
It should not return -EINVAL if the request role is the same with current
role, return non-error and without do anything instead.
Fixes: a932a8041ff9 ("usb: chipidea: core: add sysfs group")
cc: <stable@vger.kernel.org>
Acked-by: Peter Chen <peter.chen@kernel.org>
Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
Link: https://lore.kernel.org/r/20230317061516.2451728-1-xu.yang_2@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull cifs client fixes from Steve French:
"Twelve cifs/smb3 client fixes (most also for stable)
- forced umount fix
- fix for two perf regressions
- reconnect fixes
- small debugging improvements
- multichannel fixes"
* tag 'smb3-client-fixes-6.3-rc3' of git://git.samba.org/sfrench/cifs-2.6:
smb3: fix unusable share after force unmount failure
cifs: fix dentry lookups in directory handle cache
smb3: lower default deferred close timeout to address perf regression
cifs: fix missing unload_nls() in smb2_reconnect()
cifs: avoid race conditions with parallel reconnects
cifs: append path to open_enter trace event
cifs: print session id while listing open files
cifs: dump pending mids for all channels in DebugData
cifs: empty interface list when server doesn't support query interfaces
cifs: do not poll server interfaces too regularly
cifs: lock chan_lock outside match_session
cifs: check only tcon status on tcon related functions