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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
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
Namely: s/becasue/because/ and s/wiht/with/ plus an added article.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
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
This introduces a module for working with faux devices in rust, along with
adding sample code to show how the API is used. Unlike other types of
devices, we don't provide any hooks for device probe/removal - since these
are optional for the faux API and are unnecessary in rust.
Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: Maíra Canal <mairacanal@riseup.net>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/2025021026-exert-accent-b4c6@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
scripts/Makefile.clang was changed in the linked commit to move --target from
KBUILD_CFLAGS to KBUILD_CPPFLAGS, as that generally has a broader scope.
However that variable is not inspected by the userprogs logic,
breaking cross compilation on clang.
Use both variables to detect bitsize and target arguments for userprogs.
Fixes: feb843a469fb ("kbuild: add $(CLANG_FLAGS) to KBUILD_CPPFLAGS")
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
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
...
When flushing the serial port's buffer, uart_flush_buffer() calls
kfifo_reset() but if there is an outstanding DMA transfer then the
completion function will consume data from the kfifo via
uart_xmit_advance(), underflowing and leading to ongoing DMA as the
driver tries to transmit another 2^32 bytes.
This is readily reproduced with serial-generic and amidi sending even
short messages as closing the device on exit will wait for the fifo to
drain and in the underflow case amidi hangs for 30 seconds on exit in
tty_wait_until_sent(). A trace of that gives:
kworker/1:1-84 [001] 51.769423: bprint: serial8250_tx_dma: tx_size=3 fifo_len=3
amidi-763 [001] 51.769460: bprint: uart_flush_buffer: resetting fifo
irq/21-fe530000-76 [000] 51.769474: bprint: __dma_tx_complete: tx_size=3
irq/21-fe530000-76 [000] 51.769479: bprint: serial8250_tx_dma: tx_size=4096 fifo_len=4294967293
irq/21-fe530000-76 [000] 51.781295: bprint: __dma_tx_complete: tx_size=4096
irq/21-fe530000-76 [000] 51.781301: bprint: serial8250_tx_dma: tx_size=4096 fifo_len=4294963197
irq/21-fe530000-76 [000] 51.793131: bprint: __dma_tx_complete: tx_size=4096
irq/21-fe530000-76 [000] 51.793135: bprint: serial8250_tx_dma: tx_size=4096 fifo_len=4294959101
irq/21-fe530000-76 [000] 51.804949: bprint: __dma_tx_complete: tx_size=4096
Since the port lock is held in when the kfifo is reset in
uart_flush_buffer() and in __dma_tx_complete(), adding a flush_buffer
hook to adjust the outstanding DMA byte count is sufficient to avoid the
kfifo underflow.
Fixes: 9ee4b83e51f74 ("serial: 8250: Add support for dmaengine")
Cc: stable <stable@kernel.org>
Signed-off-by: John Keeping <jkeeping@inmusicbrands.com>
Link: https://lore.kernel.org/r/20250208124148.1189191-1-jkeeping@inmusicbrands.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Many drivers abuse the platform driver/bus system as it provides a
simple way to create and bind a device to a driver-specific set of
probe/release functions. Instead of doing that, and wasting all of the
memory associated with a platform device, here is a "faux" bus that
can be used instead.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Zijun Hu <quic_zijuhu@quicinc.com>
Link: https://lore.kernel.org/r/2025021026-atlantic-gibberish-3f0c@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since commit 5f73e7d0386d ("kbuild: refactor cross-compiling
linux-headers package"), the linux-headers Debian package fails to
build when $(CC) cannot build userspace applications, for example,
when using toolchains installed by the 0day bot.
The host programs in the linux-headers package should be rebuilt using
the disto's cross-compiler, ${DEB_HOST_GNU_TYPE}-gcc instead of $(CC).
Hence, the variable 'CC' must be expanded in this shell script instead
of in the top-level Makefile.
Commit f354fc88a72a ("kbuild: install-extmod-build: add missing
quotation marks for CC variable") was not a correct fix because
CC="ccache gcc" should be unrelated when rebuilding userspace tools.
Fixes: 5f73e7d0386d ("kbuild: refactor cross-compiling linux-headers package")
Reported-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
Closes: https://lore.kernel.org/linux-kbuild/CAK7LNARb3xO3ptBWOMpwKcyf3=zkfhMey5H2KnB1dOmUwM79dA@mail.gmail.com/T/#t
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
Pull irq Kconfig cleanup from Borislav Petkov:
- Remove an unused config item GENERIC_PENDING_IRQ_CHIPFLAGS
* tag 'irq_urgent_for_v6.14_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq: Remove unused CONFIG_GENERIC_PENDING_IRQ_CHIPFLAGS
As PD2.0 spec ("6.5.6.2 PSSourceOffTimer")，the PSSourceOffTimer is
used by the Policy Engine in Dual-Role Power device that is currently
acting as a Sink to timeout on a PS_RDY Message during a Power Role
Swap sequence. This condition leads to a Hard Reset for USB Type-A and
Type-B Plugs and Error Recovery for Type-C plugs and return to USB
Default Operation.
Therefore, after PSSourceOffTimer timeout, the tcpm state machine should
switch from PR_SWAP_SNK_SRC_SINK_OFF to ERROR_RECOVERY. This can also
solve the test items in the USB power delivery compliance test:
TEST.PD.PROT.SNK.12 PR_Swap – PSSourceOffTimer Timeout
[1] https://usb.org/document-library/usb-power-delivery-compliance-test-specification-0/USB_PD3_CTS_Q4_2025_OR.zip
Fixes: f0690a25a140 ("staging: typec: USB Type-C Port Manager (tcpm)")
Cc: stable <stable@kernel.org>
Signed-off-by: Jos Wang <joswang@lenovo.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Tested-by: Amit Sunil Dhamne <amitsd@google.com>
Link: https://lore.kernel.org/r/20250213134921.3798-1-joswang1221@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If ->iobase is set the default will be UPIO_PORT for ->iotype after
the uart_read_and_validate_port_properties() call. Hence no need
to assign that explicitly. Otherwise it will be UPIO_MEM.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20250124161530.398361-7-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When CONFIG_OBJTOOL=y or CONFIG_DEBUG_INFO_BTF=y, parallel builds
show awkward "mkdir -p ..." logs.
$ make -j16
[ snip ]
mkdir -p /home/masahiro/ref/linux/tools/objtool && make O=/home/masahiro/ref/linux subdir=tools/objtool --no-print-directory -C objtool
mkdir -p /home/masahiro/ref/linux/tools/bpf/resolve_btfids && make O=/home/masahiro/ref/linux subdir=tools/bpf/resolve_btfids --no-print-directory -C bpf/resolve_btfids
Defining MAKEFLAGS=<value> on the command line wipes out command line
switches from the resultant MAKEFLAGS definition, even though the command
line switches are active. [1]
MAKEFLAGS puts all single-letter options into the first word, and that
word will be empty if no single-letter options were given. [2]
However, this breaks if MAKEFLAGS=<value> is given on the command line.
The tools/ and tools/% targets set MAKEFLAGS=<value> on the command
line, which breaks the following code in tools/scripts/Makefile.include:
short-opts := $(firstword -$(MAKEFLAGS))
If MAKEFLAGS really needs modification, it should be done through the
environment variable, as follows:
MAKEFLAGS=<value> $(MAKE) ...
That said, I question whether modifying MAKEFLAGS is necessary here.
The only flag we might want to exclude is --no-print-directory, as the
tools build system changes the working directory. However, people might
find the "Entering/Leaving directory" logs annoying.
I simply removed the offending MAKEFLAGS=<value>.
[1]: https://savannah.gnu.org/bugs/?62469
[2]: https://www.gnu.org/software/make/manual/make.html#Testing-Flags
Fixes: ea01fa9f63ae ("tools: Connect to the kernel build system")
Fixes: a50e43332756 ("perf tools: Honor parallel jobs")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Daniel Xu <dxu@dxuuu.xyz>
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
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