Initialize hs_settle to 0 to avoid this compiler warning:
imx8mq-mipi-csi2.c: In function 'imx8mq_mipi_csi_start_stream.part.0':
imx8mq-mipi-csi2.c:91:55: warning: 'hs_settle' may be used uninitialized [-Wmaybe-uninitialized]
91 | #define GPR_CSI2_1_S_PRG_RXHS_SETTLE(x) (((x) & 0x3f) << 2)
| ^~
imx8mq-mipi-csi2.c:357:13: note: 'hs_settle' was declared here
357 | u32 hs_settle;
| ^~~~~~~~~
It's a false positive, but it is too complicated for the compiler to detect that.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reviewed-by: Martin Kepplinger <martink@posteo.de>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
While updating v4l2_create_fwnode_links_to_pad() to accept non-subdev
sinks, the check is_media_entity_v4l2_subdev() was not removed which
prevented the function from being used with non-subdev sinks, Drop the
unnecessary check.
Fixes: bd5a03bc5b ("media: Accept non-subdev sinks in v4l2_create_fwnode_links_to_pad()")
Signed-off-by: Vaishnav Achath <vaishnav.a@ti.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
In the event of a change in XGBE mode, the current auto-negotiation
needs to be reset and the AN cycle needs to be re-triggerred. However,
the current code ignores the return value of xgbe_set_mode(), leading to
false information as the link is declared without checking the status
register.
Fix this by propagating the mode switch status information to
xgbe_phy_status().
Fixes: e57f7a3fea ("amd-xgbe: Prepare for working with more than one type of phy")
Co-developed-by: Sudheesh Mavila <sudheesh.mavila@amd.com>
Signed-off-by: Sudheesh Mavila <sudheesh.mavila@amd.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Acked-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
Signed-off-by: Raju Rangoju <Raju.Rangoju@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Russell King says:
====================
net: dsa: mv88e6xxx: prepare for phylink_pcs conversion
These two patches provide some preparation for converting the mv88e6xxx
DSA driver to use phylink_pcs rather than bolting the serdes bits into
the MAC calls.
In order to correctly drive mv88e6xxx hardware when the PCS code is
split, we need to force the link down while changing the configuration
of a port. This is provided for via the mac_prepare() and mac_finish()
methods, but DSA does not forward these on to DSA drivers.
Patch 1 adds support to the DSA core to forward these two methods to
DSA drivers, and patch 2 moves the code from mv88e6xxx_mac_config()
into the respective methods.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Move the link forcing out of mac_config() and into the mac_prepare()
and mac_finish() methods. This results in no change to the order in
which these operations are performed, but does mean when we convert
mv88e6xxx to phylink_pcs support, we will continue to preserve this
ordering.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add DSA support for the phylink mac_prepare() and mac_finish() calls.
These were introduced as part of the PCS support to allow MACs to
perform preparatory steps prior to configuration, and finalisation
steps after the MAC and PCS has been configured.
Introducing phylink_pcs support to the mv88e6xxx DSA driver needs some
code moved out of its mac_config() stage into the mac_prepare() and
mac_finish() stages, and this commit facilitates such code in DSA
drivers.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to support different power levels of 6 GHz AP and client, new WMI
event for regulatory (WMI_REG_CHAN_LIST_CC_EXT_EVENTID) has been added in
firmware to provide new parameters required for 6 GHz regulatory rules.
Firmware advertises its capability of handling new event in WMI service ready
event. Based on that, host needs to set host_service_flags in WMI init command
to indicate that host supports processing of this WMI event. Based on
advertised host capability, firmware sends event WMI_REG_CHAN_LIST_CC_EXT_EVENTID.
This new event contains 2G/5G/6G reg rules with additional power value fields
for 6GHz and regd is built accordingly.
Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.0-02903-QCAHKSWPL_SILICONZ-1
Signed-off-by: P Praneesh <quic_ppranees@quicinc.com>
Signed-off-by: Ramya Gnanasekar <quic_rgnanase@quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20230502142018.20301-1-quic_rgnanase@quicinc.com
Most protos' poll() methods insert a memory barrier between
writes to sk_err and sk_error_report(). This dates back to
commit a4d258036e ("tcp: Fix race in tcp_poll").
I guess we should do the same thing in TLS, tcp_poll() does
not hold the socket lock.
Fixes: 3c4d755915 ("tls: kernel TLS support")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To keep things simple we used to include the uAPI header
in the kernel in the #include <linux/$family.h> format.
This works well enough, most of the genl families should
have headers in include/net/ so linux/$family.h ends up
referring to the uAPI header, anyway. And if it doesn't
no big deal, we'll just include more info than we need.
Unless that is there is a naming conflict. Someone recently
created include/linux/psp.h which will be a problem when
supporting the PSP protocol. (I'm talking about
work-in-progress patches, but it's just a proof that assuming
lack of name conflicts was overly optimistic.)
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use <> instead of "" for including headers from include/.
Fixes: 8a9bf29546 ("drm/i915/gsc: add initial support for GSC proxy")
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Alan Previn <alan.previn.teres.alexis@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Luca Coelho <luciano.coelho@intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230525094942.941123-1-jani.nikula@intel.com
The newly added support for ECV CNTPOFF open codes the recently added
helper ARM64_CPUID_FIELDS(), make use of the helper. No functional
change.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/20230523-arm64-ecv-helper-v1-1-506dfb5fb199@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
There was a report that the hardware breakpoints and watch points weren't
reporting the debug architecture version as expected, they were reporting
a version of 0 which is not defined in the architecture. This happens
when running in a KVM guest if the host has a debug architecture version
not supported by KVM, it in turn confuses GDB which rejects any debug
architecture version it does not know about.
Add a test that covers that situation and while we're at it reports the
debug architecture version and number of slots available to aid with
figuring out problems that may arise.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230414-arm64-test-hw-breakpoint-v2-1-90a19e3b1059@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
When fewer VIs are allocated than what is allowed we can readjust
the channels by calling efx_mcdi_alloc_vis() again.
Signed-off-by: Pieter Jansen van Vuuren <pieter.jansen-van-vuuren@amd.com>
Reviewed-by: Martin Habets <habetsm.xilinx@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Edward Cree <ecree.xilinx@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The architecture has added more information about faults to ISS2 within
ESR. Add decode of this to our data abort fault decode to aid diagnostics.
Features that are not currently enabled are included here for completeness.
Since the architecture specifies the values of bits within ISS2 in terms
of ISS2 rather than in terms of the register as a whole we do so for our
definitions as well, this makes it easier to review bitfield definitions.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230417-arm64-iss2-dabt-decode-v3-2-c1fa503e503a@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
We express the mask for ESR_ELx.ISS in a non-standard manner, not using
the standard helpers. In preparation for adding decode for ISS2 convert to
use GENMASK(). No functional change.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230417-arm64-iss2-dabt-decode-v3-1-c1fa503e503a@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Clang warns:
drivers/gpu/drm/i915/display/intel_display.c:6012:3: error: unannotated fall-through between switch labels [-Werror,-Wimplicit-fallthrough]
case I915_FORMAT_MOD_X_TILED:
^
drivers/gpu/drm/i915/display/intel_display.c:6012:3: note: insert 'break;' to avoid fall-through
case I915_FORMAT_MOD_X_TILED:
^
break;
1 error generated.
Clang is a little more pedantic than GCC, which does not warn when
falling through to a case that is just break or return. Clang's version
is more in line with the kernel's own stance in deprecated.rst, which
states that all switch/case blocks must end in either break,
fallthrough, continue, goto, or return. Add the missing break to silence
the warning.
Fixes: 937859485a ("drm/i915: Support Async Flip on Linear buffers")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/202305241902.UvHtMoxa-lkp@intel.com/
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Closes: https://lore.kernel.org/CA+G9fYv68V3ewK0Qj-syQj7qX-hQr0H1MFL=QFNuDoE_J2Zu-g@mail.gmail.com/
Reported-by: Tom Rix <trix@redhat.com>
Closes: https://lore.kernel.org/all/20230523125116.1669057-1-trix@redhat.com/
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230524-intel_async_flip_check_hw-implicit-fallthrough-v1-1-83de89e376a1@kernel.org
In dw_pcie_host_init() regardless of whether the link has been
started or not, the code waits for the link to come up. Even in
cases where start_link() is not defined the code ends up spinning
in a loop for 1 second. Since in some systems dw_pcie_host_init()
gets called during probe, this one second loop for each pcie
interface instance ends up extending the boot time.
Wait for the link up in only if the start_link() is defined.
Link: https://lore.kernel.org/r/20230412093425.3659088-1-ajayagarwal@google.com
Tested-by: Will McVicker <willmcvicker@google.com>
Signed-off-by: Sajid Dalvi <sdalvi@google.com>
Signed-off-by: Ajay Agarwal <ajayagarwal@google.com>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
The previous setting was related to the overall dimension and not to the
active display area.
In the "PHYSICAL SPECIFICATIONS" section, the datasheet shows the
following parameters:
----------------------------------------------------------
| Item | Specifications | unit |
----------------------------------------------------------
| Display area | 98.7 (W) x 57.5 (H) | mm |
----------------------------------------------------------
| Overall dimension | 105.5(W) x 67.2(H) x 4.96(D) | mm |
----------------------------------------------------------
Fixes: 966fea78ad ("drm/panel: simple: Add support for Ampire AM-480272H3TMQW-T01H")
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
[narmstrong: fixed Fixes commit id length]
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230516085039.3797303-1-dario.binacchi@amarulasolutions.com
Busy polling is currently not allowed on PREEMPT_RT, because it disables
preemption while invoking the NAPI callback. It is not possible to acquire
sleeping locks with disabled preemption. For details see commit
20ab39d13e ("net/core: disable NET_RX_BUSY_POLL on PREEMPT_RT").
However, strict cyclic and/or low latency network applications may prefer busy
polling e.g., using AF_XDP instead of interrupt driven communication.
The preempt_disable() is used in order to prevent the poll_owner and NAPI owner
to be preempted while owning the resource to ensure progress. Netpoll performs
busy polling in order to acquire the lock. NAPI is locked by setting the
NAPIF_STATE_SCHED flag. There is no busy polling if the flag is set and the
"owner" is preempted. Worst case is that the task owning NAPI gets preempted and
NAPI processing stalls. This is can be prevented by properly prioritising the
tasks within the system.
Allow RX_BUSY_POLL on PREEMPT_RT if NETPOLL is disabled. Don't disable
preemption on PREEMPT_RT within the busy poll loop.
Tested on x86 hardware with v6.1-RT and v6.3-RT on Intel i225 (igc) with
AF_XDP/ZC sockets configured to run in busy polling mode.
Suggested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
In the event a device is connected to the samsung-dsim
controller that doesn't support the burst-clock, the
driver is able to get the requested pixel clock from the
attached device or bridge. In these instances, the
samsung,burst-clock-frequency isn't needed, so remove
it from the required list.
The pll-clock frequency can be set by the device tree entry
for samsung,pll-clock-frequency, but in some cases, the
pll-clock may have the same clock rate as sclk_mipi clock.
If they are equal, this flag is not needed since the driver
will use the sclk_mipi rate as a fallback.
Signed-off-by: Adam Ford <aford173@gmail.com>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230526030559.326566-8-aford173@gmail.com
The high-speed clock is hard-coded to the burst-clock
frequency specified in the device tree. However, when
using devices like certain bridge chips without burst mode
and varying resolutions and refresh rates, it may be
necessary to set the high-speed clock dynamically based
on the desired pixel clock for the connected device.
This also removes the need to set a clock speed from
the device tree for non-burst mode operation, since the
pixel clock rate is the rate requested from the attached
device like a bridge chip. This should have no impact
for people using burst-mode and setting the burst clock
rate is still required for those users. If the burst
clock is not present, change the error message to
dev_info indicating the clock use the pixel clock.
Signed-off-by: Adam Ford <aford173@gmail.com>
Tested-by: Chen-Yu Tsai <wenst@chromium.org>
Tested-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
Tested-by: Jagan Teki <jagan@amarulasolutions.com> # imx8mm-icore
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230526030559.326566-7-aford173@gmail.com
The DPHY timings are currently hard coded. Since the input
clock can be variable, the phy timings need to be variable
too. To facilitate this, we need to cache the hs_clock
based on what is generated from the PLL.
The phy_mipi_dphy_get_default_config_for_hsclk function
configures the DPHY timings in pico-seconds, and a small macro
converts those timings into clock cycles based on the hs_clk.
Signed-off-by: Adam Ford <aford173@gmail.com>
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Tested-by: Chen-Yu Tsai <wenst@chromium.org>
Tested-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Tested-by: Michael Walle <michael@walle.cc>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
Tested-by: Jagan Teki <jagan@amarulasolutions.com> # imx8mm-icore
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230526030559.326566-6-aford173@gmail.com
In order to support variable DPHY timings, it's necessary
to enable GENERIC_PHY_MIPI_DPHY so phy_mipi_dphy_get_default_config
can be used to determine the nominal values for a given resolution
and refresh rate.
Signed-off-by: Adam Ford <aford173@gmail.com>
Tested-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Tested-by: Chen-Yu Tsai <wenst@chromium.org>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230526030559.326566-5-aford173@gmail.com
Make the pll-clock-frequency optional. If it's present, use it
to maintain backwards compatibility with existing hardware. If it
is absent, read clock rate of "sclk_mipi" to determine the rate.
Since it can be optional, change the message from an error to
dev_info.
Signed-off-by: Adam Ford <aford173@gmail.com>
Tested-by: Chen-Yu Tsai <wenst@chromium.org>
Tested-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
Tested-by: Jagan Teki <jagan@amarulasolutions.com> # imx8mm-icore
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230526030559.326566-4-aford173@gmail.com
According to Table 13-45 of the i.MX8M Mini Reference Manual, the min
and max values for M and the frequency range for the VCO_out
calculator were incorrect. This information was contradicted in other
parts of the mini, nano and plus manuals. After reaching out to my
NXP Rep, when confronting him about discrepencies in the Nano manual,
he responded with:
"Yes it is definitely wrong, the one that is part
of the NOTE in MIPI_DPHY_M_PLLPMS register table against PMS_P,
PMS_M and PMS_S is not correct. I will report this to Doc team,
the one customer should be take into account is the Table 13-40
DPHY PLL Parameters and the Note above."
These updated values also match what is used in the NXP downstream
kernel.
To fix this, make new variables to hold the min and max values of m
and the minimum value of VCO_out, and update the PMS calculator to
use these new variables instead of using hard-coded values to keep
the backwards compatibility with other parts using this driver.
Fixes: 4d562c70c4 ("drm: bridge: samsung-dsim: Add i.MX8M Mini/Nano support")
Signed-off-by: Adam Ford <aford173@gmail.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Tested-by: Chen-Yu Tsai <wenst@chromium.org>
Tested-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
Tested-by: Jagan Teki <jagan@amarulasolutions.com> # imx8mm-icore
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230526030559.326566-3-aford173@gmail.com
Scale the blanking packet sizes to match the ratio between HS clock
and DPI interface clock. The controller seems to do internal scaling
to the number of active lanes, so we don't take those into account.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Adam Ford <aford173@gmail.com>
Tested-by: Chen-Yu Tsai <wenst@chromium.org>
Tested-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
Tested-by: Jagan Teki <jagan@amarulasolutions.com> # imx8mm-icore
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230526030559.326566-2-aford173@gmail.com
drm-misc-fixes for v6.4-rc4:
- A few non-trivial fixes to qaic.
- Fix drmm_mutex_init always using same lock class.
- Fix pl111 fb depth.
- Fix uninitialised gamma lut in mgag200.
- Add Aya Neo Air Plus quirk.
- Trivial null check removal in scheduler.
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/d19f748c-2c5b-8140-5b05-a8282dfef73e@linux.intel.com
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Merge tag 'mlx5-fixes-2023-05-24' of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux
Saeed Mahameed says:
====================
mlx5 fixes 2023-05-24
This series includes bug fixes for the mlx5 driver.
* tag 'mlx5-fixes-2023-05-24' of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux:
Documentation: net/mlx5: Wrap notes in admonition blocks
Documentation: net/mlx5: Add blank line separator before numbered lists
Documentation: net/mlx5: Use bullet and definition lists for vnic counters description
Documentation: net/mlx5: Wrap vnic reporter devlink commands in code blocks
net/mlx5: Fix check for allocation failure in comp_irqs_request_pci()
net/mlx5: DR, Add missing mutex init/destroy in pattern manager
net/mlx5e: Move Ethernet driver debugfs to profile init callback
net/mlx5e: Don't attach netdev profile while handling internal error
net/mlx5: Fix post parse infra to only parse every action once
net/mlx5e: Use query_special_contexts cmd only once per mdev
net/mlx5: fw_tracer, Fix event handling
net/mlx5: SF, Drain health before removing device
net/mlx5: Drain health before unregistering devlink
net/mlx5e: Do not update SBCM when prio2buffer command is invalid
net/mlx5e: Consider internal buffers size in port buffer calculations
net/mlx5e: Prevent encap offload when neigh update is running
net/mlx5e: Extract remaining tunnel encap code to dedicated file
====================
Link: https://lore.kernel.org/r/20230525034847.99268-1-saeed@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
syzkaller found a data race of pkt_sk(sk)->num.
The value is changed under lock_sock() and po->bind_lock, so we
need READ_ONCE() to access pkt_sk(sk)->num without these locks in
packet_bind_spkt(), packet_bind(), and sk_diag_fill().
Note that WRITE_ONCE() is already added by commit c7d2ef5dd4
("net/packet: annotate accesses to po->bind").
BUG: KCSAN: data-race in packet_bind / packet_do_bind
write (marked) to 0xffff88802ffd1cee of 2 bytes by task 7322 on cpu 0:
packet_do_bind+0x446/0x640 net/packet/af_packet.c:3236
packet_bind+0x99/0xe0 net/packet/af_packet.c:3321
__sys_bind+0x19b/0x1e0 net/socket.c:1803
__do_sys_bind net/socket.c:1814 [inline]
__se_sys_bind net/socket.c:1812 [inline]
__x64_sys_bind+0x40/0x50 net/socket.c:1812
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x72/0xdc
read to 0xffff88802ffd1cee of 2 bytes by task 7318 on cpu 1:
packet_bind+0xbf/0xe0 net/packet/af_packet.c:3322
__sys_bind+0x19b/0x1e0 net/socket.c:1803
__do_sys_bind net/socket.c:1814 [inline]
__se_sys_bind net/socket.c:1812 [inline]
__x64_sys_bind+0x40/0x50 net/socket.c:1812
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x72/0xdc
value changed: 0x0300 -> 0x0000
Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7318 Comm: syz-executor.4 Not tainted 6.3.0-13380-g7fddb5b5300c #4
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
Fixes: 96ec632714 ("packet: Diag core and basic socket info dumping")
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: syzkaller <syzkaller@googlegroups.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20230524232934.50950-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Python 3.9.0 or newer supports combining dicts() with |,
but older versions of Python are still used in the wild
(e.g. on CentOS 8, which goes EoL May 31, 2024).
With Python 3.6.8 we get:
TypeError: unsupported operand type(s) for |: 'dict' and 'dict'
Use older syntax. Tested with non-legacy families only.
Fixes: f036d936ca ("tools: ynl: Add fixed-header support to ynl")
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Tested-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/r/20230524170712.2036128-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Simon Kapadia reported the following issue:
<quote>
The Online Amateur Radio Community (OARC) has recently been experimenting
with building a nationwide packet network in the UK.
As part of our experimentation, we have been testing out packet on 300bps HF,
and playing with net/rom. For HF packet at this baud rate you really need
to make sure that your MTU is relatively low; AX.25 suggests a PACLEN of 60,
and a net/rom PACLEN of 40 to go with that.
However the Linux net/rom support didn't work with a low PACLEN;
the mkiss module would truncate packets if you set the PACLEN below about 200 or so, e.g.:
Apr 19 14:00:51 radio kernel: [12985.747310] mkiss: ax1: truncating oversized transmit packet!
This didn't make any sense to me (if the packets are smaller why would they
be truncated?) so I started investigating.
I looked at the packets using ethereal, and found that many were just huge
compared to what I would expect.
A simple net/rom connection request packet had the request and then a bunch
of what appeared to be random data following it:
</quote>
Simon provided a patch that I slightly revised:
Not only we must not use skb_tailroom(), we also do
not want to count NR_NETWORK_LEN twice.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Co-Developed-by: Simon Kapadia <szymon@kapadia.pl>
Signed-off-by: Simon Kapadia <szymon@kapadia.pl>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Tested-by: Simon Kapadia <szymon@kapadia.pl>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Link: https://lore.kernel.org/r/20230524141456.1045467-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We encountered a kernel call trace issue which was related to
ndo_xdp_xmit callback on our i.MX8MP platform. The reproduce
steps show as follows.
1. The FEC port (eth0) connects to a PC port, and the PC uses
pktgen_sample03_burst_single_flow.sh to generate packets and
send these packets to the FEC port. Notice that the script must
be executed before step 2.
2. Run the "./xdp_redirect eth0 eth1" command on i.MX8MP, the
eth1 interface is the dwmac. Then there will be a call trace
issue soon. Please see the log for more details.
The root cause is that the NETDEV_XDP_ACT_NDO_XMIT feature is
enabled by default, so when the step 2 command is exexcuted
and packets have already been sent to eth0, the stmmac_xdp_xmit()
starts running before the stmmac_xdp_set_prog() finishes. To
resolve this issue, we disable the NETDEV_XDP_ACT_NDO_XMIT
feature by default and turn on/off this feature when the bpf
program is installed/uninstalled which just like the other
ethernet drivers.
Call Trace log:
[ 306.311271] ------------[ cut here ]------------
[ 306.315910] WARNING: CPU: 0 PID: 15 at lib/timerqueue.c:55 timerqueue_del+0x68/0x70
[ 306.323590] Modules linked in:
[ 306.326654] CPU: 0 PID: 15 Comm: ksoftirqd/0 Not tainted 6.4.0-rc1+ #37
[ 306.333277] Hardware name: NXP i.MX8MPlus EVK board (DT)
[ 306.338591] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 306.345561] pc : timerqueue_del+0x68/0x70
[ 306.349577] lr : __remove_hrtimer+0x5c/0xa0
[ 306.353777] sp : ffff80000b7c3920
[ 306.357094] x29: ffff80000b7c3920 x28: 0000000000000000 x27: 0000000000000001
[ 306.364244] x26: ffff80000a763a40 x25: ffff0000d0285a00 x24: 0000000000000001
[ 306.371390] x23: 0000000000000001 x22: ffff000179389a40 x21: 0000000000000000
[ 306.378537] x20: ffff000179389aa0 x19: ffff0000d2951308 x18: 0000000000001000
[ 306.385686] x17: f1d3000000000000 x16: 00000000c39c1000 x15: 55e99bbe00001a00
[ 306.392835] x14: 09000900120aa8c0 x13: e49af1d300000000 x12: 000000000000c39c
[ 306.399987] x11: 100055e99bbe0000 x10: ffff8000090b1048 x9 : ffff8000081603fc
[ 306.407133] x8 : 000000000000003c x7 : 000000000000003c x6 : 0000000000000001
[ 306.414284] x5 : ffff0000d2950980 x4 : 0000000000000000 x3 : 0000000000000000
[ 306.421432] x2 : 0000000000000001 x1 : ffff0000d2951308 x0 : ffff0000d2951308
[ 306.428585] Call trace:
[ 306.431035] timerqueue_del+0x68/0x70
[ 306.434706] __remove_hrtimer+0x5c/0xa0
[ 306.438549] hrtimer_start_range_ns+0x2bc/0x370
[ 306.443089] stmmac_xdp_xmit+0x174/0x1b0
[ 306.447021] bq_xmit_all+0x194/0x4b0
[ 306.450612] __dev_flush+0x4c/0x98
[ 306.454024] xdp_do_flush+0x18/0x38
[ 306.457522] fec_enet_rx_napi+0x6c8/0xc68
[ 306.461539] __napi_poll+0x40/0x220
[ 306.465038] net_rx_action+0xf8/0x240
[ 306.468707] __do_softirq+0x128/0x3a8
[ 306.472378] run_ksoftirqd+0x40/0x58
[ 306.475961] smpboot_thread_fn+0x1c4/0x288
[ 306.480068] kthread+0x124/0x138
[ 306.483305] ret_from_fork+0x10/0x20
[ 306.486889] ---[ end trace 0000000000000000 ]---
Fixes: 66c0e13ad2 ("drivers: net: turn on XDP features")
Signed-off-by: Wei Fang <wei.fang@nxp.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Link: https://lore.kernel.org/r/20230524125714.357337-1-wei.fang@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Do skb_put() after a new skb has been successfully allocated otherwise
the reused skb leads to skb_panics or incorrect packet sizes.
Fixes: f92e1869d7 ("Add Mellanox BlueField Gigabit Ethernet driver")
Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Link: https://lore.kernel.org/r/20230524194908.147145-1-tbogendoerfer@suse.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'ib-leds-netdev-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/leds
Lee Jones says:
====================
Immutable branch between LEDs and netdev due for the v6.5 merge window
Andrew Lunn says:
Christian Marangi and I will be continuing the work of offloading LED
blinking to Ethernet MAC and PHY LED controllers. The next set of
patches is again cross subsystem, LEDs and netdev. It also requires
some patches you have in for-leds-next:
a286befc24e8 leds: trigger: netdev: Use mutex instead of spinlocks
509412749002 leds: trigger: netdev: Convert device attr to macro
0fd93ac85826 leds: trigger: netdev: Rename add namespace to netdev trigger enum modes
eb31ca4531a0 leds: trigger: netdev: Drop NETDEV_LED_MODE_LINKUP from mode
3fc498cf54b4 leds: trigger: netdev: Recheck NETDEV_LED_MODE_LINKUP on dev rename
I'm assuming the new series will get nerged via netdev, with your
Acked-by. Could you create a stable branch with these patches which
can be pulled into netdev?
* tag 'ib-leds-netdev-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/leds:
leds: trigger: netdev: Use mutex instead of spinlocks
leds: trigger: netdev: Convert device attr to macro
leds: trigger: netdev: Rename add namespace to netdev trigger enum modes
leds: trigger: netdev: Drop NETDEV_LED_MODE_LINKUP from mode
leds: trigger: netdev: Recheck NETDEV_LED_MODE_LINKUP on dev rename
====================
Link: https://lore.kernel.org/r/20230525111521.GA411262@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
If plen is null when passed in, we only checked for null
in one of the two places where it could be used. Although
plen is always valid (not null) for current callers of the
SMB2_change_notify function, this change makes it more consistent.
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Closes: https://lore.kernel.org/all/202305251831.3V1gbbFs-lkp@intel.com/
Signed-off-by: Steve French <stfrench@microsoft.com>
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Merge tag '6.4-rc3-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull smb directory moves and client fixes from Steve French:
"Four smb3 client fixes (three of which marked for stable) and three
patches to move of fs/cifs and fs/ksmbd to a new common "fs/smb"
parent directory
- Move the client and server source directories to a common parent
directory:
fs/cifs -> fs/smb/client
fs/ksmbd -> fs/smb/server
fs/smbfs_common -> fs/smb/common
- important readahead fix
- important fix for SMB1 regression
- fix for missing mount option ("mapchars") in mount API conversion
- minor debugging improvement"
* tag '6.4-rc3-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
smb3: move Documentation/filesystems/cifs to Documentation/filesystems/smb
cifs: correct references in Documentation to old fs/cifs path
smb: move client and server files to common directory fs/smb
cifs: mapchars mount option ignored
smb3: display debug information better for encryption
cifs: fix smb1 mount regression
cifs: Fix cifs_limit_bvec_subset() to correctly check the maxmimum size
- Fix flush_dcache_page() for usage from irq context
- Handle kprobes breakpoints only in kernel context
- Handle kgdb breakpoints only in kernel context
- Use num_present_cpus() in alternative patching code
- Enable LOCKDEP support
- Add lightweight spinlock checks
- Flush AGP gatt writes and adjust gatt mask in parisc_agp_mask_memory()
- Allow to reboot machine after system halt
- Improve cache flushing for PCXL in arch_sync_dma_for_cpu()
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Merge tag 'parisc-for-6.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc architecture fixes from Helge Deller:
"Quite a bunch of real bugfixes in here and most of them are tagged for
backporting: A fix for cache flushing from irq context, a kprobes &
kgdb breakpoint handling fix, and a fix in the alternative code
patching function to take care of CPU hotplugging.
parisc now provides LOCKDEP support and comes with a lightweight
spinlock check. Both features helped me to find the cache flush bug.
Additionally writing the AGP gatt has been fixed, the machine allows
the user to reboot after a system halt and arch_sync_dma_for_cpu() has
been optimized for PCXL PCUs.
Summary:
- Fix flush_dcache_page() for usage from irq context
- Handle kprobes breakpoints only in kernel context
- Handle kgdb breakpoints only in kernel context
- Use num_present_cpus() in alternative patching code
- Enable LOCKDEP support
- Add lightweight spinlock checks
- Flush AGP gatt writes and adjust gatt mask in parisc_agp_mask_memory()
- Allow to reboot machine after system halt
- Improve cache flushing for PCXL in arch_sync_dma_for_cpu()"
* tag 'parisc-for-6.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Fix flush_dcache_page() for usage from irq context
parisc: Handle kgdb breakpoints only in kernel context
parisc: Handle kprobes breakpoints only in kernel context
parisc: Allow to reboot machine after system halt
parisc: Enable LOCKDEP support
parisc: Add lightweight spinlock checks
parisc: Use num_present_cpus() in alternative patching code
parisc: Flush gatt writes and adjust gatt mask in parisc_agp_mask_memory()
parisc: Improve cache flushing for PCXL in arch_sync_dma_for_cpu()
It turns out that udev under certain circumstances will concurrently try
to load the same modules over-and-over excessively. This isn't a kernel
bug, but it ends up affecting the kernel, to the point that under
certain circumstances we can fail to boot, because the kernel uses a lot
of memory to read all the module data all at once.
Note that it isn't a memory leak, it's just basically a thundering herd
problem happening at bootup with a lot of CPUs, with the worst cases
then being pretty bad.
Admittedly the worst situations are somewhat contrived: lots and lots of
CPUs, not a lot of memory, and KASAN enabled to make it all slower and
as such (unintentionally) exacerbate the problem.
Luis explains: [1]
"My best assessment of the situation is that each CPU in udev ends up
triggering a load of duplicate set of modules, not just one, but *a
lot*. Not sure what heuristics udev uses to load a set of modules per
CPU."
Petr Pavlu chimes in: [2]
"My understanding is that udev workers are forked. An initial kmod
context is created by the main udevd process but no sharing happens
after the fork. It means that the mentioned memory pool logic doesn't
really kick in.
Multiple parallel load requests come from multiple udev workers, for
instance, each handling an udev event for one CPU device and making
the exactly same requests as all others are doing at the same time.
The optimization idea would be to recognize these duplicate requests
at the udevd/kmod level and converge them"
Note that module loading has tried to mitigate this issue before, see
for example commit 064f4536d1 ("module: avoid allocation if module is
already present and ready"), which has a few ASCII graphs on memory use
due to this same issue.
However, while that noticed that the module was already loaded, and
exited with an error early before spending any more time on setting up
the module, it didn't handle the case of multiple concurrent module
loads all being active - but not complete - at the same time.
Yes, one of them will eventually win the race and finalize its copy, and
the others will then notice that the module already exists and error
out, but while this all happens, we have tons of unnecessary concurrent
work being done.
Again, the real fix is for udev to not do that (maybe it should use
threads instead of fork, and have actual shared data structures and not
cause duplicate work). That real fix is apparently not trivial.
But it turns out that the kernel already has a pretty good model for
dealing with concurrent access to the same file: the i_writecount of the
inode.
In fact, the module loading already indirectly uses 'i_writecount' ,
because 'kernel_file_read()' will in fact do
ret = deny_write_access(file);
if (ret)
return ret;
...
allow_write_access(file);
around the read of the file data. We do not allow concurrent writes to
the file, and return -ETXTBUSY if the file was open for writing at the
same time as the module data is loaded from it.
And the solution to the reader concurrency problem is to simply extend
this "no concurrent writers" logic to simply be "exclusive access".
Note that "exclusive" in this context isn't really some absolute thing:
it's only exclusion from writers and from other "special readers" that
do this writer denial. So we simply introduce a variation of that
"deny_write_access()" logic that not only denies write access, but also
requires that this is the _only_ such access that denies write access.
Which means that you can't start loading a module that is already being
loaded as a module by somebody else, or you will get the same -ETXTBSY
error that you would get if there were writers around.
[ It also means that you can't try to load a currently executing
executable as a module, for the same reason: executables do that same
"deny_write_access()" thing, and that's obviously where the whole
ETXTBSY logic traditionally came from.
This is not a problem for kernel modules, since the set of normal
executable files and kernel module files is entirely disjoint. ]
This new function is called "exclusive_deny_write_access()", and the
implementation is trivial, in that it's just an atomic decrement of
i_writecount if it was 0 before.
To use that new exclusivity check, all we then do is wrap the module
loading with that exclusive_deny_write_access()() / allow_write_access()
pair. The actual patch is a bit bigger than that, because we want to
surround not just the "load file data" part, but the whole module setup,
to get maximum exclusion.
So this ends up splitting up "finit_module()" into a few helper
functions to make it all very clear and legible.
In Luis' test-case (bringing up 255 vcpu's in a virtual machine [3]),
the "wasted vmalloc" space (ie module data read into a vmalloc'ed area
in order to be loaded as a module, but then discarded because somebody
else loaded the same module instead) dropped from 1.8GiB to 474kB. Yes,
that's gigabytes to kilobytes.
It doesn't drop completely to zero, because even with this change, you
can still end up having completely serial pointless module loads, where
one udev process has loaded a module fully (and thus the kernel has
released that exclusive lock on the module file), and then another udev
process tries to load the same module again.
So while we cannot fully get rid of the fundamental bug in user space,
we _can_ get rid of the excessive concurrent thundering herd effect.
A couple of final side notes on this all:
- This tweak only affects the "finit_module()" system call, which gives
the kernel a file descriptor with the module data.
You can also just feed the module data as raw data from user space
with "init_module()" (note the lack of 'f' at the beginning), and
obviously for that case we do _not_ have any "exclusive read" logic.
So if you absolutely want to do things wrong in user space, and try
to load the same module multiple times, and error out only later when
the kernel ends up saying "you can't load the same module name
twice", you can still do that.
And in fact, some distros will do exactly that, because they will
uncompress the kernel module data in user space before feeding it to
the kernel (mainly because they haven't started using the new kernel
side decompression yet).
So this is not some absolute "you can't do concurrent loads of the
same module". It's literally just a very simple heuristic that will
catch it early in case you try to load the exact same module file at
the same time, and in that case avoid a potentially nasty situation.
- There is another user of "deny_write_access()": the verity code that
enables fs-verity on a file (the FS_IOC_ENABLE_VERITY ioctl).
If you use fs-verity and you care about verifying the kernel modules
(which does make sense), you should do it *before* loading said
kernel module. That may sound obvious, but now the implementation
basically requires it. Because if you try to do it concurrently, the
kernel may refuse to load the module file that is being set up by the
fs-verity code.
- This all will obviously mean that if you insist on loading the same
module in parallel, only one module load will succeed, and the others
will return with an error.
That was true before too, but what is different is that the -ETXTBSY
error can be returned *before* the success case of another process
fully loading and instantiating the module.
Again, that might sound obvious, and it is indeed the whole point of
the whole change: we are much quicker to notice the whole "you're
already in the process of loading this module".
So it's very much intentional, but it does mean that if you just
spray the kernel with "finit_module()", and expect that the module is
immediately loaded afterwards without checking the return value, you
are doing something horribly horribly wrong.
I'd like to say that that would never happen, but the whole _reason_
for this commit is that udev is currently doing something horribly
horribly wrong, so ...
Link: https://lore.kernel.org/all/ZEGopJ8VAYnE7LQ2@bombadil.infradead.org/ [1]
Link: https://lore.kernel.org/all/23bd0ce6-ef78-1cd8-1f21-0e706a00424a@suse.com/ [2]
Link: https://lore.kernel.org/lkml/ZG%2Fa+nrt4%2FAAUi5z@bombadil.infradead.org/ [3]
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Cc: Petr Pavlu <petr.pavlu@suse.com>
Tested-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The sockopt test invokes test__start_subtest and then unconditionally
asserts the success. That means that even if deny-listed, any test will
still run and potentially fail.
Evaluate the return value of test__start_subtest() to achieve the
desired behavior, as other tests do.
Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230525232248.640465-1-deso@posteo.net
