The AW2013 driver uses devm_regmap_init_i2c, so REGMAP_I2C needs to
be selected.
Otherwise build process may fail with:
ld: drivers/leds/leds-aw2013.o: in function `aw2013_probe':
leds-aw2013.c:345: undefined reference to `__devm_regmap_init_i2c'
Signed-off-by: Dang Huynh <danct12@riseup.net>
Acked-by: Nikita Travkin <nikita@trvn.ru>
Fixes: 59ea3c9faf ("leds: add aw2013 driver")
Link: https://lore.kernel.org/r/20231103114203.1108922-1-danct12@riseup.net
Signed-off-by: Lee Jones <lee@kernel.org>
Some Allwinner sunxi SoCs, starting with the A100, contain an LED
controller designed to drive RGB LED pixels. Add a driver for it using
the multicolor LED framework, and with LEDs defined in the device tree.
Acked-by: Guo Ren <guoren@kernel.org>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Samuel Holland <samuel@sholland.org>
Link: https://lore.kernel.org/r/20231029212738.7871-3-samuel@sholland.org
Signed-off-by: Lee Jones <lee@kernel.org>
The Allwinner A100, R329, and D1 SoCs contain an LED controller designed
to drive a series of RGB LED pixels. It supports PIO and DMA transfers,
and has configurable timing and pixel format. All three implementations
appear to be identical, so use the oldest as the fallback compatible.
Acked-by: Guo Ren <guoren@kernel.org>
Acked-by: Maxime Ripard <mripard@kernel.org>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Tested-by: Trevor Woerner <twoerner@gmail.com>
Signed-off-by: Samuel Holland <samuel@sholland.org>
Link: https://lore.kernel.org/r/20231029212738.7871-2-samuel@sholland.org
Signed-off-by: Lee Jones <lee@kernel.org>
A valid JSON pointer should begin with a '/'. The json-schema package is
lax on this allowing either form, but that's changing in new versions.
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20231122205418.2482076-1-robh@kernel.org
Signed-off-by: Lee Jones <lee@kernel.org>
The register-bit-led binding now also supports 'reg' in addition to
'offset' for the register address. Add support to the driver to get the
address from 'reg'.
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20231025190619.881090-2-robh@kernel.org
Signed-off-by: Lee Jones <lee@kernel.org>
CPU features can be determined in makedumpfile, using
'cur_cpu_spec.cpu_features'.
This provides more data to makedumpfile about the crashed system, and
can help in filtering the vmcore accordingly.
Signed-off-by: Aditya Gupta <adityag@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230920105706.853626-2-adityag@linux.ibm.com
kasprintf() returns a pointer to dynamically allocated memory
which can be NULL upon failure.
Fixes: 885dcd709b ("powerpc/perf: Add nest IMC PMU support")
Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231126093719.1440305-1-chentao@kylinos.cn
kasprintf() returns a pointer to dynamically allocated memory
which can be NULL upon failure.
Fixes: b9ef7b4b86 ("powerpc: Convert to using %pOFn instead of device_node.name")
Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231126095739.1501990-1-chentao@kylinos.cn
kasprintf() returns a pointer to dynamically allocated memory
which can be NULL upon failure.
Fixes: 2717a33d60 ("powerpc/opal-irqchip: Use interrupt names if present")
Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231127030755.1546750-1-chentao@kylinos.cn
kasprintf() returns a pointer to dynamically allocated memory
which can be NULL upon failure.
Add a null pointer check, and release 'ent' to avoid memory leaks.
Fixes: bfd2f0d49a ("powerpc/powernv: Get rid of old scom_controller abstraction")
Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231208085937.107210-1-chentao@kylinos.cn
kasprintf() returns a pointer to dynamically allocated memory
which can be NULL upon failure. Ensure the allocation was successful
by checking the pointer validity.
Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231204023223.2447523-1-chentao@kylinos.cn
The USB PHY nodes should not be described under 'simple-bus'.
Move it out of simple-bus.
Signed-off-by: Fabio Estevam <festevam@denx.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Per simple-bus.yaml, 'aipi' is not a valid node name.
Change it to 'bus' to fix the following dt-schema warning:
imx1-apf9328.dtb: aipi@200000: $nodename:0: 'aipi@200000' does not match '^([a-z][a-z0-9\\-]+-bus|bus|localbus|soc|axi|ahb|apb)(@.+)?$'
from schema $id: http://devicetree.org/schemas/simple-bus.yaml#
Signed-off-by: Fabio Estevam <festevam@denx.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
The USB PHY nodes should not be described under 'simple-bus'.
Move it out of simple-bus.
Signed-off-by: Fabio Estevam <festevam@denx.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
The USB PHY should not be described under 'simple-bus'.
Move it out of simple-bus.
Signed-off-by: Fabio Estevam <festevam@denx.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Per simple-bus.yaml, 'emi' is not a valid node name.
Change it to 'bus' to fix the following dt-schema warning:
imx25-pdk.dtb: emi@80000000: $nodename:0: 'emi@80000000' does not match '^([a-z][a-z0-9\\-]+-bus|bus|localbus|soc|axi|ahb|apb)(@.+)?$'
from schema $id: http://devicetree.org/schemas/simple-bus.yaml#
Signed-off-by: Fabio Estevam <festevam@denx.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Per simple-bus.yaml, 'aipi' is not a valid node name.
Change it to 'bus' to fix the following dt-schema warning:
imx27-pdk.dtb: aipi@10020000: $nodename:0: 'aipi@10020000' does not match '^([a-z][a-z0-9\\-]+-bus|bus|localbus|soc|axi|ahb|apb)(@.+)?$'
from schema $id: http://devicetree.org/schemas/simple-bus.yaml#
Signed-off-by: Fabio Estevam <festevam@denx.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
The hypervisor returns migration failure if all VAS windows are not
closed. During pre-migration stage, vas_migration_handler() sets
migration_in_progress flag and closes all windows from the list.
The allocate VAS window routine checks the migration flag, setup
the window and then add it to the list. So there is possibility of
the migration handler missing the window that is still in the
process of setup.
t1: Allocate and open VAS t2: Migration event
window
lock vas_pseries_mutex
If migration_in_progress set
unlock vas_pseries_mutex
return
open window HCALL
unlock vas_pseries_mutex
Modify window HCALL lock vas_pseries_mutex
setup window migration_in_progress=true
Closes all windows from the list
// May miss windows that are
// not in the list
unlock vas_pseries_mutex
lock vas_pseries_mutex return
if nr_closed_windows == 0
// No DLPAR CPU or migration
add window to the list
// Window will be added to the
// list after the setup is completed
unlock vas_pseries_mutex
return
unlock vas_pseries_mutex
Close VAS window
// due to DLPAR CPU or migration
return -EBUSY
This patch resolves the issue with the following steps:
- Set the migration_in_progress flag without holding mutex.
- Introduce nr_open_wins_progress counter in VAS capabilities
struct
- This counter tracks the number of open windows are still in
progress
- The allocate setup window thread closes windows if the migration
is set and decrements nr_open_window_progress counter
- The migration handler waits for no in-progress open windows.
The code flow with the fix is as follows:
t1: Allocate and open VAS t2: Migration event
window
lock vas_pseries_mutex
If migration_in_progress set
unlock vas_pseries_mutex
return
open window HCALL
nr_open_wins_progress++
// Window opened, but not
// added to the list yet
unlock vas_pseries_mutex
Modify window HCALL migration_in_progress=true
setup window lock vas_pseries_mutex
Closes all windows from the list
While nr_open_wins_progress {
unlock vas_pseries_mutex
lock vas_pseries_mutex sleep
if nr_closed_windows == 0 // Wait if any open window in
or migration is not started // progress. The open window
// No DLPAR CPU or migration // thread closes the window without
add window to the list // adding to the list and return if
nr_open_wins_progress-- // the migration is in progress.
unlock vas_pseries_mutex
return
Close VAS window
nr_open_wins_progress--
unlock vas_pseries_mutex
return -EBUSY lock vas_pseries_mutex
}
unlock vas_pseries_mutex
return
Fixes: 37e6764895 ("powerpc/pseries/vas: Add VAS migration handler")
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231125235104.3405008-1-haren@linux.ibm.com
Yanteng Si says:
====================
stmmac: Some bug fixes
* Put Krzysztof's patch into my thread, pick Conor's Reviewed-by
tag and Jiaxun's Acked-by tag.(prev version is RFC patch)
* I fixed an Oops related to mdio, mainly to ensure that
mdio is initialized before use, because it will be used
in a series of patches I am working on.
see <https://lore.kernel.org/loongarch/cover.1699533745.git.siyanteng@loongson.cn/T/#t>
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Device binds to proper PCI ID (LOONGSON, 0x7a03), already listed in DTS,
so checking for some other compatible does not make sense. It cannot be
bound to unsupported platform.
Drop useless, incorrect (space in between) and undocumented compatible.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Acked-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Device binds to proper PCI ID (LOONGSON, 0x7a03), already listed in DTS,
so checking for some other compatible does not make sense. It cannot be
bound to unsupported platform.
Drop useless, incorrect (space in between) and undocumented compatible.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Acked-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Generic code will use mdio. If it is not initialized before use,
the kernel will Oops.
Fixes: 30bba69d7d ("stmmac: pci: Add dwmac support for Loongson")
Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Signed-off-by: Feiyang Chen <chenfeiyang@loongson.cn>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Originally was in the panel-simple, but belongs to panel-simple-dsi.
See arch/arm/boot/dts/nvidia/tegra114-roth.dts for more details.
Resolves the following warning:
```
arch/arm/boot/dts/tegra114-roth.dt.yaml: panel@0: 'reg' does not match any of the regexes: 'pinctrl-[0-9]+'
From schema: Documentation/devicetree/bindings/display/panel/panel-simple.yaml
```
Fixes: 310abcea76 ("dt-bindings: display: convert simple lg panels to DT Schema")
Signed-off-by: David Heidelberg <david@ixit.cz>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Jessica Zhang <quic_jesszhan@quicinc.com>
Link: https://lore.kernel.org/r/20231212200934.99262-1-david@ixit.cz
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20231212200934.99262-1-david@ixit.cz
Commit d49a062621 ("arch: Introduce CONFIG_FUNCTION_ALIGNMENT")
introduced a generic function-alignment infrastructure. Move to using
FUNCTION_ALIGNMENT_4B on powerpc, to use the same alignment as that of
the existing _GLOBAL macro.
Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/21892186ec44abe24df0daf64f577dac0e78783f.1702045299.git.naveen@kernel.org
In the `ath_set_channel()` function, we only reset surveys that are not
from the current channel. This leads to the accumulation of survey data for
the current channel indefinitely. This may not be the most optimal
approach, as we want the ACS to rely on the most recent survey.
So reset the survey data for the current channel at the start of each scan.
Signed-off-by: Hancheng Yang <hyang@freebox.fr>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20231205170623.3029689-1-hyang@freebox.fr
Complete all counters on XGMAC Core.
These can be useful for debugging.
Signed-off-by: Furong Xu <0x1207@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Consistently testing system parameter access is a bit difficult by
nature -- the set of parameters available depends on the model and
system configuration, and updating a parameter should be considered a
destructive operation reserved for the admin.
So we validate some of the error paths and retrieve the SPLPAR
characteristics string, but not much else.
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231212-papr-sys_rtas-vs-lockdown-v6-13-e9eafd0c8c6c@linux.ibm.com
Add selftests for /dev/papr-vpd, exercising the common expected use
cases:
* Retrieve all VPD by passing an empty location code.
* Retrieve the "system VPD" by passing a location code derived from DT
root node properties, as done by the vpdupdate command.
The tests also verify that certain intended properties of the driver
hold:
* Passing an unterminated location code to PAPR_VPD_CREATE_HANDLE gets
EINVAL.
* Passing a NULL location code pointer to PAPR_VPD_CREATE_HANDLE gets
EFAULT.
* Closing the device node without first issuing a
PAPR_VPD_CREATE_HANDLE command to it succeeds.
* Releasing a handle without first consuming any data from it
succeeds.
* Re-reading the contents of a handle returns the same data as the
first time.
Some minimal validation of the returned data is performed.
The tests are skipped on systems where the papr-vpd driver does not
initialize, making this useful only on PowerVM LPARs at this point.
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231212-papr-sys_rtas-vs-lockdown-v6-12-e9eafd0c8c6c@linux.ibm.com
Until now the papr_sysparm APIs have been kernel-internal. But user
space needs access to PAPR system parameters too. The only method
available to user space today to get or set system parameters is using
sys_rtas() and /dev/mem to pass RTAS-addressable buffers between user
space and firmware. This is incompatible with lockdown and should be
deprecated.
So provide an alternative ABI to user space in the form of a
/dev/papr-sysparm character device with just two ioctl commands (get
and set). The data payloads involved are small enough to fit in the
ioctl argument buffer, making the code relatively simple.
Exposing the system parameters through sysfs has been considered but
it would be too awkward:
* The kernel currently does not have to contain an exhaustive list of
defined system parameters. This is a convenient property to maintain
because we don't have to update the kernel whenever a new parameter
is added to PAPR. Exporting a named attribute in sysfs for each
parameter would negate this.
* Some system parameters are text-based and some are not.
* Retrieval of at least one system parameter requires input data,
which a simple read-oriented interface can't support.
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231212-papr-sys_rtas-vs-lockdown-v6-11-e9eafd0c8c6c@linux.ibm.com
The ability to get and set system parameters will be exposed to user
space, so let's get a little more strict about malformed
papr_sysparm_buf objects.
* Create accessors for the length field of struct papr_sysparm_buf.
The length is always stored in MSB order and this is better than
spreading the necessary conversions all over.
* Reject attempts to submit invalid buffers to RTAS.
* Warn if RTAS returns a buffer with an invalid length, clamping the
returned length to a safe value that won't overrun the buffer.
These are meant as precautionary measures to mitigate both firmware
and kernel bugs in this area, should they arise, but I am not aware of
any.
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231212-papr-sys_rtas-vs-lockdown-v6-10-e9eafd0c8c6c@linux.ibm.com
PowerVM LPARs may retrieve Vital Product Data (VPD) for system
components using the ibm,get-vpd RTAS function.
We can expose this to user space with a /dev/papr-vpd character
device, where the programming model is:
struct papr_location_code plc = { .str = "", }; /* obtain all VPD */
int devfd = open("/dev/papr-vpd", O_RDONLY);
int vpdfd = ioctl(devfd, PAPR_VPD_CREATE_HANDLE, &plc);
size_t size = lseek(vpdfd, 0, SEEK_END);
char *buf = malloc(size);
pread(devfd, buf, size, 0);
When a file descriptor is obtained from ioctl(PAPR_VPD_CREATE_HANDLE),
the file contains the result of a complete ibm,get-vpd sequence. The
file contents are immutable from the POV of user space. To get a new
view of the VPD, the client must create a new handle.
This design choice insulates user space from most of the complexities
that ibm,get-vpd brings:
* ibm,get-vpd must be called more than once to obtain complete
results.
* Only one ibm,get-vpd call sequence should be in progress at a time;
interleaved sequences will disrupt each other. Callers must have a
protocol for serializing their use of the function.
* A call sequence in progress may receive a "VPD changed, try again"
status, requiring the client to abandon the sequence and start
over.
The memory required for the VPD buffers seems acceptable, around 20KB
for all VPD on one of my systems. And the value of the
/rtas/ibm,vpd-size DT property (the estimated maximum size of VPD) is
consistently 300KB across various systems I've checked.
I've implemented support for this new ABI in the rtas_get_vpd()
function in librtas, which the vpdupdate command currently uses to
populate its VPD database. I've verified that an unmodified vpdupdate
binary generates an identical database when using a librtas.so that
prefers the new ABI.
Along with the papr-vpd.h header exposed to user space, this
introduces a common papr-miscdev.h uapi header to share a base ioctl
ID with similar drivers to come.
Tested-by: Michal Suchánek <msuchanek@suse.de>
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231212-papr-sys_rtas-vs-lockdown-v6-9-e9eafd0c8c6c@linux.ibm.com
If the function descriptor has a populated lock member, then callers
are required to hold it across calls. Now that the firmware activation
sequence is appropriately guarded, we can warn when the requirement
isn't satisfied.
__do_enter_rtas_trace() gets reorganized a bit as a result of
performing the function descriptor lookup unconditionally now.
Reviewed-by: "Aneesh Kumar K.V (IBM)" <aneesh.kumar@kernel.org>
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231212-papr-sys_rtas-vs-lockdown-v6-8-e9eafd0c8c6c@linux.ibm.com
Use rtas_ibm_activate_firmware_lock to prevent interleaving call
sequences of the ibm,activate-firmware RTAS function, which typically
requires multiple calls to complete the update. While the spec does
not specifically prohibit interleaved sequences, there's almost
certainly no advantage to allowing them.
Reviewed-by: "Aneesh Kumar K.V (IBM)" <aneesh.kumar@kernel.org>
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231212-papr-sys_rtas-vs-lockdown-v6-7-e9eafd0c8c6c@linux.ibm.com
On RTAS platforms there is a general restriction that the OS must not
enter RTAS on more than one CPU at a time. This low-level
serialization requirement is satisfied by holding a spin
lock (rtas_lock) across most RTAS function invocations.
However, some pseries RTAS functions require multiple successive calls
to complete a logical operation. Beginning a new call sequence for such a
function may disrupt any other sequences of that function already in
progress. Safe and reliable use of these functions effectively
requires higher-level serialization beyond what is already done at the
level of RTAS entry and exit.
Where a sequence-based RTAS function is invoked only through
sys_rtas(), with no in-kernel users, there is no issue as far as the
kernel is concerned. User space is responsible for appropriately
serializing its call sequences. (Whether user space code actually
takes measures to prevent sequence interleaving is another matter.)
Examples of such functions currently include ibm,platform-dump and
ibm,get-vpd.
But where a sequence-based RTAS function has both user space and
in-kernel uesrs, there is a hazard. Even if the in-kernel call sites
of such a function serialize their sequences correctly, a user of
sys_rtas() can invoke the same function at any time, potentially
disrupting a sequence in progress.
So in order to prevent disruption of kernel-based RTAS call sequences,
they must serialize not only with themselves but also with sys_rtas()
users, somehow. Preferably without adding more function-specific hacks
to sys_rtas(). This is a prerequisite for adding an in-kernel call
sequence of ibm,get-vpd, which is in a change to follow.
Note that it has never been feasible for the kernel to prevent
sys_rtas()-based sequences from being disrupted because control
returns to user space on every call. sys_rtas()-based users of these
functions have always been, and continue to be, responsible for
coordinating their call sequences with other users, even those which
may invoke the RTAS functions through less direct means than
sys_rtas(). This is an unavoidable consequence of exposing
sequence-based RTAS functions through sys_rtas().
* Add an optional mutex member to struct rtas_function.
* Statically define a mutex for each RTAS function with known call
sequence serialization requirements, and assign its address to the
.lock member of the corresponding function table entry, along with
justifying commentary.
* In sys_rtas(), if the table entry for the RTAS function being
called has a populated lock member, acquire it before taking
rtas_lock and entering RTAS.
* Kernel-based RTAS call sequences are expected to access the
appropriate mutex explicitly by name. For example, a user of the
ibm,activate-firmware RTAS function would do:
int token = rtas_function_token(RTAS_FN_IBM_ACTIVATE_FIRMWARE);
int fwrc;
mutex_lock(&rtas_ibm_activate_firmware_lock);
do {
fwrc = rtas_call(token, 0, 1, NULL);
} while (rtas_busy_delay(fwrc));
mutex_unlock(&rtas_ibm_activate_firmware_lock);
There should be no perceivable change introduced here except that
concurrent callers of the same RTAS function via sys_rtas() may block
on a mutex instead of spinning on rtas_lock.
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231212-papr-sys_rtas-vs-lockdown-v6-6-e9eafd0c8c6c@linux.ibm.com
The rtas system call handler sys_rtas() delegates certain input
validation steps to a helper function: block_rtas_call(). One of these
steps ensures that the user-supplied token value maps to a known RTAS
function. This is done by performing a "reverse" token-to-function
lookup via rtas_token_to_function_untrusted() to obtain an
rtas_function object.
In changes to come, sys_rtas() itself will need the function
descriptor for the token. To prepare:
* Move the lookup and validation up into sys_rtas() and pass the
resulting rtas_function pointer to block_rtas_call(), which is
otherwise unconcerned with the token value.
* Change block_rtas_call() to report the RTAS function name instead of
the token value on validation failures, since it can now rely on
having a valid function descriptor.
One behavior change is that sys_rtas() now silently errors out when
passed a bad token, before calling block_rtas_call(). So we will no
longer log "RTAS call blocked - exploit attempt?" on invalid
tokens. This is consistent with how sys_rtas() currently handles other
"metadata" (nargs and nret), while block_rtas_call() is primarily
concerned with validating the arguments to be passed to specific RTAS
functions.
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231212-papr-sys_rtas-vs-lockdown-v6-5-e9eafd0c8c6c@linux.ibm.com
Not all of the generic RTAS function statuses specified in PAPR have
symbolic constants and descriptions in rtas.h. Fix this, providing a
little more background, slightly updating the existing wording, and
improving the formatting.
Reviewed-by: "Aneesh Kumar K.V (IBM)" <aneesh.kumar@kernel.org>
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231212-papr-sys_rtas-vs-lockdown-v6-4-e9eafd0c8c6c@linux.ibm.com
Enabling any of the powerpc:rtas_* tracepoints at boot is likely to
result in an oops on RTAS platforms. For example, booting a QEMU
pseries model with 'trace_event=powerpc:rtas_input' in the command
line leads to:
BUG: Kernel NULL pointer dereference on read at 0x00000008
Oops: Kernel access of bad area, sig: 7 [#1]
NIP [c00000000004231c] do_enter_rtas+0x1bc/0x460
LR [c00000000004231c] do_enter_rtas+0x1bc/0x460
Call Trace:
do_enter_rtas+0x1bc/0x460 (unreliable)
rtas_call+0x22c/0x4a0
rtas_get_boot_time+0x80/0x14c
read_persistent_clock64+0x124/0x150
read_persistent_wall_and_boot_offset+0x28/0x58
timekeeping_init+0x70/0x348
start_kernel+0xa0c/0xc1c
start_here_common+0x1c/0x20
(This is preceded by a warning for the failed lookup in
rtas_token_to_function().)
This happens when __do_enter_rtas_trace() attempts a token to function
descriptor lookup before the xarray containing the mappings has been
set up.
Fall back to linear scan of the table if rtas_token_to_function_xarray
is empty.
Fixes: 24098f580e ("powerpc/rtas: add tracepoints around RTAS entry")
Reviewed-by: "Aneesh Kumar K.V (IBM)" <aneesh.kumar@kernel.org>
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231212-papr-sys_rtas-vs-lockdown-v6-3-e9eafd0c8c6c@linux.ibm.com
Add a convenience macro for iterating over every element of the
internal function table and convert the one site that can use it. An
additional user of the macro is anticipated in changes to follow.
Reviewed-by: "Aneesh Kumar K.V (IBM)" <aneesh.kumar@kernel.org>
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231212-papr-sys_rtas-vs-lockdown-v6-2-e9eafd0c8c6c@linux.ibm.com
rtas_token_to_function() WARNs when passed an invalid token; it's
meant to catch bugs in kernel-based users of RTAS functions. However,
user space controls the token value passed to rtas_token_to_function()
by block_rtas_call(), so user space with sufficient privilege to use
sys_rtas() can trigger the warnings at will:
unexpected failed lookup for token 2048
WARNING: CPU: 20 PID: 2247 at arch/powerpc/kernel/rtas.c:556
rtas_token_to_function+0xfc/0x110
...
NIP rtas_token_to_function+0xfc/0x110
LR rtas_token_to_function+0xf8/0x110
Call Trace:
rtas_token_to_function+0xf8/0x110 (unreliable)
sys_rtas+0x188/0x880
system_call_exception+0x268/0x530
system_call_common+0x160/0x2c4
It's desirable to continue warning on bogus tokens in
rtas_token_to_function(). Currently it is used to look up RTAS
function descriptors when tracing, where we know there has to have
been a successful descriptor lookup by different means already, and it
would be a serious inconsistency for the reverse lookup to fail.
So instead of weakening rtas_token_to_function()'s contract by
removing the warnings, introduce rtas_token_to_function_untrusted(),
which has no opinion on failed lookups. Convert block_rtas_call() and
rtas_token_to_function() to use it.
Fixes: 8252b88294 ("powerpc/rtas: improve function information lookups")
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231212-papr-sys_rtas-vs-lockdown-v6-1-e9eafd0c8c6c@linux.ibm.com
Based on the tcp man page, if TCP_NODELAY is set, it disables Nagle's algorithm
and packets are sent as soon as possible. However in the `tcp_push` function
where autocorking is evaluated the `nonagle` value set by TCP_NODELAY is not
considered which can trigger unexpected corking of packets and induce delays.
For example, if two packets are generated as part of a server's reply, if the
first one is not transmitted on the wire quickly enough, the second packet can
trigger the autocorking in `tcp_push` and be delayed instead of sent as soon as
possible. It will either wait for additional packets to be coalesced or an ACK
from the client before transmitting the corked packet. This can interact badly
if the receiver has tcp delayed acks enabled, introducing 40ms extra delay in
completion times. It is not always possible to control who has delayed acks
set, but it is possible to adjust when and how autocorking is triggered.
Patch prevents autocorking if the TCP_NODELAY flag is set on the socket.
Patch has been tested using an AWS c7g.2xlarge instance with Ubuntu 22.04 and
Apache Tomcat 9.0.83 running the basic servlet below:
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class HelloWorldServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=utf-8");
OutputStreamWriter osw = new OutputStreamWriter(response.getOutputStream(),"UTF-8");
String s = "a".repeat(3096);
osw.write(s,0,s.length());
osw.flush();
}
}
Load was applied using wrk2 (https://github.com/kinvolk/wrk2) from an AWS
c6i.8xlarge instance. With the current auto-corking behavior and TCP_NODELAY
set an additional 40ms latency from P99.99+ values are observed. With the
patch applied we see no occurrences of 40ms latencies. The patch has also been
tested with iperf and uperf benchmarks and no regression was observed.
# No patch with tcp_autocorking=1 and TCP_NODELAY set on all sockets
./wrk -t32 -c128 -d40s --latency -R10000 http://172.31.49.177:8080/hello/hello'
...
50.000% 0.91ms
75.000% 1.12ms
90.000% 1.46ms
99.000% 1.73ms
99.900% 1.96ms
99.990% 43.62ms <<< 40+ ms extra latency
99.999% 48.32ms
100.000% 49.34ms
# With patch
./wrk -t32 -c128 -d40s --latency -R10000 http://172.31.49.177:8080/hello/hello'
...
50.000% 0.89ms
75.000% 1.13ms
90.000% 1.44ms
99.000% 1.67ms
99.900% 1.78ms
99.990% 2.27ms <<< no 40+ ms extra latency
99.999% 3.71ms
100.000% 4.57ms
Fixes: f54b311142 ("tcp: auto corking")
Signed-off-by: Salvatore Dipietro <dipiets@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Christian Marangi says:
====================
net: phy: at803x: cleanup
The intention of this big series is to try to cleanup the big
at803x PHY driver.
It currently have 3 different family of PHY in it. at803x, qca83xx
and qca808x.
The current codebase required lots of cleanup and reworking to
make the split possible as currently there is a greater use of
adding special function matching the phy_id.
This has been reworked to make the function actually generic
and make the change only in more specific one. The result
is the addition of micro additional function but that is for good
as it massively simplify splitting the driver later.
Consider that this is all in preparation for the addition of
qca807x PHY driver that will also uso some of the functions of
at803x.
Subsequent series will come with the actual PHY split and other
required cleanup. This is only to start the process with minor
changes.
Changes v4:
- Improve at8031_probe function
Changes v3:
- Add Reviewed-by tag from Andrew
- Split patch 10 (at8031 rename) to rename and move
Changes v2:
- Drop split part due to series too big
- Split changes even more
- Fix problem pointed out by Russell (flawed reworked function logic)
- Add Reviewed-by tag from Andrew
- Minor rework to prevent further code duplication for cdt
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Drop specific PHY ID check for cable test functions for at803x. This is
done to make functions more generic. While at it better describe what
the functions does by using more symbolic function names.
PHYs that requires to set additional reg are moved to specific function
calling the more generic one.
cdt_start and cdt_wait_for_completion are changed to take an additional
arg to pass specific values specific to the PHY.
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move at8035 specific DT parse for clock out frequency to dedicated probe
to make at803x probe function more generic.
This is to tidy code and no behaviour change are intended.
Detection logic is changed, we check if the clk 25m mask is set and if
it's not zero, we assume the qca,clk-out-frequency property is set.
The property is checked in the generic at803x_parse_dt called by
at803x_probe.
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move at8031 functions in dedicated section with dedicated at8031
parse_dt and probe.
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rename at8031 related DT function name to a more specific name
referencing they are only related to at8031 and not to the generic
at803x PHY family.
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move specific at8031 config_intr bits to dedicated function to make
at803x_config_initr more generic.
This is needed in preparation for PHY driver split as qca8081 share the
same function to setup interrupts.
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>