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Linux kernel
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Pull clk fix from Stephen Boyd:
"One build fix for 32-bit arches using the Qualcomm PLL driver. It's
cheaper to use a comparison here instead of a division so we just do
that to fix the build"
* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
clk: qcom: clk-alpha-pll: Simplify the zonda_pll_adjust_l_val()
Pull block fix from Jens Axboe:
"Just a single fix for a deadlock issue that can happen if someone
attempts to change the root disk IO scheduler with a module that
requires loading from disk.
Changing the scheduler freezes the queue while that operation is
happening, hence causing a deadlock"
* tag 'block-6.11-20240912' of git://git.kernel.dk/linux:
block: Prevent deadlocks when switching elevators
In zonda_pll_adjust_l_val() replace the divide operator with comparison
operator to fix below build error and smatch warning.
drivers/clk/qcom/clk-alpha-pll.o: In function `clk_zonda_pll_set_rate':
clk-alpha-pll.c:(.text+0x45dc): undefined reference to `__aeabi_uldivmod'
smatch warnings:
drivers/clk/qcom/clk-alpha-pll.c:2129 zonda_pll_adjust_l_val() warn: replace
divide condition '(remainder * 2) / prate' with '(remainder * 2) >= prate'
Fixes: f4973130d255 ("clk: qcom: clk-alpha-pll: Update set_rate for Zonda PLL")
Reported-by: Jon Hunter <jonathanh@nvidia.com>
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/r/202408110724.8pqbpDiD-lkp@intel.com/
Signed-off-by: Satya Priya Kakitapalli <quic_skakitap@quicinc.com>
Link: https://lore.kernel.org/r/20240906113905.641336-1-quic_skakitap@quicinc.com
Reviewed-by: Vladimir Zapolskiy <vladimir.zapolskiy@linaro.org>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Pull hwmon fix from Guenter Roeck:
- Fix clearing status register bits for chips supporting older
PMBus versions
* tag 'hwmon-for-v6.11-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
hwmon: (pmbus) Conditionally clear individual status bits for pmbus rev >= 1.2
Commit af2814149883 ("block: freeze the queue in queue_attr_store")
changed queue_attr_store() to always freeze a sysfs attribute queue
before calling the attribute store() method, to ensure that no IOs are
in-flight when an attribute value is being updated.
However, this change created a potential deadlock situation for the
scheduler queue attribute as changing the queue elevator with
elv_iosched_store() can result in a call to request_module() if the user
requested module is not already registered. If the file of the requested
module is stored on the block device of the frozen queue, a deadlock
will happen as the read operations triggered by request_module() will
wait for the queue freeze to end.
Solve this issue by introducing the load_module method in struct
queue_sysfs_entry, and to calling this method function in
queue_attr_store() before freezing the attribute queue.
The macro definition QUEUE_RW_LOAD_MODULE_ENTRY() is added to define a
queue sysfs attribute that needs loading a module.
The definition of the scheduler atrribute is changed to using
QUEUE_RW_LOAD_MODULE_ENTRY(), with the function
elv_iosched_load_module() defined as the load_module method.
elv_iosched_store() can then be simplified to remove the call to
request_module().
Reported-by: Richard W.M. Jones <rjones@redhat.com>
Reported-by: Jiri Jaburek <jjaburek@redhat.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219166
Fixes: af2814149883 ("block: freeze the queue in queue_attr_store")
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Link: https://lore.kernel.org/r/20240908000704.414538-1-dlemoal@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
A recent change started parking the RCG at an always on parent during
registration, something which specifically breaks handover from an early
serial console.
Quoting Stephen Boyd who fixed this issue for SM8550 [1]:
The QUPs aren't shared in a way that requires parking the RCG at
an always on parent in case some other entity turns on the clk.
The hardware is capable of setting a new frequency itself with
the DFS mode, so parking is unnecessary. Furthermore, there
aren't any GDSCs for these devices, so there isn't a possibility
of the GDSC turning on the clks for housekeeping purposes.
This wasn't a problem to mark these clks shared until we started
parking shared RCGs at clk registration time in commit
01a0a6cc8cfd ("clk: qcom: Park shared RCGs upon registration").
Parking at init is actually harmful to the UART when earlycon is
used. If the device is pumping out data while the frequency
changes you'll see garbage on the serial console until the
driver can probe and actually set a proper frequency.
Fixes: 01a0a6cc8cfd ("clk: qcom: Park shared RCGs upon registration")
Fixes: d65d005f9a6c ("clk: qcom: add sc8280xp GCC driver")
Link: https://lore.kernel.org/all/20240819233628.2074654-2-swboyd@chromium.org/ [1]
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/r/20240902070830.8535-1-johan+linaro@kernel.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Pull workqueue fix from Tejun Heo:
"A fix for a NULL worker->pool deref bug which can be triggered when a
worker is created and then destroyed immediately"
* tag 'wq-for-6.11-rc7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: Clear worker->pool in the worker thread context
The current implementation of pmbus_show_boolean assumes that all devices
support write-back operation of status register to clear pending warnings
or faults. Since clearing individual bits in the status registers was only
introduced in PMBus specification 1.2, this operation may not be supported
by some older devices. This can result in an error while reading boolean
attributes such as temp1_max_alarm.
Fetch PMBus revision supported by the device and modify pmbus_show_boolean
so that it only tries to clear individual status bits if the device is
compliant with PMBus specs >= 1.2. Otherwise clear all fault indicators
on the current page after a fault status was reported.
Fixes: 35f165f08950a ("hwmon: (pmbus) Clear pmbus fault/warning bits after read")
Signed-off-by: Patryk Biel <pbiel7@gmail.com>
Message-ID: <20240909-pmbus-status-reg-clearing-v1-1-f1c0d68c6408@gmail.com>
[groeck:
Rewrote description
Moved revision detection code ahead of clear faults command
Assigned revision if return value from PMBUS_REVISION command is 0
Improved return value check from calling _pmbus_write_byte_data()]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Pull NVMe fixes from Keith:
"nvme fixes for Linux 6.11
- Sparse fix on static symbol (Jinjie)
- Misleading warning message fix (Keith)
- TCP command allocation handling fix (Maurizio)
- PCI tagset allocation handling fix (Keith)
- Low-power quirk for Samsung (Georg)
- Queue limits fix for zone devices (Christoph)
- Target protocol behavior fix (Maurizio)"
* tag 'nvme-6.11-2024-09-05' of git://git.infradead.org/nvme:
nvmet: Identify-Active Namespace ID List command should reject invalid nsid
nvme: set BLK_FEAT_ZONED for ZNS multipath disks
nvme-pci: Add sleep quirk for Samsung 990 Evo
nvme-pci: allocate tagset on reset if necessary
nvmet-tcp: fix kernel crash if commands allocation fails
nvme: use better description for async reset reason
nvmet: Make nvmet_debugfs static
Add notifier function for PLL0 clock. In the function, the cpu_root clock
should be operated by saving its current parent and setting a new safe
parent (osc clock) before setting the PLL0 clock rate. After setting PLL0
rate, it should be switched back to the original parent clock.
Fixes: e2c510d6d630 ("riscv: dts: starfive: Add cpu scaling for JH7110 SoC")
Cc: stable@vger.kernel.org
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Xingyu Wu <xingyu.wu@starfivetech.com>
Link: https://lore.kernel.org/r/20240826080430.179788-2-xingyu.wu@starfivetech.com
Reviewed-by: Hal Feng <hal.feng@starfivetech.com>
Tested-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Pull RISC-V fixes from Palmer Dabbelt:
- Two fixes for smp_processor_id() calls in preemptible sections: one
if the perf driver, and one in the fence.i prctl.
* tag 'riscv-for-linus-6.11-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: Disable preemption while handling PR_RISCV_CTX_SW_FENCEI_OFF
drivers: perf: Fix smp_processor_id() use in preemptible code
Marc Hartmayer reported:
[ 23.133876] Unable to handle kernel pointer dereference in virtual kernel address space
[ 23.133950] Failing address: 0000000000000000 TEID: 0000000000000483
[ 23.133954] Fault in home space mode while using kernel ASCE.
[ 23.133957] AS:000000001b8f0007 R3:0000000056cf4007 S:0000000056cf3800 P:000000000000003d
[ 23.134207] Oops: 0004 ilc:2 [#1] SMP
(snip)
[ 23.134516] Call Trace:
[ 23.134520] [<0000024e326caf28>] worker_thread+0x48/0x430
[ 23.134525] ([<0000024e326caf18>] worker_thread+0x38/0x430)
[ 23.134528] [<0000024e326d3a3e>] kthread+0x11e/0x130
[ 23.134533] [<0000024e3264b0dc>] __ret_from_fork+0x3c/0x60
[ 23.134536] [<0000024e333fb37a>] ret_from_fork+0xa/0x38
[ 23.134552] Last Breaking-Event-Address:
[ 23.134553] [<0000024e333f4c04>] mutex_unlock+0x24/0x30
[ 23.134562] Kernel panic - not syncing: Fatal exception: panic_on_oops
With debuging and analysis, worker_thread() accesses to the nullified
worker->pool when the newly created worker is destroyed before being
waken-up, in which case worker_thread() can see the result detach_worker()
reseting worker->pool to NULL at the begining.
Move the code "worker->pool = NULL;" out from detach_worker() to fix the
problem.
worker->pool had been designed to be constant for regular workers and
changeable for rescuer. To share attaching/detaching code for regular
and rescuer workers and to avoid worker->pool being accessed inadvertently
when the worker has been detached, worker->pool is reset to NULL when
detached no matter the worker is rescuer or not.
To maintain worker->pool being reset after detached, move the code
"worker->pool = NULL;" in the worker thread context after detached.
It is either be in the regular worker thread context after PF_WQ_WORKER
is cleared or in rescuer worker thread context with wq_pool_attach_mutex
held. So it is safe to do so.
Cc: Marc Hartmayer <mhartmay@linux.ibm.com>
Link: https://lore.kernel.org/lkml/87wmjj971b.fsf@linux.ibm.com/
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Fixes: f4b7b53c94af ("workqueue: Detach workers directly in idle_cull_fn()")
Cc: stable@vger.kernel.org # v6.11+
Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
bio_integrity_add_page restricts the size of the integrity metadata to
queue_max_hw_sectors(q). This restriction is not needed because oversized
bios are split automatically. This restriction causes problems with
dm-integrity 'inline' mode - if we send a large bio to dm-integrity and
the bio's metadata are larger than queue_max_hw_sectors(q),
bio_integrity_add_page fails and the bio is ended with BLK_STS_RESOURCE
error.
An example that triggers it:
dd: error writing '/dev/mapper/in2': Cannot allocate memory
1+0 records in
0+0 records out
0 bytes copied, 0.00169291 s, 0.0 kB/s
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Fixes: fb0987682c62 ("dm-integrity: introduce the Inline mode")
Fixes: 0ece1d649b6d ("bio-integrity: create multi-page bvecs in bio_integrity_add_page()")
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Anuj Gupta <anuj20.g@samsung.com>
Link: https://lore.kernel.org/r/e41b3b8e-16c2-70cb-97cb-881234bb200d@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
nsid values of 0xFFFFFFFE and 0XFFFFFFFF should be rejected with
a status code of "Invalid Namespace or Format".
See NVMe Base Specification, Active Namespace ID list (CNS 02h).
Fixes: a07b4970f464 ("nvmet: add a generic NVMe target")
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Keith Busch <kbusch@kernel.org>
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