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Pull cxl fixes from Dan Williams:
"A build regression fix, a device compatibility fix, and an original
bug preventing creation of large (16 device) interleave sets:
- Fix unit test build regression fallout from global
"missing-prototypes" change
- Fix compatibility with devices that do not support interrupts
- Fix overflow when calculating the capacity of large interleave sets"
* tag 'cxl-fixes-6.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl:
cxl/region：Fix overflow issue in alloc_hpa()
cxl/pci: Skip irq features if MSI/MSI-X are not supported
tools/testing/nvdimm: Disable "missing prototypes / declarations" warnings
tools/testing/cxl: Disable "missing prototypes / declarations" warnings
Pull MIPS fixes from Thomas Bogendoerfer:
- fix boot issue on single core Lantiq Danube devices
- fix boot issue on Loongson64 platforms
- fix improper FPU setup
- fix missing prototypes issues
* tag 'mips-fixes_6.8_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
mips: Call lose_fpu(0) before initializing fcr31 in mips_set_personality_nan
MIPS: loongson64: set nid for reserved memblock region
Revert "MIPS: loongson64: set nid for reserved memblock region"
MIPS: lantiq: register smp_ops on non-smp platforms
MIPS: loongson64: set nid for reserved memblock region
MIPS: reserve exception vector space ONLY ONCE
MIPS: BCM63XX: Fix missing prototypes
MIPS: sgi-ip32: Fix missing prototypes
MIPS: sgi-ip30: Fix missing prototypes
MIPS: fw arc: Fix missing prototypes
MIPS: sgi-ip27: Fix missing prototypes
MIPS: Alchemy: Fix missing prototypes
MIPS: Cobalt: Fix missing prototypes
Creating a region with 16 memory devices caused a problem. The div_u64_rem
function, used for dividing an unsigned 64-bit number by a 32-bit one,
faced an issue when SZ_256M * p->interleave_ways. The result surpassed
the maximum limit of the 32-bit divisor (4G), leading to an overflow
and a remainder of 0.
note: At this point, p->interleave_ways is 16, meaning 16 * 256M = 4G
To fix this issue, I replaced the div_u64_rem function with div64_u64_rem
and adjusted the type of the remainder.
Signed-off-by: Quanquan Cao <caoqq@fujitsu.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Fixes: 23a22cd1c98b ("cxl/region: Allocate HPA capacity to regions")
Cc: <stable@vger.kernel.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull locking fix from Borislav Petkov:
- Prevent an inconsistent futex operation leading to stale state
exposure
* tag 'locking_urgent_for_v6.8_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
futex: Prevent the reuse of stale pi_state
If we still own the FPU after initializing fcr31, when we are preempted
the dirty value in the FPU will be read out and stored into fcr31,
clobbering our setting. This can cause an improper floating-point
environment after execve(). For example:
zsh% cat measure.c
#include <fenv.h>
int main() { return fetestexcept(FE_INEXACT); }
zsh% cc measure.c -o measure -lm
zsh% echo $((1.0/3)) # raising FE_INEXACT
0.33333333333333331
zsh% while ./measure; do ; done
(stopped in seconds)
Call lose_fpu(0) before setting fcr31 to prevent this.
Closes: https://lore.kernel.org/linux-mips/7a6aa1bbdbbe2e63ae96ff163fab0349f58f1b9e.camel@xry111.site/
Fixes: 9b26616c8d9d ("MIPS: Respect the ISA level in FCSR handling")
Cc: stable@vger.kernel.org
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
CXL 3.1 Section 3.1.1 states:
"A Function on a CXL device must not generate INTx messages if
that Function participates in CXL.cache protocol or CXL.mem
protocols."
The generic CXL memory driver only supports devices which use the
CXL.mem protocol. The current driver attempts to allocate MSI/MSI-X
vectors in anticipation of their need for mailbox interrupts or event
processing. However, the above requirement does not require a device to
support interrupts, only that they use MSI/MSI-X. For example, a device
may disable mailbox interrupts and either be configured for firmware
first or skip event processing and function.
Dave Larsen reported that the following Intel / Agilex card does not
support interrupts on function 0.
CXL: Intel Corporation Device 0ddb (rev 01) (prog-if 10 [CXL Memory Device (CXL 2.x)])
Rather than fail device probe if interrupts are not supported; flag that
irqs are not enabled and avoid features which require interrupts.
Emit messages appropriate for the situation to aid in debugging should
device behavior be unexpected due to a failure to allocate vectors.
Note that it is possible for a device to have host based event
processing through polling. However, the driver does not support
polling and it is not anticipated to be generally required. Leave that
functionality to a future patch if such a device comes along.
Reported-by: Dave Larsen <davelarsen58@gmail.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Fan Ni <fan.ni@samsung.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-and-tested-by: Davidlohr Bueso <dave@stgolabs.net>
Link: https://lore.kernel.org/r/20240117-dont-fail-irq-v2-1-f33f26b0e365@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull irq fix from Borislav Petkov:
- Initialize the resend node of each IRQ descriptor, not only the first
one
* tag 'irq_urgent_for_v6.8_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq: Initialize resend_node hlist for all interrupt descriptors
Jiri Slaby reported a futex state inconsistency resulting in -EINVAL during
a lock operation for a PI futex. It requires that the a lock process is
interrupted by a timeout or signal:
T1 Owns the futex in user space.
T2 Tries to acquire the futex in kernel (futex_lock_pi()). Allocates a
pi_state and attaches itself to it.
T2 Times out and removes its rt_waiter from the rt_mutex. Drops the
rtmutex lock and tries to acquire the hash bucket lock to remove
the futex_q. The lock is contended and T2 schedules out.
T1 Unlocks the futex (futex_unlock_pi()). Finds a futex_q but no
rt_waiter. Unlocks the futex (do_uncontended) and makes it available
to user space.
T3 Acquires the futex in user space.
T4 Tries to acquire the futex in kernel (futex_lock_pi()). Finds the
existing futex_q of T2 and tries to attach itself to the existing
pi_state. This (attach_to_pi_state()) fails with -EINVAL because uval
contains the TID of T3 but pi_state points to T1.
It's incorrect to unlock the futex and make it available for user space to
acquire as long as there is still an existing state attached to it in the
kernel.
T1 cannot hand over the futex to T2 because T2 already gave up and started
to clean up and is blocked on the hash bucket lock, so T2's futex_q with
the pi_state pointing to T1 is still queued.
T2 observes the futex_q, but ignores it as there is no waiter on the
corresponding rt_mutex and takes the uncontended path which allows the
subsequent caller of futex_lock_pi() (T4) to observe that stale state.
To prevent this the unlock path must dequeue all futex_q entries which
point to the same pi_state when there is no waiter on the rt mutex. This
requires obviously to make the dequeue conditional in the locking path to
prevent a double dequeue. With that it's guaranteed that user space cannot
observe an uncontended futex which has kernel state attached.
Fixes: fbeb558b0dd0d ("futex/pi: Fix recursive rt_mutex waiter state")
Reported-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20240118115451.0TkD_ZhB@linutronix.de
Closes: https://lore.kernel.org/all/4611bcf2-44d0-4c34-9b84-17406f881003@kernel.org
Commit 61167ad5fecd("mm: pass nid to reserve_bootmem_region()") reveals
that reserved memblock regions have no valid node id set, just set it
right since loongson64 firmware makes it clear in memory layout info.
This works around booting failure on 3A1000+ since commit 61167ad5fecd
("mm: pass nid to reserve_bootmem_region()") under
CONFIG_DEFERRED_STRUCT_PAGE_INIT.
Signed-off-by: Huang Pei <huangpei@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Prevent warnings of the form:
tools/testing/nvdimm/config_check.c:4:6: error: no previous prototype
for ‘check’ [-Werror=missing-prototypes]
...by locally disabling some warnings.
It turns out that:
Commit 0fcb70851fbf ("Makefile.extrawarn: turn on missing-prototypes globally")
...in addition to expanding in-tree coverage, also impacts out-of-tree
module builds like those in tools/testing/nvdimm/.
Filter out the warning options on unit test code that does not effect
mainline builds.
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Link: https://lore.kernel.org/r/170543984331.460832.1780246477583036191.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull timer fixes from Borislav Petkov:
- Preserve the number of idle calls and sleep entries across CPU
hotplug events in order to be able to compute correct averages
- Limit the duration of the clocksource watchdog checking interval as
too long intervals lead to wrongly marking the TSC as unstable
* tag 'timers_urgent_for_v6.8_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tick/sched: Preserve number of idle sleeps across CPU hotplug events
clocksource: Skip watchdog check for large watchdog intervals
For a CONFIG_SPARSE_IRQ=n kernel, early_irq_init() is supposed to
initialize all interrupt descriptors.
It does except for irq_desc::resend_node, which ia only initialized for the
first descriptor.
Use the indexed decriptor and not the base pointer to address that.
Fixes: bc06a9e08742 ("genirq: Use hlist for managing resend handlers")
Signed-off-by: Dawei Li <dawei.li@shingroup.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240122085716.2999875-5-dawei.li@shingroup.cn
Pull char/misc and other driver updates from Greg KH:
"Here is the big set of char/misc and other driver subsystem changes
for 6.8-rc1.
Other than lots of binder driver changes (as you can see by the merge
conflicts) included in here are:
- lots of iio driver updates and additions
- spmi driver updates
- eeprom driver updates
- firmware driver updates
- ocxl driver updates
- mhi driver updates
- w1 driver updates
- nvmem driver updates
- coresight driver updates
- platform driver remove callback api changes
- tags.sh script updates
- bus_type constant marking cleanups
- lots of other small driver updates
All of these have been in linux-next for a while with no reported
issues"
* tag 'char-misc-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (341 commits)
android: removed duplicate linux/errno
uio: Fix use-after-free in uio_open
drivers: soc: xilinx: add check for platform
firmware: xilinx: Export function to use in other module
scripts/tags.sh: remove find_sources
scripts/tags.sh: use -n to test archinclude
scripts/tags.sh: add local annotation
scripts/tags.sh: use more portable -path instead of -wholename
scripts/tags.sh: Update comment (addition of gtags)
firmware: zynqmp: Convert to platform remove callback returning void
firmware: turris-mox-rwtm: Convert to platform remove callback returning void
firmware: stratix10-svc: Convert to platform remove callback returning void
firmware: stratix10-rsu: Convert to platform remove callback returning void
firmware: raspberrypi: Convert to platform remove callback returning void
firmware: qemu_fw_cfg: Convert to platform remove callback returning void
firmware: mtk-adsp-ipc: Convert to platform remove callback returning void
firmware: imx-dsp: Convert to platform remove callback returning void
firmware: coreboot_table: Convert to platform remove callback returning void
firmware: arm_scpi: Convert to platform remove callback returning void
firmware: arm_scmi: Convert to platform remove callback returning void
...
This reverts commit ce7b1b97776ec0b068c4dd6b6dbb48ae09a23519.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Prevent warnings of the form:
tools/testing/cxl/test/mock.c:44:6: error: no previous prototype for
‘__wrap_is_acpi_device_node’ [-Werror=missing-prototypes]
tools/testing/cxl/test/mock.c:63:5: error: no previous prototype for
‘__wrap_acpi_table_parse_cedt’ [-Werror=missing-prototypes]
tools/testing/cxl/test/mock.c:81:13: error: no previous prototype for
‘__wrap_acpi_evaluate_integer’ [-Werror=missing-prototypes]
...by locally disabling some warnings.
It turns out that:
Commit 0fcb70851fbf ("Makefile.extrawarn: turn on missing-prototypes globally")
...in addition to expanding in-tree coverage, also impacts out-of-tree
module builds like those in tools/testing/cxl/.
Filter out the warning options on unit test code that does not effect
mainline builds.
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Link: https://lore.kernel.org/r/170543983780.460832.10920261849128601697.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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