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Linux kernel
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Pull i2c fixes from Wolfram Sang:
- subsystem: convert drivers to use recent callbacks of struct
i2c_algorithm A typical after-rc1 cleanup, which I couldn't send in
time for rc2
- tegra: fix YAML conversion of device tree bindings
- k1: re-add a check which got lost during upstreaming
* tag 'i2c-for-6.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: k1: check for transfer error
i2c: use inclusive callbacks in struct i2c_algorithm
dt-bindings: i2c: nvidia,tegra20-i2c: Specify the required properties
Pull x86 fixes from Borislav Petkov:
- Make sure the array tracking which kernel text positions need to be
alternatives-patched doesn't get mishandled by out-of-order
modifications, leading to it overflowing and causing page faults when
patching
- Avoid an infinite loop when early code does a ranged TLB invalidation
before the broadcast TLB invalidation count of how many pages it can
flush, has been read from CPUID
- Fix a CONFIG_MODULES typo
- Disable broadcast TLB invalidation when PTI is enabled to avoid an
overflow of the bitmap tracking dynamic ASIDs which need to be
flushed when the kernel switches between the user and kernel address
space
- Handle the case of a CPU going offline and thus reporting zeroes when
reading top-level events in the resctrl code
* tag 'x86_urgent_for_v6.16_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/alternatives: Fix int3 handling failure from broken text_poke array
x86/mm: Fix early boot use of INVPLGB
x86/its: Fix an ifdef typo in its_alloc()
x86/mm: Disable INVLPGB when PTI is enabled
x86,fs/resctrl: Remove inappropriate references to cacheinfo in the resctrl subsystem
If spacemit_i2c_xfer_msg() times out waiting for a message transfer to
complete, or if the hardware reports an error, it returns a negative
error code (-ETIMEDOUT, -EAGAIN, -ENXIO. or -EIO).
The sole caller of spacemit_i2c_xfer_msg() is spacemit_i2c_xfer(),
which is the i2c_algorithm->xfer callback function. It currently
does not save the value returned by spacemit_i2c_xfer_msg().
The result is that transfer errors go unreported, and a caller
has no indication anything is wrong.
When this code was out for review, the return value *was* checked
in early versions. But for some reason, that assignment got dropped
between versions 5 and 6 of the series, perhaps related to reworking
the code to merge spacemit_i2c_xfer_core() into spacemit_i2c_xfer().
Simply assigning the value returned to "ret" fixes the problem.
Fixes: 5ea558473fa31 ("i2c: spacemit: add support for SpacemiT K1 SoC")
Signed-off-by: Alex Elder <elder@riscstar.com>
Cc: <stable@vger.kernel.org> # v6.15+
Reviewed-by: Troy Mitchell <troymitchell988@gmail.com>
Link: https://lore.kernel.org/r/20250616125137.1555453-1-elder@riscstar.com
Signed-off-by: Andi Shyti <andi@smida.it>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Pull irq fixes from Borislav Petkov:
- Fix missing prototypes warnings
- Properly initialize work context when allocating it
- Remove a method tracking when managed interrupts are suspended during
hotplug, in favor of the code using a IRQ disable depth tracking now,
and have interrupts get properly enabled again on restore
- Make sure multiple CPUs getting hotplugged don't cause wrong tracking
of the managed IRQ disable depth
* tag 'irq_urgent_for_v6.16_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/ath79-misc: Fix missing prototypes warnings
genirq/irq_sim: Initialize work context pointers properly
genirq/cpuhotplug: Restore affinity even for suspended IRQ
genirq/cpuhotplug: Rebalance managed interrupts across multi-CPU hotplug
Since smp_text_poke_single() does not expect there is another
text_poke request is queued, it can make text_poke_array not
sorted or cause a buffer overflow on the text_poke_array.vec[].
This will cause an Oops in int3 because of bsearch failing;
CPU 0 CPU 1 CPU 2
----- ----- -----
smp_text_poke_batch_add()
smp_text_poke_single() <<-- Adds out of order
<int3>
[Fails o find address
in text_poke_array ]
OOPS!
Or unhandled page fault because of a buffer overflow;
CPU 0 CPU 1
----- -----
smp_text_poke_batch_add() <<+
... |
smp_text_poke_batch_add() <<-- Adds TEXT_POKE_ARRAY_MAX times.
smp_text_poke_single() {
__smp_text_poke_batch_add() <<-- Adds entry at
TEXT_POKE_ARRAY_MAX + 1
smp_text_poke_batch_finish()
[Unhandled page fault because
text_poke_array.nr_entries is
overwritten]
BUG!
}
Use smp_text_poke_batch_add() instead of __smp_text_poke_batch_add()
so that it correctly flush the queue if needed.
Closes: https://lore.kernel.org/all/CA+G9fYsLu0roY3DV=tKyqP7FEKbOEETRvTDhnpPxJGbA=Cg+4w@mail.gmail.com/
Fixes: c8976ade0c1b ("x86/alternatives: Simplify smp_text_poke_single() by using tp_vec and existing APIs")
Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Tested-by: Linux Kernel Functional Testing <lkft@linaro.org>
Link: https://lkml.kernel.org/r/\ 175020512308.3582717.13631440385506146631.stgit@mhiramat.tok.corp.google.com
i2c-host-fixes for v6.16-rc2
tegra: fix YAML conversion of device tree bindings
Pull perf fixes from Borislav Petkov:
- Avoid a crash on a heterogeneous machine where not all cores support
the same hw events features
- Avoid a deadlock when throttling events
- Document the perf event states more
- Make sure a number of perf paths switching off or rescheduling events
call perf_cgroup_event_disable()
- Make sure perf does task sampling before its userspace mapping is
torn down, and not after
* tag 'perf_urgent_for_v6.16_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel: Fix crash in icl_update_topdown_event()
perf: Fix the throttle error of some clock events
perf: Add comment to enum perf_event_state
perf/core: Fix WARN in perf_cgroup_switch()
perf: Fix dangling cgroup pointer in cpuctx
perf: Fix cgroup state vs ERROR
perf: Fix sample vs do_exit()
ath79_misc_irq_init() was defined but unused since commit 51fa4f8912c0
("MIPS: ath79: drop legacy IRQ code"), so it's time to drop it.
The build also warns about a missing prototype of get_c0_perfcount_int().
Remove the stale leftover function and add the missing include.
Signed-off-by: Shiji Yang <yangshiji66@outlook.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/OSBPR01MB167032D2017645200787AAEBBC72A@OSBPR01MB1670.jpnprd01.prod.outlook.com
The INVLPGB instruction has limits on how many pages it can invalidate
at once. That limit is enumerated in CPUID, read by the kernel, and
stored in 'invpgb_count_max'. Ranged invalidation, like
invlpgb_kernel_range_flush() break up their invalidations so
that they do not exceed the limit.
However, early boot code currently attempts to do ranged
invalidation before populating 'invlpgb_count_max'. There is a
for loop which is basically:
for (...; addr < end; addr += invlpgb_count_max*PAGE_SIZE)
If invlpgb_kernel_range_flush is called before the kernel has read
the value of invlpgb_count_max from the hardware, the normally
bounded loop can become an infinite loop if invlpgb_count_max is
initialized to zero.
Fix that issue by initializing invlpgb_count_max to 1.
This way INVPLGB at early boot time will be a little bit slower
than normal (with initialized invplgb_count_max), and not an
instant hang at bootup time.
Fixes: b7aa05cbdc52 ("x86/mm: Add INVLPGB support code")
Signed-off-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/all/20250606171112.4013261-3-riel%40surriel.com
Convert the I2C subsystem to drop using the 'master_'-prefixed callbacks
in favor of the simplified ones. Fix alignment of '=' while here.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Specify the properties which are essential and which are not for the
Tegra I2C driver to function correctly. This was not added correctly when
the TXT binding was converted to yaml. All the existing DT nodes have
these properties already and hence this does not break the ABI.
dmas and dma-names which were specified as a must in the TXT binding
is now made optional since the driver can work in PIO mode if dmas are
missing.
Fixes: f10a9b722f80 ("dt-bindings: i2c: tegra: Convert to json-schema”)
Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
Cc: <stable@vger.kernel.org> # v5.17+
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Andi Shyti <andi@smida.it>
Link: https://lore.kernel.org/r/20250603153022.39434-1-akhilrajeev@nvidia.com
Pull locking fixes from Borislav Petkov:
- Make sure the switch to the global hash is requested always under a
lock so that two threads requesting that simultaneously cannot get to
inconsistent state
- Reject negative NUMA nodes earlier in the futex NUMA interface
handling code
- Selftests fixes
* tag 'locking_urgent_for_v6.16_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
futex: Verify under the lock if hash can be replaced
futex: Handle invalid node numbers supplied by user
selftests/futex: Set the home_node in futex_numa_mpol
selftests/futex: getopt() requires int as return value.
The perf_fuzzer found a hard-lockup crash on a RaptorLake machine:
Oops: general protection fault, maybe for address 0xffff89aeceab400: 0000
CPU: 23 UID: 0 PID: 0 Comm: swapper/23
Tainted: [W]=WARN
Hardware name: Dell Inc. Precision 9660/0VJ762
RIP: 0010:native_read_pmc+0x7/0x40
Code: cc e8 8d a9 01 00 48 89 03 5b cd cc cc cc cc 0f 1f ...
RSP: 000:fffb03100273de8 EFLAGS: 00010046
....
Call Trace:
<TASK>
icl_update_topdown_event+0x165/0x190
? ktime_get+0x38/0xd0
intel_pmu_read_event+0xf9/0x210
__perf_event_read+0xf9/0x210
CPUs 16-23 are E-core CPUs that don't support the perf metrics feature.
The icl_update_topdown_event() should not be invoked on these CPUs.
It's a regression of commit:
f9bdf1f95339 ("perf/x86/intel: Avoid disable PMU if !cpuc->enabled in sample read")
The bug introduced by that commit is that the is_topdown_event() function
is mistakenly used to replace the is_topdown_count() call to check if the
topdown functions for the perf metrics feature should be invoked.
Fix it.
Fixes: f9bdf1f95339 ("perf/x86/intel: Avoid disable PMU if !cpuc->enabled in sample read")
Closes: https://lore.kernel.org/lkml/352f0709-f026-cd45-e60c-60dfd97f73f3@maine.edu/
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Vince Weaver <vincent.weaver@maine.edu>
Cc: stable@vger.kernel.org # v6.15+
Link: https://lore.kernel.org/r/20250612143818.2889040-1-kan.liang@linux.intel.com
Initialize `ops` member's pointers properly by using kzalloc() instead of
kmalloc() when allocating the simulation work context. Otherwise the
pointers contain random content leading to invalid dereferencing.
Signed-off-by: Gyeyoung Baek <gye976@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250612124827.63259-1-gye976@gmail.com
Commit a82b26451de1 ("x86/its: explicitly manage permissions for ITS
pages") reworks its_alloc() and introduces a typo in an ifdef
conditional, referring to CONFIG_MODULE instead of CONFIG_MODULES.
Fix this typo in its_alloc().
Fixes: a82b26451de1 ("x86/its: explicitly manage permissions for ITS pages")
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@redhat.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/all/20250616100432.22941-1-lukas.bulwahn%40redhat.com
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