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Linux kernel
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Pull misc x86 fixes from Ingo Molnar:
- Fix a possible CPU hotplug deadlock bug caused by the new TSC
synchronization code
- Fix a legacy PIC discovery bug that results in device troubles on
affected systems, such as non-working keybards, etc
- Add a new Intel CPU model number to <asm/intel-family.h>
* tag 'x86-urgent-2023-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/tsc: Defer marking TSC unstable to a worker
x86/i8259: Skip probing when ACPI/MADT advertises PCAT compatibility
x86/cpu: Add model number for Intel Arrow Lake mobile processor
Pull irq fix from Ingo Molnar:
"Restore unintentionally lost quirk settings in the GIC irqchip driver,
which broke certain devices"
* tag 'irq-urgent-2023-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/gic-v3-its: Don't override quirk settings with default values
Tetsuo reported the following lockdep splat when the TSC synchronization
fails during CPU hotplug:
tsc: Marking TSC unstable due to check_tsc_sync_source failed
WARNING: inconsistent lock state
inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
ffffffff8cfa1c78 (watchdog_lock){?.-.}-{2:2}, at: clocksource_watchdog+0x23/0x5a0
{IN-HARDIRQ-W} state was registered at:
_raw_spin_lock_irqsave+0x3f/0x60
clocksource_mark_unstable+0x1b/0x90
mark_tsc_unstable+0x41/0x50
check_tsc_sync_source+0x14f/0x180
sysvec_call_function_single+0x69/0x90
Possible unsafe locking scenario:
lock(watchdog_lock);
<Interrupt>
lock(watchdog_lock);
stack backtrace:
_raw_spin_lock+0x30/0x40
clocksource_watchdog+0x23/0x5a0
run_timer_softirq+0x2a/0x50
sysvec_apic_timer_interrupt+0x6e/0x90
The reason is the recent conversion of the TSC synchronization function
during CPU hotplug on the control CPU to a SMP function call. In case
that the synchronization with the upcoming CPU fails, the TSC has to be
marked unstable via clocksource_mark_unstable().
clocksource_mark_unstable() acquires 'watchdog_lock', but that lock is
taken with interrupts enabled in the watchdog timer callback to minimize
interrupt disabled time. That's obviously a possible deadlock scenario,
Before that change the synchronization function was invoked in thread
context so this could not happen.
As it is not crucical whether the unstable marking happens slightly
delayed, defer the call to a worker thread which avoids the lock context
problem.
Fixes: 9d349d47f0e3 ("x86/smpboot: Make TSC synchronization function call based")
Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/87zg064ceg.ffs@tglx
Pull perf event fix from Ingo Molnar:
"Fix a potential NULL dereference bug"
* tag 'perf-urgent-2023-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix potential NULL deref
When splitting the allocation of the ITS node from its configuration,
some of the default settings were kept in the latter instead of
being moved to the former.
This has the side effect of negating some of the quirk detections that
have happened in between, amongst which the dreaded Synquacer hack
(that also affect Dominic's TI platform).
Move the initialisation of these fields early, so that they can again be
overriden by the Synquacer quirk.
Fixes: 9585a495ac93 ("irqchip/gic-v3-its: Split allocation from initialisation of its_node")
Reported by: Dominic Rath <dominic.rath@ibv-augsburg.net>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Dominic Rath <dominic.rath@ibv-augsburg.net>
Link: https://lore.kernel.org/r/20231024084831.GA3788@JADEVM-DRA
Link: https://lore.kernel.org/r/20231024143431.2144579-1-maz@kernel.org
David and a few others reported that on certain newer systems some legacy
interrupts fail to work correctly.
Debugging revealed that the BIOS of these systems leaves the legacy PIC in
uninitialized state which makes the PIC detection fail and the kernel
switches to a dummy implementation.
Unfortunately this fallback causes quite some code to fail as it depends on
checks for the number of legacy PIC interrupts or the availability of the
real PIC.
In theory there is no reason to use the PIC on any modern system when
IO/APIC is available, but the dependencies on the related checks cannot be
resolved trivially and on short notice. This needs lots of analysis and
rework.
The PIC detection has been added to avoid quirky checks and force selection
of the dummy implementation all over the place, especially in VM guest
scenarios. So it's not an option to revert the relevant commit as that
would break a lot of other scenarios.
One solution would be to try to initialize the PIC on detection fail and
retry the detection, but that puts the burden on everything which does not
have a PIC.
Fortunately the ACPI/MADT table header has a flag field, which advertises
in bit 0 that the system is PCAT compatible, which means it has a legacy
8259 PIC.
Evaluate that bit and if set avoid the detection routine and keep the real
PIC installed, which then gets initialized (for nothing) and makes the rest
of the code with all the dependencies work again.
Fixes: e179f6914152 ("x86, irq, pic: Probe for legacy PIC and set legacy_pic appropriately")
Reported-by: David Lazar <dlazar@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: David Lazar <dlazar@gmail.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Cc: stable@vger.kernel.org
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218003
Link: https://lore.kernel.org/r/875y2u5s8g.ffs@tglx
Merge tag 'probes-fixes-v6.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull probes fixes from Masami Hiramatsu:
- tracing/kprobes: Fix kernel-doc warnings for the variable length
arguments
- tracing/kprobes: Fix to count the symbols in modules even if the
module name is not specified so that user can probe the symbols in
the modules without module name
* tag 'probes-fixes-v6.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing/kprobes: Fix symbol counting logic by looking at modules as well
tracing/kprobes: Fix the description of variable length arguments
Smatch is awesome.
Fixes: 32671e3799ca ("perf: Disallow mis-matched inherited group reads")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull irqchip fixes from Marc Zyngier:
- DT binding updates for Renesas r8a779f0 and rzg2l
- Let GICv3 honor the "dma-non-coherent" attribute for systems that
rely on SW guessing what the HW supports
- Fix the RISC-V INTC probing by marking all devices as initialised
at once
- Properly translate interrupt numbers from DT on stm32-exti
- Use irq_data_get_irq_chip_data() in the rzg2l driver instead of
blindly dereferencing the irq_data structure
- Add a MAINTAINERS entry for the various ARM GIC irqchip drivers
- Remove myself as the top-level irqchip/irqdomain maintainer
Link: https://lore.kernel.org/all/20231007121933.3840357-1-maz@kernel.org
For "reasons" Intel has code-named this CPU with a "_H" suffix.
[ dhansen: As usual, apply this and send it upstream quickly to
make it easier for anyone who is doing work that
consumes this. ]
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/all/20231025202513.12358-1-tony.luck%40intel.com
Pull dma-mapping fix from Christoph Hellwig:
- reduce the initialy dynamic swiotlb size to remove an annoying but
harmless warning from the page allocator (Petr Tesarik)
* tag 'dma-mapping-6.6-2023-10-28' of git://git.infradead.org/users/hch/dma-mapping:
swiotlb: do not try to allocate a TLB bigger than MAX_ORDER pages
Recent changes to count number of matching symbols when creating
a kprobe event failed to take into account kernel modules. As such, it
breaks kprobes on kernel module symbols, by assuming there is no match.
Fix this my calling module_kallsyms_on_each_symbol() in addition to
kallsyms_on_each_match_symbol() to perform a proper counting.
Link: https://lore.kernel.org/all/20231027233126.2073148-1-andrii@kernel.org/
Cc: Francis Laniel <flaniel@linux.microsoft.com>
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Fixes: b022f0c7e404 ("tracing/kprobes: Return EADDRNOTAVAIL when func matches several symbols")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Pull irqchip fixes from Marc Zygnier:
- Fix QC PDC v3.2 support by working around broken firmware tables
- Fix rzg2l-irqc missing #interrupt-cells description in the DT binding
- Fix rzg2l-irqc interrupt masking
Link: https://lore.kernel.org/lkml/20230924094105.2361754-1-maz@kernel.org
It is pretty obvious that I haven't done much on the IRQ side
for a while, and it is unlikely that I'll have more bandwidth
for it any time soon. People keep sending me patches that
I end-up reviewing in a cursory manner, which isn't great for
anyone.
So in everyone's interest, I'm removing myself from the list
of maintainers and leave the irqchip and irqdomain subsystems
in Thomas' capable hands.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231002141302.3409485-3-maz@kernel.org
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