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Pull clk fix from Stephen Boyd:
"One hotfix for a NULL pointer deref in the Renesas usb clk driver"
* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
clk: renesas: rcar-usb2-clock-sel: Fix kernel NULL pointer dereference
Pull scheduler fixes from Borislav Petkov:
- Have get_push_task() check whether current has migration disabled and
thus avoid useless invocations of the migration thread
- Rework initialization flow so that all rq->core's are initialized,
even of CPUs which have not been onlined yet, so that iterating over
them all works as expected
* tag 'sched_urgent_for_v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched: Fix get_push_task() vs migrate_disable()
sched: Fix Core-wide rq->lock for uninitialized CPUs
The probe was manually passing NULL instead of dev to devm_clk_hw_register.
This caused a Unable to handle kernel NULL pointer dereference error.
Fix this by passing 'dev'.
Signed-off-by: Adam Ford <aford173@gmail.com>
Fixes: a20a40a8bbc2 ("clk: renesas: rcar-usb2-clock-sel: Fix error handling in .probe()")
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Pull irq fix from Borislav Petkov:
- Have msix_mask_all() check a global control which says whether MSI-X
masking should be done and thus make it usable on Xen-PV too
* tag 'irq_urgent_for_v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
PCI/MSI: Skip masking MSI-X on Xen PV
push_rt_task() attempts to move the currently running task away if the
next runnable task has migration disabled and therefore is pinned on the
current CPU.
The current task is retrieved via get_push_task() which only checks for
nr_cpus_allowed == 1, but does not check whether the task has migration
disabled and therefore cannot be moved either. The consequence is a
pointless invocation of the migration thread which correctly observes
that the task cannot be moved.
Return NULL if the task has migration disabled and cannot be moved to
another CPU.
Fixes: a7c81556ec4d3 ("sched: Fix migrate_disable() vs rt/dl balancing")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210826133738.yiotqbtdaxzjsnfj@linutronix.de
As GDSCs are registered and found to be already enabled gdsc_init()
ensures that 1) the kernel state matches the hardware state, and 2)
votable GDSCs are properly enabled from this master as well.
But as the (optional) supply regulator is enabled deep into
gdsc_toggle_logic(), which is only executed for votable GDSCs, the
kernel's state of the regulator might not match the hardware. The
regulator might be automatically turned off if no other users are
present or the next call to gdsc_disable() would cause an unbalanced
regulator_disable().
Given that the votable case deals with an already enabled GDSC, most of
gdsc_enable() and gdsc_toggle_logic() can be skipped. Reduce it to just
clearing the SW_COLLAPSE_MASK and enabling hardware control to simply
call regulator_enable() in both cases.
The enablement of hardware control seems to be an independent property
from the GDSC being enabled, so this is moved outside that conditional
segment.
Lastly, as the propagation of ALWAYS_ON to GENPD_FLAG_ALWAYS_ON needs to
happen regardless of the initial state this is grouped together with the
other sc->pd updates at the end of the function.
Cc: stable@vger.kernel.org
Fixes: 37416e554961 ("clk: qcom: gdsc: Handle GDSC regulator supplies")
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20210721224056.3035016-1-bjorn.andersson@linaro.org
[sboyd@kernel.org: Rephrase commit text]
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Pull perf fixes from Borislav Petkov:
- Prevent the amd/power module from being removed while in use
- Mark AMD IBS as not supporting content exclusion
- Add a workaround for AMD erratum #1197 where IBS registers might not
be restored properly after exiting CC6 state
- Fix a potential truncation of a 32-bit variable due to shifting
- Read the correct bits describing the number of configurable address
ranges on Intel PT
* tag 'perf_urgent_for_v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/amd/power: Assign pmu.module
perf/x86/amd/ibs: Extend PERF_PMU_CAP_NO_EXCLUDE to IBS Op
perf/x86/amd/ibs: Work around erratum #1197
perf/x86/intel/uncore: Fix integer overflow on 23 bit left shift of a u32
perf/x86/intel/pt: Fix mask of num_address_ranges
When running as Xen PV guest, masking MSI-X is a responsibility of the
hypervisor. The guest has no write access to the relevant BAR at all - when
it tries to, it results in a crash like this:
BUG: unable to handle page fault for address: ffffc9004069100c
#PF: supervisor write access in kernel mode
#PF: error_code(0x0003) - permissions violation
RIP: e030:__pci_enable_msix_range.part.0+0x26b/0x5f0
e1000e_set_interrupt_capability+0xbf/0xd0 [e1000e]
e1000_probe+0x41f/0xdb0 [e1000e]
local_pci_probe+0x42/0x80
(...)
The recently introduced function msix_mask_all() does not check the global
variable pci_msi_ignore_mask which is set by XEN PV to bypass the masking
of MSI[-X] interrupts.
Add the check to make this function XEN PV compatible.
Fixes: 7d5ec3d36123 ("PCI/MSI: Mask all unused MSI-X entries")
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210826170342.135172-1-marmarek@invisiblethingslab.com
Eugene tripped over the case where rq_lock(), as called in a
for_each_possible_cpu() loop came apart because rq->core hadn't been
setup yet.
This is a somewhat unusual, but valid case.
Rework things such that rq->core is initialized to point at itself. IOW
initialize each CPU as a single threaded Core. CPU online will then join
the new CPU (thread) to an existing Core where needed.
For completeness sake, have CPU offline fully undo the state so as to
not presume the topology will match the next time it comes online.
Fixes: 9edeaea1bc45 ("sched: Core-wide rq->lock")
Reported-by: Eugene Syromiatnikov <esyr@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Josh Don <joshdon@google.com>
Tested-by: Eugene Syromiatnikov <esyr@redhat.com>
Link: https://lkml.kernel.org/r/YR473ZGeKqMs6kw+@hirez.programming.kicks-ass.net
The earlycon depends on the bootloader setup UART clocks being retained.
There're actually two uart clocks (ipg, per) on MX6QDL,
but the 'Fixes' commit change to register only one which means
another clock may be disabled during booting phase
and result in the earlycon unwork.
Cc: stable@vger.kernel.org # v5.10+
Fixes: 379c9a24cc23 ("clk: imx: Fix reparenting of UARTs not associated with stdout")
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Link: https://lore.kernel.org/r/20210702085438.1988087-1-aisheng.dong@nxp.com
Reviewed-by: Abel Vesa <abel.vesa@nxp.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Pull x86 fixes from Borislav Petkov:
- Fix build error on RHEL where -Werror=maybe-uninitialized is set.
- Restore the firmware's IDT when calling EFI boot services and before
ExitBootServices() has been called. This fixes a boot failure on what
appears to be a tablet with 32-bit UEFI running a 64-bit kernel.
* tag 'x86_urgent_for_v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/resctrl: Fix a maybe-uninitialized build warning treated as error
x86/efi: Restore Firmware IDT before calling ExitBootServices()
Assign pmu.module so the driver can't be unloaded whilst in use.
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210817221048.88063-4-kim.phillips@amd.com
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