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When updating the affinity of a VPE, the VMOVP command is currently skipped
if the two CPUs are part of the same VPE affinity.
But this is wrong, as the doorbell corresponding to this VPE is still
delivered on the 'old' CPU, which screws up the balancing. Furthermore,
offlining that 'old' CPU results in doorbell interrupts generated for this
VPE being discarded.
The harsh reality is that VMOVP cannot be elided when a set_affinity()
request occurs. It needs to be obeyed, and if an optimisation is to be
made, it is at the point where the affinity change request is made (such as
in KVM).
Drop the VMOVP elision altogether, and only use the vpe_table_mask
to try and stay within the same ITS affinity group if at all possible.
Fixes: dd3f050a216e (irqchip/gic-v4.1: Implement the v4.1 flavour of VMOVP)
Reported-by: Kunkun Jiang <jiangkunkun@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240213101206.2137483-4-maz@kernel.org
While refactoring the way the ITSs are probed, the handling of quirks
applicable to ACPI-based platforms was lost. As a result, systems such as
HIP07 lose their GICv4 functionnality, and some other may even fail to
boot, unless they are configured to boot with DT.
Move the enabling of quirks into its_probe_one(), making it common to all
firmware implementations.
Fixes: 9585a495ac93 ("irqchip/gic-v3-its: Split allocation from initialisation of its_node")
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240213101206.2137483-3-maz@kernel.org
Although the GICv3 code base has gained some handling of systems failing to
handle the shareability attributes, the GICv4 side of things has been
firmly ignored.
This is unfortunate, as the new recent addition of the "dma-noncoherent" is
supposed to apply to all of the GICR tables, and not just the ones that are
common to v3 and v4.
Add some checks to handle the VPROPBASE/VPENDBASE shareability and
cacheability attributes in the same way we deal with the other GICR_BASE
registers, wrapping the flag check in a helper for improved readability.
Note that this has been found by inspection only, as I don't have access to
HW that suffers from this particular issue.
Fixes: 3a0fff0fb6a3 ("irqchip/gic-v3: Enable non-coherent redistributors/ITSes DT probing")
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Link: https://lore.kernel.org/r/20240213101206.2137483-2-maz@kernel.org
devm_ioremap() doesn't return error pointers, it returns NULL on error.
Update the check accordingly.
Fixes: 221b110d87c2 ("irqchip/qcom-mpm: Support passing a slice of SRAM as reg space")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Link: https://lore.kernel.org/r/22e1f4de-edce-4791-bd2d-2b2e98529492@moroto.mountain
eiointc_domain_alloc() uses struct eiointc, which is not defined, for a
pointer. Older compilers treat that as a forward declaration and due to
assignment of a void pointer there is no warning emitted. As the variable
is then handed in as a void pointer argument to irq_domain_set_info() the
code is functional.
Use struct eiointc_priv instead.
[ tglx: Rewrote changelog ]
Fixes: dd281e1a1a93 ("irqchip: Add Loongson Extended I/O interrupt controller support")
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Huacai Chen <chenhuacai@loongson.cn>
Link: https://lore.kernel.org/r/20240130082722.2912576-2-maobibo@loongson.cn
It was observed on Broadcom devices that use GIC v3 architecture L1
interrupt controllers as the parent of brcmstb-l2 interrupt controllers
that the deactivation of the parent interrupt could happen before the
brcmstb-l2 deasserted its output. This would lead the GIC to reactivate the
interrupt only to find that no L2 interrupt was pending. The result was a
spurious interrupt invoking handle_bad_irq() with its associated
messaging. While this did not create a functional problem it is a waste of
cycles.
The hazard exists because the memory mapped bus writes to the brcmstb-l2
registers are buffered and the GIC v3 architecture uses a very efficient
system register write to deactivate the interrupt.
Add a write memory barrier prior to invoking chained_irq_exit() to
introduce a dsb(st) on those systems to ensure the system register write
cannot be executed until the memory mapped writes are visible to the
system.
[ florian: Added Fixes tag ]
Fixes: 7f646e92766e ("irqchip: brcmstb-l2: Add Broadcom Set Top Box Level-2 interrupt controller")
Signed-off-by: Doug Berger <opendmb@gmail.com>
Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Florian Fainelli <florian.fainelli@broadcom.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240210012449.3009125-1-florian.fainelli@broadcom.com
Pull timer fix from Borislav Petkov:
- Make sure a warning is issued when a hrtimer gets queued after the
timers have been migrated on the CPU down path and thus said timer
will get ignored
* tag 'timers_urgent_for_v6.8_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
hrtimer: Report offline hrtimer enqueue
Pull x86 fixes from Borislav Petkov:
- Correct the minimum CPU family for Transmeta Crusoe in Kconfig so
that such hw can boot again
- Do not take into accout XSTATE buffer size info supplied by userspace
when constructing a sigreturn frame
- Switch get_/put_user* to EX_TYPE_UACCESS exception handling when an
MCE is encountered so that it can be properly recovered from instead
of simply panicking
* tag 'x86_urgent_for_v6.8_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/Kconfig: Transmeta Crusoe is CPU family 5, not 6
x86/fpu: Stop relying on userspace for info to fault in xsave buffer
x86/lib: Revert to _ASM_EXTABLE_UA() for {get,put}_user() fixups
The hrtimers migration on CPU-down hotplug process has been moved
earlier, before the CPU actually goes to die. This leaves a small window
of opportunity to queue an hrtimer in a blind spot, leaving it ignored.
For example a practical case has been reported with RCU waking up a
SCHED_FIFO task right before the CPUHP_AP_IDLE_DEAD stage, queuing that
way a sched/rt timer to the local offline CPU.
Make sure such situations never go unnoticed and warn when that happens.
Fixes: 5c0930ccaad5 ("hrtimers: Push pending hrtimers away from outgoing CPU earlier")
Reported-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240129235646.3171983-4-boqun.feng@gmail.com
Pull misc fixes from Andrew Morton:
"21 hotfixes. 12 are cc:stable and the remainder pertain to post-6.7
issues or aren't considered to be needed in earlier kernel versions"
* tag 'mm-hotfixes-stable-2024-02-10-11-16' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (21 commits)
nilfs2: fix potential bug in end_buffer_async_write
mm/damon/sysfs-schemes: fix wrong DAMOS tried regions update timeout setup
nilfs2: fix hang in nilfs_lookup_dirty_data_buffers()
MAINTAINERS: Leo Yan has moved
mm/zswap: don't return LRU_SKIP if we have dropped lru lock
fs,hugetlb: fix NULL pointer dereference in hugetlbs_fill_super
mailmap: switch email address for John Moon
mm: zswap: fix objcg use-after-free in entry destruction
mm/madvise: don't forget to leave lazy MMU mode in madvise_cold_or_pageout_pte_range()
arch/arm/mm: fix major fault accounting when retrying under per-VMA lock
selftests: core: include linux/close_range.h for CLOSE_RANGE_* macros
mm/memory-failure: fix crash in split_huge_page_to_list from soft_offline_page
mm: memcg: optimize parent iteration in memcg_rstat_updated()
nilfs2: fix data corruption in dsync block recovery for small block sizes
mm/userfaultfd: UFFDIO_MOVE implementation should use ptep_get()
exit: wait_task_zombie: kill the no longer necessary spin_lock_irq(siglock)
fs/proc: do_task_stat: use sig->stats_lock to gather the threads/children stats
fs/proc: do_task_stat: move thread_group_cputime_adjusted() outside of lock_task_sighand()
getrusage: use sig->stats_lock rather than lock_task_sighand()
getrusage: move thread_group_cputime_adjusted() outside of lock_task_sighand()
...
The kernel built with MCRUSOE is unbootable on Transmeta Crusoe. It shows
the following error message:
This kernel requires an i686 CPU, but only detected an i586 CPU.
Unable to boot - please use a kernel appropriate for your CPU.
Remove MCRUSOE from the condition introduced in commit in Fixes, effectively
changing X86_MINIMUM_CPU_FAMILY back to 5 on that machine, which matches the
CPU family given by CPUID.
[ bp: Massage commit message. ]
Fixes: 25d76ac88821 ("x86/Kconfig: Explicitly enumerate i686-class CPUs in Kconfig")
Signed-off-by: Aleksander Mazur <deweloper@wp.pl>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/20240123134309.1117782-1-deweloper@wp.pl
Pull block fixes from Jens Axboe:
- NVMe pull request via Keith:
- Update a potentially stale firmware attribute (Maurizio)
- Fixes for the recent verbose error logging (Keith, Chaitanya)
- Protection information payload size fix for passthrough (Francis)
- Fix for a queue freezing issue in virtblk (Yi)
- blk-iocost underflow fix (Tejun)
- blk-wbt task detection fix (Jan)
* tag 'block-6.8-2024-02-10' of git://git.kernel.dk/linux:
virtio-blk: Ensure no requests in virtqueues before deleting vqs.
blk-iocost: Fix an UBSAN shift-out-of-bounds warning
nvme: use ns->head->pi_size instead of t10_pi_tuple structure size
nvme-core: fix comment to reflect right functions
nvme: move passthrough logging attribute to head
blk-wbt: Fix detection of dirty-throttled tasks
nvme-host: fix the updating of the firmware version
According to a syzbot report, end_buffer_async_write(), which handles the
completion of block device writes, may detect abnormal condition of the
buffer async_write flag and cause a BUG_ON failure when using nilfs2.
Nilfs2 itself does not use end_buffer_async_write(). But, the async_write
flag is now used as a marker by commit 7f42ec394156 ("nilfs2: fix issue
with race condition of competition between segments for dirty blocks") as
a means of resolving double list insertion of dirty blocks in
nilfs_lookup_dirty_data_buffers() and nilfs_lookup_node_buffers() and the
resulting crash.
This modification is safe as long as it is used for file data and b-tree
node blocks where the page caches are independent. However, it was
irrelevant and redundant to also introduce async_write for segment summary
and super root blocks that share buffers with the backing device. This
led to the possibility that the BUG_ON check in end_buffer_async_write
would fail as described above, if independent writebacks of the backing
device occurred in parallel.
The use of async_write for segment summary buffers has already been
removed in a previous change.
Fix this issue by removing the manipulation of the async_write flag for
the remaining super root block buffer.
Link: https://lkml.kernel.org/r/20240203161645.4992-1-konishi.ryusuke@gmail.com
Fixes: 7f42ec394156 ("nilfs2: fix issue with race condition of competition between segments for dirty blocks")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+5c04210f7c7f897c1e7f@syzkaller.appspotmail.com
Closes: https://lkml.kernel.org/r/00000000000019a97c05fd42f8c8@google.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>