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Linux kernel
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We just sorted the entries and fields last release, so just out of a
perverse sense of curiosity, I decided to see if we can keep things
ordered for even just one release.
The answer is "No. No we cannot".
I suggest that all kernel developers will need weekly training sessions,
involving a lot of Big Bird and Sesame Street. And at the yearly
maintainer summit, we will all sing the alphabet song together.
I doubt I will keep doing this. At some point "perverse sense of
curiosity" turns into just a cold dark place filled with sadness and
despair.
Repeats: 80e62bc8487b ("MAINTAINERS: re-sort all entries and fields")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull dma-mapping fixes from Christoph Hellwig:
- swiotlb area sizing fixes (Petr Tesarik)
* tag 'dma-mapping-6.5-2023-07-09' of git://git.infradead.org/users/hch/dma-mapping:
swiotlb: reduce the number of areas to match actual memory pool size
swiotlb: always set the number of areas before allocating the pool
Pull irq update from Borislav Petkov:
- Optimize IRQ domain's name assignment
* tag 'irq_urgent_for_v6.5_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqdomain: Use return value of strreplace()
Although the desired size of the SWIOTLB memory pool is increased in
swiotlb_adjust_nareas() to match the number of areas, the actual allocation
may be smaller, which may require reducing the number of areas.
For example, Xen uses swiotlb_init_late(), which in turn uses the page
allocator. On x86, page size is 4 KiB and MAX_ORDER is 10 (1024 pages),
resulting in a maximum memory pool size of 4 MiB. This corresponds to 2048
slots of 2 KiB each. The minimum area size is 128 (IO_TLB_SEGSIZE),
allowing at most 2048 / 128 = 16 areas.
If num_possible_cpus() is greater than the maximum number of areas, areas
are smaller than IO_TLB_SEGSIZE and contiguous groups of free slots will
span multiple areas. When allocating and freeing slots, only one area will
be properly locked, causing race conditions on the unlocked slots and
ultimately data corruption, kernel hangs and crashes.
Fixes: 20347fca71a3 ("swiotlb: split up the global swiotlb lock")
Signed-off-by: Petr Tesarik <petr.tesarik.ext@huawei.com>
Reviewed-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Pull x86 fpu fix from Borislav Petkov:
- Do FPU AP initialization on Xen PV too which got missed by the recent
boot reordering work
* tag 'x86_urgent_for_v6.5_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/xen: Fix secondary processors' FPU initialization
Since strreplace() returns the pointer to the string itself, use it
directly.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230628150251.17832-1-andriy.shevchenko@linux.intel.com
The number of areas defaults to the number of possible CPUs. However, the
total number of slots may have to be increased after adjusting the number
of areas. Consequently, the number of areas must be determined before
allocating the memory pool. This is even explained with a comment in
swiotlb_init_remap(), but swiotlb_init_late() adjusts the number of areas
after slots are already allocated. The areas may end up being smaller than
IO_TLB_SEGSIZE, which breaks per-area locking.
While fixing swiotlb_init_late(), move all relevant comments before the
definition of swiotlb_adjust_nareas() and convert them to kernel-doc.
Fixes: 20347fca71a3 ("swiotlb: split up the global swiotlb lock")
Signed-off-by: Petr Tesarik <petr.tesarik.ext@huawei.com>
Reviewed-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Pull x86 fix from Thomas Gleixner:
"A single fix for the mechanism to park CPUs with an INIT IPI.
On shutdown or kexec, the kernel tries to park the non-boot CPUs with
an INIT IPI. But the same code path is also used by the crash utility.
If the CPU which panics is not the boot CPU then it sends an INIT IPI
to the boot CPU which resets the machine.
Prevent this by validating that the CPU which runs the stop mechanism
is the boot CPU. If not, leave the other CPUs in HLT"
* tag 'x86-core-2023-07-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/smp: Don't send INIT to boot CPU
Moving the call of fpu__init_cpu() from cpu_init() to start_secondary()
broke Xen PV guests, as those don't call start_secondary() for APs.
Call fpu__init_cpu() in Xen's cpu_bringup(), which is the Xen PV
replacement of start_secondary().
Fixes: b81fac906a8f ("x86/fpu: Move FPU initialization into arch_cpu_finalize_init()")
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230703130032.22916-1-jgross@suse.com
Pull irq updates from Thomas Gleixner:
"Updates for the interrupt subsystem:
Core:
- Convert the interrupt descriptor storage to a maple tree to
overcome the limitations of the radixtree + fixed size bitmap.
This allows us to handle very large servers with a huge number of
guests without imposing a huge memory overhead on everyone
- Implement optional retriggering of interrupts which utilize the
fasteoi handler to work around a GICv3 architecture issue
Drivers:
- A set of fixes and updates for the Loongson/Loongarch related
drivers
- Workaound for an ASR8601 integration hickup which ends up with CPU
numbering which can't be represented in the GIC implementation
- The usual set of boring fixes and updates all over the place"
* tag 'irq-core-2023-06-26' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits)
Revert "irqchip/mxs: Include linux/irqchip/mxs.h"
irqchip/jcore-aic: Fix missing allocation of IRQ descriptors
irqchip/stm32-exti: Fix warning on initialized field overwritten
irqchip/stm32-exti: Add STM32MP15xx IWDG2 EXTI to GIC map
irqchip/gicv3: Add a iort_pmsi_get_dev_id() prototype
irqchip/mxs: Include linux/irqchip/mxs.h
irqchip/clps711x: Remove unused clps711x_intc_init() function
irqchip/mmp: Remove non-DT codepath
irqchip/ftintc010: Mark all function static
irqdomain: Include internals.h for function prototypes
irqchip/loongson-eiointc: Add DT init support
dt-bindings: interrupt-controller: Add Loongson EIOINTC
irqchip/loongson-eiointc: Fix irq affinity setting during resume
irqchip/loongson-liointc: Add IRQCHIP_SKIP_SET_WAKE flag
irqchip/loongson-liointc: Fix IRQ trigger polarity
irqchip/loongson-pch-pic: Fix potential incorrect hwirq assignment
irqchip/loongson-pch-pic: Fix initialization of HT vector register
irqchip/gic-v3-its: Enable RESEND_WHEN_IN_PROGRESS for LPIs
genirq: Allow fasteoi handler to resend interrupts on concurrent handling
genirq: Expand doc for PENDING and REPLAY flags
...
Drivers have no business looking into dma-mapping internals and check
what backend is used. Unfortunstely the DRM core is still broken and
tries to do plain page allocations instead of using DMA API allocators
by default and uses various bandaids on when to use dma_alloc_coherent.
Switch nouveau to use the same (broken) scheme as amdgpu and radeon
to remove the last driver user of is_swiotlb_active.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Pull MIPS fixes from Thomas Bogendoerfer:
- fixes for KVM
- fix for loongson build and cpu probing
- DT fixes
* tag 'mips_6.5_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
MIPS: kvm: Fix build error with KVM_MIPS_DEBUG_COP0_COUNTERS enabled
MIPS: dts: add missing space before {
MIPS: Loongson: Fix build error when make modules_install
MIPS: KVM: Fix NULL pointer dereference
MIPS: Loongson: Fix cpu_probe_loongson() again
Parking CPUs in INIT works well, except for the crash case when the CPU
which invokes smp_park_other_cpus_in_init() is not the boot CPU. Sending
INIT to the boot CPU resets the whole machine.
Prevent this by validating that this runs on the boot CPU. If not fall back
and let CPUs hang in HLT.
Fixes: 45e34c8af58f ("x86/smp: Put CPUs into INIT on shutdown if possible")
Reported-by: Baokun Li <libaokun1@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Baokun Li <libaokun1@huawei.com>
Link: https://lore.kernel.org/r/87ttui91jo.ffs@tglx
Niklāvs reported a boot regression on an Alderlake machine and bisected it
to commit 9df9d2f0471b ("init: Invoke arch_cpu_finalize_init() earlier").
By moving the invocation of arch_cpu_finalize_init() further down he
identified that efi_enter_virtual_mode() is the function which causes the
boot hang.
The main difference of the earlier invocation is that the boot CPU is
already fully initialized and mitigations and alternatives are applied.
But the only really interesting change turned out to be IBT, which is now
enabled before efi_enter_virtual_mode(). "ibt=off" on the kernel command
line cured the problem.
Inspection of the involved calls in efi_enter_virtual_mode() unearthed that
efi_set_virtual_address_map() is the only place in the kernel which invokes
an EFI call without the IBT safe wrapper. This went obviously unnoticed so
far as IBT was enabled later.
Use arch_efi_call_virt() instead of efi_call() to cure that.
Fixes: fe379fa4d199 ("x86/ibt: Disable IBT around firmware")
Fixes: 9df9d2f0471b ("init: Invoke arch_cpu_finalize_init() earlier")
Reported-by: Niklāvs Koļesņikovs <pinkflames.linux@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217602
Link: https://lore.kernel.org/r/87jzvm12q0.ffs@tglx
Pull debugobjects update from Thomas Gleixner:
"A single update for debug objects:
- Recheck whether debug objects is enabled before reporting a problem
to avoid spamming the logs with messages which are caused by a
concurrent OOM"
* tag 'core-debugobjects-2023-06-26' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip:
debugobjects: Recheck debug_objects_enabled before reporting
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