Allow more pools can be shared when attrs->affn_strict.
Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

dead_work is a stack variable.
Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Now that work_grab_pending() can always grab the PENDING bit without
sleeping, the only thing that prevents allowing cancel_work_sync() of a BH
work item from an atomic context is the flushing of the in-flight instance.

When we're flushing a BH work item for cancel_work_sync(), we know that the
work item is not queued and must be executing in a BH context, which means
that it's safe to busy-wait for its completion from a non-hardirq atomic
context.

This patch updates __flush_work() so that it busy-waits when flushing a BH
work item for cancel_work_sync(). might_sleep() is pushed from
start_flush_work() to its callers - when operating on a BH work item,
__cancel_work_sync() now enforces !in_hardirq() instead of might_sleep().

This allows cancel_work_sync() and disable_work() to be called from
non-hardirq atomic contexts on BH work items.

v3: In __flush_work(), test WORK_OFFQ_BH to tell whether a work item being
    canceled can be busy waited instead of making start_flush_work() return
    the pool. (Lai)

v2: Lai pointed out that __flush_work() was accessing pool->flags outside
    the RCU critical section protecting the pool pointer. Fix it by testing
    and remembering the result inside the RCU critical section.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>

Add an off-queue flag, WORK_OFFQ_BH, that indicates whether the last
workqueue the work item was on was a BH one. This will be used to test
whether a work item is BH in cancel_sync path to implement atomic
cancel_sync'ing for BH work items.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>

cancel[_delayed]_work_sync() guarantees that it can shut down
self-requeueing work items. To achieve that, it grabs and then holds
WORK_STRUCT_PENDING bit set while flushing the currently executing instance.
As the PENDING bit is set, all queueing attempts including the
self-requeueing ones fail and once the currently executing instance is
flushed, the work item should be idle as long as someone else isn't actively
queueing it.

This means that the cancel_work_sync path may hold the PENDING bit set while
flushing the target work item. This isn't a problem for the queueing path -
it can just fail which is the desired effect. It doesn't affect flush. It
doesn't matter to cancel_work either as it can just report that the work
item has successfully canceled. However, if there's another cancel_work_sync
attempt on the work item, it can't simply fail or report success and that
would breach the guarantee that it should provide. cancel_work_sync has to
wait for and grab that PENDING bit and go through the motions.

WORK_OFFQ_CANCELING and wq_cancel_waitq are what implement this
cancel_work_sync to cancel_work_sync wait mechanism. When a work item is
being canceled, WORK_OFFQ_CANCELING is also set on it and other
cancel_work_sync attempts wait on the bit to be cleared using the wait
queue.

While this works, it's an isolated wart which doesn't jive with the rest of
flush and cancel mechanisms and forces enable_work() and disable_work() to
require a sleepable context, which hampers their usability.

Now that a work item can be disabled, we can use that to block queueing
while cancel_work_sync is in progress. Instead of holding PENDING the bit,
it can temporarily disable the work item, flush and then re-enable it as
that'd achieve the same end result of blocking queueings while canceling and
thus enable canceling of self-requeueing work items.

- WORK_OFFQ_CANCELING and the surrounding mechanims are removed.

- work_grab_pending() is now simpler, no longer has to wait for a blocking
  operation and thus can be called from any context.

- With work_grab_pending() simplified, no need to use try_to_grab_pending()
  directly. All users are converted to use work_grab_pending().

- __cancel_work_sync() is updated to __cancel_work() with
  WORK_CANCEL_DISABLE to cancel and plug racing queueing attempts. It then
  flushes and re-enables the work item if necessary.

- These changes allow disable_work() and enable_work() to be called from any
  context.

v2: Lai pointed out that mod_delayed_work_on() needs to check the disable
    count before queueing the delayed work item. Added
    clear_pending_if_disabled() call.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>

While (delayed) work items could be flushed and canceled, there was no way
to prevent them from being queued in the future. While this didn't lead to
functional deficiencies, it sometimes required a bit more effort from the
workqueue users to e.g. sequence shutdown steps with more care.

Workqueue is currently in the process of replacing tasklet which does
support disabling and enabling. The feature is used relatively widely to,
for example, temporarily suppress main path while a control plane operation
(reset or config change) is in progress.

To enable easy conversion of tasklet users and as it seems like an inherent
useful feature, this patch implements disabling and enabling of work items.

- A work item carries 16bit disable count in work->data while not queued.
  The access to the count is synchronized by the PENDING bit like all other
  parts of work->data.

- If the count is non-zero, the work item cannot be queued. Any attempt to
  queue the work item fails and returns %false.

- disable_work[_sync](), enable_work(), disable_delayed_work[_sync]() and
  enable_delayed_work() are added.

v3: enable_work() was using local_irq_enable() instead of
    local_irq_restore() to undo IRQ-disable by work_grab_pending(). This is
    awkward now and will become incorrect as enable_work() will later be
    used from IRQ context too. (Lai)

v2: Lai noticed that queue_work_node() wasn't checking the disable count.
    Fixed. queue_rcu_work() is updated to trigger warning if the inner work
    item is disabled.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>

The cancel[_sync] paths acquire and release WORK_STRUCT_PENDING, and
manipulate WORK_OFFQ_CANCELING. However, they assume that all the OFFQ bit
values except for the pool ID are statically known and don't preserve them,
which is not wrong in the current code as the pool ID and CANCELING are the
only information carried. However, the planned disable/enable support will
add more fields and need them to be preserved.

This patch updates work data handling so that only the bits which need
updating are updated.

- struct work_offq_data is added along with work_offqd_unpack() and
  work_offqd_pack_flags() to help manipulating multiple fields contained in
  work->data. Note that the helpers look a bit silly right now as there
  isn't that much to pack. The next patch will add more.

- mark_work_canceling() which is used only by __cancel_work_sync() is
  replaced by open-coded usage of work_offq_data and
  set_work_pool_and_keep_pending() in __cancel_work_sync().

- __cancel_work[_sync]() uses offq_data helpers to preserve other OFFQ bits
  when clearing WORK_STRUCT_PENDING and WORK_OFFQ_CANCELING at the end.

- This removes all users of get_work_pool_id() which is dropped. Note that
  get_work_pool_id() could handle both WORK_STRUCT_PWQ and !WORK_STRUCT_PWQ
  cases; however, it was only being called after try_to_grab_pending()
  succeeded, in which case WORK_STRUCT_PWQ is never set and thus it's safe
  to use work_offqd_unpack() instead.

No behavior changes intended.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>

Pull EFI fixes from Ard Biesheuvel:

 - Fix logic that is supposed to prevent placement of the kernel image
   below LOAD_PHYSICAL_ADDR

 - Use the firmware stack in the EFI stub when running in mixed mode

 - Clear BSS only once when using mixed mode

 - Check efi.get_variable() function pointer for NULL before trying to
   call it

* tag 'efi-fixes-for-v6.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
  efi: fix panic in kdump kernel
  x86/efistub: Don't clear BSS twice in mixed mode
  x86/efistub: Call mixed mode boot services on the firmware's stack
  efi/libstub: fix efi_random_alloc() to allocate memory at alloc_min or higher address

Pull x86 fixes from Thomas Gleixner:

 - Ensure that the encryption mask at boot is properly propagated on
   5-level page tables, otherwise the PGD entry is incorrectly set to
   non-encrypted, which causes system crashes during boot.

 - Undo the deferred 5-level page table setup as it cannot work with
   memory encryption enabled.

 - Prevent inconsistent XFD state on CPU hotplug, where the MSR is reset
   to the default value but the cached variable is not, so subsequent
   comparisons might yield the wrong result and as a consequence the
   result prevents updating the MSR.

 - Register the local APIC address only once in the MPPARSE enumeration
   to prevent triggering the related WARN_ONs() in the APIC and topology
   code.

 - Handle the case where no APIC is found gracefully by registering a
   fake APIC in the topology code. That makes all related topology
   functions work correctly and does not affect the actual APIC driver
   code at all.

 - Don't evaluate logical IDs during early boot as the local APIC IDs
   are not yet enumerated and the invoked function returns an error
   code. Nothing requires the logical IDs before the final CPUID
   enumeration takes place, which happens after the enumeration.

 - Cure the fallout of the per CPU rework on UP which misplaced the
   copying of boot_cpu_data to per CPU data so that the final update to
   boot_cpu_data got lost which caused inconsistent state and boot
   crashes.

 - Use copy_from_kernel_nofault() in the kprobes setup as there is no
   guarantee that the address can be safely accessed.

 - Reorder struct members in struct saved_context to work around another
   kmemleak false positive

 - Remove the buggy code which tries to update the E820 kexec table for
   setup_data as that is never passed to the kexec kernel.

 - Update the resource control documentation to use the proper units.

 - Fix a Kconfig warning observed with tinyconfig

* tag 'x86-urgent-2024-03-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot/64: Move 5-level paging global variable assignments back
  x86/boot/64: Apply encryption mask to 5-level pagetable update
  x86/cpu: Add model number for another Intel Arrow Lake mobile processor
  x86/fpu: Keep xfd_state in sync with MSR_IA32_XFD
  Documentation/x86: Document that resctrl bandwidth control units are MiB
  x86/mpparse: Register APIC address only once
  x86/topology: Handle the !APIC case gracefully
  x86/topology: Don't evaluate logical IDs during early boot
  x86/cpu: Ensure that CPU info updates are propagated on UP
  kprobes/x86: Use copy_from_kernel_nofault() to read from unsafe address
  x86/pm: Work around false positive kmemleak report in msr_build_context()
  x86/kexec: Do not update E820 kexec table for setup_data
  x86/config: Fix warning for 'make ARCH=x86_64 tinyconfig'

Pull scheduler doc clarification from Thomas Gleixner:
 "A single update for the documentation of the base_slice_ns tunable to
  clarify that any value which is less than the tick slice has no effect
  because the scheduler tick is not guaranteed to happen within the set
  time slice"

* tag 'sched-urgent-2024-03-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/doc: Update documentation for base_slice_ns and CONFIG_HZ relation

Pull dma-mapping fixes from Christoph Hellwig:
 "This has a set of swiotlb alignment fixes for sometimes very long
  standing bugs from Will. We've been discussion them for a while and
  they should be solid now"

* tag 'dma-mapping-6.9-2024-03-24' of git://git.infradead.org/users/hch/dma-mapping:
  swiotlb: Reinstate page-alignment for mappings >= PAGE_SIZE
  iommu/dma: Force swiotlb_max_mapping_size on an untrusted device
  swiotlb: Fix alignment checks when both allocation and DMA masks are present
  swiotlb: Honour dma_alloc_coherent() alignment in swiotlb_alloc()
  swiotlb: Enforce page alignment in swiotlb_alloc()
  swiotlb: Fix double-allocation of slots due to broken alignment handling

Check if get_next_variable() is actually valid pointer before
calling it. In kdump kernel this method is set to NULL that causes
panic during the kexec-ed kernel boot.

Tested with QEMU and OVMF firmware.

Fixes: bad267f9 ("efi: verify that variable services are supported")
Signed-off-by: Oleksandr Tymoshenko <ovt@google.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Clearing BSS should only be done once, at the very beginning.
efi_pe_entry() is the entrypoint from the firmware, which may not clear
BSS and so it is done explicitly. However, efi_pe_entry() is also used
as an entrypoint by the mixed mode startup code, in which case BSS will
already have been cleared, and doing it again at this point will corrupt
global variables holding the firmware's GDT/IDT and segment selectors.

So make the memset() conditional on whether the EFI stub is running in
native mode.

Fixes: b3810c5a ("x86/efistub: Clear decompressor BSS in native EFI entrypoint")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Normally, the EFI stub calls into the EFI boot services using the stack
that was live when the stub was entered. According to the UEFI spec,
this stack needs to be at least 128k in size - this might seem large but
all asynchronous processing and event handling in EFI runs from the same
stack and so quite a lot of space may be used in practice.

In mixed mode, the situation is a bit different: the bootloader calls
the 32-bit EFI stub entry point, which calls the decompressor's 32-bit
entry point, where the boot stack is set up, using a fixed allocation
of 16k. This stack is still in use when the EFI stub is started in
64-bit mode, and so all calls back into the EFI firmware will be using
the decompressor's limited boot stack.

Due to the placement of the boot stack right after the boot heap, any
stack overruns have gone unnoticed. However, commit

  5c4feadb0011983b ("x86/decompressor: Move global symbol references to C code")

moved the definition of the boot heap into C code, and now the boot
stack is placed right at the base of BSS, where any overruns will
corrupt the end of the .data section.

While it would be possible to work around this by increasing the size of
the boot stack, doing so would affect all x86 systems, and mixed mode
systems are a tiny (and shrinking) fraction of the x86 installed base.

So instead, record the firmware stack pointer value when entering from
the 32-bit firmware, and switch to this stack every time a EFI boot
service call is made.

Cc: <stable@kernel.org> # v6.1+
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Commit 63bed966 ("x86/startup_64: Defer assignment of 5-level paging
global variables") moved assignment of 5-level global variables to later
in the boot in order to avoid having to use RIP relative addressing in
order to set them. However, when running with 5-level paging and SME
active (mem_encrypt=on), the variables are needed as part of the page
table setup needed to encrypt the kernel (using pgd_none(), p4d_offset(),
etc.). Since the variables haven't been set, the page table manipulation
is done as if 4-level paging is active, causing the system to crash on
boot.

While only a subset of the assignments that were moved need to be set
early, move all of the assignments back into check_la57_support() so that
these assignments aren't spread between two locations. Instead of just
reverting the fix, this uses the new RIP_REL_REF() macro when assigning
the variables.

Fixes: 63bed966 ("x86/startup_64: Defer assignment of 5-level paging global variables")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/2ca419f4d0de719926fd82353f6751f717590a86.1711122067.git.thomas.lendacky@amd.com

When running with 5-level page tables, the kernel mapping PGD entry is
updated to point to the P4D table. The assignment uses _PAGE_TABLE_NOENC,
which, when SME is active (mem_encrypt=on), results in a page table
entry without the encryption mask set, causing the system to crash on
boot.

Change the assignment to use _PAGE_TABLE instead of _PAGE_TABLE_NOENC so
that the encryption mask is set for the PGD entry.

Fixes: 533568e0 ("x86/boot/64: Use RIP_REL_REF() to access early_top_pgt[]")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/8f20345cda7dbba2cf748b286e1bc00816fe649a.1711122067.git.thomas.lendacky@amd.com

This one is the regular laptop CPU.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240322161725.195614-1-tony.luck@intel.com

Commit 67236547 ("x86/fpu: Update XFD state where required") and
commit 8bf26758 ("x86/fpu: Add XFD state to fpstate") introduced a
per CPU variable xfd_state to keep the MSR_IA32_XFD value cached, in
order to avoid unnecessary writes to the MSR.

On CPU hotplug MSR_IA32_XFD is reset to the init_fpstate.xfd, which
wipes out any stale state. But the per CPU cached xfd value is not
reset, which brings them out of sync.

As a consequence a subsequent xfd_update_state() might fail to update
the MSR which in turn can result in XRSTOR raising a #NM in kernel
space, which crashes the kernel.

To fix this, introduce xfd_set_state() to write xfd_state together
with MSR_IA32_XFD, and use it in all places that set MSR_IA32_XFD.

Fixes: 67236547 ("x86/fpu: Update XFD state where required")
Signed-off-by: Adamos Ttofari <attofari@amazon.de>
Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240322230439.456571-1-chang.seok.bae@intel.com

Closes: https://lore.kernel.org/lkml/20230511152818.13839-1-attofari@amazon.de

The memory bandwidth software controller uses 2^20 units rather than
10^6. See mbm_bw_count() which computes bandwidth using the "SZ_1M"
Linux define for 0x00100000.

Update the documentation to use MiB when describing this feature.
It's too late to fix the mount option "mba_MBps" as that is now an
established user interface.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240322182016.196544-1-tony.luck@intel.com

Pull timer fixes from Thomas Gleixner:
 "Two regression fixes for the timer and timer migration code:

   - Prevent endless timer requeuing which is caused by two CPUs racing
     out of idle. This happens when the last CPU goes idle and therefore
     has to ensure to expire the pending global timers and some other
     CPU come out of idle at the same time and the other CPU wins the
     race and expires the global queue. This causes the last CPU to
     chase ghost timers forever and reprogramming it's clockevent device
     endlessly.

     Cure this by re-evaluating the wakeup time unconditionally.

   - The split into local (pinned) and global timers in the timer wheel
     caused a regression for NOHZ full as it broke the idle tracking of
     global timers. On NOHZ full this prevents an self IPI being sent
     which in turn causes the timer to be not programmed and not being
     expired on time.

     Restore the idle tracking for the global timer base so that the
     self IPI condition for NOHZ full is working correctly again"

* tag 'timers-urgent-2024-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timers: Fix removed self-IPI on global timer's enqueue in nohz_full
  timers/migration: Fix endless timer requeue after idle interrupts

Pull more clocksource updates from Thomas Gleixner:
 "A set of updates for clocksource and clockevent drivers:

   - A fix for the prescaler of the ARM global timer where the prescaler
     mask define only covered 4 bits while it is actully 8 bits wide.
     This obviously restricted the possible range of prescaler
     adjustments

   - A fix for the RISC-V timer which prevents a timer interrupt being
     raised while the timer is initialized

   - A set of device tree updates to support new system on chips in
     various drivers

   - Kernel-doc and other cleanups all over the place"

* tag 'timers-core-2024-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource/drivers/timer-riscv: Clear timer interrupt on timer initialization
  dt-bindings: timer: Add support for cadence TTC PWM
  clocksource/drivers/arm_global_timer: Simplify prescaler register access
  clocksource/drivers/arm_global_timer: Guard against division by zero
  clocksource/drivers/arm_global_timer: Make gt_target_rate unsigned long
  dt-bindings: timer: add Ralink SoCs system tick counter
  clocksource: arm_global_timer: fix non-kernel-doc comment
  clocksource/drivers/arm_global_timer: Remove stray tab
  clocksource/drivers/arm_global_timer: Fix maximum prescaler value
  clocksource/drivers/imx-sysctr: Add i.MX95 support
  clocksource/drivers/imx-sysctr: Drop use global variables
  dt-bindings: timer: nxp,sysctr-timer: support i.MX95
  dt-bindings: timer: renesas: ostm: Document RZ/Five SoC
  dt-bindings: timer: renesas,tmu: Document input capture interrupt
  clocksource/drivers/ti-32K: Fix misuse of "/**" comment
  clocksource/drivers/stm32: Fix all kernel-doc warnings
  dt-bindings: timer: exynos4210-mct: Add google,gs101-mct compatible
  clocksource/drivers/imx: Fix -Wunused-but-set-variable warning

Pull irq fixes from Thomas Gleixner:
 "A series of fixes for the Renesas RZG21 interrupt chip driver to
  prevent spurious and misrouted interrupts.

   - Ensure that posted writes are flushed in the eoi() callback

   - Ensure that interrupts are masked at the chip level when the
     trigger type is changed

   - Clear the interrupt status register when setting up edge type
     trigger modes

   - Ensure that the trigger type and routing information is set before
     the interrupt is enabled"

* tag 'irq-urgent-2024-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/renesas-rzg2l: Do not set TIEN and TINT source at the same time
  irqchip/renesas-rzg2l: Prevent spurious interrupts when setting trigger type
  irqchip/renesas-rzg2l: Rename rzg2l_irq_eoi()
  irqchip/renesas-rzg2l: Rename rzg2l_tint_eoi()
  irqchip/renesas-rzg2l: Flush posted write in irq_eoi()

Pull core entry fix from Thomas Gleixner:
 "A single fix for the generic entry code:

  The trace_sys_enter() tracepoint can modify the syscall number via
  kprobes or BPF in pt_regs, but that requires that the syscall number
  is re-evaluted from pt_regs after the tracepoint.

  A seccomp fix in that area removed the re-evaluation so the change
  does not take effect as the code just uses the locally cached number.

  Restore the original behaviour by re-evaluating the syscall number
  after the tracepoint"

* tag 'core-entry-2024-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  entry: Respect changes to system call number by trace_sys_enter()

Pull more powerpc updates from Michael Ellerman:

 - Handle errors in mark_rodata_ro() and mark_initmem_nx()

 - Make struct crash_mem available without CONFIG_CRASH_DUMP

Thanks to Christophe Leroy and Hari Bathini.

* tag 'powerpc-6.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/kdump: Split KEXEC_CORE and CRASH_DUMP dependency
  powerpc/kexec: split CONFIG_KEXEC_FILE and CONFIG_CRASH_DUMP
  kexec/kdump: make struct crash_mem available without CONFIG_CRASH_DUMP
  powerpc: Handle error in mark_rodata_ro() and mark_initmem_nx()

Pull ARM updates from Russell King:

 - remove a misuse of kernel-doc comment

 - use "Call trace:" for backtraces like other architectures

 - implement copy_from_kernel_nofault_allowed() to fix a LKDTM test

 - add a "cut here" line for prefetch aborts

 - remove unnecessary Kconfing entry for FRAME_POINTER

 - remove iwmmxy support for PJ4/PJ4B cores

 - use bitfield helpers in ptrace to improve readabililty

 - check if folio is reserved before flushing

* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: 9359/1: flush: check if the folio is reserved for no-mapping addresses
  ARM: 9354/1: ptrace: Use bitfield helpers
  ARM: 9352/1: iwmmxt: Remove support for PJ4/PJ4B cores
  ARM: 9353/1: remove unneeded entry for CONFIG_FRAME_POINTER
  ARM: 9351/1: fault: Add "cut here" line for prefetch aborts
  ARM: 9350/1: fault: Implement copy_from_kernel_nofault_allowed()
  ARM: 9349/1: unwind: Add missing "Call trace:" line
  ARM: 9334/1: mm: init: remove misuse of kernel-doc comment

Pull more hardening updates from Kees Cook:

 - CONFIG_MEMCPY_SLOW_KUNIT_TEST is no longer needed (Guenter Roeck)

 - Fix needless UTF-8 character in arch/Kconfig (Liu Song)

 - Improve __counted_by warning message in LKDTM (Nathan Chancellor)

 - Refactor DEFINE_FLEX() for default use of __counted_by

 - Disable signed integer overflow sanitizer on GCC < 8

* tag 'hardening-v6.9-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  lkdtm/bugs: Improve warning message for compilers without counted_by support
  overflow: Change DEFINE_FLEX to take __counted_by member
  Revert "kunit: memcpy: Split slow memcpy tests into MEMCPY_SLOW_KUNIT_TEST"
  arch/Kconfig: eliminate needless UTF-8 character in Kconfig help
  ubsan: Disable signed integer overflow sanitizer on GCC < 8

The APIC address is registered twice. First during the early detection and
afterwards when actually scanning the table for APIC IDs. The APIC and
topology core warn about the second attempt.

Restrict it to the early detection call.

Fixes: 81287ad6 ("x86/apic: Sanitize APIC address setup")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20240322185305.297774848@linutronix.de

If there is no local APIC enumerated and registered then the topology
bitmaps are empty. Therefore, topology_init_possible_cpus() will die with
a division by zero exception.

Prevent this by registering a fake APIC id to populate the topology
bitmap. This also allows to use all topology query interfaces
unconditionally. It does not affect the actual APIC code because either
the local APIC address was not registered or no local APIC could be
detected.

Fixes: f1f758a8 ("x86/topology: Add a mechanism to track topology via APIC IDs")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20240322185305.242709302@linutronix.de

The local APICs have not yet been enumerated so the logical ID evaluation
from the topology bitmaps does not work and would return an error code.

Skip the evaluation during the early boot CPUID evaluation and only apply
it on the final run.

Fixes: 380414be ("x86/cpu/topology: Use topology logical mapping mechanism")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20240322185305.186943142@linutronix.de

The boot sequence evaluates CPUID information twice:

  1) During early boot

  2) When finalizing the early setup right before
     mitigations are selected and alternatives are patched.

In both cases the evaluation is stored in boot_cpu_data, but on UP the
copying of boot_cpu_data to the per CPU info of the boot CPU happens
between #1 and #2. So any update which happens in #2 is never propagated to
the per CPU info instance.

Consolidate the whole logic and copy boot_cpu_data right before applying
alternatives as that's the point where boot_cpu_data is in it's final
state and not supposed to change anymore.

This also removes the voodoo mb() from smp_prepare_cpus_common() which
had absolutely no purpose.

Fixes: 71eb4893 ("x86/percpu: Cure per CPU madness on UP")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20240322185305.127642785@linutronix.de

The current message for telling the user that their compiler does not
support the counted_by attribute in the FAM_BOUNDS test does not make
much sense either grammatically or semantically. Fix it to make it
correct in both aspects.
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20240321-lkdtm-improve-lack-of-counted_by-msg-v1-1-0fbf7481a29c@kernel.orgSigned-off-by: Kees Cook <keescook@chromium.org>

The norm should be flexible array structures with __counted_by
annotations, so DEFINE_FLEX() is updated to expect that. Rename
the non-annotated version to DEFINE_RAW_FLEX(), and update the
few existing users. Additionally add selftests for the macros.
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20240306235128.it.933-kees@kernel.orgReviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Signed-off-by: Kees Cook <keescook@chromium.org>

Pull more SCSI updates from James Bottomley:
 "The vfs has long had a write lifetime hint mechanism that gives the
  expected longevity on storage of the data being written. f2fs was the
  original consumer of this and used the hint for flash data placement
  (mostly to avoid write amplification by placing objects with similar
  lifetimes in the same erase block).

  More recently the SCSI based UFS (Universal Flash Storage) drivers
  have wanted to take advantage of this as well, for the same reasons as
  f2fs, necessitating plumbing the write hints through the block layer
  and then adding it to the SCSI core.

  The vfs write_hints already taken plumbs this as far as block and this
  completes the SCSI core enabling based on a recently agreed reuse of
  the old write command group number. The additions to the scsi_debug
  driver are for emulating this property so we can run tests on it in
  the absence of an actual UFS device"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: scsi_debug: Maintain write statistics per group number
  scsi: scsi_debug: Implement GET STREAM STATUS
  scsi: scsi_debug: Implement the IO Advice Hints Grouping mode page
  scsi: scsi_debug: Allocate the MODE SENSE response from the heap
  scsi: scsi_debug: Rework subpage code error handling
  scsi: scsi_debug: Rework page code error handling
  scsi: scsi_debug: Support the block limits extension VPD page
  scsi: scsi_debug: Reduce code duplication
  scsi: sd: Translate data lifetime information
  scsi: scsi_proto: Add structures and constants related to I/O groups and streams
  scsi: core: Query the Block Limits Extension VPD page

Pull more block updates from Jens Axboe:

 - NVMe pull request via Keith:
     - Make an informative message less ominous (Keith)
     - Enhanced trace decoding (Guixin)
     - TCP updates (Hannes, Li)
     - Fabrics connect deadlock fix (Chunguang)
     - Platform API migration update (Uwe)
     - A new device quirk (Jiawei)

 - Remove dead assignment in fd (Yufeng)

* tag 'block-6.9-20240322' of git://git.kernel.dk/linux:
  nvmet-rdma: remove NVMET_RDMA_REQ_INVALIDATE_RKEY flag
  nvme: remove redundant BUILD_BUG_ON check
  floppy: remove duplicated code in redo_fd_request()
  nvme/tcp: Add wq_unbound modparam for nvme_tcp_wq
  nvme-tcp: Export the nvme_tcp_wq to sysfs
  drivers/nvme: Add quirks for device 126f:2262
  nvme: parse format command's lbafu when tracing
  nvme: add tracing of reservation commands
  nvme: parse zns command's zsa and zrasf to string
  nvme: use nvme_disk_is_ns_head helper
  nvme: fix reconnection fail due to reserved tag allocation
  nvmet: add tracing of zns commands
  nvmet: add tracing of authentication commands
  nvme-apple: Convert to platform remove callback returning void
  nvmet-tcp: do not continue for invalid icreq
  nvme: change shutdown timeout setting message

Pull more io_uring updates from Jens Axboe:
 "One patch just missed the initial pull, the rest are either fixes or
  small cleanups that make our life easier for the next kernel:

   - Fix a potential leak in error handling of pinned pages, and clean
     it up (Gabriel, Pavel)

   - Fix an issue with how read multishot returns retry (me)

   - Fix a problem with waitid/futex removals, if we hit the case of
     needing to remove all of them at exit time (me)

   - Fix for a regression introduced in this merge window, where we
     don't always have sr->done_io initialized if the ->prep_async()
     path is used (me)

   - Fix for SQPOLL setup error handling (me)

   - Fix for a poll removal request being delayed (Pavel)

   - Rename of a struct member which had a confusing name (Pavel)"

* tag 'io_uring-6.9-20240322' of git://git.kernel.dk/linux:
  io_uring/sqpoll: early exit thread if task_context wasn't allocated
  io_uring: clear opcode specific data for an early failure
  io_uring/net: ensure async prep handlers always initialize ->done_io
  io_uring/waitid: always remove waitid entry for cancel all
  io_uring/futex: always remove futex entry for cancel all
  io_uring: fix poll_remove stalled req completion
  io_uring: Fix release of pinned pages when __io_uaddr_map fails
  io_uring/kbuf: rename is_mapped
  io_uring: simplify io_pages_free
  io_uring: clean rings on NO_MMAP alloc fail
  io_uring/rw: return IOU_ISSUE_SKIP_COMPLETE for multishot retry
  io_uring: don't save/restore iowait state

Merge tag 'for-6.9/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper fixes from Mike Snitzer:

 - Fix a memory leak in DM integrity recheck code that was added during
   the 6.9 merge. Also fix the recheck code to ensure it issues bios
   with proper alignment.

 - Fix DM snapshot's dm_exception_table_exit() to schedule while
   handling an large exception table during snapshot device shutdown.

* tag 'for-6.9/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm-integrity: align the outgoing bio in integrity_recheck
  dm snapshot: fix lockup in dm_exception_table_exit
  dm-integrity: fix a memory leak when rechecking the data

Pull ceph updates from Ilya Dryomov:
 "A patch to minimize blockage when processing very large batches of
  dirty caps and two fixes to better handle EOF in the face of multiple
  clients performing reads and size-extending writes at the same time"

* tag 'ceph-for-6.9-rc1' of https://github.com/ceph/ceph-client:
  ceph: set correct cap mask for getattr request for read
  ceph: stop copying to iter at EOF on sync reads
  ceph: remove SLAB_MEM_SPREAD flag usage
  ceph: break the check delayed cap loop every 5s

Pull xfs fixes from Chandan Babu:

 - Fix invalid pointer dereference by initializing xmbuf before
   tracepoint function is invoked

 - Use memalloc_nofs_save() when inserting into quota radix tree

* tag 'xfs-6.9-merge-9' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: quota radix tree allocations need to be NOFS on insert
  xfs: fix dev_t usage in xmbuf tracepoints

Pull RISC-V updates from Palmer Dabbelt:

 - Support for various vector-accelerated crypto routines

 - Hibernation is now enabled for portable kernel builds

 - mmap_rnd_bits_max is larger on systems with larger VAs

 - Support for fast GUP

 - Support for membarrier-based instruction cache synchronization

 - Support for the Andes hart-level interrupt controller and PMU

 - Some cleanups around unaligned access speed probing and Kconfig
   settings

 - Support for ACPI LPI and CPPC

 - Various cleanus related to barriers

 - A handful of fixes

* tag 'riscv-for-linus-6.9-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (66 commits)
  riscv: Fix syscall wrapper for >word-size arguments
  crypto: riscv - add vector crypto accelerated AES-CBC-CTS
  crypto: riscv - parallelize AES-CBC decryption
  riscv: Only flush the mm icache when setting an exec pte
  riscv: Use kcalloc() instead of kzalloc()
  riscv/barrier: Add missing space after ','
  riscv/barrier: Consolidate fence definitions
  riscv/barrier: Define RISCV_FULL_BARRIER
  riscv/barrier: Define __{mb,rmb,wmb}
  RISC-V: defconfig: Enable CONFIG_ACPI_CPPC_CPUFREQ
  cpufreq: Move CPPC configs to common Kconfig and add RISC-V
  ACPI: RISC-V: Add CPPC driver
  ACPI: Enable ACPI_PROCESSOR for RISC-V
  ACPI: RISC-V: Add LPI driver
  cpuidle: RISC-V: Move few functions to arch/riscv
  riscv: Introduce set_compat_task() in asm/compat.h
  riscv: Introduce is_compat_thread() into compat.h
  riscv: add compile-time test into is_compat_task()
  riscv: Replace direct thread flag check with is_compat_task()
  riscv: Improve arch_get_mmap_end() macro
  ...