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mm: introduce deferred freeing for kernel page tables

commit 5ba2f0a1556479638ac11a3c201421f5515e89f5 upstream.

This introduces a conditional asynchronous mechanism, enabled by
CONFIG_ASYNC_KERNEL_PGTABLE_FREE. When enabled, this mechanism defers the
freeing of pages that are used as page tables for kernel address mappings.
These pages are now queued to a work struct instead of being freed
immediately.

This deferred freeing allows for batch-freeing of page tables, providing a
safe context for performing a single expensive operation (TLB flush) for a
batch of kernel page tables instead of performing that expensive operation
for each page table.

[grogan@nicetry archkern]$ grep -n CONFIG_ASYNC_KERNEL_PGTABLE_FREE .config
1023:CONFIG_ASYNC_KERNEL_PGTABLE_FREE=y

Revert "driver core: enforce device_lock for driver_match_device()"

This reverts commit bc82e5f4d7dc8237ae8cabc73aa46fc93c85d98c which is
commit dc23806a7c47ec5f1293aba407fb69519f976ee0 upstream.

It causes boot regressions on some systems as all of the "fixes" for
drivers are not properly backported yet. Once that is completed, only
then can this be applied, if really necessary given the potential for
explosions, perhaps we might want to wait a few -rc releases first...

netfilter: nf_tables: add .abort_skip_removal flag for set types

commit f175b46d9134f708358b5404730c6dfa200fbf3c upstream.

The pipapo set backend is the only user of the .abort interface so far.
To speed up pipapo abort path, removals are skipped.

The follow up patch updates the rbtree to use to build an array of
ordered elements, then use binary search. This needs a new .abort
interface but, unlike pipapo, it also need to undo/remove elements.

Add a flag and use it from the pipapo set backend.

drm/amdgpu: Refactor amdgpu_gem_va_ioctl for Handling Last Fence Update and Timeline Management v7

[ Upstream commit efdc66fe12b07e7b7d28650bd8d4f7e3bb92c5d4 ]

When GPU memory mappings are updated, the driver returns a fence so
userspace knows when the update is finished.

The previous refactor could pick the wrong fence or rely on checks that
are not safe for GPU mappings that stay valid even when memory is
missing. In some cases this could return an invalid fence or cause fence
reference counting problems.

Fix this by (v5,v6, per Christian):
- Starting from the VM’s existing last update fence, so a valid and
meaningful fence is always returned even when no new work is required.
- Selecting the VM-level fence only for always-valid / PRT mappings using
the required combined bo_va + bo guard.
- Using the per-BO page table update fence for normal MAP and REPLACE
operations.
- For UNMAP and CLEAR, returning the fence provided by
amdgpu_vm_clear_freed(), which may remain unchanged when nothing needs
clearing.
- Keeping fence reference counting balanced.

v7: Drop the extra bo_va/bo NULL guard since
amdgpu_vm_is_bo_always_valid() handles NULL BOs correctly (including
PRT). (Christian)

This makes VM timeline fences correct and prevents crashes caused by
incorrect fence handling.

xfs: fix copy-paste error in previous fix

[ Upstream commit e764dd439d68cfc16724e469db390d779ab49521 ]

Chris Mason noticed that there is a copy-paste error in a recent change
to xrep_dir_teardown that nulls out pointers after freeing the
resources.

Revert "ACPI: processor: Update cpuidle driver check in __acpi_processor_start()"

This reverts commit 0089ce1c056aee547115bdc25c223f8f88c08498 which is
upstream commit 6cfed39c2ce64ac024bbde458a9727105e0b8c66.

This commit is causing a suspend regression on systems such as the Asus
Zephyrus G14 (GA402RJ) with Ryzen 7 6700H: when suspending, the display
turns off but the device fails to fully power down. This is not seen
with v7.0-rc1 which indicates that there are changes missing. Therefore,
revert this change.

drm/amd/display: Correct logic check error for fastboot

[ Upstream commit b6a65009e7ce3f0cc72da18f186adb60717b51a0 ]

[Why]
Fix fastboot broken in driver.
This is caused by an open source backport change 7495962c.

from the comment, the intended check is to disable fastboot
for pre-DCN10. but the logic check is reversed, and causes
fastboot to be disabled on all DCN10 and after.

fastboot is for driver trying to pick up bios used hw setting
and bypass reprogramming the hw if dc_validate_boot_timing()
condition meets.

ata: libata-eh: Fix detection of deferred qc timeouts

[ Upstream commit ee0e6e69a772d601e152e5368a1da25d656122a8 ]

If the ata_qc_for_each_raw() loop finishes without finding a matching SCSI
command for any QC, the variable qc will hold a pointer to the last element
examined, which has the tag i == ATA_MAX_QUEUE - 1. This qc can match the
port deferred QC (ap->deferred_qc).

If that happens, the condition qc == ap->deferred_qc evaluates to true
despite the loop not breaking with a match on the SCSI command for this QC.
In that case, the error handler mistakenly intercepts a command that has
not been issued yet and that has not timed out, and thus erroneously
returning a timeout error.

Fix the problem by checking for i < ATA_MAX_QUEUE in addition to
qc == ap->deferred_qc.

The problem was found by an experimental code review agent based on
gemini-3.1-pro while reviewing backports into v6.18.y.

nvme: fix memory allocation in nvme_pr_read_keys()

[ Upstream commit c3320153769f05fd7fe9d840cb555dd3080ae424 ]

nvme_pr_read_keys() takes num_keys from userspace and uses it to
calculate the allocation size for rse via struct_size(). The upper
limit is PR_KEYS_MAX (64K).

A malicious or buggy userspace can pass a large num_keys value that
results in a 4MB allocation attempt at most, causing a warning in
the page allocator when the order exceeds MAX_PAGE_ORDER.

To fix this, use kvzalloc() instead of kzalloc().

cxl/acpi: Fix CXL_ACPI and CXL_PMEM Kconfig tristate mismatch

commit 93d0fcdddc9e7be9d4f42acbe57bc90dbb0fe75d upstream.

Commit e7e222ad73d9 ("cxl: Move devm_cxl_add_nvdimm_bridge() to
cxl_pmem.ko") moves devm_cxl_add_nvdimm_bridge() into the cxl_pmem file,
which has independent config compile options for built-in or module. The
call from cxl_acpi_probe() is guarded by IS_ENABLED(CONFIG_CXL_PMEM),
which evaluates to true for both =y and =m.

When CONFIG_CXL_PMEM=m, a built-in cxl_acpi attempts to reference a
symbol exported by a module, which fails to link. CXL_PMEM cannot simply
be promoted to =y in this configuration because it depends on LIBNVDIMM,
which may itself be =m.

Add a Kconfig dependency to prevent CXL_ACPI from being built-in when
CXL_PMEM is a module. This contrains CXL_ACPI to =m when CXL_PMEM=m,
while still allowing CXL_ACPI to be freely configured when CXL_PMEM is
either built-in or disabled.