| Age | Commit message (Collapse) | Author | Files | Lines |
|---|
|
show_pte() walks page tables locklessly and can run with interrupts
enabled. A concurrent teardown can free a table page while it is being
walked. It can also clear a parent entry after show_pte() checked it; the
regular pXd_offset() helpers then reread the cleared entry and can derive a
bogus lower-level pointer and fault again.
Use the lockless offset helpers with the saved parent entries, as
gup_fast() does, and pass the saved PMD to pte_offset_map().
For task page tables, arm64 selects MMU_GATHER_RCU_TABLE_FREE. Disable
local interrupts around the walk to hold off RCU-deferred table frees and
block the tlb_remove_table_sync_one() IPI until the walk is finished.
Place the IRQ guard after the header print. This does not make the output a
consistent snapshot, but prevents the task page-table walk from
dereferencing a released table page or deriving a pointer from a different
parent value.
Fixes: 1d18c47c735e ("arm64: MMU fault handling and page table management")
Cc: stable@vger.kernel.org
Assisted-by: LLM
Signed-off-by: Karl Mehltretter <kmehltretter@gmail.com>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
Pull arm64 fixes from Will Deacon:
"A mixture of ptdump, compat and MTE fixes that came in during the
merge window:
- Fix address handling of final memory region in ptdump
- Fix emulation of decrementing load/store multiple from 32-bit task
- Fix SCTLR context-switching for store-only MTE mode
- Fix numerous issues in MTE selftests"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
selftests/arm64: Add MTE test config fragment
selftests/arm64: Fix MTE prctl TAP plan
selftests/arm64: Treat KSM merge_across_nodes as optional
selftests/arm64: Print missing MTE TAP headers
arm64: compat: Fix decrementing LDM/STM alignment emulation
arm64: process: Fix context switching MTE store-only tag check
KVM: arm64: ptdump: Flush the last region
arm64: ptdump: Make note_page_flush() range aware
|
|
Pull dma-mapping updates from Marek Szyprowski:
- swiotlb:
- new configuration option for the default pool size
(Jagadeesh Pagadala)
- reduce overhead for high watermark tracking (chenhuguanshen)
- minor code cleanups and improvements (Vova Sharaienko, Honglei Huang
and Marek Szyprowski)
- add proper tracking of the shared DMA state through direct, pool and
swiotlb paths (Aneesh Kumar K.V)
This is important for confidential-computing
* tag 'dma-mapping-7.3-2026-08-24' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux:
dma/swiotlb: decouple high watermark tracking from CONFIG_DEBUG_FS
MAINTAINERS: update tree for DMA MAPPING HELPERS
dma/swiotlb: introduce Kconfig option for compile-time default pool size
dma-direct: Improve readability of the dma_direct_map_sg() for P2PDMA case
iommu/dma: simplify dma_iova_destroy() and drop the free_iova helper
dma-coherent: use KiB in DMA allocation logs
dma-coherent: fix spacing coding style issue
* tag 'dma-mapping-7.3-2026-08-24-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux: (23 commits)
swiotlb: remove unused SWIOTLB_FORCE flag
dma: swiotlb: handle set_memory_decrypted() failures
dma: swiotlb: free dynamic pools from process context
dma-direct: rename ret to cpu_addr in alloc helpers
dma-direct: select DMA address encoding from __DMA_ATTR_ALLOC_CC_SHARED
dma-direct: set decrypted flag for remapped DMA allocations
dma-direct: make dma_direct_map_phys() honor DMA_ATTR_CC_SHARED
dma-direct: Move dma_direct_map_phys() to dma/direct.c
dma-direct: pass attrs to dma_capable() for DMA_ATTR_CC_SHARED checks
dma-mapping: make dma_pgprot() honor __DMA_ATTR_ALLOC_CC_SHARED
dma: swiotlb: track pool encryption state and honor DMA_ATTR_CC_SHARED
dma: swiotlb: pass mapping attributes by reference
dma-pool: track decrypted atomic pools and select them via attrs
dma-direct: use __DMA_ATTR_ALLOC_CC_SHARED in alloc/free paths
dma-mapping: Add internal shared allocation attribute
coco: arm64: s390: powerpc: Mark secure guests with CC_ATTR_GUEST_MEM_ENCRYPT
dma-direct: swiotlb: handle swiotlb alloc/free outside __dma_direct_alloc_pages
s390: Expose protected virtualization through cc_platform_has()
swiotlb: Preserve allocation virtual address for dynamic pools
dma: free atomic pool pages by physical address
...
|
|
note_page_flush() calls note_page() with addr == 0 and level == -1 to
dump the last row of a ptdump. addr == 0 (1 << 64 wrapped around)
renders a huge region with enormous size for address spaces with
IA bits < 64. For example the stage-2 page tables and the EFI runtime
page table.
More importantly, the last region of the address space and everything
after the address space up to 1 << 64 are merged into one row of
output. If the last region within the address space is valid, it will
appear to remain valid up to 1 << 64 with the same attributes.
Currently only the EFI runtime ptdump is affected by this, but KVM will
soon fix its stage-2 ptdump by using note_page_flush(). Here is an
example of an EFI runtime ptdump (last row):
0x0000008000000000-0x0000000000000000 17179868672G PGD
With this patch:
0x0000008000000000-0x0001000000000000 261632G PGD
To fix this, cache the end address of a ptdump in ptdump_pg_state so
note_page_flush() can call the final note_page() with the correct end
address.
Fixes: 9d80448ac92b ("efi/arm64: Add debugfs node to dump UEFI runtime page tables")
Signed-off-by: Wei-Lin Chang <weilin.chang@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
Pull arm64 updates from Will Deacon:
"There's a reasonable amount of stuff here, including a bunch of
updates to the perf PMU drivers and some MPAM updates to expose the
memory bandwidth counters via resctrl.
On the architecture side, some highlights include support for BBML3
and steps towards support for an architectural NMI solution, all
wrapped up in a web of fixes for latent issues identified by Sashiko.
ACPI:
- Combine reads of AMU counters into a single FFH feedback counter op
Confidential computing:
- Fix smp_processor_id() in preemptible context when retrieving an
attestation token inside a realm
- Convert pKVM over to a "CC platform"
- Clean-up our SWIOTLB configuration in preparation for reworking the
handling of encrypted/decryped DMA buffers in the dma-mapping tree
CPU errata handling:
- Work around broken device memory ordering on NVIDIA Olympus cores
- Fix broken 'nospectre_bhb' command-line option
- Select the idle loop backend instruction on the command-line
CPU features:
- Replace our BBML2-noabort feature with the new architectural BBML3
feature
- Disable in-kernel BTI for recent versions of Clang due to issues
with livepatch that are still being investigated
- Clean-up documentation describing which ID register fields are
exposed to userspace
Interrupts:
- Preliminary work towards supporting FEAT_NMI, which cleans up our
IRQ entry code and fixes some latent issues with pseudo-NMI
- Support for an SDEI backend to trigger an NMI backtrace
Memory management:
- Treat all devices as coherent when CLIDR_EL1.LoC == 0
- Fix no-map handling of sub-page-sized regions
- Second attempt at unmapping the linear aliases of the kernel data
and bss sections
- Fix EFI runtime calls when software-PAN is enabled
Miscellaneous:
- Add Mark Rutland as a reviewer!
- Tidy-up our futex cmpxchg logic when using the new LSUI
instructions
- Drop the requirement on DYNAMIC_FTRACE_WITH_CALL_OPS when
selecting HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
- Fix a false-positive KCSCAN splat in the delay loop
- Use a portable typedef for 128-bit scalar types in our UAPI headers
- Non-critical fixes for Sashiko reports all over
MPAM:
- Hook MPAM memory bandwidth counters into resctrl's counter
assignment interface
- Fix a quirk in the MPAM bandwidth counting on Nvidia T241 so that
it also applies to 63 bit counters
Perf:
- Workarounds for hardware issues in the CMN-S3 PMU (Graviton 5) and
CPU PMU (NVIDIA Olympus again!)
- Add support for the DDR PMU on Marvell CN20K SoCs
- Add support for Picoheart implementations of the DCW PCIe PMU
- Add support for Channel/Rank/Bank filtering in the CXL PMU driver
- Add support for 64-bit counters in the CSPMU device
- Add support for revision 2 of the CMN S3 PMU
Ptrace:
- Fix a decade-old bug in our handling of seccomp and tracing on
syscall entry
- Fix regset handling for inactive SVE and SSVE registers
Selftests
- Add some tests for the decade-old bug that we just tried to fix in
our syscall entry path
- Fix SVE test crash on SME-only CPUs"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (95 commits)
arm64/efi: Avoid voluntary preemption with efi_mm installed
arm64: bti: Disable in-kernel BTI with recent versions of Clang
arm64: entry: Avoid unnecessary local_irq_disable() on kernel exit
irqchip/gic-v3: make the unmasking of pseudo-NMIs explicit when handling IRQs
arm64: Disable KCSAN instrumentation in delay.o
arm_mpam: Disable driver unbind to avoid UAF
arm_mpam: Fix a NULL pointer dereference on unbinding after an error interrupt
perf: arm_pmuv3: Zero initialize hw_id branch stack field
arm64: mm: Unmap kernel data/bss entirely from the linear map
iommu/arm-smmu-v3-sva: Use system_supports_bbml3() to detect CPU feature
perf/arm-cmn: Support CMN S3 r2
perf/arm-cmn: Plumb in new filter types
perf/arm-cmn: Refactor event filter data
perf/arm-cmn: Refactor event filter programming
perf/arm-cmn: Rename filter variables for clarity
arm64: mm: fix accidental linear mapping of no-map reserved memory
tools: Ensure tools copy of linux/filter.h exports the UAPI
kselftest/arm64: Fix abi test compilation errors
arch: arm64: add early_param idle=<wfi|yield|nop>
arm64: entry: mask DAIF before returning from C EL1 handlers
...
|
|
Pull kexec updates from Mike Rapoport:
- Deduplicate crash memory allocation and the exclusion of reserved
crash kernel regions from architecture specific code into a generic
crash_prepare_headers() and enable crashkernel CMA reservation on
arm64 and riscv reservation on arm64 and riscv.
- Skip purgatory checksum verification when the kexec segments cannot
be corrupted by DMA, which saves about 250ms on kexec.
- Replace __ASSEMBLY__ with the compiler provided __ASSEMBLER__ in
include/linux/kexec.h.
- Fix a keyring refcount imbalance in the kdump kernel's dm-crypt key
restore path, which over-dropped the user keyring reference when
more than one key was restored.
* tag 'kexec-v7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/liveupdate/linux:
crash_dump: release keyring reference at the correct time
kexec: Replace __ASSEMBLY__ with __ASSEMBLER__ in header file
kexec_file: skip checksum verification when safe
riscv: kexec_file: Add support for crashkernel CMA reservation
arm64: kexec_file: Add support for crashkernel CMA reservation
powerpc/kexec_file: Use crash_exclude_core_ranges() helper
LoongArch: kexec_file: Use crash_prepare_headers() helper to simplify code
riscv: kexec_file: Use crash_prepare_headers() helper to simplify code
x86/crash: Use crash_prepare_headers() helper to simplify code
arm64: kexec_file: Use crash_prepare_headers() helper to simplify code
crash: Add crash_prepare_headers() to exclude crash kernel memory
powerpc/crash: sort crash memory ranges before preparing elfcorehdr
riscv: kexec_file: Fix crashk_low_res not exclude bug
|
|
Pull memblock updates from Mike Rapoport:
"Non-urgent fixes:
- Fix calculation of node_spanned_pages when running
with 'kernelcore=mirror'
- Properly handle failure to allocate per_cpu_nodestats
in free_area_init_core_hotplug()
- Fix deferred initialization of the memory map for
configurations where node's RAM end is not aligned
on PAGES_PER_SECTION
Cleanups:
- Remove redundant pageblock_align() call in free_unused_memmap()
- Remove unnecessary invalid range checks in users of memblock
iterators. Some users of for_each_mem_range() and
for_each_mem_pfn_range() verify that start < end for each range.
This is redundant because memblock iterators guarantee to never
return an invalid range
- Stop overlapping zones with 'kernelcore=mirror' and align behaviour
of 'kernelcore=mirror' with other variants of kernelcore and
movablecore
- Remove redundant updates of numa_nodes_parsed mask in the callers
of numa_add_memblk(), the latter always updates the mask anyway
- Remove unnecessary initialization of pgdat->per_cpu_nodestats to
NULL, the variable is reset to the actual value a few lines below"
* tag 'memblock-v7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock: (25 commits)
mm/mm_init: deferred_grow_zone(): fix out-of-range first_deferred_pfn
mm/mm_init: remove unnecessary initialization of pgdat->per_cpu_nodestats
mm/mm_init: remove redundant memset in free_area_init()
mm: numa_memblks: use numa_add_reserved_memblk() in numa_cleanup_meminfo()
arch_numa: remove redundant node_possible_map assignment
mm: numa_memblks: remove redundant numa_nodemask_from_meminfo()
LoongArch: remove redundant numa_nodes_parsed node_set()
arch_numa: remove redundant numa_nodes_parsed node_set()
x86/numa: remove redundant numa_nodes_parsed node_set()
of/numa: remove redundant numa_nodes_parsed node_set()
ACPI: NUMA: remove redundant numa_nodes_parsed node_set()
mm: numa_memblks: set numa_nodes_parsed in numa_add_memblk()
mm/mm_init: handle alloc_percpu failure in free_area_init_core_hotplug
mm/mm_init: drop overlap_memmap_init()
mm/mm_init: don't overlap NORMAL and MOVABLE zones with kernelcore=mirror
mm/hugetlb: remove unnecessary empty range check in hugetlb_bootmem_set_nodes()
mm: remove unnecessary empty range check in early_calculate_totalpages()
powerpc64/kasan: Remove unreachable invalid range check in kasan_init_phys_region()
ARM: remove unreachable invalid range check in kasan_init()
riscv: remove unreachable invalid range check in kasan_init()
...
|
|
* for-next/nmi:
arm64: entry: Avoid unnecessary local_irq_disable() on kernel exit
irqchip/gic-v3: make the unmasking of pseudo-NMIs explicit when handling IRQs
arm64: entry: mask DAIF before returning from C EL1 handlers
arm64: suspend: Initialize PMR on resume
arm64: suspend: rely on daif helpers to handle PMR
arm64: hibernate: Restore DAIF state on error
arm64: hibernate: mask DAIF before restoring hibernated kernel
arm64: debug: don't mask DAIF for mdscr_write()
arm64: ptrace: Remove INIT_PSTATE_EL2
|
|
* for-next/mm:
arm64/efi: Avoid voluntary preemption with efi_mm installed
arm64: mm: Unmap kernel data/bss entirely from the linear map
arm64: mm: fix accidental linear mapping of no-map reserved memory
arm64: pgtable: convert pte_present() from macro to static inline
arm64: mm: Treat all devices as dma-coherent when CLIDR_EL1.LoC == 0
|
|
* for-next/cpufeature:
arm64: bti: Disable in-kernel BTI with recent versions of Clang
iommu/arm-smmu-v3-sva: Use system_supports_bbml3() to detect CPU feature
arm64: cpufeature: Detect BBML3 based on ID_AA64MMFR2_EL1.BBM
arm64: cpufeature: Rename BBML2_NOABORT as BBML3
arm64: sysreg: Add BBM_3
arm64: cpufeature: Extend bbml2_noabort support list
arm64: cputype: Add C1-Nano definitions
arm64: cputype: Add Cortex-A520AE definitions
arm64: cpucaps: Remove stale comment about keeping capabilities sorted
arm64: fix cpu-feature-registers Malformed table
arm64: Remove hidden bitfields from cpu-feature-registers.rst
arm64: Sort registers in cpu-feature-registers.rst
arm64: Document missing bitfields in cpu-feature-registers.rst
arm64: Don't number registers in cpu-feature-registers.rst
|
|
The linear aliases of the kernel text and rodata are also mapped
read-only in the linear map. Given that the contents of these regions
are mostly identical to the version in the loadable image, mapping them
read-only and leaving their contents visible is a reasonable hardening
measure.
Data and bss, however, are now also mapped read-only but the contents of
these regions are more likely to contain data that we'd rather not leak.
So let's unmap these entirely in the linear map when the kernel is
running normally.
When going into hibernation or waking up from it, these regions need to
be mapped, so map the region initially, and toggle the valid bit so
map/unmap the region as needed.
Doing so is required because pages covering the kernel image are marked
as PageReserved, and therefore disregarded for snapshotting by the
hibernate logic unless they are mapped.
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Liz Prucka <lizprucka@google.com>
Cc: Seth Jenkins <sethjenkins@google.com>
Cc: Kees Cook <kees@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
When reserved-memory regions with the "no-map" property are not
page-aligned, the kernel may accidentally map them into the linear
mapping, contradicting the no-map semantics.
The root cause is a mismatch between /proc/iomem's address boundaries
and the actual page table mapping boundaries:
1. /proc/iomem derives its ranges from memblock via
memblock_region_reserved_base_pfn/memblock_region_reserved_end_pfn,
which perform PFN rounding so the displayed boundaries are
page-aligned. This gives the impression that the no-map region
occupies whole pages.
2. However, memblock_mark_nomap() splits memblock.memory regions at
exact byte boundaries (memblock_isolate_range preserves raw DT
base/size with no alignment). When for_each_mem_range iterates the
non-NOMAP regions adjacent to a no-map region, it returns start/end
values that are NOT page-aligned — they are the precise byte
boundaries from the memblock split.
3. These sub-page-aligned values are passed to
__create_pgd_mapping_locked(), which does:
phys &= PAGE_MASK;
addr = virt & PAGE_MASK;
end = PAGE_ALIGN(virt + size);
The downward rounding of phys via PAGE_MASK extends the mapped
range backward into the adjacent no-map region, effectively
including no-map memory in the linear mapping.
For example, with 64K pages, reserved_region@A2000000 (base=0xA2000000,
size=0x8000, no-map) causes for_each_mem_range to return
start=0xA2008000 for the next mappable region. After phys &= PAGE_MASK,
the actual mapping starts at 0xA2000000 — the entire no-map region is
incorrectly mapped.
Fix this by rounding the mappable range inward to PAGE_SIZE boundaries
before passing it to __map_memblock: start is rounded UP and end is
rounded DOWN. This ensures the mapped area never overlaps with adjacent
no-map regions. The cost is at most one page of unmapped gap at each
boundary, which is preferable to violating no-map semantics.
Signed-off-by: liulhong617 <liulhong617@gmail.com>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
When we resume from cpu_suspend() context tracking, specially,
ct_idle_exit() performs IRQ save/restore sequence. It doesn't cause
any functional issues since we have masked all exceptions prior
suspend and have not restored them. However, in case of pseudo-NMI PMR
can be set by firmware to arbitrary value, thus IRQ save/restore
routines manipulates this arbitrary value. Again, it doesn't cause any
issues since PMR variant of IRQ save helper carries a
__pmr_irqs_disabled_flags() guard.
Going forward __pmr_irqs_disabled_flags() guard will be gone and we
will call __pmr_local_irq_disable() unconditionally - that would cause
warning in case CONFIG_ARM64_DEBUG_PRIORITY_MASKING is set.
Initialize PMR to a value known to Linux on resume until the normal
exception restore path restores the saved DAIF and PMR state.
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
- As bbml2_noabort is functionally equivalent to bbml3,
rename cpu/system_supports_bbml2_noabort to
cpu/system_supports_bbml3.
The ARM64 capability name is also renamed accordingly.
- As BBML2_NOABORT or the equivalent BBML3 is the
kernel requirement for setting up linear map with
block/contpte mappings and not BBML2, replace all
bbml2 references with bbml3.
FEAT_BBML3, is introduced as part of 2025 Architecture Extensions.
https://developer.arm.com/documentation/109697/2026_03/2025-Architecture-Extensions
No functional changes are introduced with this patch.
Reviewed-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Linu Cherian <linu.cherian@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
This partially reverts commit fa93b45fd397 ("arm64: Enable vmalloc-huge
with ptdump"), retaining vmalloc-huge support but eliminating the now
redundant mitigation against a race between huge vmap page table freeing
and ptdump, as this issue has now been fixed at core.
We also simultaneously remove the arm64 if-deffery when acquiring the mmap
read lock upon vmap huge page table promotion as it is no longer required.
Note that this patch relies on the preceding vmalloc patch, and should not
be backported alone.
Link: https://lore.kernel.org/20260723-series-vmap-race-fix-v6-5-8cc77dcc0018@kernel.org
Fixes: fa93b45fd397 ("arm64: Enable vmalloc-huge with ptdump")
Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
Reviewed-by: Dev Jain <dev.jain@arm.com>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Acked-by: Kiryl Shutsemau (Meta) <kas@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Reviewed-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: "Borah, Chaitanya Kumar" <chaitanya.kumar.borah@intel.com>
Cc: "Borislav Petkov (AMD)" <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Carlier <devnexen@gmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
On systems where CLIDR_EL1.LoC == 0, no cache maintenance is required
when cleaning or invalidating to the Point of Coherency and therefore
all DMA agents can be treated as coherent.
Extend arch_setup_dma_ops() to take CLIDR_EL1.LoC into account when
setting the DMA ops for a device, emitting a warning message if the
firmware advertises a non-coherent device on a fully coherent system.
Cc: Steffen Eiden <seiden@linux.ibm.com>
Cc: Andreas Grapentin <gra@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
Teach dma_direct_map_phys() to select the DMA address encoding based on
DMA_ATTR_CC_SHARED.
Use phys_to_dma_unencrypted() for decrypted mappings and
phys_to_dma_encrypted() otherwise. If a device requires unencrypted DMA
but the source physical address is still encrypted, force the mapping
through swiotlb so the DMA address and backing memory attributes remain
consistent.
Update the arm64, x86, s390 and powerpc secure-guest setup to not use
swiotlb force option
Tested-by: Jiri Pirko <jiri@nvidia.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Mostafa Saleh <smostafa@google.com>
Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org>
Link: https://lore.kernel.org/r/20260717180442.110954-18-aneesh.kumar@kernel.org
[mszyprow: rebased onto latest changes in arch/arm64/mm/init.c]
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
|
|
arm64 Realms, powerpc secure guests and s390 protected virtualization
guests currently report CC_ATTR_MEM_ENCRYPT, but not
CC_ATTR_GUEST_MEM_ENCRYPT.
These environments are all secure guest configurations. Their
force_dma_unencrypted() implementations also treat the same secure guest
state as requiring unencrypted DMA. Report CC_ATTR_GUEST_MEM_ENCRYPT for
the same condition so generic confidential-computing code can distinguish
guest memory encryption from host memory encryption instead of relying only
on CC_ATTR_MEM_ENCRYPT.
Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org>
Link: https://lore.kernel.org/r/20260717180442.110954-9-aneesh.kumar@kernel.org
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
|
|
huge_ptep_get() can be handed a virtual address pointing to the middle
of a contpmd/contpte mapped hugetlb folio (examples of callers are
pagemap_hugetlb_range, page_mapped_in_vma).
The arm64 helper rewalks the pgtables in find_num_contig to answer
whether the huge pte we have maps a contpmd or a contpte hugetlb folio,
and returns CONT_PMDS or CONT_PTES, so that it can collect a/d bits over
the contiguous ptes. We can falsely return CONT_PTES instead of
CONT_PMDS if the addr is not aligned. On systems where CONT_PTES !=
CONT_PMDS (meaning page size is 16K), we could collect excess A/D bit
state, meaning extra work for the kernel. Even worse, we may iterate
beyond the PTE table and dereference a garbage ptep pointer to access
physical memory we don't own. Since the ptep pointer is a linear map
address, we may run off the end of the linear map or into a hole,
dereference a VA not mapped into the kernel pgtables and cause kernel
panic.
Fix this by aligning the pmdp pointer down to a contpmd base before
checking equality with the passed huge pte pointer, to correctly answer
whether the huge pte is the base of a contpmd block.
Fixes: 29cb80519689 ("arm64: hugetlb: Cleanup huge_pte size discovery mechanisms")
Cc: stable@vger.kernel.org
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Signed-off-by: Dev Jain <dev.jain@arm.com>
Acked-by: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
pKVM does support memory encryption, expose that to the rest of
the kernel through cc_platform_has()
At the moment, all devices inside the guest are emulated which
requires its memory to be shared back to the host (decrypted), so
set force_dma_unencrypted() to always return true.
Although, typically pKVM guests rely on restricted-dma-pools to
bounce traffic, with this change, it is possible to solely rely on
the default SWIOTLB for that (assuming the appropriate size is set
from the command line)
Signed-off-by: Mostafa Saleh <smostafa@google.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
At the moment, arch_mm_preinit() checks if the system has limited
addressing or is running under CCA to enable SWIOTLB, only after to
be forced to true anyway if it was false due to
CONFIG_DMA_BOUNCE_UNALIGNED_KMALLOC being unconditionally true for
arm64.
Simplify this logic, by making it clear that SWIOTLB is always used
but its size depends on the address layout of the system.
Signed-off-by: Mostafa Saleh <smostafa@google.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org>
Tested-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
prevent_memory_remove_notifier() advances pfn while scanning the requested
range for early memory. When the loop completes, pfn is at or beyond
end_pfn. Passing it to can_unmap_without_split() therefore checks a range
after the one being offlined.
Consequently, a valid request can be rejected based on the following
range, while a request that would split a leaf mapping can be accepted if
the shifted range can be unmapped without a split. This was observed with
CXL DAX memory, where the final memory block was incorrectly allowed to
be offlined.
Pass arg->start_pfn into can_unmap_without_split() so it checks the
requested range.
Fixes: 95a58852b0e5 ("arm64/mm: Reject memory removal that splits a kernel leaf mapping")
Signed-off-by: Richard Cheng <icheng@nvidia.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
When logging the decode of a data abort we currently unconditionally decode
and display Xs. Currently the only defined non-RES0 values for this field
are for cases where ISV=1, move the decode of Xs into our existing check
for ISV=1. This avoids potential confusion if some other use is assigned to
these bits for ISV=0 cases in future, or misleading someone into thinking
there is a meaningful value there with currently defined architecture.
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
kasan_init_shadow() maps each memblock region with for_each_mem_range()
and breaks the loop when start >= end. for_each_mem_range() never returns
an invalid range, so start < end always.
Therefore the start >= end check is unreachable, so remove it.
No functional change.
Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com>
Reviewed-by: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Link: https://patch.msgid.link/20260630150413.1718632-2-ekffu200098@gmail.com
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
|
|
Commit 35c18f2933c5 ("Add a new optional ",cma" suffix to the
crashkernel= command line option") and commit ab475510e042 ("kdump:
implement reserve_crashkernel_cma") added CMA support for kdump
crashkernel reservation.
Crash kernel memory reservation wastes production resources if too
large, risks kdump failure if too small, and faces allocation difficulties
on fragmented systems due to contiguous block constraints. The new
CMA-based crashkernel reservation scheme splits the "large fixed
reservation" into a "small fixed region + large CMA dynamic region": the
CMA memory is available to userspace during normal operation to avoid
waste, and is reclaimed for kdump upon crash—saving memory while
improving reliability.
So extend crashkernel CMA reservation support to arm64. The following
changes are made to enable CMA reservation:
- Parse and obtain the CMA reservation size along with other crashkernel
parameters.
- Call reserve_crashkernel_cma() to allocate the CMA region for kdump.
- Include the CMA-reserved ranges for kdump kernel to use.
- Exclude the CMA-reserved ranges from the crash kernel memory to
prevent them from being exported through /proc/vmcore, which is already
done in the crash core.
Update kernel-parameters.txt to document CMA support for crashkernel on
arm64 architecture.
Tested-by: Breno Leitao <leitao@debian.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Acked-by: Baoquan He <bhe@redhat.com>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Link: https://patch.msgid.link/20260629094746.191843-10-ruanjinjie@huawei.com
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
|
|
Commit 48478b9f7913 ("arm64/mm: Enable batched TLB flush in
unmap_hotplug_range") inadvertently introduced redundant TLB
invalidation when clearing a block entry, resulting in unnecessary
broadcast invalidation on CPUs without support for range-based
invalidation.
Re-introduce the old behaviour, along with some expanded comments to
help people working in this area next time around.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Reported-by: Ben Hutchings <ben@decadent.org.uk>
Closes: https://lore.kernel.org/all/b0d5836032ce3135bfc473f6bff791306d086925.camel@decadent.org.uk/
Fixes: 48478b9f7913 ("arm64/mm: Enable batched TLB flush in unmap_hotplug_range()")
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
[will: Reword comments and commit message]
Signed-off-by: Will Deacon <will@kernel.org>
|
|
Pull arm64 fixes from Will Deacon:
"Small crop of arm64 fixes for -rc1. We've got a build fix for a new
randconfig permutation, a fix for a long-standing truncation issue
with hardware watchpoints and a KVM initialisation fix for the newly
merged remapping of the kernel data and bss sections:
- Fix randconfig build failure due to missing include of asm/insn.h
- Reject unaligned hardware watchpoints which were silently being
truncated
- Fix crash in KVM initialisation by deferring the read-only
remapping of the kernel data and bss sections"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: mm: Defer read-only remap of data/bss linear alias
arm64/hw_breakpoint: reject unaligned watchpoints that would truncate BAS
arm64: static_call: include asm/insns.h
|
|
Since commit
f2ba877402e5 ("arm64: mm: Map the kernel data/bss read-only in the linear map")
the linear alias of the .data and .bss regions is remapped read-only
early during the boot. (Note that a subsequent patch to unmap this
region entirely was reverted just before the v7.2 merge window, and will
be brought back in an improved form for the v7.3 cycle)
Fuad reports that in some cases, the KVM init code may apply relocations
to variables that reside in .data, and does so via the linear map. This
means that remapping .data read-only beforehand is a bad idea, and
results in an early boot crash.
These variables in .data are only present when CONFIG_NVHE_EL2_DEBUG or
CONFIG_NVHE_EL2_TRACING are enabled, which is why it was not spotted in
testing.
So move the remap to mark_rodata_ro(), which is a reasonable place to
put this, and ensures that it happens much later during the boot. It
also means that rodata=off is now taken into account, and so the linear
alias will remain writable in that case.
Fixes: f2ba877402e5 ("arm64: mm: Map the kernel data/bss read-only in the linear map")
Reviewed-by: Fuad Tabba <fuad.tabba@linux.dev>
Tested-by: Fuad Tabba <fuad.tabba@linux.dev>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Kevin Brodsky <kevin.brodsky@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
Pull MM updates from Andrew Morton:
- "selftests/mm: clean up build output and verbosity" (Li Wang)
Remove some noise from the MM selftests build
- "mm: Free contiguous order-0 pages efficiently" (Ryan Roberts)
Speed up the freeing of a batch of 0-order pages by first scanning
them for coalescing opportunities. This is applicable to vfree() and
to the releasing of frozen pages
- "mm/damon: introduce DAMOS failed region quota charge ratio"
(SeongJae Park)
Address a DAMOS usability issue: The DAMOS quota often exhausts
prematurely because it charges for all memory attempted, causing slow
and inconsistent performance when actions fail on unreclaimable
memory.
To fix this, a new feature lets users set a smaller, flexible quota
charge ratio (via a numerator and denominator) for failed regions.
Since failed actions cause less overhead, reducing their quota cost
ensures more predictable and efficient DAMOS processing
- "selftests/cgroup: improve zswap tests robustness and support large
page sizes" (Li Wang)
Fix various spurious failures and improves the overall robustness of
the cgroup zswap selftests
- "fix MAP_DROPPABLE not supported errno" (Anthony Yznaga)
Fix an issue in the mlock selftests on arm32
- "mm: huge_memory: clean up defrag sysfs with shared" (Breno Leitao)
Some maintenance work in the huge_memory code
- "treewide: fixup gfp_t printks" (Brendan Jackman)
Use the special vprintf() gfp_t conversion in various places
- "mm: Fix vmemmap optimization accounting and initialization" (Muchun
Song)
Fix several bugs in the vmemmap optimization, mainly around incorrect
page accounting and memmap initialization in the DAX and memory
hotplug paths. It also fixes pageblock migratetype initialization and
struct page initialization for ZONE_DEVICE compound pages
- "mm/damon: repost non-hotfix reviewed patches in damon/next tree"
A sprinkle of unrelated minor bugfixes for DAMON
- "mm: remove page_mapped()" (David Hildenbrand)
Remove this function from the tree, replacing it with folio_mapped()
- "mm/damon: let DAMON be paused and resumed" (SeongJae Park)
Allow DAMON to be paused and resumed without losing its current state
- "kasan: hw_tags: Disable tagging for stack and page-tables" (Muhammad
Usama Anjum)
Simplify and speed up kasan by removing its ineffective tagging of
stacks and page tables
- "mm/damon/reclaim,lru_sort: monitor all system rams by default"
(SeongJae Park)
Simplify deployment on diverse hardware like NUMA systems by updating
DAMON_RECLAIM and DAMON_LRU_SORT to automatically monitor the
physical address range covering all System RAM areas by default,
replacing the overly restrictive behavior that only targeted the
single largest memory block to save on negligible overhead
- "mm/damon/sysfs: document filters/ directory as deprecated" (SeongJae
Park)
Update some DAMON docs
- "mm: use spinlock guards for zone lock" (Dmitry Ilvokhin)
Switch zone->lock handling over to using the guard() mechanisms
- "mm/filemap: tighten mmap_miss hit accounting" (fujunjie)
Fix a flaw where the mmap_miss counter over-credited page cache hits
during fault-arounds and page-fault retries. This results in
significant reduction of redundant synchronous mmap readahead I/O,
drastically cutting down execution time and gigabytes read for sparse
random or strided memory access workloads
- "selftests/cgroup: Fix false positive failures in test_percpu_basic"
(Li Wang)
Fix a couple of false-positives in the cgroup kmem selftests
- "mm/damon/reclaim: support monitoring intervals auto-tuning"
(SeongJae Park)
Add a new parameter to DAMON permitting DAMON_RECLAIM to
automatically tune DAMON's sampling and aggregation intervals
- "mm/damon/stat: add kdamond_pid parameter" (SeongJae Park)
Change DAMON_STAT to provide the pid of its kdamond
- "mm/kmemleak: dedupe verbose scan output" (Breno Leitao)
Remove large amounts of duplicated backtraces from the verbose-mode
kmemleak output
- "mm: remove CONFIG_HAVE_BOOTMEM_INFO_NODE (Part 1)" (David
Hildenbrand)
Reduce our use of CONFIG_HAVE_BOOTMEM_INFO_NODE, with a view to
removing it entirely in a later series
- "mm/damon: validate min_region_size to be power of 2" (Liew Rui Yan)
Prevent users from passing a non-power-of-2 value of `addr_unit', as
this later results in undesirable behavior
- "mm: document read_pages and simplify usage" (Frederick Mayle)
- "tools/mm/page-types: Fix misc bugs" (Ye Liu)
Fix three issues in tools/mm/page-types.c
- "mm: misc cleanups from __GFP_UNMAPPED series" (Brendan Jackman)
Implement several cleanups in the page allocator and related code
- "mm, swap: swap table phase IV: unify allocation" (Kairui Song)
Unify the allocation and charging of anon and shmem swap in folios,
provides better synchronization, consolidates the metadata
management, hence dropping the static array and map, and improves
performance
- "mm/damon: introduce data attributes monitoring" (SeongJae Park(
Extend DAMON to monitor general data attributes other than accesses
- "mm/vmalloc: free unused pages on vrealloc() shrink" (Shivam Kalra)
Implement the TODO in vrealloc() to unmap and free unused pages when
shrinking across a page boundary
- "mm/damon: documentation and comment fixes" (niecheng)
- "remove mmap_action success, error hooks" (Lorenzo Stoakes)
Eliminate custom hooks from mmap_action by removing the problematic
success_hook which allowed drivers to improperly access uninitialized
VMAs. It replaces the error_hook with a simple error-code field and
updates the memory char driver accordingly
- "mm/damon: minor improvements for code readability and tests"
(SeongJae Park)
- "mm/damon: fix macro arguments and clarify quota goals doc" (Maksym
Shcherba)
- "userfaultfd: merge fs/userfaultfd.c into mm/userfaultfd.c" (Mike
Rapoport)
- "mm/mglru: improve reclaim loop and dirty folio" (Kairui Song and
others)
Clean up and slightly improves MGLRU's reclaim loop and dirty
writeback handling. Large performance improvements are measured
- "use vma locks for proc/pid/{smaps|numa_maps} reads" (Suren
Baghdasaryan)
Use per-vma locks when reading /proc/pid/smaps and numa_maps similar
to reduce contention on central mmap_lock
- "refactors thpsize_shmem_enabled_store() and thpsize_shmem_enabled_show()"
(Ran Xiaokai)
Some cleanup work in the THP code
- "selftests/memfd: fix compilation warnings" (Konstantin Khorenko)
Fix a few build glitches in the memfd selftest code.
- "memcg: shrink obj_stock_pcp and cache multiple objcgs" (Shakeel
Butt)
Resolve a 68% performance regression caused by NUMA-node cache
thrashing around struct obj_stock_pcp by shrinking its existing
fields and expanding it into a multi-slot array that caches up to
five obj_cgroup pointers per CPU, allowing per-node variants of the
same memcg to coexist within a single 64-byte cache line.
- "zram: writeback fixes" (Sergey Senozhatsky)
address a couple of unrelated zram writeback issues
- "mm: switch THP shrinker to list_lru" (Johannes Weiner)
Resolve NUMA-awareness issues and streamlines callsite interaction by
refactoring and extending the list_lru API to completely replace the
complex, open-coded deferred split queue for Transparent Huge Pages
- "mm: improve large folio readahead for exec memory" (Usama Arif)
Improve large-folio readahead on systems like 64K-page arm64 by
preventing the mmap_miss check from permanently disabling
target-oriented VM_EXEC readahead, and by generalizing the
force_thp_readahead gate to support mappings with any usefully large
maximum folio order under the cache cap.
- "userfaultfd/pagemap: pre-existing fixes" (Kiryl Shutsemau)
Fix a bunch of minor issues in the userfaultfd/pagemap, all of which
were flagged by Sashiko review of proposed new material
- "mm/sparse-vmemmap: Provide generic vmemmap_set_pmd() and
vmemmap_check_pmd()" (Muchun Song)
Provide generic versions of these two functions so the four
arch-specific implementations can be removed.
- "mm/swap, PM: hibernate: fix swapoff race in uswsusp by pinning swap
device" (Youngjun Park)
Address a uswsusp-vs-swapoff race and reduces the swap device
reference taking/releasing frequency.
- "mm/hmm: A fix and a selftest" (Dev Jain)
* tag 'mm-stable-2026-06-18-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits)
selftests/mm/hmm-tests: test pagemap reads of PMD device-private entries
fs/proc/task_mmu: do not warn on seeing non-migration pmd entry
lib/test_hmm: check alloc_page_vma() return value and handle OOM
mm/compaction: cap compact_gap() at COMPACT_CLUSTER_MAX
mm/swap: remove redundant swap device reference in alloc/free
mm/swap, PM: hibernate: fix swapoff race in uswsusp by pinning swap device
mm/filemap: use folio_next_index() for start
vmalloc: fix NULL pointer dereference in is_vm_area_hugepages()
sparc/mm: drop vmemmap_check_pmd helper and use generic code
loongarch/mm: drop vmemmap_check_pmd helper and use generic code
riscv/mm: drop vmemmap_pmd helpers and use generic code
arm64/mm: drop vmemmap_pmd helpers and use generic code
mm/sparse-vmemmap: provide generic vmemmap_set_pmd() and vmemmap_check_pmd()
rust: page: mark Page::nid as inline
userfaultfd: build __VMA_UFFD_FLAGS from config-gated masks
userfaultfd: gate must_wait writability check on pte_present()
mm/huge_memory: preserve pmd_swp_uffd_wp on device-private PMD downgrade
fs/proc/task_mmu: fix hugetlb self-deadlock in pagemap_scan_pte_hole()
fs/proc/task_mmu: use huge_page_size() in pagemap_scan_hugetlb_entry()
fs/proc/task_mmu: fix make_uffd_wp_huge_pte() prot-update race
...
|
|
Pull bpf updates from Alexei Starovoitov:
"Major changes:
- Recover from BPF arena page faults using a scratch page and add
ptep_try_set() for lockless empty-slot installs on x86 and arm64.
This allows BPF kfuncs to access arena pointers directly.
The 'arena_direct_access' stable branch was created for this work
and was pulled into sched-ext and bpf-next trees (Tejun Heo, Kumar
Kartikeya Dwivedi)
- Lift old restriction and support 6+ arguments in BPF programs and
kfuncs on x86 and arm64 (Yonghong Song, Puranjay Mohan)
Other features and fixes:
- Add 24-bit BTF vlen and reclaim unused bits in the BTF UAPI to ease
addition of new BTF kinds (Alan Maguire)
- Raise the maximum BPF call chain depth from 8 to 16 frames (Alexei
Starovoitov)
- Refactor object relationship tracking in the verifier and fix a
dynptr use-after-free bug (Amery Hung)
- Harden the signed program loader and reject exclusive maps as inner
maps (Daniel Borkmann)
- Replace the verifier min/max bounds fields with a circular number
(cnum) representation and improve 32->64 bit range refinements
(Eduard Zingerman)
- Introduce the arena library and runtime (libarena) with a buddy
allocator, rbtree and SPMC queue data structures, ASAN support and
a parallel test harness. Allow subprograms to return arena pointers
and switch to a BTF type-tag based __arena annotation (Emil
Tsalapatis)
- Cache build IDs in the sleepable stackmap path and avoid faultable
build ID reads under mm locks (Ihor Solodrai)
- Introduce the tracing_multi link to attach a single BPF program to
many kernel functions at once. Allow specifying the uprobe_multi
target via FD (Jiri Olsa)
- Extend the bpf_list family of kfuncs with bpf_list_add/del(), and
bpf_list_is_first/is_last/empty() (Kaitao Cheng)
- Extend the BPF syscall with common attributes support for
prog_load, btf_load and map_create (Leon Hwang)
- Wrap rhashtable as BPF map (Mykyta Yatsenko, Herbert Xu)
- Add sleepable support for tracepoint programs and fix deadlocks in
LRU map due to NMI reentry (Mykyta Yatsenko)
- Fix OOB access in bpf_flow_keys, fix nullness analysis of inner
arrays, enforce write checks for global subprograms (Nuoqi Gui)
- Report the maximum combined stack depth and print a breakdown of
instructions processed per subprogram (Paul Chaignon)
- Add an XDP load-balancer benchmark and arm64 JIT support for stack
arguments (Puranjay Mohan)
- Add kfuncs to traverse over wakeup_sources (Samuel Wu)
- Allow sleepable BPF programs to use LPM trie maps directly (Vlad
Poenaru)
- Many more fixes and cleanups across the verifier, BTF, sockmap,
devmap, bpffs, security hooks, s390/riscv/loongarch JITs,
rqspinlock, libbpf, bpftool, selftests"
* tag 'bpf-next-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (336 commits)
selftests/bpf: Work around llvm stack overflow in crypto progs
selftests/bpf: add test for bpf_msg_pop_data() overflow
bpf, sockmap: fix integer overflow in bpf_msg_pop_data() bounds check
sockmap: Fix use-after-free in udp_bpf_recvmsg()
bpf, sockmap: keep sk_msg copy state in sync
bpf, sockmap: Fix wrong rsge offset in bpf_msg_push_data()
bpf, sockmap: reject overflowing copy + len in bpf_msg_push_data()
selftsets/bpf: Retry map update on helper_fill_hashmap()
selftests/bpf: Add test for sleepable lsm_cgroup rejection
selftests/bpf: Add test to verify the fix for bpf_setsockopt() helper
bpf: Fix bpf_get/setsockopt to tos for ipv4-mapped ipv6 socket
selftests/bpf: Avoid static LLVM linking for cross builds
selftests/bpf: Use common CFLAGS for urandom_read
selftests/bpf: Initialize operation name before use
tools/bpf: build: Append extra cflags
libbpf: Initialize CFLAGS before including Makefile.include
bpftool: Append extra host flags
bpftool: Avoid adding EXTRA_CFLAGS to HOST_CFLAGS
bpftool: Pass host flags to bootstrap libbpf
selftests/bpf: correct CONFIG_PPC64 macro name in comment
...
|
|
Pull arm64 updates from Will Deacon:
"It feels like the new world of AI tooling has slowed us down a little
on the feature side when compared to the fixes side. The extra rounds
of Sashiko review have also pushed a few things out until next time.
Still, there's some good foundational stuff here for the fpsimd code
and hardening work towards removing the predictable linear alias of
the kernel image.
CPU errata handling:
- Extend CnP disabling workaround to HiSilicon HIP09 hardware.
- Work around eternally broken broadcast TLB invalidation on more
CPUs.
- Documentation and code cleanups.
CPU features:
- Add new hwcaps for the 2025 dpISA extensions.
Floating point / SVE / SME:
- Significant cleanup to the low-level state management code in the
core architecture code and KVM.
- Use correct register widths during SVE/SME save/restore assembly.
- Expose SVE/SME save/restore memory accesses to sanitisers.
Memory management:
- Preparatory work for unmapping the kernel data and bss sections
from the linear map.
Miscellaneous:
- Inline DAIF manipulation helpers so they can be used safely from
non-instrumentable code.
- Fix handling of the 'nosmp' cmdline option to avoid marking
secondary cores as "possible".
MPAM:
- Add support for v0.1 of the MPAM architecture.
Perf:
- Update HiSilicon PMU MAINTAINERS entry.
- Fix event encodings for the DVM node in the CMN driver.
Selftests:
- Extend sigframe tests to cover POE context.
- Add coverage for the newly added 2025 dpISA hwcaps.
System registers:
- Add new registers and ESR encodings for the HDBSS feature.
Plus minor fixes and cleanups across the board"
* tag 'arm64-upstream' of gitolite.kernel.org:pub/scm/linux/kernel/git/arm64/linux: (73 commits)
arm64: errata: Mitigate TLBI errata on Microsoft Azure Cobalt 100 CPU
arm64: errata: Mitigate TLBI errata on NVIDIA Olympus CPU
arm64: errata: Mitigate TLBI errata on various Arm CPUs
arm64: cputype: Add C1-Premium definitions
arm64: cputype: Add C1-Ultra definitions
Revert "arm64: mm: Unmap kernel data/bss entirely from the linear map"
Revert "arm64: mm: Defer remap of linear alias of data/bss"
arm64: arch_timer: reuse arch_timer_read_cnt{p,v}ct_el0() helpers
arm64/mm: Rename ptdesc_t
arm64: mm: Defer remap of linear alias of data/bss
KVM: arm64: Omit tag sync on stage-2 mappings of the zero page
arm64: Avoid double evaluation of __ptep_get()
kasan: Move generic KASAN page tables out of BSS too
arm64: Rename page table BSS section to .bss..pgtbl
arm64: patching: replace min_t with min in __text_poke
perf/arm-cmn: Fix DVM node events
arm64: fpsimd: Remove <asm/fpsimdmacros.h>
arm64: fpsimd: Move SME save/restore inline
arm64: fpsimd: Move sve_flush_live() inline
arm64: fpsimd: Move SVE save/restore inline
...
|
|
Pull driver core updates from Danilo Krummrich:
"Deferred probe:
- Fix race where deferred probe timeout work could be permanently
canceled by using mod_delayed_work()
- Fix missing jiffies conversion in deferred_probe_extend_timeout()
- Guard timeout extension with delayed_work_pending() to prevent
premature firing
- Use system_percpu_wq instead of the deprecated system_wq
- Update deferred_probe_timeout documentation
device:
- Replace direct struct device bitfield access (can_match, dma_iommu,
dma_skip_sync, dma_ops_bypass, state_synced, dma_coherent,
of_node_reused, offline, offline_disabled) with flag-based
accessors using bit operations
- Reject devices with unregistered buses
- Delete unused DEVICE_ATTR_PREALLOC()
- Add low-level device attribute macros with const show/store
callbacks, allowing device attributes to reside in read-only memory
- Move core device attributes to read-only memory
- Constify group array pointers in driver_add_groups() /
driver_remove_groups(), struct bus_type, and struct device_driver
device property:
- Fix fwnode reference leak in fwnode_graph_get_endpoint_by_id()
- Initialize all fields of fwnode_handle in fwnode_init()
- Provide swnode_get()/swnode_put() wrappers around kobject_get/put()
- Allow passing struct software_node_ref_args pointers directly to
PROPERTY_ENTRY_REF()
driver_override:
- Migrate amba, cdx, vmbus, and rpmsg to the generic driver_override
infrastructure, fixing a UAF from unsynchronized access to
driver_override in bus match() callbacks
- Remove the now-unused driver_set_override()
firmware loader:
- Fix recursive lock deadlock in device_cache_fw_images() when async
work falls back to synchronous execution
- Fix device reference leak in firmware_upload_register()
platform:
- Pass KBUILD_MODNAME through the platform driver registration macro
to create module symlinks in sysfs for built-in drivers; move
module_kset initialization to a pure_initcall and tegra cbb
registration to core_initcall to ensure correct ordering
- Pass THIS_MODULE implicitly through a coresight_init_driver() macro
sysfs:
- Upgrade OOB write detection in sysfs_kf_seq_show() from printk to
WARN
- Add return value clamping to sysfs_kf_read()
Rust:
- ACPI:
Fix missing match data for PRP0001 by exporting
acpi_of_match_device()
- Auxiliary:
Replace drvdata() with dedicated registration data on
auxiliary_device. drvdata() exposed the driver's bus device private
data beyond the driver's own scope, creating ordering constraints
and forcing the data to outlive all registrations that access it.
Registration data is instead scoped structurally to the
Registration object, making lifecycle ordering enforced by
construction rather than convention.
- Rust-native device driver lifetimes (HRT):
Allow Rust device drivers to carry a lifetime parameter on their
bus device private data, tied to the device binding scope -- the
interval during which a bus device is bound to a driver. Device
resources like pci::Bar<'a> and IoMem<'a> can be stored directly in
the driver's bus device private data with a lifetime bounded by the
binding scope, so the compiler enforces at build time that they do
not outlive the binding. This removes Devres indirection from every
access site and eliminates try_access() failure paths in
destructors.
Bus driver traits use a Generic Associated Type (GAT) Data<'bound>
to introduce the lifetime on the private data, rather than
parameterizing the Driver trait itself. Auxiliary registration
data, where the lifetime is not introduced by a trait callback but
must be threaded through Registration, uses the ForLt trait (a
type-level abstraction for types generic over a lifetime).
Misc:
- Fix DT overlayed devices not probing by reverting the broken
treewide overlay fix and re-running fw_devlink consumer pickup when
an overlay is applied to a bound device
- Use root_device_register() for faux bus root device; add sanity
check for failed bus init
- Fix dev_has_sync_state() data race with READ_ONCE() and move it to
base.h
- Avoid spurious device_links warning when removing a device while
its supplier is unbinding
- Switch ISA bus to dynamic root device
- Fix suspicious RCU usage in kernfs_put()
- Remove devcoredump exit callback
- Constify devfreq_event_class"
* tag 'driver-core-7.2-rc1' of gitolite.kernel.org:pub/scm/linux/kernel/git/driver-core/driver-core: (81 commits)
software node: allow passing reference args to PROPERTY_ENTRY_REF()
driver core: platform: set mod_name in driver registration
coresight: pass THIS_MODULE implicitly through a macro
kernel: param: initialize module_kset in a pure_initcall
soc/tegra: cbb: Move driver registration from pure_initcall to core_initcall
firmware_loader: Fix recursive lock in device_cache_fw_images()
driver core: Use system_percpu_wq instead of system_wq
driver core: remove driver_set_override()
rpmsg: use generic driver_override infrastructure
Drivers: hv: vmbus: use generic driver_override infrastructure
cdx: use generic driver_override infrastructure
amba: use generic driver_override infrastructure
rust: devres: add 'static bound to Devres<T>
samples: rust: rust_driver_auxiliary: showcase lifetime-bound registration data
rust: auxiliary: generalize Registration over ForLt
rust: types: add `ForLt` trait for higher-ranked lifetime support
gpu: nova-core: separate driver type from driver data
samples: rust: rust_driver_pci: use HRT lifetime for Bar
rust: io: make IoMem and ExclusiveIoMem lifetime-parameterized
rust: pci: make Bar lifetime-parameterized
...
|
|
This reverts commit 63e0b6a5b6934d6a919d1c65ea185303200a1874.
Unmapping the kernel '.bss' appears to break KVM initialisation on some
devices, breaking the boot on popular platforms such as RaspberryPi3 and
4.
Revert this change for now so that we can revisit it in future.
Reported-by: Mark Brown <broonie@kernel.org>
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/all/aicVyebkEMs6w6UV@sirena.co.uk
Link: https://lore.kernel.org/r/a1b27e97-182c-485d-a448-56c19c5de2c2@samsung.com
Signed-off-by: Will Deacon <will@kernel.org>
|
|
This reverts commit 53205d56212cbff880a77497e25a0e44036d490a.
Unmapping the kernel '.bss' appears to break KVM initialisation on some
devices, breaking the boot on popular platforms such as RaspberryPi3 and
4.
Revert this change for now so that we can revisit it in future.
Reported-by: Mark Brown <broonie@kernel.org>
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/all/aicVyebkEMs6w6UV@sirena.co.uk
Link: https://lore.kernel.org/r/a1b27e97-182c-485d-a448-56c19c5de2c2@samsung.com
Signed-off-by: Will Deacon <will@kernel.org>
|
|
The generic implementations now suffice; remove the arm64 copies.
Link: https://lore.kernel.org/20260601084845.3792171-3-songmuchun@bytedance.com
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: Will Deacon <will@kernel.org>
Reviewed-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Oscar Salvador (SUSE) <osalvador@kernel.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
ptdesc_t sounds very similar to the core MM struct ptdesc which is actually
the memory descriptor for page table allocations. Hence rename this typedef
element as ptval_t instead for better clarity and separation.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: linux-efi@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Suggested-by: David Hildenbrand (Arm) <david@kernel.org>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
Marking the linear alias of data/bss invalid involves calling
set_memory_valid(), which calls split_kernel_leaf_mapping() under the
hood.
On BBML2_NOABORT capable systems, this may result in the need to
allocate page tables at a time when the generic memory allocation APIs
are not yet available, resulting in a splat like
WARNING: arch/arm64/mm/mmu.c:821 at split_kernel_leaf_mapping+0x15c/0x170, CPU#0: swapper/0
Modules linked in:
CPU: 0 UID: 0 PID: 0 Comm: swapper Not tainted 7.1.0-rc6 #1 PREEMPT(undef)
pstate: a04000c9 (NzCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : split_kernel_leaf_mapping+0x15c/0x170
lr : update_range_prot+0x40/0x128
sp : ffffc99ad3863c80
...
Call trace:
split_kernel_leaf_mapping+0x15c/0x170 (P)
update_range_prot+0x40/0x128
set_memory_valid+0x94/0xe0
mark_linear_data_alias_valid+0x54/0x68
map_mem+0x1fc/0x240
paging_init+0x48/0x210
setup_arch+0x274/0x338
start_kernel+0x98/0x538
__primary_switched+0x88/0x98
as reported by CKI automated testing.
So defer the boot-time call to mark_linear_data_alias_valid() to a later
time when page allocations can be made normally.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
Sashiko warns that the new pte_valid_noncont() macro is used in a manner
where the argument (which performs a READ_ONCE() of the descriptor) is
evaluated twice.
Drop the macro that we just added, and move the check into the newly
added users.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
Rename the .pgdir.bss section to .bss..pgtbl so that the compiler will
notice the leading ".bss" and mark it as NOBITS by default (rather than
PROGBITS, which would take up space in Image binary, forcing all of the
preceding BSS to be emitted into the image as well). This supersedes the
NOLOAD linker directive, which achieves the same thing, and can be
therefore be dropped.
Also, rename .pgdir to .pgtbl to be more generic, as page tables of
various levels will reside here.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
Since 5e8eb9aeeda3 ("arm64: mm: always call PTE/PMD ctor in
__create_pgd_mapping()") page-table allocation on ARM64 always calls
pagetable_{pte,pmd,pud,p4d}_ctor(). This sets the page_type to
PGTY_table, increments NR_PAGETABLE and possible allocates a PTL. However
the matching pagetable_dtor() calls were never added.
With DEBUG_VM enabled on kernel versions prior to v6.17 without
2dfcd1608f3a9 ("mm/page_alloc: let page freeing clear any set page type")
this leads to the following warning when freeing these pages due to
page->page_type sharing page->_mapcount:
BUG: Bad page state in process ... pfn:284fbb
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x284fbb
flags: 0x17fffc000000000(node=0|zone=2|lastcpupid=0x1ffff)
page_type: f2(table)
page dumped because: nonzero mapcount
Call trace:
bad_page+0x13c/0x160
__free_frozen_pages+0x6cc/0x860
___free_pages+0xf4/0x180
free_pages+0x54/0x80
free_hotplug_page_range.part.0+0x58/0x90
free_empty_tables+0x438/0x500
__remove_pgd_mapping.constprop.0+0x60/0xa8
arch_remove_memory+0x48/0x80
try_remove_memory+0x158/0x1d8
offline_and_remove_memory+0x138/0x180
It can also lead to leaking the ptl allocation if ALLOC_SPLIT_PTLOCKS is
defined and incorrect NR_PAGETABLE stats. Fix this by calling
pagetable_dtor() in free_hotplug_pgtable_page() prior to freeing the page
to undo the effects of calling pagetable_*_ctor().
Link: https://lore.kernel.org/20260521032730.2104017-1-apopple@nvidia.com
Fixes: 5e8eb9aeeda3 ("arm64: mm: always call PTE/PMD ctor in __create_pgd_mapping()")
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
The linear aliases of the kernel text and rodata are also mapped
read-only in the linear map. Given that the contents of these regions
are mostly identical to the version in the loadable image, mapping them
read-only and leaving their contents visible is a reasonable hardening
measure.
Data and bss, however, are now also mapped read-only but the contents of
these regions are more likely to contain data that we'd rather not leak.
So let's unmap these entirely in the linear map when the kernel is
running normally.
When going into hibernation or waking up from it, these regions need to
be mapped, so map the region initially, and toggle the valid bit so
map/unmap the region as needed.
Doing so is required because pages covering the kernel image are marked
as PageReserved, and therefore disregarded for snapshotting by the
hibernate logic unless they are mapped.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Kevin Brodsky <kevin.brodsky@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
On systems where the bootloader adheres to the original arm64 boot
protocol, the placement of the kernel in the physical address space is
highly predictable, and this makes the placement of its linear alias in
the kernel virtual address space equally predictable, given the lack of
randomization of the linear map.
The linear aliases of the kernel text and rodata regions are already
mapped read-only, but the kernel data and bss are mapped read-write in
this region. This is not needed, so map them read-only as well.
Note that the statically allocated kernel page tables do need to be
modifiable via the linear map, so leave these mapped read-write.
Reviewed-by: Kevin Brodsky <kevin.brodsky@arm.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
Now that the linear region mapping routines respect existing table
mappings and contiguous block and page mappings, it is no longer needed
to fiddle with the memblock tables to set and clear the NOMAP attribute
in order to omit text and rodata when creating the linear map.
Instead, map the kernel text and rodata alias first with the desired
initial attributes and granularity, so that the loop iterating over the
memblocks will not remap it in a manner that prevents it from being
remapped with updated attributes later.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Kevin Brodsky <kevin.brodsky@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
Move the fixmap and kasan page tables out of the BSS section, and place
them at the end of the image, right before the init_pg_dir section where
some of the other statically allocated page tables live.
These page tables are currently the only data objects in vmlinux that
are meant to be accessed via the kernel image's linear alias, and so
placing them together allows the remainder of the data/bss section to be
remapped read-only or unmapped entirely.
Reviewed-by: Kevin Brodsky <kevin.brodsky@arm.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
There are a few cases where we omit the contiguous hint for mappings
that start out as read-write and are remapped read-only later, on the
basis that manipulating live descriptors with the PTE_CONT attribute set
is unsafe. When support for the contiguous hint was added to the code,
the ARM ARM was ambiguous about this, and so we erred on the side of
caution.
In the meantime, this has been clarified [0], and regions that will be
remapped in their entirety, retaining the contiguous bit on all entries,
can use the contiguous hint both in the initial mapping as well as the
one that replaces it. Note that this requires that the logic that may be
called to remap overlapping regions respects existing valid descriptors
that have the contiguous bit cleared.
So omit the NO_CONT_MAPPINGS flag in places where it is unneeded.
[0] RJQQTC
For a TLB lookup in a contiguous region mapped by translation table entries that
have consistent values for the Contiguous bit, but have the OA, attributes, or
permissions misprogrammed, that TLB lookup is permitted to produce an OA, access
permissions, and memory attributes that are consistent with any one of the
programmed translation table values.
Reviewed-by: Kevin Brodsky <kevin.brodsky@arm.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
Now that the map_mem() routines respect existing page mappings and
contiguous granule sized blocks with the contiguous bit cleared, there
is no longer a reason to play tricks with the memblock NOMAP attribute.
Instead, the kfence pool can be allocated and mapped with page
granularity first, and this granularity will be respected when the rest
of DRAM is mapped later, even if block and contiguous mappings are
allowed for the remainder of those mappings.
Add the NO_EXEC_MAPPINGS flag to ensure that hierarchical XN attributes
are set on the intermediate page tables that are allocated when mapping
the pool.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Kevin Brodsky <kevin.brodsky@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
Currently, pgattr_change_is_safe() is overly pedantic when it comes to
descriptors with the contiguous hint attribute set, as it rejects
assignments even if the old and the new value are the same.
In fact, as per ARM ARM RJQQTC, manipulating descriptors with the
contiguous bit set is safe as long as the bit itself does not change
value, in the sense that no TLB conflict aborts or other exceptions may
be raised as a result. Inconsistent permission attributes within the
contiguous region may result in any of the alternatives to be taken to
apply to the entire region, which might be a programming error, but it
does not constitute an unsafe manipulation in terms of what
pgattr_change_is_safe() is intended to detect.
So drop the special PTE_CONT check, but still omit PTE_CONT from 'mask'
so that modifying the bit is still regarded as unsafe.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
Instead of blindly overwriting existing live entries regardless of the
value of their contiguous bit when mapping DRAM regions at
contiguous-hint granularity, check whether the contiguous region in
question contains any valid descriptors that have the contiguous bit
cleared, and in that case, leave the contiguous bit unset on the entire
region. This permits the logic of mapping the kernel's linear alias to
be simplified in a subsequent patch.
Note that this can only result in a misprogrammed contiguous bit (as per
ARM ARM RNGLXZ) if the region in question already contains a mix of
valid contiguous and valid non-contiguous descriptors, in which case it
was already misprogrammed to begin with.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
Instead of blindly overwriting an existing table entry when mapping DRAM
regions, take care not to replace a pre-existing table entry with a
block entry. This permits the logic of mapping the kernel's linear alias
to be simplified in a subsequent patch.
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
Sashiko reports:
| If pmd_set_huge() rejects an unsafe page table transition (such as
| mapping a different physical address over an existing block mapping),
| it returns 0 and leaves the page table entry unmodified.
|
| Because *pmdp remains unmodified, READ_ONCE(pmd_val(*pmdp)) will equal
| pmd_val(old_pmd). The transition from old_pmd to old_pmd is evaluated
| as safe by pgattr_change_is_safe(), so the BUG_ON never triggers.
|
| This allows invalid and unsafe mapping updates to be silently dropped
| instead of panicking, leaving stale memory mappings active while the
| caller assumes the update was successful.
The same applies to pud_set_huge() in alloc_init_pud().
Given how it is generally preferred to limp on rather than blow up the
system if an unexpected condition such as this one occurs, and the fact
that there are no known cases where this disparity results in real
problems, let's WARN on these failures rather than BUG, allowing the
system to survive to the point where it can actually report them.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
|
Karl Mehltretter
Linus Torvalds
Wei-Lin Chang
Will Deacon
Ard Biesheuvel
liulhong617
Vladimir Murzin
Linu Cherian
Lorenzo Stoakes (ARM)
Aneesh Kumar K.V (Arm)
Dev Jain
Mostafa Saleh
Richard Cheng
Mark Brown
Sang-Heon Jeon
Jinjie Ruan
Anshuman Khandual
Muchun Song
Alistair Popple