kernel/linux.git/arch/arm64, branch v7.0.14

arm64/entry: Fix arm64-specific rseq brokenness

2026-06-27T10:07:38+00:00

commit 411c1cf430392c905e39f12bc305dd994da0b426 upstream. Mathias Stearn reports that since v6.19, there are two big issues affecting rseq: (1) On arm64 specifically, rseq critical sections aren't aborted when they should be. (2) The 'cpu_id_start' field is no longer written by the kernel in all cases it used to be, including some cases where TCMalloc depends on the kernel clobbering the field. This patch fixes issue #1. This patch DOES NOT fix issue #2, which will need to be addressed by other patches. The arm64-specific brokenness is a result of commits: 2fc0e4b4126c ("rseq: Record interrupt from user space") 39a167560a61 ("rseq: Optimize event setting") The first commit failed to add a call to rseq_note_user_irq_entry() on arm64. Thus arm64 never sets rseq_event::user_irq to record that it may be necessary to abort an active rseq critical section upon return to userspace. On its own, this commit had no functional impact as the value of rseq_event::user_irq was not consumed. The second commit relied upon rseq_event::user_irq to determine whether or not to bother to perform rseq work when returning to userspace. As rseq_event::user_irq wasn't set on arm64, this work would be skipped, and consequently an active rseq critical section would not be aborted. Fix this by giving arm64 syscall-specific entry/exit paths, and performing the relevant logic in syscall and non-syscall paths, including calling rseq_note_user_irq_entry() for non-syscall entry. Currently arm64 cannot use syscall_enter_from_user_mode(), syscall_exit_to_user_mode(), and irqentry_exit_to_user_mode(), due to ordering constraints with exception masking, and risk of ABI breakage for syscall tracing/audit/etc. For the moment the entry/exit logic is left as arm64-specific, directly using enter_from_user_mode() and exit_to_user_mode(), but mirroring the generic code. I intend to follow up with refactoring/cleanup, as we did for kernel mode entry paths in commit: 041aa7a85390 ("entry: Split preemption from irqentry_exit_to_kernel_mode()") ... which will allow arm64 to use the GENERIC_IRQ_ENTRY functions directly. Fixes: 39a167560a61 ("rseq: Optimize event setting") Reported-by: Mathias Stearn Signed-off-by: Mark Rutland Signed-off-by: Peter Zijlstra (Intel) Acked-by: Catalin Marinas Link: https://lore.kernel.org/regressions/CAHnCjA25b+nO2n5CeifknSKHssJpPrjnf+dtr7UgzRw4Zgu=oA@mail.gmail.com/ Link: https://patch.msgid.link/20260508142023.3268622-1-mark.rutland@arm.com [Mark: fix conflicts in entry-common.c & irq-entry-common.h] Signed-off-by: Mark Rutland Signed-off-by: Sasha Levin

arm64: errata: Mitigate TLBI errata on Microsoft Azure Cobalt 100 CPU

2026-06-19T11:48:13+00:00

commit 1940e70a8144bf75e6df26bf6f600862ea7f7ea1 upstream. Commit fb091ff39479 ("arm64: Subscribe Microsoft Azure Cobalt 100 to ARM Neoverse N2 errata") states that Microsoft Azure Cobalt 100 CPU "is a Microsoft implemented CPU based on r0p0 of the ARM Neoverse N2 CPU, and therefore suffers from all the same errata.". So enable the workaround for the latest broadcast TLB invalidation bug on these parts. Signed-off-by: Will Deacon [Mark: backport to v7.0.y] Signed-off-by: Mark Rutland Signed-off-by: Greg Kroah-Hartman

arm64: errata: Mitigate TLBI errata on NVIDIA Olympus CPU

2026-06-19T11:48:13+00:00

commit ec7216f92e4ebd485b1c6dc6aa3f6064b71a5768 upstream. NVIDIA Olympus cores are affected by the TLBI completion issue tracked as CVE-2025-10263. The existing ARM64_ERRATUM_4118414 handling already uses ARM64_WORKAROUND_REPEAT_TLBI to issue an additional broadcast TLBI;DSB sequence and ensure affected memory write effects are globally observed. Add MIDR_NVIDIA_OLYMPUS to the repeat-TLBI match list so the same mitigation is enabled on affected Olympus systems. Also document the NVIDIA Olympus erratum in the arm64 silicon errata table and list it in the Kconfig help text. Signed-off-by: Shanker Donthineni Cc: Catalin Marinas Cc: Will Deacon Cc: Mark Rutland Acked-by: Mark Rutland Signed-off-by: Will Deacon [Mark: backport to v7.0.y] Signed-off-by: Mark Rutland Signed-off-by: Greg Kroah-Hartman

arm64: errata: Mitigate TLBI errata on various Arm CPUs

2026-06-19T11:48:13+00:00

commit cfd391e74134db664feb499d43af286380b10ba8 upstream. A number of CPUs developed by Arm suffer from errata whereby a broadcast TLBI;DSB sequence may complete before the global observation of writes which are translated by an affected TLB entry. These errata ONLY affect the completion of memory accesses which have been translated by an invalidated TLB entry, and these errata DO NOT affect the actual invalidation of TLB entries. TLB entries are removed correctly. This issue has been assigned CVE ID CVE-2025-10263. To mitigate this issue, Arm recommends that software follows any affected TLBI;DSB sequence with an additional TLBI;DSB, which will ensure that all memory write effects affected by the first TLBI have been globally observed. The additional TLBI can use any operation that is broadcast to affected CPUs, and the additional DSB can use any option that is sufficient to complete the additional TLBI. The ARM64_WORKAROUND_REPEAT_TLBI workaround is sufficient to mitigate the issue. Enable this workaround for affected CPUs, and update the silicon errata documentation accordingly. Note that due to the manner in which Arm develops IP and tracks errata, some CPUs share a common erratum number. Signed-off-by: Mark Rutland Cc: Catalin Marinas Cc: Will Deacon Signed-off-by: Will Deacon [Mark: backport to v7.0.y] Signed-off-by: Mark Rutland Signed-off-by: Greg Kroah-Hartman

arm64: cputype: Add C1-Premium definitions

2026-06-19T11:48:13+00:00

commit d28413bfc5a255957241f1df5d7fd0c2cd74fe18 upstream. Add cputype definitions for C1-Premium. These will be used for errata detection in subsequent patches. These values can be found in the C1-Premium TRM: https://developer.arm.com/documentation/109416/0100/ ... in section A.5.1 ("MIDR_EL1, Main ID Register"). Signed-off-by: Mark Rutland Cc: Catalin Marinas Cc: Will Deacon Signed-off-by: Will Deacon [Mark: backport to v7.0.y] Signed-off-by: Mark Rutland Signed-off-by: Greg Kroah-Hartman

arm64: cputype: Add C1-Ultra definitions

2026-06-19T11:48:12+00:00

commit 60349e64a6c65f9f0aa118af711b3c7e137f07ff upstream. Add cputype definitions for C1-Ultra. These will be used for errata detection in subsequent patches. These values can be found in the C1-Ultra TRM: https://developer.arm.com/documentation/108014/0100/ ... in section A.5.1 ("MIDR_EL1, Main ID Register"). Signed-off-by: Mark Rutland Cc: Catalin Marinas Cc: Will Deacon Signed-off-by: Will Deacon [Mark: backport to v7.0.y] Signed-off-by: Mark Rutland Signed-off-by: Greg Kroah-Hartman

arm64: mm: call pagetable dtor when freeing hot-removed page tables

2026-06-19T11:48:01+00:00

commit c594b83457ccdee76d458416fb3bc9348a37592f upstream. 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 Cc: Catalin Marinas Cc: David Hildenbrand Cc: Will Deacon Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

KVM: arm64: Restore POR_EL0 access to host EL0

2026-06-19T11:47:58+00:00

commit cbaffe843a942c0d3102e0f9bce0e72b029b2594 upstream. CPTR_EL2.E0POE was being cleared in __deactivate_cptr_traps_vhe(), which meant that any accesses to POR_EL0 from host EL0 would trap and be reported to userspace as an Illegal instruction. This would happen after running any VM, regardless if it used POE or not. Signed-off-by: Joey Gouly Link: https://sashiko.dev/#/patchset/20260602155430.2088142-1-maz@kernel.org?part=1 Link: https://patch.msgid.link/20260604105434.2297268-1-joey.gouly@arm.com Signed-off-by: Marc Zyngier Cc: stable@vger,kernel.org Signed-off-by: Greg Kroah-Hartman

KVM: arm64: Correctly identify executable PTEs at stage-2

2026-06-19T11:47:58+00:00

commit 17f073f78fc43280891ecde8f8ec3f84f98bb37c upstream. KVM invalidates the I-cache before installing an executable PTE on implementations without DIC. Unfortunately, support for FEAT_XNX broke this check as KVM_PTE_LEAF_ATTR_HI_S2_XN was expanded to a bitfield. Fix it by reusing kvm_pgtable_stage2_pte_prot() and testing the abstract permission bits instead. Fixes: 2608563b466b ("KVM: arm64: Add support for FEAT_XNX stage-2 permissions") Reported-by: Sashiko (gemini/gemini-3.1-pro-preview) Signed-off-by: Oliver Upton Reviewed-by: Wei-Lin Chang Link: https://patch.msgid.link/20260602165901.52800-3-oupton@kernel.org Signed-off-by: Marc Zyngier Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

KVM: arm64: nv: Fix handling of XN[0] when !FEAT_XNX

2026-06-19T11:47:58+00:00

commit 49b32ddb87a3a109afecea89e55d70f73956b8bc upstream. XN has already been extracted from its bitfield position so using FIELD_PREP() on the mask that clears XN[0] is completely broken, having the effect of unconditionally granting execute permissions... Fix the obvious mistake by manipulating the right bit. Cc: stable@vger.kernel.org Fixes: d93febe2ed2e ("KVM: arm64: nv: Forward FEAT_XNX permissions to the shadow stage-2") Reviewed-by: Wei-Lin Chang Signed-off-by: Oliver Upton Link: https://patch.msgid.link/20260602165901.52800-2-oupton@kernel.org Signed-off-by: Marc Zyngier Signed-off-by: Greg Kroah-Hartman