kernel/linux.git/arch/arm64/include, branch v7.1-rc5

Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

2026-05-22T13:53:11+00:00

Pull arm64 fixes from Catalin Marinas: - Handle probe on hinted conditional branch instructions. BC.cond instructions can be simulated in the same way as B.cond instructions, so extend the decode mask for B.cond to cover BC.cond - Flush the walk cache when unsharing PMD tables. Recent changes to huge_pmd_unshare() introduced mmu_gather::unshared_tables but the arm64 code was still treating the TLB flushing as only targeting leaf entries (TLBI VALE1IS). Fix it by using non-leaf-only instructions (TLBI VAE1IS) when tlb->unshared_tables is set * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: tlb: Flush walk cache when unsharing PMD tables arm64: probes: Handle probes on hinted conditional branch instructions

arm64: tlb: Flush walk cache when unsharing PMD tables

2026-05-22T10:13:51+00:00

When huge_pmd_unshare() is called to unshare a PMD table, the tlb_unshare_pmd_ptdesc() function sets tlb->unshared_tables=true but the aarch64 tlb_flush() only checked tlb->freed_tables to determine whether to use TLBF_NONE (vae1is, invalidates walk cache) or TLBF_NOWALKCACHE (vale1is, leaf-only). This caused the stale PMD page table entry to remain in the walk cache after unshare, potentially leading to incorrect page table walks. Fix by including unshared_tables in the check, so that when unsharing tables, TLBF_NONE is used and the walk cache is properly invalidated. Here is the detailed distinction between vae1is and vale1is: | Instruction Combination | Actual Invalidation Scope | | ------------------------ | --------------------------------------------------| | `VAE1IS` + TTL=`0` | All entries at all levels (full invalidation) | | `VAE1IS` + TTL=`2` (L2) | Non-leaf at Level 0/1 + leaf at Level 2 | | `VALE1IS` + TTL=`0` | Leaf entries at all levels (non-leaf not cleared) | | `VALE1IS` + TTL=`2` (L2) | Leaf entry at Level 2 only | Signed-off-by: Zeng Heng Fixes: 8ce720d5bd91 ("mm/hugetlb: fix excessive IPI broadcasts when unsharing PMD tables using mmu_gather") Cc: Signed-off-by: Catalin Marinas

Merge tag 'trace-ringbuffer-v7.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

2026-05-21T21:05:09+00:00

Pull ring-buffer fixes from Steven Rostedt: - Fix reporting MISSED EVENTS in trace iterator When the "trace" file is read with tracing enabled, if the writer were to pass the iterator reader, it resets, sets a "missed_events" flag and continues. The tracing output checks for missed events and if there are some, it prints out "[LOST EVENTS]" to let the user know events were dropped. But the clearing of the missed_events happened when the tracing system queried the ring buffer iterator about missed events. This was premature as the ring buffer is per CPU, and the tracing code reads all the CPU buffers and checks for missed events when it is read. If the CPU iterator that had missed events isn't printed next, the output for the LOST EVENTS is lost. Clear the missed_events flag when the iterator moves to the next event and not when the missed_events flag is queried. Also clear it on reset. - Flush and stop the persistent ring buffer on panic On panic the persistent ring buffer is used to debug what caused the panic. But on some architectures, it requires flushing the memory from cache, otherwise, the ring buffer persistent memory may not have the last events and this could also cause the ring buffer to be corrupted on the next boot. - Fix nr_subbufs initialization in simple_ring_buffer_init_mm The remote simple ring buffer meta data nr_subbufs is initialized too early and gets cleared later on, making it zero and not reflect the actual number of sub-buffers. - Fix unload_page for simple_ring_buffer init rollback On error, the pages loaded need to be unloaded. To unload a page it is expected that: page = load_page(va); -> unload_page(page). But the code was doing: unload_page(va) and not unload_page(page). - Create output file from cmd_check_undefined The check for undefined symbols checks if the file *.o.checked exists and if so it skips doing the work. But the *.o.checked file never was created making every build do the work even when it was already done previously. * tag 'trace-ringbuffer-v7.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing: Create output file from cmd_check_undefined tracing: Fix unload_page for simple_ring_buffer init rollback tracing: Fix nr_subbufs initialization in simple_ring_buffer_init_mm() ring-buffer: Flush and stop persistent ring buffer on panic ring-buffer: Fix reporting of missed events in iterator

ring-buffer: Flush and stop persistent ring buffer on panic

2026-05-21T12:20:58+00:00

On real hardware, panic and machine reboot may not flush hardware cache to memory. This means the persistent ring buffer, which relies on a coherent state of memory, may not have its events written to the buffer and they may be lost. Moreover, there may be inconsistency with the counters which are used for validation of the integrity of the persistent ring buffer which may cause all data to be discarded. To avoid this issue, stop recording of the ring buffer on panic and flush the cache of the ring buffer's memory. Fixes: e645535a954a ("tracing: Add option to use memmapped memory for trace boot instance") Cc: stable@vger.kernel.org Cc: Will Deacon Cc: Mathieu Desnoyers Cc: Ian Rogers Link: https://patch.msgid.link/177751969602.2136606.12031934362587643488.stgit@mhiramat.tok.corp.google.com Signed-off-by: Masami Hiramatsu (Google) Acked-by: Catalin Marinas Acked-by: Geert Uytterhoeven Signed-off-by: Steven Rostedt

Merge tag 'mm-hotfixes-stable-2026-05-18-21-07' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2026-05-19T14:49:33+00:00

Pull misc fixes from Andrew Morton: "14 hotfixes. 9 are for MM. 10 are cc:stable and the remainder are for post-7.1 issues or aren't deemed suitable for backporting. There's a two-patch MAINTAINERS series from Mike Rapoport which updates us for the new KEXEC/KDUMP/crash/LUO/etc arrangements. And another two-patch series from Muchun Song to fix a couple of memory-hotplug issues. Otherwise singletons, please see the changelogs for details" * tag 'mm-hotfixes-stable-2026-05-18-21-07' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: mm/memory: fix spurious warning when unmapping device-private/exclusive pages mm: fix __vm_normal_page() to handle missing support for pmd_special()/pud_special() drivers/base/memory: fix memory block reference leak in poison accounting mm/memory_hotplug: fix memory block reference leak on remove lib: kunit_iov_iter: fix test fail on powerpc mm/page_alloc: fix initialization of tags of the huge zero folio with init_on_free MAINTAINERS: add kexec@ list to LIVE UPDATE ENTRY MAINTAINERS: add tree for KDUMP and KEXEC selftests/mm: run_vmtests.sh: fix destructive tests invocation scripts/gdb: slab: update field names of struct kmem_cache scripts/gdb: mm: cast untyped symbols in x86_page_ops mm/damon: fix damos_stat tracepoint format for sz_applied mm/damon/sysfs-schemes: call missing mem_cgroup_iter_break() mm/migrate_device: fix spinlock leak in migrate_vma_insert_huge_pmd_page

arm64: probes: Handle probes on hinted conditional branch instructions

2026-05-19T13:54:08+00:00

BC.cond instructions introduced by FEAT_HBC cannot be executed out-of-line, like other branch instructions. However, they can be simulated in the same way as B.cond instructions. Extend the B.cond decoder mask to match BC.cond instructions as well, and handle them using the existing B.cond simulation path. Fixes: 7f86d128e437 ("arm64: add HWCAP for FEAT_HBC (hinted conditional branches)") Cc: Signed-off-by: Vladimir Murzin Signed-off-by: Catalin Marinas

mm/page_alloc: fix initialization of tags of the huge zero folio with init_on_free

2026-05-14T00:40:02+00:00

__GFP_ZEROTAGS semantics are currently a bit weird, but effectively this flag is only ever set alongside __GFP_ZERO and __GFP_SKIP_KASAN. If we run with init_on_free, we will zero out pages during __free_pages_prepare(), to skip zeroing on the allocation path. However, when allocating with __GFP_ZEROTAG set, post_alloc_hook() will consequently not only skip clearing page content, but also skip clearing tag memory. Not clearing tags through __GFP_ZEROTAGS is irrelevant for most pages that will get mapped to user space through set_pte_at() later: set_pte_at() and friends will detect that the tags have not been initialized yet (PG_mte_tagged not set), and initialize them. However, for the huge zero folio, which will be mapped through a PMD marked as special, this initialization will not be performed, ending up exposing whatever tags were still set for the pages. The docs (Documentation/arch/arm64/memory-tagging-extension.rst) state that allocation tags are set to 0 when a page is first mapped to user space. That no longer holds with the huge zero folio when init_on_free is enabled. Fix it by decoupling __GFP_ZEROTAGS from __GFP_ZERO, passing to tag_clear_highpages() whether we want to also clear page content. Invert the meaning of the tag_clear_highpages() return value to have clearer semantics. Reproduced with the huge zero folio by modifying the check_buffer_fill arm64/mte selftest to use a 2 MiB area, after making sure that pages have a non-0 tag set when freeing (note that, during boot, we will not actually initialize tags, but only set KASAN_TAG_KERNEL in the page flags). $ ./check_buffer_fill 1..20 ... not ok 17 Check initial tags with private mapping, sync error mode and mmap memory not ok 18 Check initial tags with private mapping, sync error mode and mmap/mprotect memory ... This code needs more cleanups; we'll tackle that next, like decoupling __GFP_ZEROTAGS from __GFP_SKIP_KASAN. [akpm@linux-foundation.org: s/__GPF_ZERO/__GFP_ZERO/, per David] Link: https://lore.kernel.org/20260421-zerotags-v2-1-05cb1035482e@kernel.org Fixes: adfb6609c680 ("mm/huge_memory: initialise the tags of the huge zero folio") Signed-off-by: David Hildenbrand (Arm) Reviewed-by: Catalin Marinas Tested-by: Lance Yang Cc: Brendan Jackman Cc: Dev Jain Cc: Johannes Weiner Cc: Liam Howlett Cc: Lorenzo Stoakes (Oracle) Cc: Mark Brown Cc: Michal Hocko Cc: Mike Rapoport Cc: Ryan Roberts Cc: Suren Baghdasaryan Cc: Will Deacon Cc: Zi Yan Cc: Signed-off-by: Andrew Morton

KVM: arm64: Make EL2 exception entry and exit context-synchronization events

2026-05-07T13:12:41+00:00

SCTLR_EL2.EIS and SCTLR_EL2.EOS control whether exception entry and exit at EL2 are Context Synchronisation Events (CSEs). Per ARM DDI 0487 M.b D24.2.175 (p. D24-9754): - !FEAT_ExS: the bit is RES1, so the entry/exit is unconditionally a CSE. - FEAT_ExS: the reset value is architecturally UNKNOWN; software must set the bit to make the entry/exit a CSE. INIT_SCTLR_EL2_MMU_ON in arch/arm64/include/asm/sysreg.h sets neither bit. KVM/arm64 hot paths rely on ERET from EL2 being a CSE, and on synchronous EL1->EL2 entry being a CSE, to elide explicit ISBs after MSRs to context-switching system registers (HCR_EL2, ZCR_EL2, ptrauth keys, etc.). On FEAT_ExS hardware those reliances are not architecturally backed unless EOS=1 (and, for entry, EIS=1). Until commit 0a35bd285f43 ("arm64: Convert SCTLR_EL2 to sysreg infrastructure"), SCTLR_EL2_RES1 was a hand-rolled mask that included BIT(11) (EOS) and BIT(22) (EIS), so INIT_SCTLR_EL2_MMU_ON was setting both unconditionally. The conversion made SCTLR_EL2_RES1 auto-generated; because the sysreg tooling only models unconditionally-RES1 fields and EIS/EOS are RES1 only when FEAT_ExS is absent, the auto-generated mask is UL(0). The seven other bits dropped from the old mask (positions 4, 5, 16, 18, 23, 28, 29) are unconditionally RES1 in the E2H=0 SCTLR_EL2 layout per DDI 0487 M.b D24.2.175, so dropping them is harmless. EIS and EOS are the only bits whose semantics changed for FEAT_ExS hardware and where the kernel relies on the value being 1. Make the guarantee explicit: include SCTLR_ELx_EIS | SCTLR_ELx_EOS in INIT_SCTLR_EL2_MMU_ON so that EL2 exception entry and exit are unconditionally CSEs regardless of whether FEAT_ExS is implemented. This matches the pairing in arch/arm64/kvm/config.c which treats EIS and EOS together as RES1 under !FEAT_ExS. Fixes: 0a35bd285f43 ("arm64: Convert SCTLR_EL2 to sysreg infrastructure") Reviewed-by: Yuan Yao Assisted-by: Gemini:gemini-3.1-pro review-prompts Signed-off-by: Fuad Tabba Link: https://patch.msgid.link/20260501112149.2824881-2-tabba@google.com Signed-off-by: Marc Zyngier

KVM: arm64: nv: Consider the DS bit when translating TCR_EL2

2026-05-06T16:08:39+00:00

When running an nVHE L1, TCR_EL2 is mapped to TCR_EL1. Writes to the register are trapped and written to TCR_EL1 after a translation. Booting an nVHE L1 with 52-bit VA isn't working because the translation was ignoring the DS bit set by the guest, hence causing repeating level 0 faults. Add it in the translation function. Signed-off-by: Wei-Lin Chang Link: https://patch.msgid.link/20260505144735.1496530-1-weilin.chang@arm.com Signed-off-by: Marc Zyngier

Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

2026-05-01T23:32:42+00:00

Pull arm64 fixes from Catalin Marinas: - Avoid writing an uninitialised stack variable to POR_EL0 on sigreturn if the poe_context record is absent - Reserve one more page for the early 4K-page kernel mapping to cover the extra [_text, _stext) split introduced by the non-executable read-only mapping - Force the arch_local_irq_*() wrappers to be __always_inline so that noinstr entry and idle paths cannot call out-of-line, instrumentable copies - Fix potential sign extension in the arm64 SCS unwinder's DWARF advance_loc4 decoding - Tolerate arm64 ACPI platforms with only WFI and no deeper PSCI idle states, restoring cpuidle registration on such systems - Include the UAPI header in the arm64 GCS libc test rather than carrying a duplicate struct user_gcs definition (the original #ifdef NT_ARM_GCS was wrong to cover the structure definition as it would be masked out if the toolchain defined it) * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: signal: Preserve POR_EL0 if poe_context is missing arm64: Reserve an extra page for early kernel mapping kselftest/arm64: Include for user_gcs definition ACPI: arm64: cpuidle: Tolerate platforms with no deep PSCI idle states arm64/irqflags: __always_inline the arch_local_irq_*() helpers arm64/scs: Fix potential sign extension issue of advance_loc4