kernel/linux.git/arch/riscv, branch v6.18.38

riscv: kfence: Call mark_new_valid_map() for kfence_unprotect()

2026-07-04T11:44:20+00:00

commit 8d6c8c40e733b3fcaf92fed0a078bba2f6941a3b upstream. In kfence_protect_page(), which kfence_unprotect() calls, we cannot send IPIs to other CPUs to ask them to flush TLB. This may lead to those CPUs spuriously faulting on a recently allocated kfence object despite it being valid, leading to false positive use-after-free reports. Fix this by calling mark_new_valid_map() so that the page fault handling code path notices the spurious fault and flushes TLB then retries the access. Update the comment in handle_exception to indicate that new_valid_map_cpus_check also handles kfence_unprotect() spurious faults. Note that kfence_protect() has the same stale TLB entries problem, but that leads to false negatives, which is fine with kfence. Cc: stable@vger.kernel.org Reported-by: Yanko Kaneti Fixes: b3431a8bb336 ("riscv: Fix IPIs usage in kfence_protect_page()") Signed-off-by: Vivian Wang Link: https://patch.msgid.link/20260303-handle-kfence-protect-spurious-fault-v2-2-f80d8354d79d@iscas.ac.cn Signed-off-by: Paul Walmsley Signed-off-by: Greg Kroah-Hartman

riscv: mm: Extract helper mark_new_valid_map()

2026-07-04T11:44:20+00:00

commit 9ee25d0a70ff4494b4e1d266b962d0a574ef318a upstream. In preparation of a future patch using the same mechanism for non-vmalloc addresses, extract the mark_new_valid_map() helper from flush_cache_vmap(). No functional change intended. Cc: stable@vger.kernel.org Signed-off-by: Vivian Wang Link: https://patch.msgid.link/20260303-handle-kfence-protect-spurious-fault-v2-1-f80d8354d79d@iscas.ac.cn Signed-off-by: Paul Walmsley Signed-off-by: Greg Kroah-Hartman

Disable -Wattribute-alias for clang-23 and newer

2026-06-09T10:28:37+00:00

commit 175db11786bde9061db526bf1ac5107d915f5163 upstream. Clang recently added support for -Wattribute-alias [1], which results in the same warnings that necessitated commit bee20031772a ("disable -Wattribute-alias warning for SYSCALL_DEFINEx()") for GCC. kernel/time/itimer.c:325:1: error: alias and aliasee have different types 'long (unsigned int)' and 'long (typeof (__builtin_choose_expr((__builtin_types_compatible_p(typeof ((unsigned int)0), typeof (0LL)) || __builtin_types_compatible_p(typeof ((unsigned int)0), typeof (0ULL))), 0LL, 0L)))' (aka 'long (long)') [-Werror,-Wattribute-alias] 325 | SYSCALL_DEFINE1(alarm, unsigned int, seconds) | ^ include/linux/syscalls.h:225:36: note: expanded from macro 'SYSCALL_DEFINE1' 225 | #define SYSCALL_DEFINE1(name, ...) SYSCALL_DEFINEx(1, _##name, __VA_ARGS__) | ^ include/linux/syscalls.h:236:2: note: expanded from macro 'SYSCALL_DEFINEx' 236 | __SYSCALL_DEFINEx(x, sname, __VA_ARGS__) | ^ include/linux/syscalls.h:251:18: note: expanded from macro '__SYSCALL_DEFINEx' 251 | __attribute__((alias(__stringify(__se_sys##name)))); \ | ^ kernel/time/itimer.c:325:1: note: aliasee is declared here include/linux/syscalls.h:225:36: note: expanded from macro 'SYSCALL_DEFINE1' 225 | #define SYSCALL_DEFINE1(name, ...) SYSCALL_DEFINEx(1, _##name, __VA_ARGS__) | ^ include/linux/syscalls.h:236:2: note: expanded from macro 'SYSCALL_DEFINEx' 236 | __SYSCALL_DEFINEx(x, sname, __VA_ARGS__) | ^ include/linux/syscalls.h:255:18: note: expanded from macro '__SYSCALL_DEFINEx' 255 | asmlinkage long __se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__)) \ | ^ :16:1: note: expanded from here 16 | __se_sys_alarm | ^ Disable the warnings in the same way for clang-23 and newer. Disable the warning about unknown warning options to avoid breaking the build for versions of clang-23 that do not have -Wattribute-alias, such as ones deployed by vendors like Android or CI systems or when bisecting LLVM between llvmorg-23-init and release/23.x. Cc: stable@vger.kernel.org Closes: https://github.com/ClangBuiltLinux/linux/issues/2163 Link: https://github.com/llvm/llvm-project/commit/40da6920a0d71d49dfa2392b09153600b0759f5e [1] Link: https://patch.msgid.link/20260515-syscall-disable-attribute-alias-for-clang-v1-1-9a9d95d41df6@kernel.org Signed-off-by: Nathan Chancellor Signed-off-by: Greg Kroah-Hartman

riscv: mm: Fixup no5lvl failure when vaddr is invalid

2026-06-01T15:50:52+00:00

[ Upstream commit db909bd7986c10da074917af3dae83a60fa65093 ] Unlike no4lvl, no5lvl still continues to detect satp, which requires va=pa mapping. When pa=0x800000000000, no5lvl would fail in Sv48 mode due to an illegal VA value of 0x800000000000. So, prevent detecting the satp flow for no5lvl, when vaddr is invalid. Add the is_vaddr_valid() function for checking. Fixes: 26e7aacb83df ("riscv: Allow to downgrade paging mode from the command line") Cc: Alexandre Ghiti Cc: Björn Töpel Signed-off-by: Guo Ren (Alibaba DAMO Academy) Tested-by: Fangyu Yu Link: https://patch.msgid.link/20260125055212.433163-1-guoren@kernel.org [pjw@kernel.org: cleaned up commit message] Signed-off-by: Paul Walmsley Signed-off-by: Sasha Levin

riscv: errata: Fix bitwise vs logical AND in MIPS errata patching

2026-06-01T15:50:52+00:00

[ Upstream commit 4d2b03699460b8fd5df34408a03a84a1a7ff8aa1 ] The condition checking whether a specific errata needs patching uses logical AND (&&) instead of bitwise AND (&). Since logical AND only checks that both operands are non-zero, this causes all errata patches to be applied whenever any single errata is detected, rather than only applying the matching one. The SiFive errata implementation correctly uses bitwise AND for the same check. Fixes: 0b0ca959d206 ("riscv: errata: Fix the PAUSE Opcode for MIPS P8700") Signed-off-by: Michael Neuling Assisted-by: Cursor:claude-4.6-opus-high-thinking Link: https://patch.msgid.link/20260409091143.1348853-2-mikey@neuling.org [pjw@kernel.org: fixed checkpatch warning] Signed-off-by: Paul Walmsley Signed-off-by: Sasha Levin

riscv: kvm: return SBI_ERR_FAILURE for pmu_event_info() when OOM

2026-06-01T15:50:46+00:00

commit 0e9d0e7a7c78db7aa1c13796c65cfe0aefa54a5b upstream. kvm_riscv_vcpu_pmu_event_info() returned -ENOMEM from the SBI extension handler, which caused kvm_riscv_vcpu_sbi_ecall() to abort KVM_RUN and surface the error to userspace instead of completing the ECALL with a negative SBI error in a0. Use SBI_ERR_FAILURE and the normal retdata path, matching other PMU handlers and kvm_sbi_ext_pmu_handler comment. Fixes: e309fd113b9f ("RISC-V: KVM: Implement get event info function") Cc: stable@vger.kernel.org Signed-off-by: Osama Abdelkader Reviewed-by: Anup Patel Link: https://lore.kernel.org/r/20260514173642.41448-2-osama.abdelkader@gmail.com Signed-off-by: Anup Patel Signed-off-by: Greg Kroah-Hartman

riscv: kvm: return SBI_ERR_FAILURE for pmu_snapshot_set_shmem() when OOM

2026-06-01T15:50:46+00:00

commit 0835ee26938e15eccd70f7d33da386b6490f9449 upstream. kvm_riscv_vcpu_pmu_snapshot_set_shmem() returned -ENOMEM from the SBI extension handler, which caused kvm_riscv_vcpu_sbi_ecall() to abort KVM_RUN and surface the error to userspace instead of ompleting the ECALL with a negative SBI error in a0. Use SBI_ERR_FAILURE and the normal retdata path, matching other PMU handlers and kvm_sbi_ext_pmu_handler comment. Fixes: c2f41ddbcdd7 ("RISC-V: KVM: Implement SBI PMU Snapshot feature") Cc: stable@vger.kernel.org Signed-off-by: Osama Abdelkader Reviewed-by: Anup Patel Link: https://lore.kernel.org/r/20260514173642.41448-1-osama.abdelkader@gmail.com Signed-off-by: Anup Patel Signed-off-by: Greg Kroah-Hartman

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

2026-06-01T15:50:44+00:00

commit a494d3c8d5392bcdff83c2a593df0c160ff9f322 upstream. 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 Signed-off-by: Greg Kroah-Hartman

bpf, riscv: Remove redundant bpf_flush_icache() after pack allocator finalize

2026-05-23T11:06:51+00:00

[ Upstream commit 46ee1342b887c9387a933397d846ff6c9584322c ] bpf_flush_icache() calls flush_icache_range() to clean the data cache and invalidate the instruction cache for the JITed code region. However, since commit 48a8f78c50bd ("bpf, riscv: use prog pack allocator in the BPF JIT"), this flush is redundant. bpf_jit_binary_pack_finalize() copies the JITed instructions to the ROX region via bpf_arch_text_copy() -> patch_text_nosync(), and patch_text_nosync() already calls flush_icache_range() on the written range. The subsequent bpf_flush_icache() repeats the same cache maintenance on an overlapping range. Remove the redundant bpf_flush_icache() call and its now-unused definition. Fixes: 48a8f78c50bd ("bpf, riscv: use prog pack allocator in the BPF JIT") Acked-by: Song Liu Signed-off-by: Puranjay Mohan Reviewed-by: Pu Lehui Tested-by: Paul Chaignon Link: https://lore.kernel.org/r/20260413191111.3426023-3-puranjay@kernel.org Signed-off-by: Alexei Starovoitov Signed-off-by: Sasha Levin

riscv: kvm: fix vector context allocation leak

2026-05-14T13:30:20+00:00

commit b7c958d7c1eb1cb9b2be7b5ee4129fcd66cec978 upstream. When the second kzalloc (host_context.vector.datap) fails in kvm_riscv_vcpu_alloc_vector_context, the first allocation (guest_context.vector.datap) is leaked. Free it before returning. Fixes: 0f4b82579716 ("riscv: KVM: Add vector lazy save/restore support") Cc: stable@vger.kernel.org Signed-off-by: Osama Abdelkader Reviewed-by: Andy Chiu Link: https://lore.kernel.org/r/20260316151612.13305-1-osama.abdelkader@gmail.com Signed-off-by: Anup Patel Signed-off-by: Greg Kroah-Hartman