kernel/linux.git/arch/riscv, branch v6.6.132

riscv: Sanitize syscall table indexing under speculation

2026-03-25T10:06:00+00:00

[ Upstream commit 25fd7ee7bf58ac3ec7be3c9f82ceff153451946c ] The syscall number is a user-controlled value used to index into the syscall table. Use array_index_nospec() to clamp this value after the bounds check to prevent speculative out-of-bounds access and subsequent data leakage via cache side channels. Signed-off-by: Lukas Gerlach Link: https://patch.msgid.link/20251218191332.35849-3-lukas.gerlach@cispa.de Signed-off-by: Paul Walmsley [ Added linux/nospec.h for array_index_nospec() to make sure compile without error ] Signed-off-by: Leon Chen Signed-off-by: Greg Kroah-Hartman

riscv: compat: fix COMPAT_UTS_MACHINE definition

2026-02-06T15:48:24+00:00

commit 0ea05c4f7527a98f5946f96c829733788934311d upstream. The COMPAT_UTS_MACHINE for riscv was incorrectly defined as "riscv". Change it to "riscv32" to reflect the correct 32-bit compat name. Fixes: 06d0e3723647 ("riscv: compat: Add basic compat data type implementation") Cc: stable@vger.kernel.org Signed-off-by: Han Gao Reviewed-by: Guo Ren (Alibaba Damo Academy) Link: https://patch.msgid.link/20260127190711.2264664-1-gaohan@iscas.ac.cn Signed-off-by: Paul Walmsley Signed-off-by: Greg Kroah-Hartman

riscv: Replace function-like macro by static inline function

2026-01-17T15:30:02+00:00

commit 121f34341d396b666d8a90b24768b40e08ca0d61 upstream. The flush_icache_range() function is implemented as a "function-like macro with unused parameters", which can result in "unused variables" warnings. Replace the macro with a static inline function, as advised by Documentation/process/coding-style.rst. Fixes: 08f051eda33b ("RISC-V: Flush I$ when making a dirty page executable") Signed-off-by: Björn Töpel Link: https://lore.kernel.org/r/20250419111402.1660267-1-bjorn@kernel.org Signed-off-by: Palmer Dabbelt Signed-off-by: Ron Economos Signed-off-by: Greg Kroah-Hartman

riscv: uprobes: Add missing fence.i after building the XOL buffer

2026-01-17T15:30:00+00:00

[ Upstream commit 7d1d19a11cfbfd8bae1d89cc010b2cc397cd0c48 ] The XOL (execute out-of-line) buffer is used to single-step the replaced instruction(s) for uprobes. The RISC-V port was missing a proper fence.i (i$ flushing) after constructing the XOL buffer, which can result in incorrect execution of stale/broken instructions. This was found running the BPF selftests "test_progs: uprobe_autoattach, attach_probe" on the Spacemit K1/X60, where the uprobes tests randomly blew up. Reviewed-by: Guo Ren Fixes: 74784081aac8 ("riscv: Add uprobes supported") Signed-off-by: Björn Töpel Link: https://lore.kernel.org/r/20250419111402.1660267-2-bjorn@kernel.org Signed-off-by: Palmer Dabbelt Signed-off-by: Rahul Sharma Signed-off-by: Greg Kroah-Hartman

RISC-V: KVM: Fix guest page fault within HLV* instructions

2026-01-11T14:21:29+00:00

[ Upstream commit 974555d6e417974e63444266e495a06d06c23af5 ] When executing HLV* instructions at the HS mode, a guest page fault may occur when a g-stage page table migration between triggering the virtual instruction exception and executing the HLV* instruction. This may be a corner case, and one simpler way to handle this is to re-execute the instruction where the virtual instruction exception occurred, and the guest page fault will be automatically handled. Fixes: b91f0e4cb8a3 ("RISC-V: KVM: Factor-out instruction emulation into separate sources") Signed-off-by: Fangyu Yu Reviewed-by: Anup Patel Link: https://lore.kernel.org/r/20251121133543.46822-1-fangyu.yu@linux.alibaba.com Signed-off-by: Anup Patel Signed-off-by: Sasha Levin

riscv: acpi: avoid errors caused by probing DT devices when ACPI is used

2025-11-24T09:29:57+00:00

[ Upstream commit 69a8b62a7aa1e54ff7623064f6507fa29c1d0d4e ] Similar to the ARM64 commit 3505f30fb6a9s ("ARM64 / ACPI: If we chose to boot from acpi then disable FDT"), let's not do DT hardware probing if ACPI is enabled in early boot. This avoids errors caused by repeated driver probing. Signed-off-by: Han Gao Link: https://lore.kernel.org/r/20250910112401.552987-1-rabenda.cn@gmail.com [pjw@kernel.org: cleaned up patch description and subject] Signed-off-by: Paul Walmsley Signed-off-by: Sasha Levin

RISC-V: clear hot-unplugged cores from all task mm_cpumasks to avoid rfence errors

2025-11-24T09:29:56+00:00

[ Upstream commit ae9e9f3d67dcef7582a4524047b01e33c5185ddb ] openSBI v1.7 adds harts checks for ipi operations. Especially it adds comparison between hmask passed as an argument from linux and mask of online harts (from openSBI side). If they don't fit each other the error occurs. When cpu is offline, cpu_online_mask is explicitly cleared in __cpu_disable. However, there is no explicit clearing of mm_cpumask. mm_cpumask is used for rfence operations that call openSBI RFENCE extension which uses ipi to remote harts. If hart is offline there may be error if mask of linux is not as mask of online harts in openSBI. this patch adds explicit clearing of mm_cpumask for offline hart. Signed-off-by: Danil Skrebenkov Reviewed-by: Andrew Jones Link: https://lore.kernel.org/r/20250919132849.31676-1-danil.skrebenkov@cloudbear.ru [pjw@kernel.org: rewrote subject line for clarity] Signed-off-by: Paul Walmsley Signed-off-by: Sasha Levin

riscv: stacktrace: fix backtracing through exceptions

2025-11-24T09:29:55+00:00

commit 51356ce60e5915a6bd812873186ed54e45c2699d upstream. Prior to commit 5d5fc33ce58e ("riscv: Improve exception and system call latency"), backtrace through exception worked since ra was filled with ret_from_exception symbol address and the stacktrace code checked 'pc' to be equal to that symbol. Now that handle_exception uses regular 'call' instructions, this isn't working anymore and backtrace stops at handle_exception(). Since there are multiple call site to C code in the exception handling path, rather than checking multiple potential return addresses, add a new symbol at the end of exception handling and check pc to be in that range. Fixes: 5d5fc33ce58e ("riscv: Improve exception and system call latency") Signed-off-by: Clément Léger Tested-by: Alexandre Ghiti Reviewed-by: Alexandre Ghiti Link: https://lore.kernel.org/r/20241209155714.1239665-1-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt Signed-off-by: Greg Kroah-Hartman

riscv: ptdump: use seq_puts() in pt_dump_seq_puts() macro

2025-11-24T09:29:50+00:00

[ Upstream commit a74f038fa50e0d33b740f44f862fe856f16de6a8 ] The pt_dump_seq_puts() macro incorrectly uses seq_printf() instead of seq_puts(). This is both a performance issue and conceptually wrong, as the macro name suggests plain string output (puts) but the implementation uses formatted output (printf). The macro is used in ptdump.c:301 to output a newline character. Using seq_printf() adds unnecessary overhead for format string parsing when outputting this constant string. This bug was introduced in commit 59c4da8640cc ("riscv: Add support to dump the kernel page tables") in 2020, which copied the implementation pattern from other architectures that had the same bug. Fixes: 59c4da8640cc ("riscv: Add support to dump the kernel page tables") Signed-off-by: Josephine Pfeiffer Link: https://lore.kernel.org/r/20251018170451.3355496-1-hi@josie.lol Signed-off-by: Paul Walmsley Signed-off-by: Sasha Levin

riscv: stacktrace: Disable KASAN checks for non-current tasks

2025-11-24T09:29:50+00:00

[ Upstream commit 060ea84a484e852b52b938f234bf9b5503a6c910 ] Unwinding the stack of a task other than current, KASAN would report "BUG: KASAN: out-of-bounds in walk_stackframe+0x41c/0x460" There is a same issue on x86 and has been resolved by the commit 84936118bdf3 ("x86/unwind: Disable KASAN checks for non-current tasks") The solution could be applied to RISC-V too. This patch also can solve the issue: https://seclists.org/oss-sec/2025/q4/23 Fixes: 5d8544e2d007 ("RISC-V: Generic library routines and assembly") Co-developed-by: Jiakai Xu Signed-off-by: Jiakai Xu Signed-off-by: Chunyan Zhang Link: https://lore.kernel.org/r/20251022072608.743484-1-zhangchunyan@iscas.ac.cn [pjw@kernel.org: clean up checkpatch issues] Signed-off-by: Paul Walmsley Signed-off-by: Sasha Levin