kernel/linux.git/arch/riscv, branch v5.10.257

riscv: kgdb: fix several debug register assignment bugs

2026-04-18T08:31:10+00:00

[ Upstream commit 834911eb8eef2501485d819b4eabebadc25c3497 ] Fix several bugs in the RISC-V kgdb implementation: - The element of dbg_reg_def[] that is supposed to pertain to the S1 register embeds instead the struct pt_regs offset of the A1 register. Fix this to use the S1 register offset in struct pt_regs. - The sleeping_thread_to_gdb_regs() function copies the value of the S10 register into the gdb_regs[] array element meant for the S9 register, and copies the value of the S11 register into the array element meant for the S10 register. It also neglects to copy the value of the S11 register. Fix all of these issues. Fixes: fe89bd2be8667 ("riscv: Add KGDB support") Cc: Vincent Chen Link: https://patch.msgid.link/fde376f8-bcfd-bfe4-e467-07d8f7608d05@kernel.org 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

2025-12-06T21:08:17+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: ptdump: use seq_puts() in pt_dump_seq_puts() macro

2025-12-06T21:08:16+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: Avoid fortify warning in syscall_get_arguments()

2025-05-02T05:41:02+00:00

commit adf53771a3123df99ca26e38818760fbcf5c05d0 upstream. When building with CONFIG_FORTIFY_SOURCE=y and W=1, there is a warning because of the memcpy() in syscall_get_arguments(): In file included from include/linux/string.h:392, from include/linux/bitmap.h:13, from include/linux/cpumask.h:12, from arch/riscv/include/asm/processor.h:55, from include/linux/sched.h:13, from kernel/ptrace.c:13: In function 'fortify_memcpy_chk', inlined from 'syscall_get_arguments.isra' at arch/riscv/include/asm/syscall.h:66:2: include/linux/fortify-string.h:580:25: error: call to '__read_overflow2_field' declared with attribute warning: detected read beyond size of field (2nd parameter); maybe use struct_group()? [-Werror=attribute-warning] 580 | __read_overflow2_field(q_size_field, size); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ cc1: all warnings being treated as errors The fortified memcpy() routine enforces that the source is not overread and the destination is not overwritten if the size of either field and the size of the copy are known at compile time. The memcpy() in syscall_get_arguments() intentionally overreads from a1 to a5 in 'struct pt_regs' but this is bigger than the size of a1. Normally, this could be solved by wrapping a1 through a5 with struct_group() but there was already a struct_group() applied to these members in commit bba547810c66 ("riscv: tracing: Fix __write_overflow_field in ftrace_partial_regs()"). Just avoid memcpy() altogether and write the copying of args from regs manually, which clears up the warning at the expense of three extra lines of code. Signed-off-by: Nathan Chancellor Reviewed-by: Dmitry V. Levin Fixes: e2c0cdfba7f6 ("RISC-V: User-facing API") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20250409-riscv-avoid-fortify-warning-syscall_get_arguments-v1-1-7853436d4755@kernel.org Signed-off-by: Palmer Dabbelt Signed-off-by: Greg Kroah-Hartman

riscv: KGDB: Remove ".option norvc/.option rvc" for kgdb_compiled_break

2025-05-02T05:41:00+00:00

[ Upstream commit 550c2aa787d1b06efcb11de1877354502a1237f2 ] [ Quoting Samuel Holland: ] This is a separate issue, but using ".option rvc" here is a bug. It will unconditionally enable the C extension for the rest of the file, even if the kernel is being built with CONFIG_RISCV_ISA_C=n. [ Quoting Palmer Dabbelt: ] We're just looking at the address of kgdb_compiled_break, so it's fine if it ends up as a c.ebreak. [ Quoting Alexandre Ghiti: ] .option norvc is used to prevent the assembler from using compressed instructions, but it's generally used when we need to ensure the size of the instructions that are used, which is not the case here as noted by Palmer since we only care about the address. So yes it will work fine with C enabled :) So let's just remove them all. Link: https://lore.kernel.org/all/4b4187c1-77e5-44b7-885f-d6826723dd9a@sifive.com/ Link: https://lore.kernel.org/all/mhng-69513841-5068-441d-be8f-2aeebdc56a08@palmer-ri-x1c9a/ Link: https://lore.kernel.org/all/23693e7f-4fff-40f3-a437-e06d827278a5@ghiti.fr/ Fixes: fe89bd2be866 ("riscv: Add KGDB support") Cc: Samuel Holland Cc: Palmer Dabbelt Cc: Alexandre Ghiti Signed-off-by: WangYuli Link: https://lore.kernel.org/r/8B431C6A4626225C+20250411073222.56820-2-wangyuli@uniontech.com Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin

riscv: KGDB: Do not inline arch_kgdb_breakpoint()

2025-05-02T05:41:00+00:00

[ Upstream commit 3af4bec9c1db3f003be4d5ae09b6a737e4be1612 ] The arch_kgdb_breakpoint() function defines the kgdb_compiled_break symbol using inline assembly. There's a potential issue where the compiler might inline arch_kgdb_breakpoint(), which would then define the kgdb_compiled_break symbol multiple times, leading to fail to link vmlinux.o. This isn't merely a potential compilation problem. The intent here is to determine the global symbol address of kgdb_compiled_break, and if this function is inlined multiple times, it would logically be a grave error. Link: https://lore.kernel.org/all/4b4187c1-77e5-44b7-885f-d6826723dd9a@sifive.com/ Link: https://lore.kernel.org/all/5b0adf9b-2b22-43fe-ab74-68df94115b9a@ghiti.fr/ Link: https://lore.kernel.org/all/23693e7f-4fff-40f3-a437-e06d827278a5@ghiti.fr/ Fixes: fe89bd2be866 ("riscv: Add KGDB support") Co-developed-by: Huacai Chen Signed-off-by: Huacai Chen Signed-off-by: WangYuli Link: https://lore.kernel.org/r/F22359AFB6FF9FD8+20250411073222.56820-1-wangyuli@uniontech.com Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin

riscv: Fix sleeping in invalid context in die()

2025-02-01T17:22:20+00:00

commit 6a97f4118ac07cfdc316433f385dbdc12af5025e upstream. die() can be called in exception handler, and therefore cannot sleep. However, die() takes spinlock_t which can sleep with PREEMPT_RT enabled. That causes the following warning: BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48 in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 285, name: mutex preempt_count: 110001, expected: 0 RCU nest depth: 0, expected: 0 CPU: 0 UID: 0 PID: 285 Comm: mutex Not tainted 6.12.0-rc7-00022-ge19049cf7d56-dirty #234 Hardware name: riscv-virtio,qemu (DT) Call Trace: dump_backtrace+0x1c/0x24 show_stack+0x2c/0x38 dump_stack_lvl+0x5a/0x72 dump_stack+0x14/0x1c __might_resched+0x130/0x13a rt_spin_lock+0x2a/0x5c die+0x24/0x112 do_trap_insn_illegal+0xa0/0xea _new_vmalloc_restore_context_a0+0xcc/0xd8 Oops - illegal instruction [#1] Switch to use raw_spinlock_t, which does not sleep even with PREEMPT_RT enabled. Fixes: 76d2a0493a17 ("RISC-V: Init and Halt Code") Signed-off-by: Nam Cao Cc: stable@vger.kernel.org Reviewed-by: Sebastian Andrzej Siewior Link: https://lore.kernel.org/r/20241118091333.1185288-1-namcao@linutronix.de Signed-off-by: Palmer Dabbelt Signed-off-by: Greg Kroah-Hartman

riscv: Remove duplicated GET_RM

2024-11-08T15:22:03+00:00

[ Upstream commit 164f66de6bb6ef454893f193c898dc8f1da6d18b ] The macro GET_RM defined twice in this file, one can be removed. Reviewed-by: Alexandre Ghiti Signed-off-by: Chunyan Zhang Fixes: 956d705dd279 ("riscv: Unaligned load/store handling for M_MODE") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20241008094141.549248-3-zhangchunyan@iscas.ac.cn Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin

riscv: Remove unused GENERATING_ASM_OFFSETS

2024-11-08T15:22:03+00:00

[ Upstream commit 46d4e5ac6f2f801f97bcd0ec82365969197dc9b1 ] The macro is not used in the current version of kernel, it looks like can be removed to avoid a build warning: ../arch/riscv/kernel/asm-offsets.c: At top level: ../arch/riscv/kernel/asm-offsets.c:7: warning: macro "GENERATING_ASM_OFFSETS" is not used [-Wunused-macros] 7 | #define GENERATING_ASM_OFFSETS Fixes: 9639a44394b9 ("RISC-V: Provide a cleaner raw_smp_processor_id()") Cc: stable@vger.kernel.org Reviewed-by: Alexandre Ghiti Tested-by: Alexandre Ghiti Signed-off-by: Chunyan Zhang Link: https://lore.kernel.org/r/20241008094141.549248-2-zhangchunyan@iscas.ac.cn Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin

riscv: Use '%u' to format the output of 'cpu'

2024-11-08T15:22:03+00:00

[ Upstream commit e0872ab72630dada3ae055bfa410bf463ff1d1e0 ] 'cpu' is an unsigned integer, so its conversion specifier should be %u, not %d. Suggested-by: Wentao Guan Suggested-by: Maciej W. Rozycki Link: https://lore.kernel.org/all/alpine.DEB.2.21.2409122309090.40372@angie.orcam.me.uk/ Signed-off-by: WangYuli Reviewed-by: Charlie Jenkins Tested-by: Charlie Jenkins Fixes: f1e58583b9c7 ("RISC-V: Support cpu hotplug") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/4C127DEECDA287C8+20241017032010.96772-1-wangyuli@uniontech.com Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin