diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2023-02-03 10:18:39 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2023-02-03 10:18:39 -0800 |
commit | a30df1ea94ad35c7b42d44199fe1376b4d648862 (patch) | |
tree | 5188b188878cd8898bdc14a05be18d50b3941bbe | |
parent | bffede38f82c27cf5e203a2c659fcc9b581dd7b8 (diff) | |
parent | 2f394c0e7d1129a35156e492bc8f445fb20f43ac (diff) |
Merge tag 'riscv-for-linus-6.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V fixes from Palmer Dabbelt:
- A build fix to avoid static branches in cpu_relax(), which greatly
inflates the jump tables and breaks at least
CONFIG_CC_OPTIMIZE_FOR_SIZE=y.
- A fix for a kernel panic when probing impossible instruction
positions.
- A fix to disable unwind tables, which are enabled by default for
GCC-13 and result in unhandled relocations in modules.
* tag 'riscv-for-linus-6.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: disable generation of unwind tables
riscv: kprobe: Fixup kernel panic when probing an illegal position
riscv: Fix build with CONFIG_CC_OPTIMIZE_FOR_SIZE=y
-rw-r--r-- | arch/riscv/Makefile | 3 | ||||
-rw-r--r-- | arch/riscv/include/asm/hwcap.h | 3 | ||||
-rw-r--r-- | arch/riscv/include/asm/vdso/processor.h | 28 | ||||
-rw-r--r-- | arch/riscv/kernel/probes/kprobes.c | 18 |
4 files changed, 33 insertions, 19 deletions
diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile index faf2c2177094..82153960ac00 100644 --- a/arch/riscv/Makefile +++ b/arch/riscv/Makefile @@ -80,6 +80,9 @@ ifeq ($(CONFIG_PERF_EVENTS),y) KBUILD_CFLAGS += -fno-omit-frame-pointer endif +# Avoid generating .eh_frame sections. +KBUILD_CFLAGS += -fno-asynchronous-unwind-tables -fno-unwind-tables + KBUILD_CFLAGS_MODULE += $(call cc-option,-mno-relax) KBUILD_AFLAGS_MODULE += $(call as-option,-Wa$(comma)-mno-relax) diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h index 86328e3acb02..64ad1937e714 100644 --- a/arch/riscv/include/asm/hwcap.h +++ b/arch/riscv/include/asm/hwcap.h @@ -70,7 +70,6 @@ static_assert(RISCV_ISA_EXT_ID_MAX <= RISCV_ISA_EXT_MAX); */ enum riscv_isa_ext_key { RISCV_ISA_EXT_KEY_FPU, /* For 'F' and 'D' */ - RISCV_ISA_EXT_KEY_ZIHINTPAUSE, RISCV_ISA_EXT_KEY_SVINVAL, RISCV_ISA_EXT_KEY_MAX, }; @@ -91,8 +90,6 @@ static __always_inline int riscv_isa_ext2key(int num) return RISCV_ISA_EXT_KEY_FPU; case RISCV_ISA_EXT_d: return RISCV_ISA_EXT_KEY_FPU; - case RISCV_ISA_EXT_ZIHINTPAUSE: - return RISCV_ISA_EXT_KEY_ZIHINTPAUSE; case RISCV_ISA_EXT_SVINVAL: return RISCV_ISA_EXT_KEY_SVINVAL; default: diff --git a/arch/riscv/include/asm/vdso/processor.h b/arch/riscv/include/asm/vdso/processor.h index fa70cfe507aa..14f5d27783b8 100644 --- a/arch/riscv/include/asm/vdso/processor.h +++ b/arch/riscv/include/asm/vdso/processor.h @@ -4,30 +4,26 @@ #ifndef __ASSEMBLY__ -#include <linux/jump_label.h> #include <asm/barrier.h> -#include <asm/hwcap.h> static inline void cpu_relax(void) { - if (!static_branch_likely(&riscv_isa_ext_keys[RISCV_ISA_EXT_KEY_ZIHINTPAUSE])) { #ifdef __riscv_muldiv - int dummy; - /* In lieu of a halt instruction, induce a long-latency stall. */ - __asm__ __volatile__ ("div %0, %0, zero" : "=r" (dummy)); + int dummy; + /* In lieu of a halt instruction, induce a long-latency stall. */ + __asm__ __volatile__ ("div %0, %0, zero" : "=r" (dummy)); #endif - } else { - /* - * Reduce instruction retirement. - * This assumes the PC changes. - */ -#ifdef CONFIG_TOOLCHAIN_HAS_ZIHINTPAUSE - __asm__ __volatile__ ("pause"); + +#ifdef __riscv_zihintpause + /* + * Reduce instruction retirement. + * This assumes the PC changes. + */ + __asm__ __volatile__ ("pause"); #else - /* Encoding of the pause instruction */ - __asm__ __volatile__ (".4byte 0x100000F"); + /* Encoding of the pause instruction */ + __asm__ __volatile__ (".4byte 0x100000F"); #endif - } barrier(); } diff --git a/arch/riscv/kernel/probes/kprobes.c b/arch/riscv/kernel/probes/kprobes.c index f21592d20306..41c7481afde3 100644 --- a/arch/riscv/kernel/probes/kprobes.c +++ b/arch/riscv/kernel/probes/kprobes.c @@ -48,6 +48,21 @@ static void __kprobes arch_simulate_insn(struct kprobe *p, struct pt_regs *regs) post_kprobe_handler(p, kcb, regs); } +static bool __kprobes arch_check_kprobe(struct kprobe *p) +{ + unsigned long tmp = (unsigned long)p->addr - p->offset; + unsigned long addr = (unsigned long)p->addr; + + while (tmp <= addr) { + if (tmp == addr) + return true; + + tmp += GET_INSN_LENGTH(*(u16 *)tmp); + } + + return false; +} + int __kprobes arch_prepare_kprobe(struct kprobe *p) { unsigned long probe_addr = (unsigned long)p->addr; @@ -55,6 +70,9 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) if (probe_addr & 0x1) return -EILSEQ; + if (!arch_check_kprobe(p)) + return -EILSEQ; + /* copy instruction */ p->opcode = *p->addr; |