diff options
Diffstat (limited to 'arch/x86/kernel')
-rw-r--r-- | arch/x86/kernel/cpu/bugs.c | 11 | ||||
-rw-r--r-- | arch/x86/kernel/perf_regs.c | 27 | ||||
-rw-r--r-- | arch/x86/kernel/process_32.c | 7 | ||||
-rw-r--r-- | arch/x86/kernel/process_64.c | 1 | ||||
-rw-r--r-- | arch/x86/kernel/setup.c | 6 | ||||
-rw-r--r-- | arch/x86/kernel/signal.c | 34 | ||||
-rw-r--r-- | arch/x86/kernel/stacktrace.c | 128 |
7 files changed, 77 insertions, 137 deletions
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index b91b3bfa5cfb..29630393f300 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -440,7 +440,8 @@ static enum spectre_v2_mitigation_cmd __init spectre_v2_parse_cmdline(void) char arg[20]; int ret, i; - if (cmdline_find_option_bool(boot_command_line, "nospectre_v2")) + if (cmdline_find_option_bool(boot_command_line, "nospectre_v2") || + cpu_mitigations_off()) return SPECTRE_V2_CMD_NONE; ret = cmdline_find_option(boot_command_line, "spectre_v2", arg, sizeof(arg)); @@ -672,7 +673,8 @@ static enum ssb_mitigation_cmd __init ssb_parse_cmdline(void) char arg[20]; int ret, i; - if (cmdline_find_option_bool(boot_command_line, "nospec_store_bypass_disable")) { + if (cmdline_find_option_bool(boot_command_line, "nospec_store_bypass_disable") || + cpu_mitigations_off()) { return SPEC_STORE_BYPASS_CMD_NONE; } else { ret = cmdline_find_option(boot_command_line, "spec_store_bypass_disable", @@ -1008,6 +1010,11 @@ static void __init l1tf_select_mitigation(void) if (!boot_cpu_has_bug(X86_BUG_L1TF)) return; + if (cpu_mitigations_off()) + l1tf_mitigation = L1TF_MITIGATION_OFF; + else if (cpu_mitigations_auto_nosmt()) + l1tf_mitigation = L1TF_MITIGATION_FLUSH_NOSMT; + override_cache_bits(&boot_cpu_data); switch (l1tf_mitigation) { diff --git a/arch/x86/kernel/perf_regs.c b/arch/x86/kernel/perf_regs.c index c06c4c16c6b6..07c30ee17425 100644 --- a/arch/x86/kernel/perf_regs.c +++ b/arch/x86/kernel/perf_regs.c @@ -59,18 +59,34 @@ static unsigned int pt_regs_offset[PERF_REG_X86_MAX] = { u64 perf_reg_value(struct pt_regs *regs, int idx) { + struct x86_perf_regs *perf_regs; + + if (idx >= PERF_REG_X86_XMM0 && idx < PERF_REG_X86_XMM_MAX) { + perf_regs = container_of(regs, struct x86_perf_regs, regs); + if (!perf_regs->xmm_regs) + return 0; + return perf_regs->xmm_regs[idx - PERF_REG_X86_XMM0]; + } + if (WARN_ON_ONCE(idx >= ARRAY_SIZE(pt_regs_offset))) return 0; return regs_get_register(regs, pt_regs_offset[idx]); } -#define REG_RESERVED (~((1ULL << PERF_REG_X86_MAX) - 1ULL)) - #ifdef CONFIG_X86_32 +#define REG_NOSUPPORT ((1ULL << PERF_REG_X86_R8) | \ + (1ULL << PERF_REG_X86_R9) | \ + (1ULL << PERF_REG_X86_R10) | \ + (1ULL << PERF_REG_X86_R11) | \ + (1ULL << PERF_REG_X86_R12) | \ + (1ULL << PERF_REG_X86_R13) | \ + (1ULL << PERF_REG_X86_R14) | \ + (1ULL << PERF_REG_X86_R15)) + int perf_reg_validate(u64 mask) { - if (!mask || mask & REG_RESERVED) + if (!mask || (mask & REG_NOSUPPORT)) return -EINVAL; return 0; @@ -96,10 +112,7 @@ void perf_get_regs_user(struct perf_regs *regs_user, int perf_reg_validate(u64 mask) { - if (!mask || mask & REG_RESERVED) - return -EINVAL; - - if (mask & REG_NOSUPPORT) + if (!mask || (mask & REG_NOSUPPORT)) return -EINVAL; return 0; diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index e471d8e6f0b2..70933193878c 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -127,6 +127,13 @@ int copy_thread_tls(unsigned long clone_flags, unsigned long sp, struct task_struct *tsk; int err; + /* + * For a new task use the RESET flags value since there is no before. + * All the status flags are zero; DF and all the system flags must also + * be 0, specifically IF must be 0 because we context switch to the new + * task with interrupts disabled. + */ + frame->flags = X86_EFLAGS_FIXED; frame->bp = 0; frame->ret_addr = (unsigned long) ret_from_fork; p->thread.sp = (unsigned long) fork_frame; diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 6a62f4af9fcf..844a28b29967 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -392,6 +392,7 @@ int copy_thread_tls(unsigned long clone_flags, unsigned long sp, childregs = task_pt_regs(p); fork_frame = container_of(childregs, struct fork_frame, regs); frame = &fork_frame->frame; + frame->bp = 0; frame->ret_addr = (unsigned long) ret_from_fork; p->thread.sp = (unsigned long) fork_frame; diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 3d872a527cd9..3773905cd2c1 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -1005,13 +1005,11 @@ void __init setup_arch(char **cmdline_p) if (efi_enabled(EFI_BOOT)) efi_init(); - dmi_scan_machine(); - dmi_memdev_walk(); - dmi_set_dump_stack_arch_desc(); + dmi_setup(); /* * VMware detection requires dmi to be available, so this - * needs to be done after dmi_scan_machine(), for the boot CPU. + * needs to be done after dmi_setup(), for the boot CPU. */ init_hypervisor_platform(); diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index 08dfd4c1a4f9..dff90fb6a9af 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -132,16 +132,6 @@ static int restore_sigcontext(struct pt_regs *regs, COPY_SEG_CPL3(cs); COPY_SEG_CPL3(ss); -#ifdef CONFIG_X86_64 - /* - * Fix up SS if needed for the benefit of old DOSEMU and - * CRIU. - */ - if (unlikely(!(uc_flags & UC_STRICT_RESTORE_SS) && - user_64bit_mode(regs))) - force_valid_ss(regs); -#endif - get_user_ex(tmpflags, &sc->flags); regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS); regs->orig_ax = -1; /* disable syscall checks */ @@ -150,6 +140,15 @@ static int restore_sigcontext(struct pt_regs *regs, buf = (void __user *)buf_val; } get_user_catch(err); +#ifdef CONFIG_X86_64 + /* + * Fix up SS if needed for the benefit of old DOSEMU and + * CRIU. + */ + if (unlikely(!(uc_flags & UC_STRICT_RESTORE_SS) && user_64bit_mode(regs))) + force_valid_ss(regs); +#endif + err |= fpu__restore_sig(buf, IS_ENABLED(CONFIG_X86_32)); force_iret(); @@ -461,6 +460,7 @@ static int __setup_rt_frame(int sig, struct ksignal *ksig, { struct rt_sigframe __user *frame; void __user *fp = NULL; + unsigned long uc_flags; int err = 0; frame = get_sigframe(&ksig->ka, regs, sizeof(struct rt_sigframe), &fp); @@ -473,9 +473,11 @@ static int __setup_rt_frame(int sig, struct ksignal *ksig, return -EFAULT; } + uc_flags = frame_uc_flags(regs); + put_user_try { /* Create the ucontext. */ - put_user_ex(frame_uc_flags(regs), &frame->uc.uc_flags); + put_user_ex(uc_flags, &frame->uc.uc_flags); put_user_ex(0, &frame->uc.uc_link); save_altstack_ex(&frame->uc.uc_stack, regs->sp); @@ -541,6 +543,7 @@ static int x32_setup_rt_frame(struct ksignal *ksig, { #ifdef CONFIG_X86_X32_ABI struct rt_sigframe_x32 __user *frame; + unsigned long uc_flags; void __user *restorer; int err = 0; void __user *fpstate = NULL; @@ -555,9 +558,11 @@ static int x32_setup_rt_frame(struct ksignal *ksig, return -EFAULT; } + uc_flags = frame_uc_flags(regs); + put_user_try { /* Create the ucontext. */ - put_user_ex(frame_uc_flags(regs), &frame->uc.uc_flags); + put_user_ex(uc_flags, &frame->uc.uc_flags); put_user_ex(0, &frame->uc.uc_link); compat_save_altstack_ex(&frame->uc.uc_stack, regs->sp); put_user_ex(0, &frame->uc.uc__pad0); @@ -688,10 +693,7 @@ setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs) sigset_t *set = sigmask_to_save(); compat_sigset_t *cset = (compat_sigset_t *) set; - /* - * Increment event counter and perform fixup for the pre-signal - * frame. - */ + /* Perform fixup for the pre-signal frame. */ rseq_signal_deliver(ksig, regs); /* Set up the stack frame */ diff --git a/arch/x86/kernel/stacktrace.c b/arch/x86/kernel/stacktrace.c index 5c2d71a1dc06..2abf27d7df6b 100644 --- a/arch/x86/kernel/stacktrace.c +++ b/arch/x86/kernel/stacktrace.c @@ -12,78 +12,31 @@ #include <asm/stacktrace.h> #include <asm/unwind.h> -static int save_stack_address(struct stack_trace *trace, unsigned long addr, - bool nosched) -{ - if (nosched && in_sched_functions(addr)) - return 0; - - if (trace->skip > 0) { - trace->skip--; - return 0; - } - - if (trace->nr_entries >= trace->max_entries) - return -1; - - trace->entries[trace->nr_entries++] = addr; - return 0; -} - -static void noinline __save_stack_trace(struct stack_trace *trace, - struct task_struct *task, struct pt_regs *regs, - bool nosched) +void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie, + struct task_struct *task, struct pt_regs *regs) { struct unwind_state state; unsigned long addr; - if (regs) - save_stack_address(trace, regs->ip, nosched); + if (regs && !consume_entry(cookie, regs->ip, false)) + return; for (unwind_start(&state, task, regs, NULL); !unwind_done(&state); unwind_next_frame(&state)) { addr = unwind_get_return_address(&state); - if (!addr || save_stack_address(trace, addr, nosched)) + if (!addr || !consume_entry(cookie, addr, false)) break; } - - if (trace->nr_entries < trace->max_entries) - trace->entries[trace->nr_entries++] = ULONG_MAX; } /* - * Save stack-backtrace addresses into a stack_trace buffer. + * This function returns an error if it detects any unreliable features of the + * stack. Otherwise it guarantees that the stack trace is reliable. + * + * If the task is not 'current', the caller *must* ensure the task is inactive. */ -void save_stack_trace(struct stack_trace *trace) -{ - trace->skip++; - __save_stack_trace(trace, current, NULL, false); -} -EXPORT_SYMBOL_GPL(save_stack_trace); - -void save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace) -{ - __save_stack_trace(trace, current, regs, false); -} - -void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) -{ - if (!try_get_task_stack(tsk)) - return; - - if (tsk == current) - trace->skip++; - __save_stack_trace(trace, tsk, NULL, true); - - put_task_stack(tsk); -} -EXPORT_SYMBOL_GPL(save_stack_trace_tsk); - -#ifdef CONFIG_HAVE_RELIABLE_STACKTRACE - -static int __always_inline -__save_stack_trace_reliable(struct stack_trace *trace, - struct task_struct *task) +int arch_stack_walk_reliable(stack_trace_consume_fn consume_entry, + void *cookie, struct task_struct *task) { struct unwind_state state; struct pt_regs *regs; @@ -97,7 +50,7 @@ __save_stack_trace_reliable(struct stack_trace *trace, if (regs) { /* Success path for user tasks */ if (user_mode(regs)) - goto success; + return 0; /* * Kernel mode registers on the stack indicate an @@ -120,7 +73,7 @@ __save_stack_trace_reliable(struct stack_trace *trace, if (!addr) return -EINVAL; - if (save_stack_address(trace, addr, false)) + if (!consume_entry(cookie, addr, false)) return -EINVAL; } @@ -132,39 +85,9 @@ __save_stack_trace_reliable(struct stack_trace *trace, if (!(task->flags & (PF_KTHREAD | PF_IDLE))) return -EINVAL; -success: - if (trace->nr_entries < trace->max_entries) - trace->entries[trace->nr_entries++] = ULONG_MAX; - return 0; } -/* - * This function returns an error if it detects any unreliable features of the - * stack. Otherwise it guarantees that the stack trace is reliable. - * - * If the task is not 'current', the caller *must* ensure the task is inactive. - */ -int save_stack_trace_tsk_reliable(struct task_struct *tsk, - struct stack_trace *trace) -{ - int ret; - - /* - * If the task doesn't have a stack (e.g., a zombie), the stack is - * "reliably" empty. - */ - if (!try_get_task_stack(tsk)) - return 0; - - ret = __save_stack_trace_reliable(trace, tsk); - - put_task_stack(tsk); - - return ret; -} -#endif /* CONFIG_HAVE_RELIABLE_STACKTRACE */ - /* Userspace stacktrace - based on kernel/trace/trace_sysprof.c */ struct stack_frame_user { @@ -189,15 +112,15 @@ copy_stack_frame(const void __user *fp, struct stack_frame_user *frame) return ret; } -static inline void __save_stack_trace_user(struct stack_trace *trace) +void arch_stack_walk_user(stack_trace_consume_fn consume_entry, void *cookie, + const struct pt_regs *regs) { - const struct pt_regs *regs = task_pt_regs(current); const void __user *fp = (const void __user *)regs->bp; - if (trace->nr_entries < trace->max_entries) - trace->entries[trace->nr_entries++] = regs->ip; + if (!consume_entry(cookie, regs->ip, false)) + return; - while (trace->nr_entries < trace->max_entries) { + while (1) { struct stack_frame_user frame; frame.next_fp = NULL; @@ -207,8 +130,8 @@ static inline void __save_stack_trace_user(struct stack_trace *trace) if ((unsigned long)fp < regs->sp) break; if (frame.ret_addr) { - trace->entries[trace->nr_entries++] = - frame.ret_addr; + if (!consume_entry(cookie, frame.ret_addr, false)) + return; } if (fp == frame.next_fp) break; @@ -216,14 +139,3 @@ static inline void __save_stack_trace_user(struct stack_trace *trace) } } -void save_stack_trace_user(struct stack_trace *trace) -{ - /* - * Trace user stack if we are not a kernel thread - */ - if (current->mm) { - __save_stack_trace_user(trace); - } - if (trace->nr_entries < trace->max_entries) - trace->entries[trace->nr_entries++] = ULONG_MAX; -} |