diff options
Diffstat (limited to 'arch/x86/kernel')
-rw-r--r-- | arch/x86/kernel/cpu/common.c | 5 | ||||
-rw-r--r-- | arch/x86/kernel/entry_32.S | 19 | ||||
-rw-r--r-- | arch/x86/kernel/i387.c | 107 | ||||
-rw-r--r-- | arch/x86/kernel/irqinit.c | 2 | ||||
-rw-r--r-- | arch/x86/kernel/process.c | 20 | ||||
-rw-r--r-- | arch/x86/kernel/process_32.c | 2 | ||||
-rw-r--r-- | arch/x86/kernel/process_64.c | 2 | ||||
-rw-r--r-- | arch/x86/kernel/traps.c | 173 | ||||
-rw-r--r-- | arch/x86/kernel/xsave.c | 8 |
9 files changed, 136 insertions, 202 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 4868e4a951ee..c1c00d0b1692 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1243,10 +1243,7 @@ void __cpuinit cpu_init(void) /* * Force FPU initialization: */ - if (cpu_has_xsave) - current_thread_info()->status = TS_XSAVE; - else - current_thread_info()->status = 0; + current_thread_info()->status = 0; clear_used_math(); mxcsr_feature_mask_init(); diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S index 44a8e0dc6737..cd49141cf153 100644 --- a/arch/x86/kernel/entry_32.S +++ b/arch/x86/kernel/entry_32.S @@ -53,6 +53,7 @@ #include <asm/processor-flags.h> #include <asm/ftrace.h> #include <asm/irq_vectors.h> +#include <asm/cpufeature.h> /* Avoid __ASSEMBLER__'ifying <linux/audit.h> just for this. */ #include <linux/elf-em.h> @@ -905,7 +906,25 @@ ENTRY(simd_coprocessor_error) RING0_INT_FRAME pushl $0 CFI_ADJUST_CFA_OFFSET 4 +#ifdef CONFIG_X86_INVD_BUG + /* AMD 486 bug: invd from userspace calls exception 19 instead of #GP */ +661: pushl $do_general_protection +662: +.section .altinstructions,"a" + .balign 4 + .long 661b + .long 663f + .byte X86_FEATURE_XMM + .byte 662b-661b + .byte 664f-663f +.previous +.section .altinstr_replacement,"ax" +663: pushl $do_simd_coprocessor_error +664: +.previous +#else pushl $do_simd_coprocessor_error +#endif CFI_ADJUST_CFA_OFFSET 4 jmp error_code CFI_ENDPROC diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c index 54c31c285488..86cef6b32253 100644 --- a/arch/x86/kernel/i387.c +++ b/arch/x86/kernel/i387.c @@ -102,65 +102,62 @@ void __cpuinit fpu_init(void) mxcsr_feature_mask_init(); /* clean state in init */ - if (cpu_has_xsave) - current_thread_info()->status = TS_XSAVE; - else - current_thread_info()->status = 0; + current_thread_info()->status = 0; clear_used_math(); } #endif /* CONFIG_X86_64 */ -/* - * The _current_ task is using the FPU for the first time - * so initialize it and set the mxcsr to its default - * value at reset if we support XMM instructions and then - * remeber the current task has used the FPU. - */ -int init_fpu(struct task_struct *tsk) +static void fpu_finit(struct fpu *fpu) { - if (tsk_used_math(tsk)) { - if (HAVE_HWFP && tsk == current) - unlazy_fpu(tsk); - return 0; - } - - /* - * Memory allocation at the first usage of the FPU and other state. - */ - if (!tsk->thread.xstate) { - tsk->thread.xstate = kmem_cache_alloc(task_xstate_cachep, - GFP_KERNEL); - if (!tsk->thread.xstate) - return -ENOMEM; - } - #ifdef CONFIG_X86_32 if (!HAVE_HWFP) { - memset(tsk->thread.xstate, 0, xstate_size); - finit_task(tsk); - set_stopped_child_used_math(tsk); - return 0; + finit_soft_fpu(&fpu->state->soft); + return; } #endif if (cpu_has_fxsr) { - struct i387_fxsave_struct *fx = &tsk->thread.xstate->fxsave; + struct i387_fxsave_struct *fx = &fpu->state->fxsave; memset(fx, 0, xstate_size); fx->cwd = 0x37f; if (cpu_has_xmm) fx->mxcsr = MXCSR_DEFAULT; } else { - struct i387_fsave_struct *fp = &tsk->thread.xstate->fsave; + struct i387_fsave_struct *fp = &fpu->state->fsave; memset(fp, 0, xstate_size); fp->cwd = 0xffff037fu; fp->swd = 0xffff0000u; fp->twd = 0xffffffffu; fp->fos = 0xffff0000u; } +} + +/* + * The _current_ task is using the FPU for the first time + * so initialize it and set the mxcsr to its default + * value at reset if we support XMM instructions and then + * remeber the current task has used the FPU. + */ +int init_fpu(struct task_struct *tsk) +{ + int ret; + + if (tsk_used_math(tsk)) { + if (HAVE_HWFP && tsk == current) + unlazy_fpu(tsk); + return 0; + } + /* - * Only the device not available exception or ptrace can call init_fpu. + * Memory allocation at the first usage of the FPU and other state. */ + ret = fpu_alloc(&tsk->thread.fpu); + if (ret) + return ret; + + fpu_finit(&tsk->thread.fpu); + set_stopped_child_used_math(tsk); return 0; } @@ -194,7 +191,7 @@ int xfpregs_get(struct task_struct *target, const struct user_regset *regset, return ret; return user_regset_copyout(&pos, &count, &kbuf, &ubuf, - &target->thread.xstate->fxsave, 0, -1); + &target->thread.fpu.state->fxsave, 0, -1); } int xfpregs_set(struct task_struct *target, const struct user_regset *regset, @@ -211,19 +208,19 @@ int xfpregs_set(struct task_struct *target, const struct user_regset *regset, return ret; ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, - &target->thread.xstate->fxsave, 0, -1); + &target->thread.fpu.state->fxsave, 0, -1); /* * mxcsr reserved bits must be masked to zero for security reasons. */ - target->thread.xstate->fxsave.mxcsr &= mxcsr_feature_mask; + target->thread.fpu.state->fxsave.mxcsr &= mxcsr_feature_mask; /* * update the header bits in the xsave header, indicating the * presence of FP and SSE state. */ if (cpu_has_xsave) - target->thread.xstate->xsave.xsave_hdr.xstate_bv |= XSTATE_FPSSE; + target->thread.fpu.state->xsave.xsave_hdr.xstate_bv |= XSTATE_FPSSE; return ret; } @@ -246,14 +243,14 @@ int xstateregs_get(struct task_struct *target, const struct user_regset *regset, * memory layout in the thread struct, so that we can copy the entire * xstateregs to the user using one user_regset_copyout(). */ - memcpy(&target->thread.xstate->fxsave.sw_reserved, + memcpy(&target->thread.fpu.state->fxsave.sw_reserved, xstate_fx_sw_bytes, sizeof(xstate_fx_sw_bytes)); /* * Copy the xstate memory layout. */ ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, - &target->thread.xstate->xsave, 0, -1); + &target->thread.fpu.state->xsave, 0, -1); return ret; } @@ -272,14 +269,14 @@ int xstateregs_set(struct task_struct *target, const struct user_regset *regset, return ret; ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, - &target->thread.xstate->xsave, 0, -1); + &target->thread.fpu.state->xsave, 0, -1); /* * mxcsr reserved bits must be masked to zero for security reasons. */ - target->thread.xstate->fxsave.mxcsr &= mxcsr_feature_mask; + target->thread.fpu.state->fxsave.mxcsr &= mxcsr_feature_mask; - xsave_hdr = &target->thread.xstate->xsave.xsave_hdr; + xsave_hdr = &target->thread.fpu.state->xsave.xsave_hdr; xsave_hdr->xstate_bv &= pcntxt_mask; /* @@ -365,7 +362,7 @@ static inline u32 twd_fxsr_to_i387(struct i387_fxsave_struct *fxsave) static void convert_from_fxsr(struct user_i387_ia32_struct *env, struct task_struct *tsk) { - struct i387_fxsave_struct *fxsave = &tsk->thread.xstate->fxsave; + struct i387_fxsave_struct *fxsave = &tsk->thread.fpu.state->fxsave; struct _fpreg *to = (struct _fpreg *) &env->st_space[0]; struct _fpxreg *from = (struct _fpxreg *) &fxsave->st_space[0]; int i; @@ -405,7 +402,7 @@ static void convert_to_fxsr(struct task_struct *tsk, const struct user_i387_ia32_struct *env) { - struct i387_fxsave_struct *fxsave = &tsk->thread.xstate->fxsave; + struct i387_fxsave_struct *fxsave = &tsk->thread.fpu.state->fxsave; struct _fpreg *from = (struct _fpreg *) &env->st_space[0]; struct _fpxreg *to = (struct _fpxreg *) &fxsave->st_space[0]; int i; @@ -445,7 +442,7 @@ int fpregs_get(struct task_struct *target, const struct user_regset *regset, if (!cpu_has_fxsr) { return user_regset_copyout(&pos, &count, &kbuf, &ubuf, - &target->thread.xstate->fsave, 0, + &target->thread.fpu.state->fsave, 0, -1); } @@ -475,7 +472,7 @@ int fpregs_set(struct task_struct *target, const struct user_regset *regset, if (!cpu_has_fxsr) { return user_regset_copyin(&pos, &count, &kbuf, &ubuf, - &target->thread.xstate->fsave, 0, -1); + &target->thread.fpu.state->fsave, 0, -1); } if (pos > 0 || count < sizeof(env)) @@ -490,7 +487,7 @@ int fpregs_set(struct task_struct *target, const struct user_regset *regset, * presence of FP. */ if (cpu_has_xsave) - target->thread.xstate->xsave.xsave_hdr.xstate_bv |= XSTATE_FP; + target->thread.fpu.state->xsave.xsave_hdr.xstate_bv |= XSTATE_FP; return ret; } @@ -501,7 +498,7 @@ int fpregs_set(struct task_struct *target, const struct user_regset *regset, static inline int save_i387_fsave(struct _fpstate_ia32 __user *buf) { struct task_struct *tsk = current; - struct i387_fsave_struct *fp = &tsk->thread.xstate->fsave; + struct i387_fsave_struct *fp = &tsk->thread.fpu.state->fsave; fp->status = fp->swd; if (__copy_to_user(buf, fp, sizeof(struct i387_fsave_struct))) @@ -512,7 +509,7 @@ static inline int save_i387_fsave(struct _fpstate_ia32 __user *buf) static int save_i387_fxsave(struct _fpstate_ia32 __user *buf) { struct task_struct *tsk = current; - struct i387_fxsave_struct *fx = &tsk->thread.xstate->fxsave; + struct i387_fxsave_struct *fx = &tsk->thread.fpu.state->fxsave; struct user_i387_ia32_struct env; int err = 0; @@ -547,7 +544,7 @@ static int save_i387_xsave(void __user *buf) * header as well as change any contents in the memory layout. * xrestore as part of sigreturn will capture all the changes. */ - tsk->thread.xstate->xsave.xsave_hdr.xstate_bv |= XSTATE_FPSSE; + tsk->thread.fpu.state->xsave.xsave_hdr.xstate_bv |= XSTATE_FPSSE; if (save_i387_fxsave(fx) < 0) return -1; @@ -599,7 +596,7 @@ static inline int restore_i387_fsave(struct _fpstate_ia32 __user *buf) { struct task_struct *tsk = current; - return __copy_from_user(&tsk->thread.xstate->fsave, buf, + return __copy_from_user(&tsk->thread.fpu.state->fsave, buf, sizeof(struct i387_fsave_struct)); } @@ -610,10 +607,10 @@ static int restore_i387_fxsave(struct _fpstate_ia32 __user *buf, struct user_i387_ia32_struct env; int err; - err = __copy_from_user(&tsk->thread.xstate->fxsave, &buf->_fxsr_env[0], + err = __copy_from_user(&tsk->thread.fpu.state->fxsave, &buf->_fxsr_env[0], size); /* mxcsr reserved bits must be masked to zero for security reasons */ - tsk->thread.xstate->fxsave.mxcsr &= mxcsr_feature_mask; + tsk->thread.fpu.state->fxsave.mxcsr &= mxcsr_feature_mask; if (err || __copy_from_user(&env, buf, sizeof(env))) return 1; convert_to_fxsr(tsk, &env); @@ -629,7 +626,7 @@ static int restore_i387_xsave(void __user *buf) struct i387_fxsave_struct __user *fx = (struct i387_fxsave_struct __user *) &fx_user->_fxsr_env[0]; struct xsave_hdr_struct *xsave_hdr = - ¤t->thread.xstate->xsave.xsave_hdr; + ¤t->thread.fpu.state->xsave.xsave_hdr; u64 mask; int err; diff --git a/arch/x86/kernel/irqinit.c b/arch/x86/kernel/irqinit.c index 0ed2d300cd46..990ae7cfc578 100644 --- a/arch/x86/kernel/irqinit.c +++ b/arch/x86/kernel/irqinit.c @@ -60,7 +60,7 @@ static irqreturn_t math_error_irq(int cpl, void *dev_id) outb(0, 0xF0); if (ignore_fpu_irq || !boot_cpu_data.hard_math) return IRQ_NONE; - math_error((void __user *)get_irq_regs()->ip); + math_error(get_irq_regs(), 0, 16); return IRQ_HANDLED; } diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index cc6877535ef4..e7e35219b32f 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -31,24 +31,22 @@ struct kmem_cache *task_xstate_cachep; int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src) { + int ret; + *dst = *src; - if (src->thread.xstate) { - dst->thread.xstate = kmem_cache_alloc(task_xstate_cachep, - GFP_KERNEL); - if (!dst->thread.xstate) - return -ENOMEM; - WARN_ON((unsigned long)dst->thread.xstate & 15); - memcpy(dst->thread.xstate, src->thread.xstate, xstate_size); + if (fpu_allocated(&src->thread.fpu)) { + memset(&dst->thread.fpu, 0, sizeof(dst->thread.fpu)); + ret = fpu_alloc(&dst->thread.fpu); + if (ret) + return ret; + fpu_copy(&dst->thread.fpu, &src->thread.fpu); } return 0; } void free_thread_xstate(struct task_struct *tsk) { - if (tsk->thread.xstate) { - kmem_cache_free(task_xstate_cachep, tsk->thread.xstate); - tsk->thread.xstate = NULL; - } + fpu_free(&tsk->thread.fpu); } void free_thread_info(struct thread_info *ti) diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index 75090c589b7a..8d128783af47 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -309,7 +309,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) /* we're going to use this soon, after a few expensive things */ if (preload_fpu) - prefetch(next->xstate); + prefetch(next->fpu.state); /* * Reload esp0. diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 50cc84ac0a0d..3c2422a99f1f 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -388,7 +388,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) /* we're going to use this soon, after a few expensive things */ if (preload_fpu) - prefetch(next->xstate); + prefetch(next->fpu.state); /* * Reload esp0, LDT and the page table pointer: diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 36f1bd9f8e76..02cfb9b8f5b1 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -108,15 +108,6 @@ static inline void preempt_conditional_cli(struct pt_regs *regs) dec_preempt_count(); } -#ifdef CONFIG_X86_32 -static inline void -die_if_kernel(const char *str, struct pt_regs *regs, long err) -{ - if (!user_mode_vm(regs)) - die(str, regs, err); -} -#endif - static void __kprobes do_trap(int trapnr, int signr, char *str, struct pt_regs *regs, long error_code, siginfo_t *info) @@ -585,55 +576,67 @@ dotraplinkage void __kprobes do_debug(struct pt_regs *regs, long error_code) return; } -#ifdef CONFIG_X86_64 -static int kernel_math_error(struct pt_regs *regs, const char *str, int trapnr) -{ - if (fixup_exception(regs)) - return 1; - - notify_die(DIE_GPF, str, regs, 0, trapnr, SIGFPE); - /* Illegal floating point operation in the kernel */ - current->thread.trap_no = trapnr; - die(str, regs, 0); - return 0; -} -#endif - /* * Note that we play around with the 'TS' bit in an attempt to get * the correct behaviour even in the presence of the asynchronous * IRQ13 behaviour */ -void math_error(void __user *ip) +void math_error(struct pt_regs *regs, int error_code, int trapnr) { - struct task_struct *task; + struct task_struct *task = current; siginfo_t info; - unsigned short cwd, swd, err; + unsigned short err; + char *str = (trapnr == 16) ? "fpu exception" : "simd exception"; + + if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, SIGFPE) == NOTIFY_STOP) + return; + conditional_sti(regs); + + if (!user_mode_vm(regs)) + { + if (!fixup_exception(regs)) { + task->thread.error_code = error_code; + task->thread.trap_no = trapnr; + die(str, regs, error_code); + } + return; + } /* * Save the info for the exception handler and clear the error. */ - task = current; save_init_fpu(task); - task->thread.trap_no = 16; - task->thread.error_code = 0; + task->thread.trap_no = trapnr; + task->thread.error_code = error_code; info.si_signo = SIGFPE; info.si_errno = 0; - info.si_addr = ip; - /* - * (~cwd & swd) will mask out exceptions that are not set to unmasked - * status. 0x3f is the exception bits in these regs, 0x200 is the - * C1 reg you need in case of a stack fault, 0x040 is the stack - * fault bit. We should only be taking one exception at a time, - * so if this combination doesn't produce any single exception, - * then we have a bad program that isn't synchronizing its FPU usage - * and it will suffer the consequences since we won't be able to - * fully reproduce the context of the exception - */ - cwd = get_fpu_cwd(task); - swd = get_fpu_swd(task); + info.si_addr = (void __user *)regs->ip; + if (trapnr == 16) { + unsigned short cwd, swd; + /* + * (~cwd & swd) will mask out exceptions that are not set to unmasked + * status. 0x3f is the exception bits in these regs, 0x200 is the + * C1 reg you need in case of a stack fault, 0x040 is the stack + * fault bit. We should only be taking one exception at a time, + * so if this combination doesn't produce any single exception, + * then we have a bad program that isn't synchronizing its FPU usage + * and it will suffer the consequences since we won't be able to + * fully reproduce the context of the exception + */ + cwd = get_fpu_cwd(task); + swd = get_fpu_swd(task); - err = swd & ~cwd; + err = swd & ~cwd; + } else { + /* + * The SIMD FPU exceptions are handled a little differently, as there + * is only a single status/control register. Thus, to determine which + * unmasked exception was caught we must mask the exception mask bits + * at 0x1f80, and then use these to mask the exception bits at 0x3f. + */ + unsigned short mxcsr = get_fpu_mxcsr(task); + err = ~(mxcsr >> 7) & mxcsr; + } if (err & 0x001) { /* Invalid op */ /* @@ -662,97 +665,17 @@ void math_error(void __user *ip) dotraplinkage void do_coprocessor_error(struct pt_regs *regs, long error_code) { - conditional_sti(regs); - #ifdef CONFIG_X86_32 ignore_fpu_irq = 1; -#else - if (!user_mode(regs) && - kernel_math_error(regs, "kernel x87 math error", 16)) - return; #endif - math_error((void __user *)regs->ip); -} - -static void simd_math_error(void __user *ip) -{ - struct task_struct *task; - siginfo_t info; - unsigned short mxcsr; - - /* - * Save the info for the exception handler and clear the error. - */ - task = current; - save_init_fpu(task); - task->thread.trap_no = 19; - task->thread.error_code = 0; - info.si_signo = SIGFPE; - info.si_errno = 0; - info.si_code = __SI_FAULT; - info.si_addr = ip; - /* - * The SIMD FPU exceptions are handled a little differently, as there - * is only a single status/control register. Thus, to determine which - * unmasked exception was caught we must mask the exception mask bits - * at 0x1f80, and then use these to mask the exception bits at 0x3f. - */ - mxcsr = get_fpu_mxcsr(task); - switch (~((mxcsr & 0x1f80) >> 7) & (mxcsr & 0x3f)) { - case 0x000: - default: - break; - case 0x001: /* Invalid Op */ - info.si_code = FPE_FLTINV; - break; - case 0x002: /* Denormalize */ - case 0x010: /* Underflow */ - info.si_code = FPE_FLTUND; - break; - case 0x004: /* Zero Divide */ - info.si_code = FPE_FLTDIV; - break; - case 0x008: /* Overflow */ - info.si_code = FPE_FLTOVF; - break; - case 0x020: /* Precision */ - info.si_code = FPE_FLTRES; - break; - } - force_sig_info(SIGFPE, &info, task); + math_error(regs, error_code, 16); } dotraplinkage void do_simd_coprocessor_error(struct pt_regs *regs, long error_code) { - conditional_sti(regs); - -#ifdef CONFIG_X86_32 - if (cpu_has_xmm) { - /* Handle SIMD FPU exceptions on PIII+ processors. */ - ignore_fpu_irq = 1; - simd_math_error((void __user *)regs->ip); - return; - } - /* - * Handle strange cache flush from user space exception - * in all other cases. This is undocumented behaviour. - */ - if (regs->flags & X86_VM_MASK) { - handle_vm86_fault((struct kernel_vm86_regs *)regs, error_code); - return; - } - current->thread.trap_no = 19; - current->thread.error_code = error_code; - die_if_kernel("cache flush denied", regs, error_code); - force_sig(SIGSEGV, current); -#else - if (!user_mode(regs) && - kernel_math_error(regs, "kernel simd math error", 19)) - return; - simd_math_error((void __user *)regs->ip); -#endif + math_error(regs, error_code, 19); } dotraplinkage void diff --git a/arch/x86/kernel/xsave.c b/arch/x86/kernel/xsave.c index 782c3a362ec6..37e68fc5e24a 100644 --- a/arch/x86/kernel/xsave.c +++ b/arch/x86/kernel/xsave.c @@ -99,7 +99,7 @@ int save_i387_xstate(void __user *buf) if (err) return err; - if (task_thread_info(tsk)->status & TS_XSAVE) + if (use_xsave()) err = xsave_user(buf); else err = fxsave_user(buf); @@ -109,14 +109,14 @@ int save_i387_xstate(void __user *buf) task_thread_info(tsk)->status &= ~TS_USEDFPU; stts(); } else { - if (__copy_to_user(buf, &tsk->thread.xstate->fxsave, + if (__copy_to_user(buf, &tsk->thread.fpu.state->fxsave, xstate_size)) return -1; } clear_used_math(); /* trigger finit */ - if (task_thread_info(tsk)->status & TS_XSAVE) { + if (use_xsave()) { struct _fpstate __user *fx = buf; struct _xstate __user *x = buf; u64 xstate_bv; @@ -225,7 +225,7 @@ int restore_i387_xstate(void __user *buf) clts(); task_thread_info(current)->status |= TS_USEDFPU; } - if (task_thread_info(tsk)->status & TS_XSAVE) + if (use_xsave()) err = restore_user_xstate(buf); else err = fxrstor_checking((__force struct i387_fxsave_struct *) |