From 9b6dba9e0798325dab427b9d60c61630ccc39b28 Mon Sep 17 00:00:00 2001 From: Brian Gerst Date: Sun, 21 Mar 2010 09:00:44 -0400 Subject: [PATCH] x86: Merge simd_math_error() into math_error() The only difference between FPU and SIMD exceptions is where the status bits are read from (cwd/swd vs. mxcsr). This also fixes the discrepency introduced by commit adf77bac, which fixed FPU but not SIMD. Signed-off-by: Brian Gerst LKML-Reference: <1269176446-2489-3-git-send-email-brgerst@gmail.com> Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/traps.h | 2 +- arch/x86/kernel/irqinit.c | 2 +- arch/x86/kernel/traps.c | 100 +++++++++++------------------------ 3 files changed, 34 insertions(+), 70 deletions(-) diff --git a/arch/x86/include/asm/traps.h b/arch/x86/include/asm/traps.h index 4da91ad69e0d..f66cda56781d 100644 --- a/arch/x86/include/asm/traps.h +++ b/arch/x86/include/asm/traps.h @@ -79,7 +79,7 @@ static inline int get_si_code(unsigned long condition) extern int panic_on_unrecovered_nmi; -void math_error(void __user *); +void math_error(struct pt_regs *, int, int); void math_emulate(struct math_emu_info *); #ifndef CONFIG_X86_32 asmlinkage void smp_thermal_interrupt(void); 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/traps.c b/arch/x86/kernel/traps.c index a16c9dfe6b70..a472992cecdc 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -595,36 +595,48 @@ static int kernel_math_error(struct pt_regs *regs, const char *str, int trapnr) * 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; siginfo_t info; - unsigned short cwd, swd, err; + unsigned short err; /* * 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 */ /* @@ -663,55 +675,7 @@ dotraplinkage void do_coprocessor_error(struct pt_regs *regs, long error_code) 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 @@ -727,7 +691,7 @@ do_simd_coprocessor_error(struct pt_regs *regs, long error_code) return; #endif - simd_math_error((void __user *)regs->ip); + math_error(regs, error_code, 19); } dotraplinkage void -- 2.34.1