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Diffstat (limited to 'arch/x86/kernel/traps.c')
-rw-r--r--arch/x86/kernel/traps.c177
1 files changed, 50 insertions, 127 deletions
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 1168e4454188..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)
@@ -543,11 +534,11 @@ dotraplinkage void __kprobes do_debug(struct pt_regs *regs, long error_code)
/* DR6 may or may not be cleared by the CPU */
set_debugreg(0, 6);
+
/*
* The processor cleared BTF, so don't mark that we need it set.
*/
- clear_tsk_thread_flag(tsk, TIF_DEBUGCTLMSR);
- tsk->thread.debugctlmsr = 0;
+ clear_tsk_thread_flag(tsk, TIF_BLOCKSTEP);
/* Store the virtualized DR6 value */
tsk->thread.debugreg6 = dr6;
@@ -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