diff options
Diffstat (limited to 'arch/mips/kernel/ptrace.c')
| -rw-r--r-- | arch/mips/kernel/ptrace.c | 40 |
1 files changed, 32 insertions, 8 deletions
diff --git a/arch/mips/kernel/ptrace.c b/arch/mips/kernel/ptrace.c index 510452812594..d544e774eea6 100644 --- a/arch/mips/kernel/ptrace.c +++ b/arch/mips/kernel/ptrace.c @@ -32,6 +32,7 @@ #include <asm/byteorder.h> #include <asm/cpu.h> +#include <asm/cpu-info.h> #include <asm/dsp.h> #include <asm/fpu.h> #include <asm/mipsregs.h> @@ -46,6 +47,26 @@ #define CREATE_TRACE_POINTS #include <trace/events/syscalls.h> +static void init_fp_ctx(struct task_struct *target) +{ + /* If FP has been used then the target already has context */ + if (tsk_used_math(target)) + return; + + /* Begin with data registers set to all 1s... */ + memset(&target->thread.fpu.fpr, ~0, sizeof(target->thread.fpu.fpr)); + + /* ...and FCSR zeroed */ + target->thread.fpu.fcr31 = 0; + + /* + * Record that the target has "used" math, such that the context + * just initialised, and any modifications made by the caller, + * aren't discarded. + */ + set_stopped_child_used_math(target); +} + /* * Called by kernel/ptrace.c when detaching.. * @@ -137,11 +158,15 @@ int ptrace_setfpregs(struct task_struct *child, __u32 __user *data) { union fpureg *fregs; u64 fpr_val; + u32 fcr31; + u32 value; + u32 mask; int i; if (!access_ok(VERIFY_READ, data, 33 * 8)) return -EIO; + init_fp_ctx(child); fregs = get_fpu_regs(child); for (i = 0; i < 32; i++) { @@ -149,8 +174,10 @@ int ptrace_setfpregs(struct task_struct *child, __u32 __user *data) set_fpr64(&fregs[i], 0, fpr_val); } - __get_user(child->thread.fpu.fcr31, data + 64); - child->thread.fpu.fcr31 &= ~FPU_CSR_ALL_X; + __get_user(value, data + 64); + fcr31 = child->thread.fpu.fcr31; + mask = current_cpu_data.fpu_msk31; + child->thread.fpu.fcr31 = (value & ~mask) | (fcr31 & mask); /* FIR may not be written. */ @@ -439,6 +466,8 @@ static int fpr_set(struct task_struct *target, /* XXX fcr31 */ + init_fp_ctx(target); + if (sizeof(target->thread.fpu.fpr[i]) == sizeof(elf_fpreg_t)) return user_regset_copyin(&pos, &count, &kbuf, &ubuf, &target->thread.fpu, @@ -660,12 +689,7 @@ long arch_ptrace(struct task_struct *child, long request, case FPR_BASE ... FPR_BASE + 31: { union fpureg *fregs = get_fpu_regs(child); - if (!tsk_used_math(child)) { - /* FP not yet used */ - memset(&child->thread.fpu, ~0, - sizeof(child->thread.fpu)); - child->thread.fpu.fcr31 = 0; - } + init_fp_ctx(child); #ifdef CONFIG_32BIT if (test_thread_flag(TIF_32BIT_FPREGS)) { /* |