diff options
Diffstat (limited to 'arch/mips/kernel/ptrace.c')
| -rw-r--r-- | arch/mips/kernel/ptrace.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/arch/mips/kernel/ptrace.c b/arch/mips/kernel/ptrace.c index 62e8ffd9370a..7fcadaaf330f 100644 --- a/arch/mips/kernel/ptrace.c +++ b/arch/mips/kernel/ptrace.c @@ -516,7 +516,15 @@ static int fpr_set_msa(struct task_struct *target, return 0; } -/* Copy the supplied NT_PRFPREG buffer to the floating-point context. */ +/* + * Copy the supplied NT_PRFPREG buffer to the floating-point context. + * + * We optimize for the case where `count % sizeof(elf_fpreg_t) == 0', + * which is supposed to have been guaranteed by the kernel before + * calling us, e.g. in `ptrace_regset'. We enforce that requirement, + * so that we can safely avoid preinitializing temporaries for + * partial register writes. + */ static int fpr_set(struct task_struct *target, const struct user_regset *regset, unsigned int pos, unsigned int count, @@ -524,6 +532,8 @@ static int fpr_set(struct task_struct *target, { int err; + BUG_ON(count % sizeof(elf_fpreg_t)); + /* XXX fcr31 */ init_fp_ctx(target); |