I don't have a ppc machine, this patch wasn't even compile tested, could you please review?
The commit a8a4b03ab95f ("powerpc: Hard wire PT_SOFTE value to 1 in ptrace & signals") changed ptrace_get_reg(PT_SOFTE) to report 0x1, but PTRACE_GETREGS still copies pt_regs->softe as is. This is not consistent and this breaks http://sourceware.org/systemtap/wiki/utrace/tests/user-regs-peekpoke Reported-by: Jan Kratochvil <jan.kratoch...@redhat.com> Signed-off-by: Oleg Nesterov <o...@redhat.com> --- arch/powerpc/kernel/ptrace.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c index 8c92feb..291acfb 100644 --- a/arch/powerpc/kernel/ptrace.c +++ b/arch/powerpc/kernel/ptrace.c @@ -363,11 +363,36 @@ static int gpr_get(struct task_struct *target, const struct user_regset *regset, BUILD_BUG_ON(offsetof(struct pt_regs, orig_gpr3) != offsetof(struct pt_regs, msr) + sizeof(long)); +#ifdef CONFIG_PPC64 + if (!ret) + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, + &target->thread.regs->orig_gpr3, + offsetof(struct pt_regs, orig_gpr3), + offsetof(struct pt_regs, softe)); + + if (!ret) { + unsigned long softe = 0x1; + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &softe, + offsetof(struct pt_regs, softe), + offsetof(struct pt_regs, softe) + + sizeof(softe)); + } + + BUILD_BUG_ON(offsetof(struct pt_regs, trap) != + offsetof(struct pt_regs, softe) + sizeof(long)); + + if (!ret) + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, + &target->thread.regs->trap, + offsetof(struct pt_regs, trap), + sizeof(struct user_pt_regs)); +#else if (!ret) ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &target->thread.regs->orig_gpr3, offsetof(struct pt_regs, orig_gpr3), sizeof(struct user_pt_regs)); +#endif if (!ret) ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf, sizeof(struct user_pt_regs), -1); -- 2.5.0