diff options
Diffstat (limited to 'arch/arc/kernel')
| -rw-r--r-- | arch/arc/kernel/process.c | 23 | ||||
| -rw-r--r-- | arch/arc/kernel/signal.c | 24 | ||||
| -rw-r--r-- | arch/arc/kernel/stacktrace.c | 21 | ||||
| -rw-r--r-- | arch/arc/kernel/unaligned.c | 2 |
4 files changed, 37 insertions, 33 deletions
diff --git a/arch/arc/kernel/process.c b/arch/arc/kernel/process.c index fdd89715d2d3..98c00a2d4dd9 100644 --- a/arch/arc/kernel/process.c +++ b/arch/arc/kernel/process.c @@ -192,29 +192,6 @@ int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu) return 0; } -/* - * API: expected by schedular Code: If thread is sleeping where is that. - * What is this good for? it will be always the scheduler or ret_from_fork. - * So we hard code that anyways. - */ -unsigned long thread_saved_pc(struct task_struct *t) -{ - struct pt_regs *regs = task_pt_regs(t); - unsigned long blink = 0; - - /* - * If the thread being queried for in not itself calling this, then it - * implies it is not executing, which in turn implies it is sleeping, - * which in turn implies it got switched OUT by the schedular. - * In that case, it's kernel mode blink can reliably retrieved as per - * the picture above (right above pt_regs). - */ - if (t != current && t->state != TASK_RUNNING) - blink = *((unsigned int *)regs - 1); - - return blink; -} - int elf_check_arch(const struct elf32_hdr *x) { unsigned int eflags; diff --git a/arch/arc/kernel/signal.c b/arch/arc/kernel/signal.c index 114234e83caa..edda76fae83f 100644 --- a/arch/arc/kernel/signal.c +++ b/arch/arc/kernel/signal.c @@ -67,7 +67,7 @@ stash_usr_regs(struct rt_sigframe __user *sf, struct pt_regs *regs, sigset_t *set) { int err; - err = __copy_to_user(&(sf->uc.uc_mcontext.regs), regs, + err = __copy_to_user(&(sf->uc.uc_mcontext.regs.scratch), regs, sizeof(sf->uc.uc_mcontext.regs.scratch)); err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(sigset_t)); @@ -83,7 +83,7 @@ static int restore_usr_regs(struct pt_regs *regs, struct rt_sigframe __user *sf) if (!err) set_current_blocked(&set); - err |= __copy_from_user(regs, &(sf->uc.uc_mcontext.regs), + err |= __copy_from_user(regs, &(sf->uc.uc_mcontext.regs.scratch), sizeof(sf->uc.uc_mcontext.regs.scratch)); return err; @@ -131,6 +131,15 @@ SYSCALL_DEFINE0(rt_sigreturn) /* Don't restart from sigreturn */ syscall_wont_restart(regs); + /* + * Ensure that sigreturn always returns to user mode (in case the + * regs saved on user stack got fudged between save and sigreturn) + * Otherwise it is easy to panic the kernel with a custom + * signal handler and/or restorer which clobberes the status32/ret + * to return to a bogus location in kernel mode. + */ + regs->status32 |= STATUS_U_MASK; + return regs->r0; badframe: @@ -229,8 +238,11 @@ setup_rt_frame(struct ksignal *ksig, sigset_t *set, struct pt_regs *regs) /* * handler returns using sigreturn stub provided already by userpsace + * If not, nuke the process right away */ - BUG_ON(!(ksig->ka.sa.sa_flags & SA_RESTORER)); + if(!(ksig->ka.sa.sa_flags & SA_RESTORER)) + return 1; + regs->blink = (unsigned long)ksig->ka.sa.sa_restorer; /* User Stack for signal handler will be above the frame just carved */ @@ -296,12 +308,12 @@ static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) { sigset_t *oldset = sigmask_to_save(); - int ret; + int failed; /* Set up the stack frame */ - ret = setup_rt_frame(ksig, oldset, regs); + failed = setup_rt_frame(ksig, oldset, regs); - signal_setup_done(ret, ksig, 0); + signal_setup_done(failed, ksig, 0); } void do_signal(struct pt_regs *regs) diff --git a/arch/arc/kernel/stacktrace.c b/arch/arc/kernel/stacktrace.c index 9ce47cfe2303..92320d6f737c 100644 --- a/arch/arc/kernel/stacktrace.c +++ b/arch/arc/kernel/stacktrace.c @@ -43,6 +43,10 @@ static void seed_unwind_frame_info(struct task_struct *tsk, struct pt_regs *regs, struct unwind_frame_info *frame_info) { + /* + * synchronous unwinding (e.g. dump_stack) + * - uses current values of SP and friends + */ if (tsk == NULL && regs == NULL) { unsigned long fp, sp, blink, ret; frame_info->task = current; @@ -61,12 +65,17 @@ static void seed_unwind_frame_info(struct task_struct *tsk, frame_info->regs.r63 = ret; frame_info->call_frame = 0; } else if (regs == NULL) { + /* + * Asynchronous unwinding of sleeping task + * - Gets SP etc from task's pt_regs (saved bottom of kernel + * mode stack of task) + */ frame_info->task = tsk; - frame_info->regs.r27 = KSTK_FP(tsk); - frame_info->regs.r28 = KSTK_ESP(tsk); - frame_info->regs.r31 = KSTK_BLINK(tsk); + frame_info->regs.r27 = TSK_K_FP(tsk); + frame_info->regs.r28 = TSK_K_ESP(tsk); + frame_info->regs.r31 = TSK_K_BLINK(tsk); frame_info->regs.r63 = (unsigned int)__switch_to; /* In the prologue of __switch_to, first FP is saved on stack @@ -83,6 +92,10 @@ static void seed_unwind_frame_info(struct task_struct *tsk, frame_info->call_frame = 0; } else { + /* + * Asynchronous unwinding of intr/exception + * - Just uses the pt_regs passed + */ frame_info->task = tsk; frame_info->regs.r27 = regs->fp; @@ -95,7 +108,7 @@ static void seed_unwind_frame_info(struct task_struct *tsk, #endif -static noinline unsigned int +notrace noinline unsigned int arc_unwind_core(struct task_struct *tsk, struct pt_regs *regs, int (*consumer_fn) (unsigned int, void *), void *arg) { diff --git a/arch/arc/kernel/unaligned.c b/arch/arc/kernel/unaligned.c index 7ff5b5c183bb..74db59b6f392 100644 --- a/arch/arc/kernel/unaligned.c +++ b/arch/arc/kernel/unaligned.c @@ -12,6 +12,7 @@ */ #include <linux/types.h> +#include <linux/perf_event.h> #include <linux/ptrace.h> #include <linux/uaccess.h> #include <asm/disasm.h> @@ -253,6 +254,7 @@ int misaligned_fixup(unsigned long address, struct pt_regs *regs, } } + perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, address); return 0; fault: |