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Diffstat (limited to 'arch/powerpc/kernel/ptrace.c')
-rw-r--r--arch/powerpc/kernel/ptrace.c120
1 files changed, 89 insertions, 31 deletions
diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c
index 8feb93e7890c..6b66cd85b433 100644
--- a/arch/powerpc/kernel/ptrace.c
+++ b/arch/powerpc/kernel/ptrace.c
@@ -22,6 +22,7 @@
#include <linux/errno.h>
#include <linux/ptrace.h>
#include <linux/regset.h>
+#include <linux/tracehook.h>
#include <linux/elf.h>
#include <linux/user.h>
#include <linux/security.h>
@@ -703,7 +704,7 @@ void user_enable_single_step(struct task_struct *task)
if (regs != NULL) {
#if defined(CONFIG_40x) || defined(CONFIG_BOOKE)
- task->thread.dbcr0 = DBCR0_IDM | DBCR0_IC;
+ task->thread.dbcr0 |= DBCR0_IDM | DBCR0_IC;
regs->msr |= MSR_DE;
#else
regs->msr |= MSR_SE;
@@ -716,9 +717,16 @@ void user_disable_single_step(struct task_struct *task)
{
struct pt_regs *regs = task->thread.regs;
+
+#if defined(CONFIG_BOOKE)
+ /* If DAC then do not single step, skip */
+ if (task->thread.dabr)
+ return;
+#endif
+
if (regs != NULL) {
#if defined(CONFIG_40x) || defined(CONFIG_BOOKE)
- task->thread.dbcr0 = 0;
+ task->thread.dbcr0 &= ~(DBCR0_IC | DBCR0_IDM);
regs->msr &= ~MSR_DE;
#else
regs->msr &= ~MSR_SE;
@@ -727,22 +735,76 @@ void user_disable_single_step(struct task_struct *task)
clear_tsk_thread_flag(task, TIF_SINGLESTEP);
}
-static int ptrace_set_debugreg(struct task_struct *task, unsigned long addr,
+int ptrace_set_debugreg(struct task_struct *task, unsigned long addr,
unsigned long data)
{
- /* We only support one DABR and no IABRS at the moment */
+ /* For ppc64 we support one DABR and no IABR's at the moment (ppc64).
+ * For embedded processors we support one DAC and no IAC's at the
+ * moment.
+ */
if (addr > 0)
return -EINVAL;
- /* The bottom 3 bits are flags */
+ /* The bottom 3 bits in dabr are flags */
if ((data & ~0x7UL) >= TASK_SIZE)
return -EIO;
- /* Ensure translation is on */
+#ifndef CONFIG_BOOKE
+
+ /* For processors using DABR (i.e. 970), the bottom 3 bits are flags.
+ * It was assumed, on previous implementations, that 3 bits were
+ * passed together with the data address, fitting the design of the
+ * DABR register, as follows:
+ *
+ * bit 0: Read flag
+ * bit 1: Write flag
+ * bit 2: Breakpoint translation
+ *
+ * Thus, we use them here as so.
+ */
+
+ /* Ensure breakpoint translation bit is set */
if (data && !(data & DABR_TRANSLATION))
return -EIO;
+ /* Move contents to the DABR register */
task->thread.dabr = data;
+
+#endif
+#if defined(CONFIG_BOOKE)
+
+ /* As described above, it was assumed 3 bits were passed with the data
+ * address, but we will assume only the mode bits will be passed
+ * as to not cause alignment restrictions for DAC-based processors.
+ */
+
+ /* DAC's hold the whole address without any mode flags */
+ task->thread.dabr = data & ~0x3UL;
+
+ if (task->thread.dabr == 0) {
+ task->thread.dbcr0 &= ~(DBSR_DAC1R | DBSR_DAC1W | DBCR0_IDM);
+ task->thread.regs->msr &= ~MSR_DE;
+ return 0;
+ }
+
+ /* Read or Write bits must be set */
+
+ if (!(data & 0x3UL))
+ return -EINVAL;
+
+ /* Set the Internal Debugging flag (IDM bit 1) for the DBCR0
+ register */
+ task->thread.dbcr0 = DBCR0_IDM;
+
+ /* Check for write and read flags and set DBCR0
+ accordingly */
+ if (data & 0x1UL)
+ task->thread.dbcr0 |= DBSR_DAC1R;
+ if (data & 0x2UL)
+ task->thread.dbcr0 |= DBSR_DAC1W;
+
+ task->thread.regs->msr |= MSR_DE;
+#endif
return 0;
}
@@ -953,31 +1015,24 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
return ret;
}
-static void do_syscall_trace(void)
+/*
+ * We must return the syscall number to actually look up in the table.
+ * This can be -1L to skip running any syscall at all.
+ */
+long do_syscall_trace_enter(struct pt_regs *regs)
{
- /* the 0x80 provides a way for the tracing parent to distinguish
- between a syscall stop and SIGTRAP delivery */
- ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
- ? 0x80 : 0));
-
- /*
- * this isn't the same as continuing with a signal, but it will do
- * for normal use. strace only continues with a signal if the
- * stopping signal is not SIGTRAP. -brl
- */
- if (current->exit_code) {
- send_sig(current->exit_code, current, 1);
- current->exit_code = 0;
- }
-}
+ long ret = 0;
-void do_syscall_trace_enter(struct pt_regs *regs)
-{
secure_computing(regs->gpr[0]);
- if (test_thread_flag(TIF_SYSCALL_TRACE)
- && (current->ptrace & PT_PTRACED))
- do_syscall_trace();
+ if (test_thread_flag(TIF_SYSCALL_TRACE) &&
+ tracehook_report_syscall_entry(regs))
+ /*
+ * Tracing decided this syscall should not happen.
+ * We'll return a bogus call number to get an ENOSYS
+ * error, but leave the original number in regs->gpr[0].
+ */
+ ret = -1L;
if (unlikely(current->audit_context)) {
#ifdef CONFIG_PPC64
@@ -995,16 +1050,19 @@ void do_syscall_trace_enter(struct pt_regs *regs)
regs->gpr[5] & 0xffffffff,
regs->gpr[6] & 0xffffffff);
}
+
+ return ret ?: regs->gpr[0];
}
void do_syscall_trace_leave(struct pt_regs *regs)
{
+ int step;
+
if (unlikely(current->audit_context))
audit_syscall_exit((regs->ccr&0x10000000)?AUDITSC_FAILURE:AUDITSC_SUCCESS,
regs->result);
- if ((test_thread_flag(TIF_SYSCALL_TRACE)
- || test_thread_flag(TIF_SINGLESTEP))
- && (current->ptrace & PT_PTRACED))
- do_syscall_trace();
+ step = test_thread_flag(TIF_SINGLESTEP);
+ if (step || test_thread_flag(TIF_SYSCALL_TRACE))
+ tracehook_report_syscall_exit(regs, step);
}