diff options
| author | David Mosberger-Tang <davidm@hpl.hp.com> | 2005-05-10 12:49:00 -0700 |
|---|---|---|
| committer | Tony Luck <tony.luck@intel.com> | 2005-05-17 14:07:10 -0700 |
| commit | 7f9eaedf894dbaa08c157832e9a6c9c03ffed1ed (patch) | |
| tree | 12a561efa197fdbe78ba74b576c28f132e04660a | |
| parent | 8800cea62025a5209d110c5fa5990429239d6eee (diff) | |
[IA64] Fix convert_to_non_syscall() so gdb inferior calls work again
Fix convert_to_non_syscall() so it arranges for the kernel to be left
via ia64_leave_kernel() rather than ia64_leave_syscall(). The latter
no longer tolerates being called with pSys=0 and pNonSys=1.
Signed-off-by: David Mosberger-Tang <davidm@hpl.hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
| -rw-r--r-- | arch/ia64/kernel/ptrace.c | 22 |
1 files changed, 21 insertions, 1 deletions
diff --git a/arch/ia64/kernel/ptrace.c b/arch/ia64/kernel/ptrace.c index c253fd5914f..9e730c7bf0c 100644 --- a/arch/ia64/kernel/ptrace.c +++ b/arch/ia64/kernel/ptrace.c @@ -705,12 +705,32 @@ convert_to_non_syscall (struct task_struct *child, struct pt_regs *pt, break; } + /* + * Note: at the time of this call, the target task is blocked + * in notify_resume_user() and by clearling PRED_LEAVE_SYSCALL + * (aka, "pLvSys") we redirect execution from + * .work_pending_syscall_end to .work_processed_kernel. + */ unw_get_pr(&prev_info, &pr); - pr &= ~(1UL << PRED_SYSCALL); + pr &= ~((1UL << PRED_SYSCALL) | (1UL << PRED_LEAVE_SYSCALL)); pr |= (1UL << PRED_NON_SYSCALL); unw_set_pr(&prev_info, pr); pt->cr_ifs = (1UL << 63) | cfm; + /* + * Clear the memory that is NOT written on syscall-entry to + * ensure we do not leak kernel-state to user when execution + * resumes. + */ + pt->r2 = 0; + pt->r3 = 0; + pt->r14 = 0; + memset(&pt->r16, 0, 16*8); /* clear r16-r31 */ + memset(&pt->f6, 0, 6*16); /* clear f6-f11 */ + pt->b7 = 0; + pt->ar_ccv = 0; + pt->ar_csd = 0; + pt->ar_ssd = 0; } static int |