diff options
| author | Petr Tesarik <ptesarik@suse.cz> | 2007-12-12 17:23:34 +0300 |
|---|---|---|
| committer | Tony Luck <tony.luck@intel.com> | 2008-02-08 23:01:18 +0300 |
| commit | 3b2ce0b17824c42bc2e46f7dd903b4acf5e9fff9 (patch) | |
| tree | acf3913f8c0a479615060ffed4cec9283047761c /include/asm-ia64 | |
| parent | 5aa92ffda1b6244b4a248df0b95c07d183ab96d2 (diff) | |
| download | linux-3b2ce0b17824c42bc2e46f7dd903b4acf5e9fff9.tar.xz | |
[IA64] Synchronize kernel RSE to user-space and back
This is base kernel patch for ptrace RSE bug. It's basically a backport
from the utrace RSE patch I sent out several weeks ago. please review.
when a thread is stopped (ptraced), debugger might change thread's user
stack (change memory directly), and we must avoid the RSE stored in
kernel to override user stack (user space's RSE is newer than kernel's
in the case). To workaround the issue, we copy kernel RSE to user RSE
before the task is stopped, so user RSE has updated data. we then copy
user RSE to kernel after the task is resummed from traced stop and
kernel will use the newer RSE to return to user.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Petr Tesarik <ptesarik@suse.cz>
CC: Roland McGrath <roland@redhat.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Diffstat (limited to 'include/asm-ia64')
| -rw-r--r-- | include/asm-ia64/ptrace.h | 7 | ||||
| -rw-r--r-- | include/asm-ia64/thread_info.h | 2 |
2 files changed, 9 insertions, 0 deletions
diff --git a/include/asm-ia64/ptrace.h b/include/asm-ia64/ptrace.h index f4ef87a36236..13435f778b0c 100644 --- a/include/asm-ia64/ptrace.h +++ b/include/asm-ia64/ptrace.h @@ -292,6 +292,7 @@ struct switch_stack { unsigned long, long); extern void ia64_flush_fph (struct task_struct *); extern void ia64_sync_fph (struct task_struct *); + extern void ia64_sync_krbs(void); extern long ia64_sync_user_rbs (struct task_struct *, struct switch_stack *, unsigned long, unsigned long); @@ -303,6 +304,12 @@ struct switch_stack { extern void ia64_increment_ip (struct pt_regs *pt); extern void ia64_decrement_ip (struct pt_regs *pt); + extern void ia64_ptrace_stop(void); + #define arch_ptrace_stop(code, info) \ + ia64_ptrace_stop() + #define arch_ptrace_stop_needed(code, info) \ + (!test_thread_flag(TIF_RESTORE_RSE)) + #endif /* !__KERNEL__ */ /* pt_all_user_regs is used for PTRACE_GETREGS PTRACE_SETREGS */ diff --git a/include/asm-ia64/thread_info.h b/include/asm-ia64/thread_info.h index 5a2c47957069..93d83cbe0c8c 100644 --- a/include/asm-ia64/thread_info.h +++ b/include/asm-ia64/thread_info.h @@ -94,6 +94,7 @@ extern void tsk_clear_notify_resume(struct task_struct *tsk); #define TIF_MCA_INIT 18 /* this task is processing MCA or INIT */ #define TIF_DB_DISABLED 19 /* debug trap disabled for fsyscall */ #define TIF_FREEZE 20 /* is freezing for suspend */ +#define TIF_RESTORE_RSE 21 /* user RBS is newer than kernel RBS */ #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) @@ -107,6 +108,7 @@ extern void tsk_clear_notify_resume(struct task_struct *tsk); #define _TIF_MCA_INIT (1 << TIF_MCA_INIT) #define _TIF_DB_DISABLED (1 << TIF_DB_DISABLED) #define _TIF_FREEZE (1 << TIF_FREEZE) +#define _TIF_RESTORE_RSE (1 << TIF_RESTORE_RSE) /* "work to do on user-return" bits */ #define TIF_ALLWORK_MASK (_TIF_SIGPENDING|_TIF_NOTIFY_RESUME|_TIF_SYSCALL_AUDIT|\ |