From: David Howells <dhowells@redhat.com>
The attached patch fixes three debugging problems in the frv arch:
(1) Single-stepping in userspace steps through into the kernel-mode interrupt
handler when a hardware interrupt happens, and sometimes it gets past
where the debug-mode handler would normally catch it. This patch extends
the range of detected PC values.
(2) When setting up the kernel-mode exception frame from the debug-mode
handler for a userspace debugging event, we weren't setting the LR
register to generate a return to the exception handler epilogue.
(3) sys_ptrace() now needs to "put" the inferior task_struct not "free" it as
was done in 2.4.
Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/arch/frv/kernel/break.S | 7 +++++++
25-akpm/arch/frv/kernel/ptrace.c | 2 +-
2 files changed, 8 insertions(+), 1 deletion(-)
diff -puN arch/frv/kernel/break.S~frv-debugging-fixes arch/frv/kernel/break.S
--- 25/arch/frv/kernel/break.S~frv-debugging-fixes Thu Dec 16 14:43:05 2004
+++ 25-akpm/arch/frv/kernel/break.S Thu Dec 16 14:43:05 2004
@@ -202,6 +202,10 @@ __break_step:
setlo %lo(__entry_kernel_external_interrupt),gr3
subcc gr2,gr3,gr0,icc0
beq icc0,#2,__break_step_kernel_external_interrupt
+ sethi.p %hi(__entry_uspace_external_interrupt),gr3
+ setlo %lo(__entry_uspace_external_interrupt),gr3
+ subcc gr2,gr3,gr0,icc0
+ beq icc0,#2,__break_step_uspace_external_interrupt
LEDS 0x2007,gr2
@@ -483,6 +487,9 @@ __break_no_user_sstep:
movgs gr2,bpsr
# return through remainder of the exception prologue
+ # - need to load gr23 with return handler address
+ sethi.p %hi(__entry_return_from_user_exception),gr23
+ setlo %lo(__entry_return_from_user_exception),gr23
sethi.p %hi(__entry_common),gr3
setlo %lo(__entry_common),gr3
movgs gr3,bpcsr
diff -puN arch/frv/kernel/ptrace.c~frv-debugging-fixes arch/frv/kernel/ptrace.c
--- 25/arch/frv/kernel/ptrace.c~frv-debugging-fixes Thu Dec 16 14:43:05 2004
+++ 25-akpm/arch/frv/kernel/ptrace.c Thu Dec 16 14:43:05 2004
@@ -358,7 +358,7 @@ asmlinkage int sys_ptrace(long request,
break;
}
out_tsk:
- free_task_struct(child);
+ put_task_struct(child);
out:
unlock_kernel();
return ret;
_