Re: [v2][PATCH 3/3] powerpc/kgdb: restore current_thread_info properly

["tiejun.chen" <tiejun.chen@windriver.com>]

On 08/23/2012 11:14 AM, Nicholas A. Bellinger wrote:
> On Thu, 2012-08-23 at 10:10 +0800, Tiejun Chen wrote:
>> For powerpc BooKE and e200, singlestep is handled on the critical/dbg
>> exception stack. This causes current_thread_info() to fail for kgdb
>> internal, so previously We work around this issue by copying
>> the thread_info from the kernel stack before calling kgdb_handle_exception,
>> and copying it back afterwards.
>>
>> But actually we don't do this properly. We should backup current_thread_info
>> then restore that when exit.
>>
>> Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com>
>> ---
>> v2: fix a typo in patch head description.
>>
>>  arch/powerpc/kernel/kgdb.c |   11 +++++++++--
>>  1 files changed, 9 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/powerpc/kernel/kgdb.c b/arch/powerpc/kernel/kgdb.c
>> index 05adb69..c470a40 100644
>> --- a/arch/powerpc/kernel/kgdb.c
>> +++ b/arch/powerpc/kernel/kgdb.c
>> @@ -25,6 +25,7 @@
>>  #include <asm/processor.h>
>>  #include <asm/machdep.h>
>>  #include <asm/debug.h>
>> +#include <linux/slab.h>
>>  
>>  /*
>>   * This table contains the mapping between PowerPC hardware trap types, and
>> @@ -153,6 +154,8 @@ static int kgdb_handle_breakpoint(struct pt_regs *regs)
>>  static int kgdb_singlestep(struct pt_regs *regs)
>>  {
>>  	struct thread_info *thread_info, *exception_thread_info;
>> +	struct thread_info *backup_current_thread_info = \
>> +		(struct thread_info *)kmalloc(sizeof(struct thread_info), GFP_KERNEL);
>>  
> 
> Looks like a rouge '\' in the above assignment..

Remove that :)

Thanks
Tiejun