Rusty Russell wrote:
> On Fri, 2007-02-09 at 01:35 -0800, Andrew Morton wrote:
>
>> On Fri, 09 Feb 2007 20:20:27 +1100 Rusty Russell <rusty at rustcorp.com.au> wrote:
>>
>>
>>> +#define log(...) \
>>> + do { \
>>> + mm_segment_t oldfs = get_fs(); \
>>> + char buf[100]; \
>>> + sprintf(buf, "lguest:" __VA_ARGS__); \
>>> + set_fs(KERNEL_DS); \
>>> + sys_write(1, buf, strlen(buf)); \
>>> + set_fs(oldfs); \
>>> + } while(0)
>>>
>> Due to gcc shortcomings, each instance of this will chew an additional 100
>> bytes of stack. Unless they fixed it recently. Is a bit of a timebomb. I
>> guess ksaprintf() could be used.
>>
>> It also looks a bit, umm, innovative.
>>
>
> It's also unused 8)
>
> It's an extremely useful macro for doing grossly invasive logging of the
> guest. I'll drop it if you prefer.
>
Yes, it is a bit, umm, innovative. If it is going to be kept, even if
just for devel logging, you should disable interrupts around it.
Changing segments is not a normal thing to do.
Zach
