Hi Arun... :)

On Wed, Jul 11, 2012 at 6:01 PM, Arun KS [off-list ref] wrote:

I went ahead and made my __log_buf size to 1MB.
But the memory is not aligned to 1MB boundary. Here is what system.map shows.

c08ac400 b __warned.32427
c08ac404 b __log_buf
c09ac404 B console_set_on_cmdline
c09ac408 b idle_notifier
c09ac40c B sys_tz

so __log_buf resides in two 1M sections in parts and it needs two PTEs.

Then I added __aligned__(1024*1024) attribute to __log_buf array.
This time compiler error  "Error: alignment too large: 15 assumed"

But  __aligned_(32*1024) is working fine as below

c08b84c0 b __warned.32427
c08c0000 b __log_buf
c09c0000 B console_set_on_cmdline
c09c8000 b idle_notifier
c09c8004 B sys_tz

Is it not possible to align more than 32KB?
Any pointers?

when you said alignment, I quickly google and found this gcc page:
http://gcc.gnu.org/onlinedocs/gcc-3.2/gcc/Type-Attributes.html

to be honest, what went wrong here.... I guessed you need to check the
linker script...maybe something must be changed there.

-- 
regards,

Mulyadi Santosa
Freelance Linux trainer and consultant

blog: the-hydra.blogspot.com
training: mulyaditraining.blogspot.com