lkml.org 
[lkml]   [2008]   [Dec]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
Subjectsg_set_page not usable for .bss?

On Monday 2008-12-01 23:02, John Haxby wrote:
>>>+ sg_init_table(sg, 2);
>>>+ sg_set_buf(&sg[0], data, n);
>>>+ strcpy(digest_password, sysrq_password);
>>>+ i = strlen(digest_password);
>>>+ sg_set_buf(&sg[1], digest_password, i);
>>
>> Could we directly use sysrq_password instead of copying it to
>> digest_password first?
>
> No :-) Eventually I discovered the reason my code wasn't working
> boils down to the definition of sg_set_buf:
>
> sg_set_page(sg, virt_to_page(buf), buflen, offset_in_page(buf))
>
> which doesn't work for sysrq_password. I don't know why I'll
> double check.

Well, sysrq_password is in the .bss section, where as digest_password
is on the heap due to being kmalloc'ed. Maybe that makes a difference?
Someone more versed with the virtual memory layer might know.

>+static char sysrq_password[64];
>[...]
>+ digest_password = kmalloc(sizeof(sysrq_password), GFP_KERNEL);


\
 
 \ /
  Last update: 2008-12-01 23:43    [W:0.037 / U:0.768 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site