Re: [Qemu-devel] [PATCH] hw: improve multiboot module loading

[Alexander Graf]

On 07.04.2011, at 14:07, Ralf Ramsauer wrote:

> On 07.04.2011 um 10:38, Alexander Graf wrote:
>> 
>> Also, I just realized that you did miss another small part that needs 
>> change. A few lines above, there is code to interpret the modules right 
>> before that as well:
>> 
>>   if (initrd_filename) {
>>       const char *r = initrd_filename;
>>       mbs.mb_buf_size += strlen(r) + 1;
>>       mbs.mb_mods_avail = 1;
>>       while ((r = strchr(r, ','))) {
>>          mbs.mb_mods_avail++;
>>          r++;
>>       }
>>       mbs.mb_buf_size += MB_MOD_SIZE * mbs.mb_mods_avail;
>>   }
>> 
>> This code would need some change as well, as now the mb_buf_size field is 
>> incorrect. It doesn't really hurt, but is bad style to not use the exact 
>> amount of memory we need to.
> 
> You're right, I didn't look at this section. But now i had a deeper look into 
> the code, and I noticed the the mb_buf size seems to be incorrect anyway.
> 
> Look at this line:
> 
> mbs.mb_buf_size += strlen(r) + 1;
> 
> If I start qemu with the option -initrd "mod1 arg=bla, mod2 arg=foo, mod3 
> arg=bar", then r contains
> "mod1 arg=bla, mod2 arg=foo, mod3 arg=bar", so the commas and spaces after 
> the comma are counted for the size of the multiboot command line.
> Yes, this doesn't really hurt, but it's nevertheless not the exact amount of 
> memory. I'll try to fix it.

Good point. Thanks!


Alex