Re: Oopsing cryptoapi (or loop device?) on 2.6.*

[Bill Davidsen <davidsen@tmr.com>]

James Morris wrote:
> On Sun, 15 Feb 2004, Jari Ruusu wrote:
> 
> 
>>Jan Rychter wrote:
>>
>>>FWIW, I've just tried loop-AES with 2.4.24, after using cryptoapi for a
>>>number of years. My machine froze dead in the midst of copying 2.8GB of
>>>data onto my file-backed reiserfs encrypted loopback mount.
>>>
>>>Since the system didn't ever freeze on me before and since I've had zero
>>>problems with cryptoapi, I attribute the freeze to loop-AES.
>>>
>>>Yes, I know this isn't a good bugreport...
>>
>>Is there any particular reason why you insist on using file backed loops?
>>
>>File backed loops have hard to fix re-entry problem: GFP_NOFS memory
>>allocations that cause dirty pages to written out to file backed loop, will
>>have to re-enter the file system anyway to complete the write. This causes
>>deadlocks. Same deadlocks are there in mainline loop+cryptoloop combo.
> 
> 
> Given the security issues, and the above problems, we should probably just
> remove cryptoloop from the kernel and wait for something with a better
> design.

I hope you're kidding... one of the reasons for going to 2.6 is that you 
no longer have to patch your kernel to get cryptoloop. That is a real 
issue in some organizations, which only allow vendor or kernel.org kernels.

If you start dropping features which work for most people but aren't 
perfect, you will wind up with a microkernel indeed.

-- 
bill davidsen <davidsen@tmr.com>
   CTO TMR Associates, Inc
   Doing interesting things with small computers since 1979