Daniel Phillips wrote: > On Tuesday 02 August 2005 07:30, Patrick McHardy wrote: > > IIRC Linus called the whole swapping over ISCSI idea > > broken because apparently even userspace needs to allocate memory in > > some situations to make things work. > > Even a user space task may run in PF_MEMALLOC mode (and so guarantee its > syscalls access to a modest amount of working memory) so long as it follows > the same rules as a kernel task: all per-request memory usage must be > statically analyzable and bounded. But I am getting ahead of myself: the > immediate challenge is to deal accurately with the network-receive facet of > this multi-facetted problem.
Imagine a IPsec-SA timing out just in this case and (nearly) all user space pages swapped out. We need to renegotiate an IPsec-SA with someone, which needs the ISAKMP-daemon, which is completly swapped out. But we have no memory to swap it in, since we cannot swap out without transferring to our remote "disk" over an IPsec secured connection. Ugly; you see. That kind of things makes Linus shudder, I think. Regards Ingo Oeser - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
