At Mon, 19 Nov 2007 17:14:15 -0800, Jeremy Fitzhardinge wrote: > > Takashi Iwai wrote: > > I took at this problem (as I have an nvidia card on one of my > > workstations), and found out that the following suffer from > > EXPORT_SYMBOL_GPL changes: > > > > Which kernel version are you using? This is different in .24-rc > compared to .23.
24-rc2. 23 has no problem, as you know :) > > * local_disable_irq(), local_irq_save*(), etc. > > > > These should be OK either way. pv_irq_ops is not _GPL. Right. I thought it somehow involved with other pv ops indirectly, but it seems not. > > * MSR-related macros like rdmsr(), wrmsr(), read_cr0(), etc. > > wbinvd(), too. > > > > These could reasonably use the the native_* versions anyway, since the > driver won't be being used in an environment where these won't work. > Perhaps they should be split out separate from the gdt/ldt operations, > which they should have no business touching. Yes, that's possible. > > * pmd_val(), pgd_val(), etc are all involved with pv_mm_ops. > > pmd_large() and pmd_bad() is also indirectly involved. > > __flush_tlb() and friends suffer, too. > > > > Yeah, I guess they can be expected to play with pagetables. > > > The easiest workaround I found was to undefine CONFIG_PARAVIRT before > > inclusion of linux kernel headers, but it is really ugly and hacky. > > > > Yeah. It will explode if you are running in a virtual environment which > still gives the virtual machine graphics hardware access. Yes. More over, there is no guarantee that this will be built properly in the future. It's a kind of coincident that the driver is built. If any non-paravirt implementation accesses an exported symbol instead of inlining, then this won't work, too. > > Redefinig with raw_*() and native_*() is another way, but it takes > > much more work than defining these primitive functions in assembly. > > > > So, in short, with EXPORT_SYMBOL_GPL change, it's pretty hard to write > > a non-GPL driver in a same manner... > > > > Yeah. I think removing the difference between PARAVIRT and non-PARAVIRT > is enough to justify the exports. If we want to make the policy > decision that modules can't use pagetable or msr operations at all, then > that's a separate decision which can be applied uniformly to PARAVIRT > and non-PARAVIRT. Agreed. thanks, Takashi - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
