Hugh Dickins <[EMAIL PROTECTED]> wrote: > > VMAs are a shared resource under NOMMU conditions. > > That's a disturbing remark.
Why? No-one complained when I first put up my rewrite patches three years ago. > Under precisely what NOMMU conditions? CONFIG_MMU=n. > I had thought Robin's suggestion very sensible; and throughout mm/ > it has seemed pretty random whether we pass an "mm" argument down > in addition to "vma", or just take vma->vm_mm at whatever level needs. > > You seem to be suggesting vma->vm_mm is dangerous when CONFIG_NOMMU, vm_mm is never set to anything other than NULL if CONFIG_MMU=n and it doesn't seem to be a problem. I don't think anything in the mm/ directory is left that looks at vm_mm once MMU support is disabled (in fact I've just checked, and I can compile with vm_mm #ifdef'd out) > but we MMU people are scarily unaware of that. If you're worryied that you can't compile anything for NOMMU, an FRV compiler is available, and a suitable NOMMU default config can be provided. Alternatively, you can pick ARM, M68K, ... > Perhaps you need to put #ifndef CONFIG_NOMMU around vm_mm in struct > vm_area_struct? I can if it makes you happier. It's not strictly necessary, but it does make the struct smaller which is good. David - 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/
