于 2011/12/16,星期五 15:23, Sasha Levin 写道: > On Fri, 2011-12-16 at 15:02 +0800, Zang Hongyong wrote: >> 于 2011/12/16,星期五 13:50, Sasha Levin 写道: >>> On Fri, 2011-12-16 at 09:01 +0800, zanghongyong@xxxxxxxxxx wrote: >>>> If a guest's ram_size exceeds KVM_32BIT_GAP_START, the corresponding kvm tool's >>>> virtual address size should be (ram_size + KVM_32BIT_GAP_SIZE), rather than ram_size. >>> You're right. >>> >>> There are more places than just the madvise() code which make the same >>> error you've spotted (for example, the memslot allocation code), so >>> instead of trying to fix all of them I'd suggest to just update ram_size >>> in kvm__arch_init() before allocating everything - that should fix all >>> of them at once. >>> >> Yes. There are other scenarios with the same error. >> However ram_size sometimes means real guest ram size, and sometimes >> means virtual address >> size of kvm tool's user space. Shall we define a new variable? > Let's keep it simple. If the user requests more than RAM than > KVM_32BIT_GAP_START just increase it by KVM_32BIT_GAP_SIZE, this way > mapped size == guest size always (we can madvise(MADV_DONTNEED) the gap > in the mmapped ram). > > Since a user which requests more than KVM_32BIT_GAP_START will have to > be on 64bit host anyway, there shouldn't be any issue with that. > Do you mean increase *kvm->ram_size* by KVM_32BIT_GAP_SIZE? but sometimes kvm->ram_size stands for guest physical ram size (for example in kvm__init_ram() code). -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
