>>> On Wed, May 16, 2007 at 7:47 AM, in message <[EMAIL PROTECTED]>, Avi Kivity <[EMAIL PROTECTED]> wrote: > Gregory Haskins wrote: >> Newer userspace may run on an older kernel. Therefore we need a way to >> check the capabilities of the kernel so that we can downgrade userspace >> dynamically if necessary >> >> Signed- off- by: Gregory Haskins <[EMAIL PROTECTED]> >> --- >> >> qemu/qemu- kvm.c | 19 +++++++++++++++++++ >> user/kvmctl.c | 14 ++++++++++++++ >> user/kvmctl.h | 5 +++++ >> 3 files changed, 38 insertions(+), 0 deletions(- ) >> >> diff -- git a/qemu/qemu- kvm.c b/qemu/qemu- kvm.c >> index 59e79bf..6096f21 100644 >> --- a/qemu/qemu- kvm.c >> +++ b/qemu/qemu- kvm.c >> @@ - 697,6 +697,25 @@ int kvm_qemu_init() >> int kvm_qemu_create_context(void) >> { >> int i; >> + uint64_t ext; >> + >> + if (kvm_check_extension(kvm_context, &ext) < 0) { >> + kvm_qemu_destroy(); >> + return - 1; >> + } >> + >> + if (!(ext & KVM_EXTENSION_LAPIC) && kvm_apic_level) { >> + /* >> + * Opps... the kernel doesnt support apic- emulation even though >> + * the user wants it. We must turn this off and warn the user >> + */ >> + kvm_apic_level = 0; >> + >> + /* FIXME: We should log this officially */ >> + printf("WARNING: older kernel does not support apic " \ >> + "emulation. Falling back to userspace emulation. Upgrade " \ >> + "your kernel/modules\n"); >> + } >> > > The user may not be in a position to upgrade the kernel. Think distro > kernel and userspace. A warning is a bit severe.
Ack. Should I drop the printf all together? Or just get rid of the "WARNING" and "please upgrade" part?. Also, is there a better way to log in this thing (instead of to stdout?) All the rest of your comments: Ack. > >> >> if (kvm_create(kvm_context, phys_ram_size, kvm_apic_level, >> (void**)&phys_ram_base) < 0) { >> diff -- git a/user/kvmctl.c b/user/kvmctl.c >> index ea86426..fcabc1a 100644 >> --- a/user/kvmctl.c >> +++ b/user/kvmctl.c >> @@ - 889,3 +889,17 @@ int kvm_set_signal_mask(kvm_context_t kvm, int vcpu, > const sigset_t *sigset) >> free(sigmask); >> return r; >> } >> + >> +int kvm_check_extension(kvm_context_t kvm, uint64_t *ext) >> +{ >> + *ext = 0; >> + >> + int r = ioctl(kvm- >fd, KVM_CHECK_EXTENSION, KVM_APIC_MSG); >> + if (r < 0) >> + return r; >> > > - errno for new code, please. > >> + >> + if (r) >> + *ext |= KVM_EXTENSION_LAPIC; >> + >> + return 0; >> +} >> > > How about a struct with a field per extension instead of bitmasks? ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel