On 05/20/2010 09:37 AM, Chris Lalancette wrote:
On 05/19/2010 05:16 PM, Mohammed Gamal wrote:
This patch address bug report in https://bugs.launchpad.net/qemu/+bug/530077.
Failed vmentries were handled with handle_unhandled() which prints a rather
unfriendly message to the user. This patch separates handling vmentry failures
from unknown exit reasons and prints a friendly message to the user.
Signed-off-by: Mohammed Gamal<m.gamal005@xxxxxxxxx>
---
qemu-kvm.c | 16 +++++++++++++++-
1 files changed, 15 insertions(+), 1 deletions(-)
diff --git a/qemu-kvm.c b/qemu-kvm.c
index 35a4c8a..deb4df8 100644
--- a/qemu-kvm.c
+++ b/qemu-kvm.c
@@ -106,6 +106,20 @@ static int handle_unhandled(uint64_t reason)
return -EINVAL;
}
+static int handle_failed_vmentry(uint64_t reason)
+{
+ fprintf(stderr, "kvm: vm entry failed with error 0x%" PRIx64 "\n\n", reason);
+ fprintf(stderr, "If you're runnning a guest on an Intel machine, it can be\n");
+ fprintf(stderr, "most-likely due to the guest going into an invalid state\n");
+ fprintf(stderr, "for Intel VT. For example, the guest maybe running in big\n");
+ fprintf(stderr, "real mode which is not supported by Intel VT.\n\n");
+ fprintf(stderr, "You may want to try enabling real mode emulation in KVM.\n");
+ fprintf(stderr, "To Enable it, you may run the following commands as root:\n");
+ fprintf(stderr, "# rmmod kvm_intel\n");
+ fprintf(stderr, "# rmmod kvm\n");
+ fprintf(stderr, "# modprobe kvm_intel emulate_invalid_guest_state=1\n");
+ return -EINVAL;
+}
The thing is, there are other valid reasons for vmentry failure. A while ago I tracked
down a bug in the Linux kernel that was causing us to vmenter with invalid segments;
this message would have been very misleading in that case. I think you'd have to do
more complete analysis of the vmentry failure code to be more certain about the reason
for failure.
We should probably only display this message if reason == 0x80000021.
It may be worth looking at the cpu_state to verify that we're trying to
enter 16-bit mode too.
Then the message can be much more definitive too.
Regards,
Anthony Liguori
--
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
