On Fri, Jun 13, 2008 at 2:33 PM, Mohammed Gamal <m.gamal005@xxxxxxxxx> wrote: > On Tue, Jun 10, 2008 at 4:46 PM, Glauber Costa <gcosta@xxxxxxxxxx> wrote: >> If we're not gonna do anything (case in which failure is already >> reported), we do not need to even bother with calculating the linear rip. >> >> This is a nitpick, but I saw it while doing some testing, so here's >> the patch. >> >> Signed-off-by: Glauber Costa <gcosta@xxxxxxxxxx> >> --- >> arch/x86/kvm/x86.c | 4 ++-- >> 1 files changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c >> index 77fb2bd..191fef1 100644 >> --- a/arch/x86/kvm/x86.c >> +++ b/arch/x86/kvm/x86.c >> @@ -2026,11 +2026,11 @@ void kvm_report_emulation_failure(struct kvm_vcpu *vcpu, const char *context) >> unsigned long rip = vcpu->arch.rip; >> unsigned long rip_linear; >> >> - rip_linear = rip + get_segment_base(vcpu, VCPU_SREG_CS); >> - >> if (reported) >> return; >> >> + rip_linear = rip + get_segment_base(vcpu, VCPU_SREG_CS); >> + >> emulator_read_std(rip_linear, (void *)opcodes, 4, vcpu); >> >> printk(KERN_ERR "emulation failed (%s) rip %lx %02x %02x %02x %02x\n", >> -- >> 1.5.4.5 > > Why return immediately? Shouldn't we report on failure whenever it > occurs (i.e. by rather removing the if condition)? > the kernel ring buffer would be full very quickly, and this is not a strong enough reason to do that ;-) Most of the messages would be the same. What I do think would be useful, and even planned to do (just have more priority things waiting), is to move the checking field to the vcpu struct. With the current setup, if you kill your guest, set things up again, and run it, you won't see any messages, even if it fails. So the warning should really be once in the lifetime of the virtual machine, not once in the lifetime of the kvm module. -- Glauber Costa. "Free as in Freedom" http://glommer.net "The less confident you are, the more serious you have to act." _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/virtualization
