| Message ID | f7d395b60eb7e6dcc149ba39d86f9296bd81b0ac.1658913543.git.houwenlong.hwl@antgroup.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add missing trace points in emulator path | expand |
On Thu, Jul 28, 2022, Hou Wenlong wrote: > Since the RDMSR/WRMSR emulation uses a sepearte emualtor interface, > the trace points for RDMSR/WRMSR can be added in emulator path like > normal path. > > Signed-off-by: Hou Wenlong <houwenlong.hwl@antgroup.com> > --- > arch/x86/kvm/x86.c | 20 ++++++++++++++------ > 1 file changed, 14 insertions(+), 6 deletions(-) > > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index 8df89b9c212f..6e45b20ce9a4 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -7908,12 +7908,16 @@ static int emulator_get_msr_with_filter(struct x86_emulate_ctxt *ctxt, > int r; > > r = kvm_get_msr_with_filter(vcpu, msr_index, pdata); > - if (r) { > + if (!r) { > + trace_kvm_msr_read(msr_index, *pdata); > + } else { > if (kvm_msr_user_space(vcpu, msr_index, KVM_EXIT_X86_RDMSR, 0, > - complete_emulated_rdmsr, r)) > + complete_emulated_rdmsr, r)) { > r = X86EMUL_IO_NEEDED; > - else > + } else { > + trace_kvm_msr_read_ex(msr_index); Drat, I suspected this patch would make adding a helper a mess. We could use trace_kvm_msr() directly, using @exit_reason to select between "rdmsr" and "wrmsr", but I think the end result is less readable and not worth the small amount of deduplication. E.g. this is rather hard to read. if (r < 0) return X86EMUL_UNHANDLEABLE; if (r) { if (kvm_msr_user_space(vcpu, msr, exit_reason, data, comp, r)) return X86EMUL_IO_NEEDED; trace_kvm_msr(exit_reason == KVM_EXIT_X86_WRMSR, msr, data, true); return X86EMUL_PROPAGATE_FAULT; } trace_kvm_msr(exit_reason == KVM_EXIT_X86_WRMSR, msr, data, false); return X86EMUL_CONTINUE; Aha! If there "error" paths return directly, then the "else" paths go away and this is all (IMO) a bit cleaner. And the diff for this patch should be much smaller since there won't be any curly brace changes. How about this for a final product? static int emulator_get_msr_with_filter(struct x86_emulate_ctxt *ctxt, u32 msr_index, u64 *pdata) { struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt); int r; r = kvm_get_msr_with_filter(vcpu, msr_index, pdata); if (r < 0) return X86EMUL_UNHANDLEABLE; if (r) { if (kvm_msr_user_space(vcpu, msr_index, KVM_EXIT_X86_RDMSR, 0, complete_emulated_rdmsr, r)) return X86EMUL_IO_NEEDED; trace_kvm_msr_read_ex(msr_index); return X86EMUL_PROPAGATE_FAULT; } trace_kvm_msr_read(msr_index, *pdata); return X86EMUL_CONTINUE; } static int emulator_set_msr_with_filter(struct x86_emulate_ctxt *ctxt, u32 msr_index, u64 data) { struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt); int r; r = kvm_set_msr_with_filter(vcpu, msr_index, data); if (r < 0) return X86EMUL_UNHANDLEABLE; if (r) { if (kvm_msr_user_space(vcpu, msr_index, KVM_EXIT_X86_WRMSR, data, complete_emulated_msr_access, r)) return X86EMUL_IO_NEEDED; trace_kvm_msr_write_ex(msr_index, data); return X86EMUL_PROPAGATE_FAULT; } trace_kvm_msr_write(msr_index, data); return X86EMUL_CONTINUE; }
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 8df89b9c212f..6e45b20ce9a4 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -7908,12 +7908,16 @@ static int emulator_get_msr_with_filter(struct x86_emulate_ctxt *ctxt, int r; r = kvm_get_msr_with_filter(vcpu, msr_index, pdata); - if (r) { + if (!r) { + trace_kvm_msr_read(msr_index, *pdata); + } else { if (kvm_msr_user_space(vcpu, msr_index, KVM_EXIT_X86_RDMSR, 0, - complete_emulated_rdmsr, r)) + complete_emulated_rdmsr, r)) { r = X86EMUL_IO_NEEDED; - else + } else { + trace_kvm_msr_read_ex(msr_index); r = X86EMUL_UNHANDLEABLE; + } } return r; @@ -7926,12 +7930,16 @@ static int emulator_set_msr_with_filter(struct x86_emulate_ctxt *ctxt, int r; r = kvm_set_msr_with_filter(vcpu, msr_index, data); - if (r > 0) { + if (!r) { + trace_kvm_msr_write(msr_index, data); + } else if (r > 0) { if (kvm_msr_user_space(vcpu, msr_index, KVM_EXIT_X86_WRMSR, data, - complete_emulated_msr_access, r)) + complete_emulated_msr_access, r)) { r = X86EMUL_IO_NEEDED; - else + } else { + trace_kvm_msr_write_ex(msr_index, data); r = X86EMUL_UNHANDLEABLE; + } } return r;
Since the RDMSR/WRMSR emulation uses a sepearte emualtor interface, the trace points for RDMSR/WRMSR can be added in emulator path like normal path. Signed-off-by: Hou Wenlong <houwenlong.hwl@antgroup.com> --- arch/x86/kvm/x86.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-)