On 12.11.2025 21:25, Grygorii Strashko wrote: > Could it be merged if no other comments, please?
It's on my list of things to put in. However, since you ask: You do realize that all your recent postings were while the tree was frozen? That's okay-ish, but when preparing a release people would preferably focus on the release, not on what is to come afterwards. This change of yours, like quite a few from others, will need to wait until the tree is fully open again. It having been progressed to the point where it can in principle go in was already a courtesy, considering the timing. Jan > On 24.09.25 13:14, Grygorii Strashko wrote: >> From: Grygorii Strashko <[email protected]> >> >> Since commit b99227347230 ("x86: Fix AMD_SVM and INTEL_VMX dependency") the >> HVM Intel VT-x support can be disabled, but it still keeps VMX >> code partially built-in. Particularly in HVM code there are two places: >> >> 1) hvm/dom0_build.c >> dom0_construct_pvh()->pvh_populate_p2m() >> ... >> if ( cpu_has_vmx && paging_mode_hap(d) && !vmx_unrestricted_guest(v) ) >> { >> ... >> [unreachable for !cpu_has_vmx case] >> rc = pvh_setup_vmx_realmode_helpers(d); >> >> pvh_setup_vmx_realmode_helpers() allocates memory and configures >> HVM_PARAM_VM86_TSS_SIZED >> HVM_PARAM_IDENT_PT >> >> 2) hvm/hvm.c >> hvm_set_param() >> ... >> case HVM_PARAM_IDENT_PT: >> >> if ( !paging_mode_hap(d) || !cpu_has_vmx ) >> { >> d->arch.hvm.params[index] = value; >> break; >> } >> [unreachable for !cpu_has_vmx case] >> ... >> >> Hence HVM_PARAM_IDENT_PT/HVM_PARAM_VM86_TSS_SIZED are used only by VMX code >> above code become unreachable in !cpu_has_vmx case and can be optimazed >> when !CONFIG_INTEL_VMX. >> >> Replace "cpu_has_vmx" with using_vmx() to account !CONFIG_INTEL_VMX and allow >> compiler DCE to optimize code. >> >> Signed-off-by: Grygorii Strashko <[email protected]> >> --- >> add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-604 (-604) >> Function old new delta >> hvm_set_param 1602 1473 -129 >> dom0_construct_pvh 4438 3963 -475 >> Total: Before=3567191, After=3566587, chg -0.02% >> >> xen/arch/x86/hvm/dom0_build.c | 2 +- >> xen/arch/x86/hvm/hvm.c | 2 +- >> 2 files changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/xen/arch/x86/hvm/dom0_build.c b/xen/arch/x86/hvm/dom0_build.c >> index 5551f9044836..5ac2cf8394d8 100644 >> --- a/xen/arch/x86/hvm/dom0_build.c >> +++ b/xen/arch/x86/hvm/dom0_build.c >> @@ -473,7 +473,7 @@ static int __init pvh_populate_p2m(struct domain *d) >> } >> } >> >> - if ( cpu_has_vmx && paging_mode_hap(d) && !vmx_unrestricted_guest(v) ) >> + if ( using_vmx() && paging_mode_hap(d) && !vmx_unrestricted_guest(v) ) >> { >> /* >> * Since Dom0 cannot be migrated, we will only setup the >> diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c >> index 95a80369b9b8..70331aeec9a0 100644 >> --- a/xen/arch/x86/hvm/hvm.c >> +++ b/xen/arch/x86/hvm/hvm.c >> @@ -4302,7 +4302,7 @@ static int hvm_set_param(struct domain *d, uint32_t >> index, uint64_t value) >> * Only actually required for VT-x lacking unrestricted_guest >> * capabilities. Short circuit the pause if possible. >> */ >> - if ( !paging_mode_hap(d) || !cpu_has_vmx ) >> + if ( !paging_mode_hap(d) || !using_vmx() ) >> { >> d->arch.hvm.params[index] = value; >> break; >
