From 6d1bc9754b04075d938b47cf7f7800814b8911a7 Mon Sep 17 00:00:00 2001 From: Alexander Mikhalitsyn Date: Mon, 22 May 2023 18:12:48 +0200 Subject: [PATCH] KVM: SVM: enhance info printk's in SEV init MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Let's print available ASID ranges for SEV/SEV-ES guests. This information can be useful for system administrator to debug if SEV/SEV-ES fails to enable. There are a few reasons. SEV: - NPT is disabled (module parameter) - CPU lacks some features (sev, decodeassists) - Maximum SEV ASID is 0 SEV-ES: - mmio_caching is disabled (module parameter) - CPU lacks sev_es feature - Minimum SEV ASID value is 1 (can be adjusted in BIOS/UEFI) Cc: Sean Christopherson Cc: Paolo Bonzini Cc: Stéphane Graber Cc: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Suggested-by: Sean Christopherson Signed-off-by: Alexander Mikhalitsyn Link: https://lore.kernel.org/r/20230522161249.800829-3-aleksandr.mikhalitsyn@canonical.com [sean: print '0' for min SEV-ES ASID if there are no available ASIDs] Signed-off-by: Sean Christopherson --- arch/x86/kvm/svm/sev.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 69ae5e1..d65578d 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -2219,7 +2219,6 @@ void __init sev_hardware_setup(void) if (misc_cg_set_capacity(MISC_CG_RES_SEV, sev_asid_count)) goto out; - pr_info("SEV supported: %u ASIDs\n", sev_asid_count); sev_supported = true; /* SEV-ES support requested? */ @@ -2247,10 +2246,18 @@ void __init sev_hardware_setup(void) if (misc_cg_set_capacity(MISC_CG_RES_SEV_ES, sev_es_asid_count)) goto out; - pr_info("SEV-ES supported: %u ASIDs\n", sev_es_asid_count); sev_es_supported = true; out: + if (boot_cpu_has(X86_FEATURE_SEV)) + pr_info("SEV %s (ASIDs %u - %u)\n", + sev_supported ? "enabled" : "disabled", + min_sev_asid, max_sev_asid); + if (boot_cpu_has(X86_FEATURE_SEV_ES)) + pr_info("SEV-ES %s (ASIDs %u - %u)\n", + sev_es_supported ? "enabled" : "disabled", + min_sev_asid > 1 ? 1 : 0, min_sev_asid - 1); + sev_enabled = sev_supported; sev_es_enabled = sev_es_supported; #endif -- 2.7.4