Kernel KVM virtualization development
 help / color / mirror / Atom feed
From: Sean Christopherson <seanjc@google.com>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: kvm@vger.kernel.org, Sean Christopherson <seanjc@google.com>,
	 Mathias Krause <minipli@grsecurity.net>,
	Andrew Jones <andrew.jones@linux.dev>
Subject: [kvm-unit-tests PATCH v3 08/20] x86/vmx: Use separate VMCSes for BSP vs. AP in INIT test
Date: Thu, 14 May 2026 14:04:48 -0700	[thread overview]
Message-ID: <20260514210500.1626871-9-seanjc@google.com> (raw)
In-Reply-To: <20260514210500.1626871-1-seanjc@google.com>

Allocate and use a separate VMCS for the AP CPU in VMX's INIT test, and
simply mark the guest as finished on the BSP.  Sharing a VMCS between CPUs
requires _more_ code than allocating a dedicated VMCS, and completely
falls apart if things like "launched" are made per-CPU (spoiler alert).

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 x86/vmx_tests.c | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/x86/vmx_tests.c b/x86/vmx_tests.c
index e2bf06ac..effd0c59 100644
--- a/x86/vmx_tests.c
+++ b/x86/vmx_tests.c
@@ -9976,7 +9976,8 @@ static bool init_signal_test_thread_continued;
 
 static void init_signal_test_thread(void *data)
 {
-	struct vmcs *test_vmcs = data;
+	struct guest_regs *regs = this_cpu_guest_regs();
+	struct vmcs *ap_vmcs;
 
 	/* Enter VMX operation (i.e. exec VMXON) */
 	u64 *ap_vmxon_region = alloc_page();
@@ -9984,6 +9985,11 @@ static void init_signal_test_thread(void *data)
 	init_vmx(ap_vmxon_region);
 	TEST_ASSERT(!__vmxon_safe(ap_vmxon_region));
 
+	init_vmcs(&ap_vmcs);
+	make_vmcs_current(ap_vmcs);
+
+	memset(regs, 0, sizeof(regs));
+
 	/* Signal CPU have entered VMX operation */
 	vmx_set_test_stage(1);
 
@@ -10003,13 +10009,10 @@ static void init_signal_test_thread(void *data)
 
 	/* Enter VMX non-root mode */
 	test_set_guest(v2_null_test_guest);
-	make_vmcs_current(test_vmcs);
 	enter_guest();
 	/* Save exit reason for BSP CPU to compare to expected result */
 	init_signal_test_exit_reason = vmcs_read(EXI_REASON);
-	/* VMCLEAR test-vmcs so it could be loaded by BSP CPU */
-	vmcs_clear(test_vmcs);
-	launched = false;
+
 	/* Signal that CPU exited to VMX root mode */
 	vmx_set_test_stage(5);
 
@@ -10110,9 +10113,8 @@ static void vmx_init_signal_test(void)
 			exit_reason_description(init_signal_test_exit_reason),
 			init_signal_test_exit_reason);
 
-	/* Run guest to completion */
-	make_vmcs_current(test_vmcs);
-	enter_guest();
+	/* Mark the guest as being done. */
+	test_set_guest_finished();
 
 	/* Signal other CPU to exit VMX operation */
 	init_signal_test_thread_continued = false;
-- 
2.54.0.563.g4f69b47b94-goog


  parent reply	other threads:[~2026-05-14 21:05 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-05-14 21:04 [kvm-unit-tests PATCH v3 00/20] x86: Better backtraces for leaf functions Sean Christopherson
2026-05-14 21:04 ` [kvm-unit-tests PATCH v3 01/20] x86/vmx: Drop unused SYSENTER "support" in nested VMX infrastructure Sean Christopherson
2026-05-14 21:04 ` [kvm-unit-tests PATCH v3 02/20] x86/vmx: Drop unused guest_regs " Sean Christopherson
2026-05-14 21:04 ` [kvm-unit-tests PATCH v3 03/20] x86/svm: Sort (and swap) GPRs by their index, not alphabetically Sean Christopherson
2026-05-14 21:04 ` [kvm-unit-tests PATCH v3 04/20] x86: Dedup guest/host context switch of registers across SVM and VMX Sean Christopherson
2026-05-14 21:04 ` [kvm-unit-tests PATCH v3 05/20] x86/virt: Use macro shenanigans to get reg offsets when swapping guest/host regs Sean Christopherson
2026-05-14 21:04 ` [kvm-unit-tests PATCH v3 06/20] x86/virt: Track "guest regs" using per-CPU variable Sean Christopherson
2026-05-14 21:04 ` [kvm-unit-tests PATCH v3 07/20] x86/svm: Don't VMLOAD/VMSAVE "guest" state around VMRUN Sean Christopherson
2026-05-14 21:04 ` Sean Christopherson [this message]
2026-05-14 21:04 ` [kvm-unit-tests PATCH v3 09/20] x86/vmx: Swap GPRs after checking "launched" status Sean Christopherson
2026-05-14 21:04 ` [kvm-unit-tests PATCH v3 10/20] x86/vmx: Track VMCS "launched" state per-CPU Sean Christopherson
2026-05-14 21:04 ` [kvm-unit-tests PATCH v3 11/20] x86/vmx: Track "is this CPU in guest mode" per-CPU Sean Christopherson
2026-05-14 21:04 ` [kvm-unit-tests PATCH v3 12/20] x86/vmx: Communicate hypercalls via RAX, not a global field Sean Christopherson
2026-05-14 21:04 ` [kvm-unit-tests PATCH v3 13/20] x86/vmx: Initialize test stage in SIPI test *before* launching AP thread Sean Christopherson
2026-05-14 21:04 ` [kvm-unit-tests PATCH v3 14/20] x86/kvmclock: Replace spaces with tabs Sean Christopherson
2026-05-14 21:04 ` [kvm-unit-tests PATCH v3 15/20] x86/kvmclock: Skip kvmclock test when not running on KVM with CLOCKSOURCE2 Sean Christopherson
2026-05-14 21:04 ` [kvm-unit-tests PATCH v3 16/20] x86/vmx: Tag "struct vmx_msr_entry" as needing to be 16-byte aligned Sean Christopherson
2026-05-14 21:04 ` [kvm-unit-tests PATCH v3 17/20] x86/smp: Align the stack to a 16-byte boundary when invoking SMP function calls Sean Christopherson
2026-05-14 21:04 ` [kvm-unit-tests PATCH v3 18/20] x86/vmx: Write to KVM's WALL_CLOCK MSR via VM-Entry load list sync in SIPI test Sean Christopherson
2026-05-14 21:04 ` [kvm-unit-tests PATCH v3 19/20] x86: Better backtraces for leaf functions Sean Christopherson
2026-05-14 21:05 ` [kvm-unit-tests PATCH v3 20/20] x86: Prevent realmode test code instrumentation with nop-mcount Sean Christopherson

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20260514210500.1626871-9-seanjc@google.com \
    --to=seanjc@google.com \
    --cc=andrew.jones@linux.dev \
    --cc=kvm@vger.kernel.org \
    --cc=minipli@grsecurity.net \
    --cc=pbonzini@redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox