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Date:   Tue, 22 Feb 2022 21:22:01 -0800
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Subject: [RFC PATCH 25/47] mm: asi: Avoid warning from NMI userspace accesses
 in ASI context
From:   Junaid Shahid <junaids@google.com>
To:     linux-kernel@vger.kernel.org
Cc:     kvm@vger.kernel.org, pbonzini@redhat.com, jmattson@google.com,
        pjt@google.com, oweisse@google.com, alexandre.chartre@oracle.com,
        rppt@linux.ibm.com, dave.hansen@linux.intel.com,
        peterz@infradead.org, tglx@linutronix.de, luto@kernel.org,
        linux-mm@kvack.org
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nmi_uaccess_okay() emits a warning if current CR3 != mm->pgd.
Limit the warning to only when ASI is not active.

Signed-off-by: Junaid Shahid <junaids@google.com>


---
 arch/x86/mm/tlb.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c
index 25bee959d1d3..628f1cd904ac 100644
--- a/arch/x86/mm/tlb.c
+++ b/arch/x86/mm/tlb.c
@@ -1292,7 +1292,8 @@ bool nmi_uaccess_okay(void)
 	if (loaded_mm != current_mm)
 		return false;
 
-	VM_WARN_ON_ONCE(current_mm->pgd != __va(read_cr3_pa()));
+	VM_WARN_ON_ONCE(current_mm->pgd != __va(read_cr3_pa()) &&
+			!is_asi_active());
 
 	return true;
 }
-- 
2.35.1.473.g83b2b277ed-goog