From 45adec566b073b39f4edfc1307843d12fe8105c8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= <berrange@redhat.com>
Date: Tue, 31 Aug 2021 18:50:33 +0100
Subject: [PATCH 1/2] target/i386: add missing bits to CR4_RESERVED_MASK
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Booting Fedora kernels with -cpu max hangs very early in boot. Disabling
the la57 CPUID bit fixes the problem. git bisect traced the regression to

  commit 213ff024a2f92020290296cb9dc29c2af3d4a221 (HEAD, refs/bisect/bad)
  Author: Lara Lazier <laramglazier@gmail.com>
  Date:   Wed Jul 21 17:26:50 2021 +0200

    target/i386: Added consistency checks for CR4

    All MBZ bits in CR4 must be zero. (APM2 15.5)
    Added reserved bitmask and added checks in both
    helper_vmrun and helper_write_crN.

    Signed-off-by: Lara Lazier <laramglazier@gmail.com>
    Message-Id: <20210721152651.14683-2-laramglazier@gmail.com>
    Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

In this commit CR4_RESERVED_MASK is missing CR4_LA57_MASK and
two others. Adding this lets Fedora kernels boot once again.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
 target/i386/cpu.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index 6c50d3ab4f..ce85f1a29d 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -257,6 +257,7 @@ typedef enum X86Seg {
                 | CR4_DE_MASK | CR4_PSE_MASK | CR4_PAE_MASK \
                 | CR4_MCE_MASK | CR4_PGE_MASK | CR4_PCE_MASK \
                 | CR4_OSFXSR_MASK | CR4_OSXMMEXCPT_MASK |CR4_UMIP_MASK \
+                | CR4_LA57_MASK | CR4_VMXE_MASK | CR4_SMXE_MASK \
                 | CR4_FSGSBASE_MASK | CR4_PCIDE_MASK | CR4_OSXSAVE_MASK \
                 | CR4_SMEP_MASK | CR4_SMAP_MASK | CR4_PKE_MASK | CR4_PKS_MASK))
 
-- 
2.32.0