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 <laramglaz...@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 <laramglaz...@gmail.com>
Message-Id: <20210721152651.14683-2-laramglaz...@gmail.com>
Signed-off-by: Paolo Bonzini <pbonz...@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 <berra...@redhat.com>
---
target/i386/cpu.h | 1 +
1 file changed, 1 insertion(+)
I don't know the implications of CR4_VMXE_MASK and CR4_SMXE_MASK
being missing in CR4_RESERVED_MASK. It didn't cause any ill effects
either way, but I added them on the assumption that CR4_RESERVED_MASK
was supposed to contain all define bits.
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))
--
2.31.1
