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[qemu-xen staging-4.16] target/i386: add missing bits to CR4_RESERVED_MASK



commit e88636b4d46b91e130ae715b8d8b90f62e414428
Author:     Daniel P. Berrangé <berrange@xxxxxxxxxx>
AuthorDate: Tue Aug 31 18:50:33 2021 +0100
Commit:     Michael Roth <michael.roth@xxxxxxx>
CommitDate: Wed Dec 15 07:13:18 2021 -0600

    target/i386: add missing bits to CR4_RESERVED_MASK
    
    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@xxxxxxxxx>
      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@xxxxxxxxx>
        Message-Id: <20210721152651.14683-2-laramglazier@xxxxxxxxx>
        Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
    
    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@xxxxxxxxxx>
    Tested-by: Richard W.M. Jones <rjones@xxxxxxxxxx>
    Message-Id: <20210831175033.175584-1-berrange@xxxxxxxxxx>
    [Removed VMXE/SMXE, matching the commit message. - Paolo]
    Fixes: 213ff024a2 ("target/i386: Added consistency checks for CR4", 
2021-07-22)
    Cc: qemu-stable@xxxxxxxxxx
    Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
    (cherry picked from commit 69e3895f9d37ca39536775b13ce63e8c291427ba)
    Signed-off-by: Michael Roth <michael.roth@xxxxxxx>
---
 target/i386/cpu.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index 6c50d3ab4f..21b33fbe2e 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_FSGSBASE_MASK | CR4_PCIDE_MASK | CR4_OSXSAVE_MASK \
                 | CR4_SMEP_MASK | CR4_SMAP_MASK | CR4_PKE_MASK | CR4_PKS_MASK))
 
--
generated by git-patchbot for /home/xen/git/qemu-xen.git#staging-4.16



 


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