[Qemu-devel] support using KVM_MEM_READONLY flag for regions commit and OVMF UEFI incompatibility

[Oleksii Shevchuk]

I tried do run QEMU with OVMF UEFI bios (QEMU and EDK2 trunk). It hangs
while booting:

qemu-kvm -L . -bios OVMF.fd --enable-kvm -debugcon file:/tmp/debug
 -global isa-debugcon.iobase=0x402 -global PIIX4_PM.disable_s3=0 -global
 PIIX4_PM.disable_s4=0

SecCoreStartupWithStack(0xFFFE6000, 0x80000)
File->Type: 0xB
Section->Type: 0x2
Section->Type: 0x19
Section->Type (0x19) != SectionType (0x17)
Section->Type: 0x17
File->Type: 0x2
File->Type (0x2) != FileType (0x4)
File->Type: 0xF0
File->Type (0xF0) != FileType (0x4)
File->Type: 0x4
Section->Type: 0x19
Section->Type (0x19) != SectionType (0x10)
Section->Type: 0x10
Register PPI Notify: DCD0BE23-9586-40F4-B643-06522CED4EDE
Install PPI: 8C8CE578-8A3D-4F1C-9935-896185C32DD3
Install PPI: 5473C07A-3DCB-4DCA-BD6F-1E9689E7349A
The 0th FV start address is 0x00000800000, size is 0x00800000, handle is 
0x800000
Register PPI Notify: 49EDB1C1-BF21-4761-BB12-EB0031AABB39
Install PPI: B9E0ABFE-5979-4914-977F-6DEE78C278A6
Install PPI: DBE23AA9-A345-4B97-85B6-B226F1617389
Loading PEIM at 0x00000815220 EntryPoint=0x00000815480 PcdPeim.efi
Install PPI: 06E81C58-4AD7-44BC-8390-F10265F72480
Install PPI: 01F34D25-4DE2-23AD-3FF3-36353FF323F1
Loading PEIM at 0x0000081C920 EntryPoint=0x0000081CB80 StatusCodePei.efi
Install PPI: 229832D3-7A30-4B36-B827-F40CB7D45436
Loading PEIM at 0x00000822220 EntryPoint=0x00000822480 PlatformPei.efi
Platform PEIM Loaded
CMOS:
00:%                                                                            
                                                            

> strace -e open qemu-kvm -L . -bios OVMF.fd --enable-kvm -debugcon
> file:/tmp/debug -global isa-debugcon.iobase=0x402 -global
> PIIX4_PM.disable_s3=0 -global PIIX4_PM.disable_s4=0 2>&1 | grep bin
open("/usr/bin/qemu-kvm", O_RDONLY)     = 3
open("/usr/share/qemu/kvmvapic.bin", O_RDONLY) = 11
open("/usr/share/qemu/vgabios-cirrus.bin", O_RDONLY) = 11
open("/usr/share/qemu/vgabios-cirrus.bin", O_RDONLY) = 11

> file -L "/usr/share/qemu/vgabios-cirrus.bin" 
/usr/share/qemu/vgabios-cirrus.bin: BIOS (ia32) ROM Ext. IBM comp. Video 
(71*512)

I managed to run it without KVM, while it successfully runnings with KVM in 
qemu 1.4.2.
Bisecting showed, that regression introduced with commit
235e8982ad393e5611cb892df54881c872eea9e1: 

Author: Jordan Justen <address@hidden>
Date:   Wed May 29 01:27:26 2013 -0700

    kvm: support using KVM_MEM_READONLY flag for regions
    
    For readonly memory regions and rom devices in romd_mode,
    we make use of the KVM_MEM_READONLY. A slot that uses
    KVM_MEM_READONLY can be read from and code can execute from the
    region, but writes will exit to qemu.
    
    For rom devices with !romd_mode, we force the slot to be
    removed so reads or writes to the region will exit to qemu.
    (Note that a memory region in this state is not executable
    within kvm.)
    
    v7:
     * Update for readable => romd_mode rename (5f9a5ea1)
    
    Signed-off-by: Jordan Justen <address@hidden>
    Reviewed-by: Xiao Guangrong <address@hidden> (v4)
    Reviewed-by: Paolo Bonzini <address@hidden> (v5)
    Message-id: address@hidden
    Signed-off-by: Anthony Liguori <address@hidden>

:100644 100644 327ae12f08b9dddc796d753d8adfb1f70c78b2c1 
8e7bbf8698f6bcaa5ae945ef86e7b51effde06fe M      kvm-all.c