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

[Hannes Reinecke]

On 07/15/2013 03:21 PM, Oleksii Shevchuk wrote:
> 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
Confirmed.

Reverting the mentioned commit makes everything run smoothly again.

Cheers,

Hannes