Bug#1017944: Also affects PVH DomUs

[Thomas Keppler]

Severity: grave

I have just confirmed that this bug also seems to affect PVH DomUs, failing with:

root at hypervisor:~# xl dmesg -c
(XEN) MMIO emulation failed (1): d69v0 32bit @ 0000:3fffffff -> 00
(XEN) d69v0 Triple fault - invoking HVM shutdown action 1
(XEN) *** Dumping Dom69 vcpu#0 state: ***
(XEN) ----[ Xen-4.14.5  x86_64  debug=n   Not tainted ]----
(XEN) CPU:    3
(XEN) RIP:    0000:[<000000003fffffff>]
(XEN) RFLAGS: 0000000000010083   CONTEXT: hvm guest (d69v0)
(XEN) rax: 00000000000061d6   rbx: 0000000000126000   rcx: 0000000000000000
(XEN) rdx: 0000000000000000   rsi: 0000000000000001   rdi: 0000000000000000
(XEN) rbp: 0000000000000000   rsp: 0000000000000000   r8:  0000000000000000
(XEN) r9:  0000000000000000   r10: 0000000000000000   r11: 0000000000000000
(XEN) r12: 0000000000000000   r13: 0000000000000000   r14: 0000000000000000
(XEN) r15: 0000000000000000   cr0: 0000000000000011   cr4: 0000000000000000
(XEN) cr3: 0000000000000000   cr2: 0000000000000000
(XEN) fsb: 0000000000000000   gsb: 0000000000000000   gss: 0000000000000000
(XEN) ds: 0000   es: 0000   fs: 0000   gs: 0000   ss: 0000   cs: 0000
(XEN) MMIO emulation failed (1): d70v0 32bit @ 0000:3fffffff -> 00
(XEN) d70v0 Triple fault - invoking HVM shutdown action 1
(XEN) *** Dumping Dom70 vcpu#0 state: ***
(XEN) ----[ Xen-4.14.5  x86_64  debug=n   Not tainted ]----
(XEN) CPU:    1
(XEN) RIP:    0000:[<000000003fffffff>]
(XEN) RFLAGS: 0000000000010083   CONTEXT: hvm guest (d70v0)
(XEN) rax: 00000000000061d6   rbx: 0000000000126000   rcx: 0000000000000000
(XEN) rdx: 0000000000000000   rsi: 0000000000000001   rdi: 0000000000000000
(XEN) rbp: 0000000000000000   rsp: 0000000000000000   r8:  0000000000000000
(XEN) r9:  0000000000000000   r10: 0000000000000000   r11: 0000000000000000
(XEN) r12: 0000000000000000   r13: 0000000000000000   r14: 0000000000000000
(XEN) r15: 0000000000000000   cr0: 0000000000000011   cr4: 0000000000000000
(XEN) cr3: 0000000000000000   cr2: 0000000000000000
(XEN) fsb: 0000000000000000   gsb: 0000000000000000   gss: 0000000000000000
(XEN) ds: 0000   es: 0000   fs: 0000   gs: 0000   ss: 0000   cs: 0000

This is the config I used:

name = "test"
vcpus = "1"
memory = "2048"
vif = [
"bridge=lanbr",
]
disk = [
"phy:/dev/vg0/test,xvda1,w",
"phy:/dev/vg0/test-swap,xvdb1,w",
]
#kernel = "/usr/lib/grub-xen/grub-x86_64-xen.bin"
type = "pvh"
pvhshim = 1
kernel = "/usr/lib/grub-xen/grub-i386-xen_pvh.bin"

As you can see, this is a relatively simple configuration which works fine with 2.04-20.

Since PVH domains are the current norm and are also affected, I propose to mark this as "grave" at least.

HVM DomUs work fine, however, since they don't rely on this mechanism at all (as would be expected).