Re: [RFC PATCH 08/10] connect vmport up

[Boris Ostrovsky <boris.ostrovsky@oracle.com>]

On 12/12/2013 02:15 PM, Don Slutz wrote:
> From: Don Slutz <dslutz@verizon.com>
>
> Signed-off-by: Don Slutz <dslutz@verizon.com>
> ---
>   xen/arch/x86/hvm/io.c       |   4 ++
>   xen/arch/x86/hvm/svm/svm.c  | 104 ++++++++++++++++++++++++++++++++++++
>   xen/arch/x86/hvm/svm/vmcb.c |   1 +
>   xen/arch/x86/hvm/vmx/vmcs.c |   1 +
>   xen/arch/x86/hvm/vmx/vmx.c  | 125 ++++++++++++++++++++++++++++++++++++++++++++
>   xen/arch/x86/hvm/vmx/vvmx.c |  13 +++++
>   xen/include/public/trace.h  |   1 +
>   7 files changed, 249 insertions(+)
>
> diff --git a/xen/arch/x86/hvm/io.c b/xen/arch/x86/hvm/io.c
> index bf6309d..4bc4716 100644
> --- a/xen/arch/x86/hvm/io.c
> +++ b/xen/arch/x86/hvm/io.c
> @@ -42,6 +42,7 @@
>   #include <asm/hvm/vlapic.h>
>   #include <asm/hvm/trace.h>
>   #include <asm/hvm/emulate.h>
> +#include <asm/hvm/vmport.h>
>   #include <public/sched.h>
>   #include <xen/iocap.h>
>   #include <public/hvm/ioreq.h>
> @@ -236,6 +237,9 @@ int handle_pio(uint16_t port, unsigned int size, int dir)
>       if ( dir == IOREQ_WRITE )
>           data = guest_cpu_user_regs()->eax;
>   
> +    if ( port == VMPORT_PORT )
> +        return vmport_ioport(dir, size, data, guest_cpu_user_regs());
> +
>       rc = hvmemul_do_pio(port, &reps, size, 0, dir, 0, &data);
>   
>       switch ( rc )
> diff --git a/xen/arch/x86/hvm/svm/svm.c b/xen/arch/x86/hvm/svm/svm.c
> index 406d394..80cf2bf 100644
> --- a/xen/arch/x86/hvm/svm/svm.c
> +++ b/xen/arch/x86/hvm/svm/svm.c
> @@ -56,6 +56,7 @@
>   #include <asm/hvm/svm/nestedsvm.h>
>   #include <asm/hvm/nestedhvm.h>
>   #include <asm/x86_emulate.h>
> +#include <asm/hvm/vmport.h>
>   #include <public/sched.h>
>   #include <asm/hvm/vpt.h>
>   #include <asm/hvm/trace.h>
> @@ -1904,6 +1905,105 @@ svm_vmexit_do_vmsave(struct vmcb_struct *vmcb,
>       return;
>   }
>   
> +static void svm_vmexit_gp_intercept(struct cpu_user_regs *regs, struct vcpu *v)
> +{
> +    struct hvm_domain *hd = &v->domain->arch.hvm_domain;
> +    struct vmcb_struct *vmcb = v->arch.hvm_svm.vmcb;
> +    unsigned long inst_len, bytes_len;
> +    int frc;
> +    unsigned char bytes[15];
> +
> +    regs->error_code = vmcb->exitinfo1;
> +    if ( !cpu_has_svm_nrips || (vmcb->nextrip <= vmcb->rip) )
> +        inst_len = 0;
> +    else
> +        inst_len = vmcb->nextrip - vmcb->rip;

You can use svm_nextrip_insn_length(), with some adjustments to NDEBUG 
case there.

> +    bytes_len = 2 /* inst_len < 15 ? inst_len > 1 ? inst_len : 2 : 15 */;

Saying this in words would be preferable --- I am not sure I understand 
why it's 2. Do you only expect specific instructions here? Or are you 
only interested in the first two bytes of the opcode?

> +    frc = hvm_fetch_from_guest_virt_nofault(bytes, regs->eip,
> +                                            bytes_len,
> +                                            PFEC_page_present);
> +
> +    if ( hvm_long_mode_enabled(v) )
> +        HVMTRACE_LONG_4D(TRAP, TRAP_gp_fault, inst_len,
> +                         regs->error_code,
> +                         TRC_PAR_LONG(vmcb->exitinfo2) );
> +    else
> +        HVMTRACE_4D(TRAP, TRAP_gp_fault, inst_len,
> +                    regs->error_code, vmcb->exitinfo2 );
> +
> +    if (hd->params[HVM_PARAM_VMPORT_LOGMASK] & 0x400000 /* LOG_GP_FAIL_RD_INST */)
> +        printk("[HVM:%d.%d] <%s> "
> +               "gp: e2=%lx ec=%lx ip=%lx=>0x%x 0x%x(%ld,%ld,%d) nip(%d)=%lx(%d,%d(0x%x) 0x%x 0x%x)"
> +               "\n",
> +               current->domain->domain_id, current->vcpu_id, __func__,
> +               (unsigned long)vmcb->exitinfo2,
> +               (unsigned long)regs->error_code,
> +               (unsigned long)regs->eip, (unsigned int)bytes[0],
> +               (unsigned int)bytes[1], bytes_len, inst_len, frc,
> +               cpu_has_svm_nrips, (unsigned long)vmcb->nextrip,
> +               cpu_has_svm_decode, vmcb->guest_ins_len & 0xf, vmcb->guest_ins_len,
> +               vmcb->guest_ins[0], vmcb->guest_ins[1]);
> +
> +    if ( !frc && bytes[0] == 0xed && (regs->edx & 0xffff) == VMPORT_PORT &&
> +         vmcb->exitinfo2 == 0 && regs->error_code == 0 )
> +    {
> +        /*  in (%dx),%eax */
> +        uint32_t magic = regs->eax;
> +
> +        if ( magic == VMPORT_MAGIC ) {
> +            __update_guest_eip(regs, 1);
> +            vmport_ioport(IOREQ_READ, 4, 0, regs);
> +            if (hd->params[HVM_PARAM_VMPORT_LOGMASK] & 0x800000 /* LOG_GP_VMWARE_AFTER */)
> +                printk("[HVM:%d.%d] <%s> "
> +                       "gp: VMware ip=%lx ax=%lx bx=%lx cx=%lx dx=%lx si=%lx di=%lx"
> +                       "\n",
> +                       current->domain->domain_id, current->vcpu_id, __func__,
> +                       (unsigned long)regs->eip,
> +                       (unsigned long)regs->eax, (unsigned long)regs->ebx,
> +                       (unsigned long)regs->ecx, (unsigned long)regs->edx,
> +                       (unsigned long)regs->esi, (unsigned long)regs->edi);
> +            return;
> +        } else {
> +            if (hd->params[HVM_PARAM_VMPORT_LOGMASK] & 0x200000 /* LOG_GP_NOT_VMWARE */)
> +                printk("[HVM:%d.%d] <%s> "
> +                       "gp: ip=%lx ax=%lx bx=%lx cx=%lx dx=%lx si=%lx di=%lx"
> +                       "\n",
> +                       current->domain->domain_id, current->vcpu_id, __func__,
> +                       (unsigned long)regs->eip,
> +                       (unsigned long)regs->eax, (unsigned long)regs->ebx,
> +                       (unsigned long)regs->ecx, (unsigned long)regs->edx,
> +                       (unsigned long)regs->esi, (unsigned long)regs->edi);
> +            hvm_inject_hw_exception(TRAP_gp_fault, regs->error_code);
> +        }
> +    } else if (!frc && regs->error_code == 0
> +               && bytes[0] == 0x0f && bytes[1] == 0x33 && regs->ecx == 0x10000)
> +    {
> +        /* "rdpmc 0x10000" */
> +        /* Not a very good emulation!  But just not faulting is good enough
> +         * to get NetApp booting. */
> +        regs->edx = regs->eax = 0;
> +
> +        __update_guest_eip(regs, inst_len);

What if inst_len is zero? (e.g. if NRIP is not supported?)


-boris

> +
> +        /* Doing the log in this case was too noisy for NetApp, so I moved
> +         * it to 'else' */
> +    } else {
> +        if (hd->params[HVM_PARAM_VMPORT_LOGMASK] & 0x100000 /* LOG_GP_UNKNOWN */) {
> +            printk("[HVM:%d.%d] <%s> "
> +                   "gp: e2=%lx ec=%lx ip=%lx=>0x%x 0x%x(%ld,%d) ax=%lx bx=%lx cx=%lx dx=%lx si=%lx di=%lx"
> +                   "\n",
> +                   current->domain->domain_id, current->vcpu_id, __func__,
> +                   (unsigned long)vmcb->exitinfo2, (unsigned long)regs->error_code,
> +                   (unsigned long)regs->eip, (unsigned int)bytes[0],
> +                   (unsigned int)bytes[1], inst_len, frc,
> +                   (unsigned long)regs->eax, (unsigned long)regs->ebx,
> +                   (unsigned long)regs->ecx, (unsigned long)regs->edx,
> +                   (unsigned long)regs->esi, (unsigned long)regs->edi);
> +        }
> +        hvm_inject_hw_exception(TRAP_gp_fault, regs->error_code);
> +    }
> +}
> +
>