[Qemu-devel] PC value translation from guest VA to host VA.

[Qemu-devel] PC value translation from guest VA to host VA.

[Gaurav Sharma]

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Can anyone point it out to me where is the pc value translated from guest
virtual address to host virtual address ?

Thanks,
Gaurav

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Re: [Qemu-devel] PC value translation from guest VA to host VA.

[Gaurav Sharma]

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To elaborate a bit more ...
If the target is arm, in disas_arm_insn function we fetch the opcode as per
the pc value :
insn = arm_ldl_code(env, s->pc, s->bswap_code)

This PC value i could trace back and see actually come from the cpu
register set for arm regs[15]. which is the pc value.
Is this PC value a target virtual address or the host virtual address ?
How is the translation done ?

Thanks,
Gaurav



On Wed, Feb 12, 2014 at 1:17 PM, Gaurav Sharma <gauravs.2010@gmail.com>wrote:

> Can anyone point it out to me where is the pc value translated from guest
> virtual address to host virtual address ?
>
> Thanks,
> Gaurav
>

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Re: [Qemu-devel] PC value translation from guest VA to host VA.

[Hu Tao]

On Wed, Feb 12, 2014 at 05:42:00PM +0530, Gaurav Sharma wrote:
> To elaborate a bit more ...
> If the target is arm, in disas_arm_insn function we fetch the opcode as per the
> pc value :
> insn = arm_ldl_code(env, s->pc, s->bswap_code)
> 
> This PC value i could trace back and see actually come from the cpu register
> set for arm regs[15]. which is the pc value.
> Is this PC value a target virtual address or the host virtual address ?
> How is the translation done ?

It's target virtual address, translated to target physical address by
softmmu.  Target physical address is mapped to host virtual address by
qemu memory model, see docs/memory.txt.