Re: [Bug 1855617] [NEW] savevm with hax saves wrong register state

[Dr. David Alan Gilbert]

cc'ing Colin and Yu for Hax info:

* Alex (address@hidden) wrote:
> Public bug reported:
> 
> I use qemu-i386 with IntelHaxm on Windows 10 x64 host with Windows 7 x86 
> guest. I run the guest till OS loads and create a snapshot with savevm, then 
> close qemu, run it again and try to load the snapshot with loadvm. The guest 
> crashes or freezes. I dumped registers on snapshot creation and loading (in 
> Haxm) and found that they are different.
> When returning from Haxm in hax_vcpu_hax_exec, there is no regular register 
> read. I found hax_arch_get_registers function which reads registers from Haxm 
> and is called from a synchronization procedure. I placed a breakpoint on it, 
> ran qemu and found that it is hit one time during guest OS boot. Exactly 
> these registers where saved in the snapshot.
> 
> ** Affects: qemu
>      Importance: Undecided
>          Status: New
> 
> -- 
> You received this bug notification because you are a member of qemu-
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> https://bugs.launchpad.net/bugs/1855617
> 
> Title:
>   savevm with hax saves wrong register state
> 
> Status in QEMU:
>   New
> 
> Bug description:
>   I use qemu-i386 with IntelHaxm on Windows 10 x64 host with Windows 7 x86 
> guest. I run the guest till OS loads and create a snapshot with savevm, then 
> close qemu, run it again and try to load the snapshot with loadvm. The guest 
> crashes or freezes. I dumped registers on snapshot creation and loading (in 
> Haxm) and found that they are different.
>   When returning from Haxm in hax_vcpu_hax_exec, there is no regular register 
> read. I found hax_arch_get_registers function which reads registers from Haxm 
> and is called from a synchronization procedure. I placed a breakpoint on it, 
> ran qemu and found that it is hit one time during guest OS boot. Exactly 
> these registers where saved in the snapshot.
> 
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> 
--
Dr. David Alan Gilbert / address@hidden / Manchester, UK