Re: [Qemu-devel] [RFC PATCH] spapr: add initial ibm, client-architecture-support rtas call support

2013-09-05 Thread Paul Mackerras
On Wed, Sep 04, 2013 at 04:32:20PM -0500, Anthony Liguori wrote: On Wed, Sep 4, 2013 at 8:37 AM, Alexander Graf ag...@suse.de wrote: So IMHO this whole thing should be orthogonal to -cpu. Well, since we cannot change CPU class on the fly, yes, it should be a compatibility

Re: [Qemu-devel] [RFC PATCH] spapr: add initial ibm, client-architecture-support rtas call support

2013-09-05 Thread Alexander Graf
On 05.09.2013, at 12:16, Paul Mackerras wrote: On Wed, Sep 04, 2013 at 04:32:20PM -0500, Anthony Liguori wrote: On Wed, Sep 4, 2013 at 8:37 AM, Alexander Graf ag...@suse.de wrote: So IMHO this whole thing should be orthogonal to -cpu. Well, since we cannot change CPU class on the fly,

Re: [Qemu-devel] [RFC PATCH] spapr: add initial ibm, client-architecture-support rtas call support

2013-09-05 Thread Paul Mackerras
On Thu, Sep 05, 2013 at 12:19:09PM +0200, Alexander Graf wrote: On 05.09.2013, at 12:16, Paul Mackerras wrote: On Wed, Sep 04, 2013 at 04:32:20PM -0500, Anthony Liguori wrote: On Wed, Sep 4, 2013 at 8:37 AM, Alexander Graf ag...@suse.de wrote: So IMHO this whole thing should be

Re: [Qemu-devel] [RFC PATCH] spapr: add initial ibm, client-architecture-support rtas call support

2013-09-05 Thread Alexander Graf
On 05.09.2013, at 13:55, Paul Mackerras wrote: On Thu, Sep 05, 2013 at 12:19:09PM +0200, Alexander Graf wrote: On 05.09.2013, at 12:16, Paul Mackerras wrote: On Wed, Sep 04, 2013 at 04:32:20PM -0500, Anthony Liguori wrote: On Wed, Sep 4, 2013 at 8:37 AM, Alexander Graf ag...@suse.de

[Qemu-devel] [RFC PATCH] spapr: add initial ibm, client-architecture-support rtas call support

2013-09-04 Thread Alexey Kardashevskiy
This is an RFC patch. The modern Linux kernel supports every known POWERPC CPU so when it boots, it can always find a matching cpu_spec from the cpu_specs array. However if the kernel is quite old, it may be missing the definition of the actual CPU. To provide ability for old kernels to work

Re: [Qemu-devel] [RFC PATCH] spapr: add initial ibm, client-architecture-support rtas call support

2013-09-04 Thread Alexander Graf
On 04.09.2013, at 12:19, Alexey Kardashevskiy wrote: This is an RFC patch. The modern Linux kernel supports every known POWERPC CPU so when it boots, it can always find a matching cpu_spec from the cpu_specs array. However if the kernel is quite old, it may be missing the definition of

Re: [Qemu-devel] [RFC PATCH] spapr: add initial ibm, client-architecture-support rtas call support

2013-09-04 Thread Alexey Kardashevskiy
On 09/04/2013 08:42 PM, Alexander Graf wrote: On 04.09.2013, at 12:19, Alexey Kardashevskiy wrote: This is an RFC patch. The modern Linux kernel supports every known POWERPC CPU so when it boots, it can always find a matching cpu_spec from the cpu_specs array. However if the kernel is

Re: [Qemu-devel] [RFC PATCH] spapr: add initial ibm, client-architecture-support rtas call support

2013-09-04 Thread Benjamin Herrenschmidt
On Wed, 2013-09-04 at 21:40 +1000, Alexey Kardashevskiy wrote: One of the examples (came from Paul) is: the host runs on POWER8, the guest boots a kernel which is capable of POWER7 only + POWER7-compat. We do this reboot tweak and boot in POWER7-compat mode. Then the guest does yum update and

Re: [Qemu-devel] [RFC PATCH] spapr: add initial ibm, client-architecture-support rtas call support

2013-09-04 Thread Alexander Graf
On 04.09.2013, at 13:40, Alexey Kardashevskiy wrote: On 09/04/2013 08:42 PM, Alexander Graf wrote: On 04.09.2013, at 12:19, Alexey Kardashevskiy wrote: This is an RFC patch. The modern Linux kernel supports every known POWERPC CPU so when it boots, it can always find a matching

Re: [Qemu-devel] [RFC PATCH] spapr: add initial ibm, client-architecture-support rtas call support

2013-09-04 Thread Alexey Kardashevskiy
On 09/04/2013 09:54 PM, Benjamin Herrenschmidt wrote: On Wed, 2013-09-04 at 21:40 +1000, Alexey Kardashevskiy wrote: One of the examples (came from Paul) is: the host runs on POWER8, the guest boots a kernel which is capable of POWER7 only + POWER7-compat. We do this reboot tweak and boot in

Re: [Qemu-devel] [RFC PATCH] spapr: add initial ibm, client-architecture-support rtas call support

2013-09-04 Thread Alexander Graf
On 04.09.2013, at 15:08, Alexey Kardashevskiy wrote: On 09/04/2013 10:13 PM, Alexander Graf wrote: On 04.09.2013, at 13:40, Alexey Kardashevskiy wrote: On 09/04/2013 08:42 PM, Alexander Graf wrote: On 04.09.2013, at 12:19, Alexey Kardashevskiy wrote: This is an RFC patch. The

Re: [Qemu-devel] [RFC PATCH] spapr: add initial ibm, client-architecture-support rtas call support

2013-09-04 Thread Alexey Kardashevskiy
On 09/04/2013 10:13 PM, Alexander Graf wrote: On 04.09.2013, at 13:40, Alexey Kardashevskiy wrote: On 09/04/2013 08:42 PM, Alexander Graf wrote: On 04.09.2013, at 12:19, Alexey Kardashevskiy wrote: This is an RFC patch. The modern Linux kernel supports every known POWERPC CPU so when

Re: [Qemu-devel] [RFC PATCH] spapr: add initial ibm, client-architecture-support rtas call support

2013-09-04 Thread Anthony Liguori
On Wed, Sep 4, 2013 at 8:37 AM, Alexander Graf ag...@suse.de wrote: So IMHO this whole thing should be orthogonal to -cpu. Well, since we cannot change CPU class on the fly, yes, it should be a compatibility flags/properties/methods/whatever of the default CPU for the specific family.