Re: [Xen-devel] [PATCH V2] x86, amd_ucode: Skip microcode updates for final levels

2015-08-03 Thread Aravind Gopalakrishnan
On 8/3/2015 2:00 PM, Boris Ostrovsky wrote: On 08/03/2015 02:42 PM, Aravind Gopalakrishnan wrote: Ah. I see what you mean. I can think of two ways around this- a. I can move the check_final_patch_levels() call to apply_microcode(). That way, our initial checks in microcode_fits() would have a

Re: [Xen-devel] [PATCH V2] x86, amd_ucode: Skip microcode updates for final levels

2015-08-03 Thread Boris Ostrovsky
On 08/03/2015 02:42 PM, Aravind Gopalakrishnan wrote: Ah. I see what you mean. I can think of two ways around this- a. I can move the check_final_patch_levels() call to apply_microcode(). That way, our initial checks in microcode_fits() would have already checked equivalent cpu IDs so we know

Re: [Xen-devel] [PATCH V2] x86, amd_ucode: Skip microcode updates for final levels

2015-08-03 Thread Aravind Gopalakrishnan
On 8/3/2015 1:18 PM, Boris Ostrovsky wrote: On 08/03/2015 01:52 PM, Aravind Gopalakrishnan wrote: On 8/3/2015 12:22 PM, Boris Ostrovsky wrote: On 08/03/2015 12:35 PM, Aravind Gopalakrishnan wrote: Some of older[Fam10h] systems require that certain number of applied microcode patch levels shoul

Re: [Xen-devel] [PATCH V2] x86, amd_ucode: Skip microcode updates for final levels

2015-08-03 Thread Boris Ostrovsky
On 08/03/2015 01:52 PM, Aravind Gopalakrishnan wrote: On 8/3/2015 12:22 PM, Boris Ostrovsky wrote: On 08/03/2015 12:35 PM, Aravind Gopalakrishnan wrote: Some of older[Fam10h] systems require that certain number of applied microcode patch levels should not be overwritten by the microcode loader.

Re: [Xen-devel] [PATCH V2] x86, amd_ucode: Skip microcode updates for final levels

2015-08-03 Thread Aravind Gopalakrishnan
On 8/3/2015 12:22 PM, Boris Ostrovsky wrote: On 08/03/2015 12:35 PM, Aravind Gopalakrishnan wrote: Some of older[Fam10h] systems require that certain number of applied microcode patch levels should not be overwritten by the microcode loader. Otherwise, system hangs are known to occur. The 'fina

Re: [Xen-devel] [PATCH V2] x86, amd_ucode: Skip microcode updates for final levels

2015-08-03 Thread Boris Ostrovsky
On 08/03/2015 12:35 PM, Aravind Gopalakrishnan wrote: Some of older[Fam10h] systems require that certain number of applied microcode patch levels should not be overwritten by the microcode loader. Otherwise, system hangs are known to occur. The 'final_levels' of patch ids have been obtained empi

Re: [Xen-devel] [PATCH V2] x86, amd_ucode: Skip microcode updates for final levels

2015-08-03 Thread Andrew Cooper
On 03/08/15 17:35, Aravind Gopalakrishnan wrote: > Some of older[Fam10h] systems require that certain number of > applied microcode patch levels should not be overwritten by > the microcode loader. Otherwise, system hangs are known to occur. > > The 'final_levels' of patch ids have been obtained em

[Xen-devel] [PATCH V2] x86, amd_ucode: Skip microcode updates for final levels

2015-08-03 Thread Aravind Gopalakrishnan
Some of older[Fam10h] systems require that certain number of applied microcode patch levels should not be overwritten by the microcode loader. Otherwise, system hangs are known to occur. The 'final_levels' of patch ids have been obtained empirically. Refer bug https://bugzilla.suse.com/show_bug.cg