Re: [elrepo] Announcement: EL7 New kernel-ml Release [4.15.0-1]

On 04/02/18 21:15, David Ranch wrote: Hello Everyone, I have a question about this statement: Kernel-ml has the retpoline patches but at present RHEL does not have a retpoline-aware compiler. The upstream kernel code (kernel.org) does not currently contain the IBRS patches that Red Hat

Re: [elrepo] Announcement: EL7 New kernel-ml Release [4.15.0-1]

Hello Everyone, I have a question about this statement: Kernel-ml has the retpoline patches but at present RHEL does not have a retpoline-aware compiler. The upstream kernel code (kernel.org) does not currently contain the IBRS patches that Red Hat have incorporated into the distro kernel.

Re: [elrepo] Announcement: EL7 New kernel-ml Release [4.15.0-1]

On 30/01/18 23:47, Lachlan Musicman wrote: On 31 Jan. 2018 10:35 am, "Sam McLeod" > wrote: Hi Trevor, I didn't think that to compile a kernel with IBRS/IBPB your /compiler/ had to be updated as well? I thought that was

Re: [elrepo] Announcement: EL7 New kernel-ml Release [4.15.0-1]

Thanks Lachlan, So the key to having IBRS/IBPB is a retpolite aware compiler... >> * Kernel compiled with a retpoline-aware compiler: NO (kernel reports >> minimal retpoline compilation) What a mess this whole thing is (preaching to the choir I'm sure) - it's turned my head inside out

Re: [elrepo] Announcement: EL7 New kernel-ml Release [4.15.0-1]

On 31 Jan. 2018 10:35 am, "Sam McLeod" wrote: Hi Trevor, I didn't think that to compile a kernel with IBRS/IBPB your *compiler* had to be updated as well? I thought that was a seperate issue but perhaps I'm mistaken. Yes, it does require a newer compiler...you can

Re: [elrepo] Announcement: EL7 New kernel-ml Release [4.15.0-1]

Hi Trevor, I didn't think that to compile a kernel with IBRS/IBPB your compiler had to be updated as well? I thought that was a seperate issue but perhaps I'm mistaken. -- Sam McLeod https://smcleod.net https://twitter.com/s_mcleod > On 31 Jan 2018, at 12:22 am, Trevor Hemsley

Re: [elrepo] Announcement: EL7 New kernel-ml Release [4.15.0-1]

Sam I'm not ELRepo but I don't think they can do that until/unless RH fix the compilers in the distro to be retpoline aware. If they do. And, in any case, Intel have pretty much said "don't use the new microcode" so there is no working microcode available that the kernel can use anyway. All the

Re: [elrepo] Announcement: EL7 New kernel-ml Release [4.15.0-1]

For those wondering about the status of Spectre and Meltdown on kernel-ml 4.15, below is the output of the speed47 test (https://github.com/speed47/spectre-meltdown-checker ). I've found this to be consistent between CentOS 7 VMs (PVHVM) on