RE: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-05-04 Thread Thomas Gleixner
Michael! On Thu, Apr 27 2023 at 14:48, Michael Kelley wrote: > From: Thomas Gleixner Sent: Friday, April 14, 2023 4:44 > PM > > I smoke-tested several Linux guest configurations running on Hyper-V, > using the "kernel/git/tglx/devel.git hotplug" tree as updated on April 26th. > No functional

RE: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-27 Thread Michael Kelley (LINUX)
From: Thomas Gleixner Sent: Friday, April 14, 2023 4:44 PM [snip] > > Conclusion > -- > > Adding the basic parallel bringup mechanism as provided by this series > makes a lot of sense. Improving particular issues as pointed out in the > analysis makes sense too. > > But trying to

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-25 Thread Thomas Gleixner
On Thu, Apr 20 2023 at 17:57, Thomas Gleixner wrote: > On Thu, Apr 20 2023 at 07:51, Sean Christopherson wrote: > Something like the completely untested below should just work whatever > APIC ID the BIOS decided to dice. > > That might just work on SEV too without that GHCB muck, but what do I >

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-24 Thread Paul Menzel
Dear Thomas, Am 20.04.23 um 21:10 schrieb Thomas Gleixner: On Thu, Apr 20 2023 at 18:47, Paul Menzel wrote: Am 20.04.23 um 17:57 schrieb Thomas Gleixner: I quickly applied it on top of your branch, but I am getting: As I said it was untested. I was traveling and did not have access to a

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-21 Thread Thomas Gleixner
On Thu, Apr 20 2023 at 21:10, Thomas Gleixner wrote: > On Thu, Apr 20 2023 at 18:47, Paul Menzel wrote: >> Am 20.04.23 um 17:57 schrieb Thomas Gleixner: >> I quickly applied it on top of your branch, but I am getting: > > As I said it was untested. I was traveling and did not have access to a >

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-20 Thread Thomas Gleixner
On Thu, Apr 20 2023 at 18:47, Paul Menzel wrote: > Am 20.04.23 um 17:57 schrieb Thomas Gleixner: > I quickly applied it on top of your branch, but I am getting: As I said it was untested. I was traveling and did not have access to a machine to even build it completely. Fixed up and tested version

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-20 Thread Paul Menzel
Dear Thomas, Am 20.04.23 um 17:57 schrieb Thomas Gleixner: On Thu, Apr 20 2023 at 07:51, Sean Christopherson wrote: On Thu, Apr 20, 2023, Thomas Gleixner wrote: On Thu, Apr 20 2023 at 10:23, Andrew Cooper wrote: On 20/04/2023 9:32 am, Thomas Gleixner wrote: On Wed, Apr 19, 2023, Andrew

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-20 Thread Thomas Gleixner
On Thu, Apr 20 2023 at 07:51, Sean Christopherson wrote: > On Thu, Apr 20, 2023, Thomas Gleixner wrote: >> On Thu, Apr 20 2023 at 10:23, Andrew Cooper wrote: >> > On 20/04/2023 9:32 am, Thomas Gleixner wrote: >> > > On Wed, Apr 19, 2023, Andrew Cooper wrote: >> > > > This was changed in x2APIC,

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-20 Thread Sean Christopherson
On Thu, Apr 20, 2023, Thomas Gleixner wrote: > On Thu, Apr 20 2023 at 10:23, Andrew Cooper wrote: > > On 20/04/2023 9:32 am, Thomas Gleixner wrote: > > > On Wed, Apr 19, 2023, Andrew Cooper wrote: > > > > This was changed in x2APIC, which made the x2APIC_ID immutable. > > >> I'm pondering to

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-20 Thread Thomas Gleixner
On Thu, Apr 20 2023 at 10:23, Andrew Cooper wrote: > On 20/04/2023 9:32 am, Thomas Gleixner wrote: >> I'm pondering to simply deny parallel mode if x2APIC is not there. > > I'm not sure if that will help much. Spoilsport. > Just because x2APIC is there doesn't mean it's in use.  There are >

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-20 Thread Andrew Cooper
On 20/04/2023 9:32 am, Thomas Gleixner wrote: > On Wed, Apr 19 2023 at 17:21, Andrew Cooper wrote: >> On 19/04/2023 2:50 pm, Andrew Cooper wrote: >> For xAPIC, the APIC_ID register is writeable (at least, model >> specifically), and CPUID is only the value it would have had at reset.  >> So the AP

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-20 Thread Thomas Gleixner
On Wed, Apr 19 2023 at 17:21, Andrew Cooper wrote: > On 19/04/2023 2:50 pm, Andrew Cooper wrote: >> What I'm confused by is why this system boots in the first place.  I can >> only think that's is a system which only has 4-bit APIC IDs, and happens >> to function when bit 4 gets truncated off the

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-19 Thread Paul Menzel
Dear Thomas, Am 19.04.23 um 14:38 schrieb Thomas Gleixner: On Wed, Apr 19 2023 at 11:38, Thomas Gleixner wrote: On Tue, Apr 18 2023 at 22:10, Paul Menzel wrote: Am 18.04.23 um 10:40 schrieb Thomas Gleixner: Can you please provide the output of cpuid? Of course. Here the top, and the whole

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-19 Thread Andrew Cooper
On 19/04/2023 2:50 pm, Andrew Cooper wrote: > On 19/04/2023 2:43 pm, Thomas Gleixner wrote: >> On Wed, Apr 19 2023 at 14:38, Thomas Gleixner wrote: >>> On Wed, Apr 19 2023 at 11:38, Thomas Gleixner wrote: >>> IOW, the BIOS assignes random numbers to the AP APICs for whatever >>> raisins, which

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-19 Thread Andrew Cooper
On 19/04/2023 2:43 pm, Thomas Gleixner wrote: > On Wed, Apr 19 2023 at 14:38, Thomas Gleixner wrote: >> On Wed, Apr 19 2023 at 11:38, Thomas Gleixner wrote: >> IOW, the BIOS assignes random numbers to the AP APICs for whatever >> raisins, which leaves the parallel startup low level code up a creek

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-19 Thread Thomas Gleixner
On Wed, Apr 19 2023 at 14:38, Thomas Gleixner wrote: > On Wed, Apr 19 2023 at 11:38, Thomas Gleixner wrote: > IOW, the BIOS assignes random numbers to the AP APICs for whatever > raisins, which leaves the parallel startup low level code up a creek > without a paddle, except for actually reading

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-19 Thread David Woodhouse
On Wed, 2023-04-19 at 14:38 +0200, Thomas Gleixner wrote: > > I'm leaning towards disabling the CPUID lead 0x01 based discovery and be > done with it. Makes sense. The large machines where users really want the parallel startup all ought to have X2APIC and hence CPUID 0x0b. smime.p7s

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-19 Thread Thomas Gleixner
On Wed, Apr 19 2023 at 11:38, Thomas Gleixner wrote: > On Tue, Apr 18 2023 at 22:10, Paul Menzel wrote: >> Am 18.04.23 um 10:40 schrieb Thomas Gleixner: >>> Can you please provide the output of cpuid? >> >> Of course. Here the top, and the whole output is attached. > > Thanks for the data. Can you

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-19 Thread Thomas Gleixner
Paul! On Tue, Apr 18 2023 at 22:10, Paul Menzel wrote: > Am 18.04.23 um 10:40 schrieb Thomas Gleixner: >> Can you please provide the output of cpuid? > > Of course. Here the top, and the whole output is attached. Thanks for the data. Can you please apply the debug patch below and provide the

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-18 Thread Paul Menzel
Dear Thomas, Am 18.04.23 um 10:40 schrieb Thomas Gleixner: On Tue, Apr 18 2023 at 08:58, Thomas Gleixner wrote: On Mon, Apr 17 2023 at 19:40, Paul Menzel wrote: Am 17.04.23 um 16:48 schrieb Thomas Gleixner: On Mon, Apr 17 2023 at 13:19, Paul Menzel wrote: Am 15.04.23 um 01:44 schrieb

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-18 Thread Thomas Gleixner
On Tue, Apr 18 2023 at 08:58, Thomas Gleixner wrote: > On Mon, Apr 17 2023 at 19:40, Paul Menzel wrote: >> Am 17.04.23 um 16:48 schrieb Thomas Gleixner: >> >>> On Mon, Apr 17 2023 at 13:19, Paul Menzel wrote: Am 15.04.23 um 01:44 schrieb Thomas Gleixner: [0.258193] smpboot: CPU0: AMD

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-18 Thread Thomas Gleixner
Paul! On Mon, Apr 17 2023 at 19:40, Paul Menzel wrote: > Am 17.04.23 um 16:48 schrieb Thomas Gleixner: > >> On Mon, Apr 17 2023 at 13:19, Paul Menzel wrote: >>> Am 15.04.23 um 01:44 schrieb Thomas Gleixner: >>> [0.258193] smpboot: CPU0: AMD A6-6400K APU with Radeon(tm) HD >>> Graphics

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-17 Thread Paul Menzel
Dear Thomas, Am 17.04.23 um 16:48 schrieb Thomas Gleixner: On Mon, Apr 17 2023 at 13:19, Paul Menzel wrote: Am 15.04.23 um 01:44 schrieb Thomas Gleixner: [0.258193] smpboot: CPU0: AMD A6-6400K APU with Radeon(tm) HD Graphics (family: 0x15, model: 0x13, stepping: 0x1) […] [0.259329]

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-17 Thread Thomas Gleixner
Paul! On Mon, Apr 17 2023 at 13:19, Paul Menzel wrote: > Am 15.04.23 um 01:44 schrieb Thomas Gleixner: > [0.258193] smpboot: CPU0: AMD A6-6400K APU with Radeon(tm) HD > Graphics (family: 0x15, model: 0x13, stepping: 0x1) > […] > [0.259329] smp: Bringing up secondary CPUs ... > [

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-17 Thread Paul Menzel
[Correct David’s address] Am 17.04.23 um 13:19 schrieb Paul Menzel: Dear Thomas, Am 15.04.23 um 01:44 schrieb Thomas Gleixner: This is a complete rework of the parallel bringup patch series (V17) https://lore.kernel.org/lkml/20230328195758.1049469-1-usama.a...@bytedance.com to

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-17 Thread Paul Menzel
Dear Thomas, Am 15.04.23 um 01:44 schrieb Thomas Gleixner: This is a complete rework of the parallel bringup patch series (V17) https://lore.kernel.org/lkml/20230328195758.1049469-1-usama.a...@bytedance.com to address the issues which were discovered in review: […] Thank you very

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-17 Thread Andrew Cooper
On 17/04/2023 11:30 am, Peter Zijlstra wrote: > On Sat, Apr 15, 2023 at 01:44:13AM +0200, Thomas Gleixner wrote: > >> Background >> -- >> >> The reason why people are interested in parallel bringup is to shorten >> the (kexec) reboot time of cloud servers to reduce the downtime of the >>

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-17 Thread Peter Zijlstra
On Sat, Apr 15, 2023 at 01:44:13AM +0200, Thomas Gleixner wrote: > Background > -- > > The reason why people are interested in parallel bringup is to shorten > the (kexec) reboot time of cloud servers to reduce the downtime of the > VM tenants. There are obviously other interesting use

Re: [patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-17 Thread Juergen Gross
On 15.04.23 01:44, Thomas Gleixner wrote: Hi! This is a complete rework of the parallel bringup patch series (V17) https://lore.kernel.org/lkml/20230328195758.1049469-1-usama.a...@bytedance.com to address the issues which were discovered in review: 1) The X86 microcode loader

[patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

2023-04-14 Thread Thomas Gleixner
Hi! This is a complete rework of the parallel bringup patch series (V17) https://lore.kernel.org/lkml/20230328195758.1049469-1-usama.a...@bytedance.com to address the issues which were discovered in review: 1) The X86 microcode loader serialization requirement