Re: [x86-tip] RSDP changes converted i4790 box SMP -> UP

From: Mike Galbraith
Date: Fri Jan 12 2018 - 03:01:45 EST


On Fri, 2018-01-12 at 07:40 +0100, Juergen Gross wrote:
> On 12/01/18 05:25, Mike Galbraith wrote:
> > Hi Juergen,
> >
> > Yesterday I wanted to test the RETPOLINE stuff in tip and tip-rt, but
> > discovered instead that my box had turned into a complete slug, not due
> > to incredible RETPOLINE overhead, rather because box had forgotten that
> > it had more than one CPU.  I was going to leave it for the weekend, but
> > firing up gitk over morning java, I noticed the commits below, and sure
> > enough, that's what broke my box.  Given other people's boxen work,
> > seems likely that the authors of the AMI BIOS in this box were a bit
> > more creative than usual.
>
> So I'm curious how this should be possible.

Box is absolutely certain that it is.

> Some questions:
>
> - which bootloader are you using?

grub2, box is bog standard opensuse-42.3

> - what does /sys/kernel/boot_params/version contain?

0x020e

> - can you print the returned value of acpi_arch_get_root_pointer()
> in acpi_os_get_root_pointer() with the patches applied and report
> it, please?

0x115, which doesn't look all that useful to ACPI.

[ 0.000000] ACPI: Early table checksum verification disabled
[ 0.000000] ACPI: MIKE pa = 0x115
[ 0.000000] ACPI: 0x0000000000000115 000000 (v00 00000000 00000000)
[ 0.000000] Reserving 132MB of low memory at 3392MB for crashkernel (System low RAM: 3556MB)
[ 0.000000] Reserving 256MB of memory at 16608MB for crashkernel (System RAM: 16340MB)
[ 0.000000] tsc: Fast TSC calibration using PIT
[ 0.000000] Zone ranges:
[ 0.000000] DMA [mem 0x0000000000001000-0x0000000000ffffff]
[ 0.000000] DMA32 [mem 0x0000000001000000-0x00000000ffffffff]
[ 0.000000] Normal [mem 0x0000000100000000-0x000000041effffff]
[ 0.000000] Movable zone start for each node
[ 0.000000] Early memory node ranges
[ 0.000000] node 0: [mem 0x0000000000001000-0x0000000000057fff]
[ 0.000000] node 0: [mem 0x0000000000059000-0x000000000009dfff]
[ 0.000000] node 0: [mem 0x0000000000100000-0x00000000d0443fff]
[ 0.000000] node 0: [mem 0x00000000d044b000-0x00000000d0889fff]
[ 0.000000] node 0: [mem 0x00000000d0b4b000-0x00000000de787fff]
[ 0.000000] node 0: [mem 0x00000000defff000-0x00000000deffffff]
[ 0.000000] node 0: [mem 0x0000000100000000-0x000000041effffff]
[ 0.000000] Initmem setup node 0 [mem 0x0000000000001000-0x000000041effffff]
[ 0.000000] On node 0 totalpages: 4183133
[ 0.000000] DMA zone: 64 pages used for memmap
[ 0.000000] DMA zone: 21 pages reserved
[ 0.000000] DMA zone: 3996 pages, LIFO batch:0
[ 0.000000] DMA32 zone: 14164 pages used for memmap
[ 0.000000] DMA32 zone: 906433 pages, LIFO batch:31
[ 0.000000] Normal zone: 51136 pages used for memmap
[ 0.000000] Normal zone: 3272704 pages, LIFO batch:31
[ 0.000000] Reserved but unavailable: 99 pages
[ 0.000000] tboot: non-0 tboot_addr but it is not of type E820_TYPE_RESERVED
[ 0.000000] smpboot: Boot CPU (id 0) not listed by BIOS
[ 0.000000] smpboot: Allowing 1 CPUs, 0 hotplug CPUs
[ 0.000000] e820: [mem 0xdf000000-0xf7ffffff] available for PCI devices
[ 0.000000] Booting paravirtualized kernel on bare hardware
[ 0.000000] clocksource: refined-jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645519600211568 ns
[ 0.000000] setup_percpu: NR_CPUS:8 nr_cpumask_bits:8 nr_cpu_ids:1 nr_node_ids:1
[ 0.000000] percpu: Embedded 43 pages/cpu @ (ptrval) s135896 r8192 d32040 u2097152
[ 0.000000] pcpu-alloc: s135896 r8192 d32040 u2097152 alloc=1*2097152
[ 0.000000] pcpu-alloc: [0] 0