Re: [PATCH v6 1/2] x86/kexec: Build identity mapping for EFI systab and ACPI tables

[Kairui Song <kasong@redhat.com>]

On Tue, May 14, 2019 at 4:48 PM Dave Young <dyoung@redhat.com> wrote:
>
> On 05/14/19 at 11:22am, Dave Young wrote:
> > On 05/13/19 at 04:06pm, Baoquan He wrote:
> > > Hi Dave,
> > >
> > > On 05/13/19 at 09:50am, Borislav Petkov wrote:
> > > > On Mon, May 13, 2019 at 03:32:54PM +0800, Baoquan He wrote:
> > > > > This is a critical bug which breaks memory hotplug,
> > > >
> > > > Please concentrate and stop the blabla:
> > > >
> > > > 36f0c423552d ("x86/boot: Disable RSDP parsing temporarily")
> > > >
> > > > already explains what the deal is. This code was *purposefully* disabled
> > > > because we ran out of time and it broke a couple of machines. Don't make
> > >
> > > I remember your machine is the one on whihc the issue is reported. Could
> > > you also test it and confirm if these all things found ealier are
> > > cleared out?
> > >
> >
> > I did some tests on the laptop,  thing is:
> > 1. apply the 3 patches (two you posted + Boris's revert commit 52b922c3d49c)
> >    on latest Linus master branch, everything works fine.
> >
> > 2. build and test the tip/next-merge-window branch, kernel hangs early
> > without output, (both 1st boot and kexec boot)
>
> Update about 2.  It should be not early rsdp related, I got the boot log
> Since can not reproduce with Linus master branch it may have been fixed.
>
> [    0.685374][    T1] rcu: Hierarchical SRCU implementation.
> [    0.686414][    T1] general protection fault: 0000 [#1] SMP PTI
> [    0.687328][    T1] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.1.0-rc6+ #877
> [    0.687328][    T1] Hardware name: LENOVO 4236NUC/4236NUC, BIOS 83ET82WW (1.52 ) 06/04/2018
> [    0.687328][    T1] RIP: 0010:reserve_ds_buffers+0x34e/0x450
> [    0.687328][    T1] Code: e8 77 49 1a 00 4c 8b 54 24 18 48 85 c0 4c 8b 4c 24 10 48 89 44 24 20 0f 84 68 fe ff ff 4a 8b 0c cd 20 88 07 a7 48 8d 54 24 20 <48> 89 04 11 e9 e5 fd ff ff 85 db 0f 85 67 fe ff ff 45 85 ed 75 24
> [    0.687328][    T1] RSP: 0000:ffffa52100c8bd90 EFLAGS: 00010286
> [    0.687328][    T1] RAX: ffff8c6bd5d03000 RBX: 0000000000000000 RCX: ffff8c6bd6000000
> [    0.687328][    T1] RDX: ffffa52100c8bdb0 RSI: ffffffffa620e209 RDI: ffff8c6bd5d04000
> [    0.687328][    T1] RBP: ffff8c6bd60103a0 R08: ffff8c6bd4da0000 R09: 0000000000000000
> [    0.687328][    T1] R10: ffff8c6bd4e20000 R11: ffffc8e248538800 R12: 00000000000103a0
> [    0.687328][    T1] R13: 0000000000010000 R14: fffffe0000013000 R15: 0000000000000000
> [    0.687328][    T1] FS:  0000000000000000(0000) GS:ffff8c6bd6000000(0000) knlGS:0000000000000000
> [    0.687328][    T1] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [    0.687328][    T1] CR2: ffff8c6bde5ff000 CR3: 000000015700e001 CR4: 00000000000606f0
> [    0.687328][    T1] Call Trace:
> [    0.687328][    T1]  ? hardlockup_detector_event_create+0x50/0x50
> [    0.687328][    T1]  x86_reserve_hardware+0x173/0x180
> [    0.687328][    T1]  x86_pmu_event_init+0x39/0x220
> [    0.687328][    T1]  ? hardlockup_detector_event_create+0x50/0x50
> [    0.687328][    T1]  perf_try_init_event+0x42/0xd0
> [    0.687328][    T1]  perf_event_alloc+0x46a/0x8b0
> [    0.687328][    T1]  perf_event_create_kernel_counter+0x21/0x130
> [    0.687328][    T1]  hardlockup_detector_event_create+0x39/0x50
> [    0.687328][    T1]  hardlockup_detector_perf_init+0xc/0x40
> [    0.687328][    T1]  lockup_detector_init+0x3a/0x71
> [    0.687328][    T1]  kernel_init_freeable+0xbc/0x231
> [    0.687328][    T1]  ? rest_init+0x9f/0x9f
> [    0.687328][    T1]  kernel_init+0xa/0x101
> [    0.687328][    T1]  ret_from_fork+0x35/0x40
> [    0.687328][    T1] Modules linked in:
> [    0.687331][    T1] ---[ end trace 71ee47f6125e74a4 ]---
> [    0.688331][    T1] RIP: 0010:reserve_ds_buffers+0x34e/0x450
> [    0.689330][    T1] Code: e8 77 49 1a 00 4c 8b 54 24 18 48 85 c0 4c 8b 4c 24 10 48 89 44 24 20 0f 84 68 fe ff ff 4a 8b 0c cd 20 88 07 a7 48 8d 54 24 20 <48> 89 04 11 e9 e5 fd ff ff 85 db 0f 85 67 fe ff ff 45 85 ed 75 24
> [    0.690330][    T1] RSP: 0000:ffffa52100c8bd90 EFLAGS: 00010286
> [    0.691330][    T1] RAX: ffff8c6bd5d03000 RBX: 0000000000000000 RCX: ffff8c6bd6000000
> [    0.692330][    T1] RDX: ffffa52100c8bdb0 RSI: ffffffffa620e209 RDI: ffff8c6bd5d04000
> [    0.693330][    T1] RBP: ffff8c6bd60103a0 R08: ffff8c6bd4da0000 R09: 0000000000000000
> [    0.694330][    T1] R10: ffff8c6bd4e20000 R11: ffffc8e248538800 R12: 00000000000103a0
> [    0.695330][    T1] R13: 0000000000010000 R14: fffffe0000013000 R15: 0000000000000000
> [    0.696330][    T1] FS:  0000000000000000(0000) GS:ffff8c6bd6000000(0000) knlGS:0000000000000000
> [    0.697330][    T1] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [    0.698330][    T1] CR2: ffff8c6bde5ff000 CR3: 000000015700e001 CR4: 00000000000606f0
> [    0.699334][    T1] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
> [    0.700328][    T1] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b ]---
>
> Thanks
> Dave

I can confirm as I got same result on my T420. next-merge-window
branch fails both normal boot and kexec...
I didn't manage to get a working serial console, but the behavior is
the same so should be the same issue.

Also after "git cherry-pick de01951c8d40^..next-merge-window" on
master branch, it worked well, so the patch should be good.

--
Best Regards,
Kairui Song