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

From: Dirk van der Merwe
Date: Tue May 21 2019 - 17:57:39 EST



On 5/13/19 8:33 PM, Baoquan He 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)
Thanks, Dave.

Yeah, I also tested on a HP machine, problem reprodued on the current
master branch when revert commit 52b922c3d49c.

Then apply these two patches, problem solved.

Tried boris's next-merge-window branch too, kexec works very well.

Dirk, Junichi, feel free to add your test result if you have time.


I tested this with the patches (plus revert of the workaround) applied against stable 5.1 and it works fine for me there. Thanks!

Where can I find the next-merge-window tree?

I can test against that too.


Best regards

Dirk