Wednesday, 5 June 2019

Re: Add "dis_ucode_ldr" to linux boot options for Recovery Mode

Thanks. I'll open a report for grub2.
According to the docs, dis_ucode_ldr is x86 only (arch/x86/kernel/cpu/microcode/core.c), so my guess is that it will be ignored for other architectures. According to the kernel code, dis_ucode_ldr works for both AMD and Intel.
I have some time tomorrow on test this on a ARM device.


On Wed, Jun 5, 2019 at 7:49 PM Tyler Hicks <> wrote:
On 2019-06-05 10:03:06, Jeroen Bobbeldijk wrote:
> Hi,
> Due to some recent problems with a microcode update which broke booting of
> some laptops I suggest adding "dis_ucode_ldr" to recovery mode boot options
> to allow booting after a bad microcode update.
> See the following topics that describe the problems:
>  -
>  -
> When such problems occur it's very hard to see that the microcode loading
> is the issue, the booting just hangs at the purple screen, even removing
> "quiet splash" will not show the error.

I really like this idea. Thanks for mentioning it.

Please open a bug report here:

We'll need to double check that dis_ucode_ldr works as expected across
all architectures. Otherwise, I can't think of any other technical
blockers to doing this.


> Kind regards,
> Jeroen

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