Re: [PATCH] x86/cmdline: Disable instrumentation of cmdline unconditionally

From: Borislav Petkov
Date: Thu Sep 17 2020 - 05:41:06 EST


On Sun, Sep 06, 2020 at 11:46:37AM -0400, Arvind Sankar wrote:
> On 32-bit, cmdline_find_option_bool() is used before paging is enabled,
> from check_loader_disabled_bsp() in the early microcode loader.
> Instrumentation options that insert accesses to global data will likely
> crash or corrupt memory at this point.

What is the use case here, can you trigger an actual crash?

--
Regards/Gruss,
Boris.

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