On 22.08.22 10:28, Borislav Petkov wrote:
On Mon, Aug 22, 2022 at 07:17:40AM +0200, Juergen Gross wrote:
And then there is mtrr_state_warn() in arch/x86/kernel/cpu/mtrr/generic.c which has a comment saying:
/* Some BIOS's are messed up and don't set all MTRRs the same! */
That thing also says:
pr_info("mtrr: probably your BIOS does not setup all CPUs.\n"); pr_info("mtrr: corrected configuration.\n");because it'll go and force on all CPUs the MTRR state it read from the BSP in mtrr_bp_init->get_mtrr_state.
Yes, the chances are slim to hit such a box,
Well, my workstation says:
$ dmesg | grep -i mtrr [ 0.391514] mtrr: your CPUs had inconsistent variable MTRR settings [ 0.395199] mtrr: probably your BIOS does not setup all CPUs. [ 0.399199] mtrr: corrected configuration.
but that's the variable MTRRs.
but your reasoning suggests I should remove the related code?
My reasoning says you should not do anything at all here - works as advertized. :-)
And what about the:
pr_warn("mtrr: your CPUs had inconsistent MTRRdefType settings\n");
This is the case the patch would fix.
Juergen