Commit 961c6a43 authored by Juergen Gross's avatar Juergen Gross Committed by Borislav Petkov (AMD)
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x86/mtrr: Allocate mtrr_value array dynamically 



The mtrr_value[] array is a static variable which is used only in a few
configurations. Consuming 6kB is ridiculous for this case, especially as
the array doesn't need to be that large and it can easily be allocated
dynamically.

Signed-off-by: default avatarJuergen Gross <jgross@suse.com>
Signed-off-by: default avatarBorislav Petkov (AMD) <bp@alien8.de>
Tested-by: default avatarMichael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20230502120931.20719-10-jgross@suse.com


Signed-off-by: default avatarBorislav Petkov (AMD) <bp@alien8.de>
parent b5d3c728

arch/x86/kernel/cpu/mtrr/legacy.c

+7 −1
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-only



#include <linux/types.h>

#include <linux/slab.h>

#include <linux/syscore_ops.h>

#include <asm/cpufeature.h>

#include <asm/mtrr.h>
@@ -38,12 +39,15 @@ struct mtrr_value { 
	unsigned long	lsize;

};



static struct mtrr_value mtrr_value[MTRR_MAX_VAR_RANGES];

static struct mtrr_value *mtrr_value;



static int mtrr_save(void)

{

	int i;



	if (!mtrr_value)

		return -ENOMEM;



	for (i = 0; i < num_var_ranges; i++) {

		mtrr_if->get(i, &mtrr_value[i].lbase,

				&mtrr_value[i].lsize,
@@ -72,6 +76,8 @@ static struct syscore_ops mtrr_syscore_ops = { 


void mtrr_register_syscore(void)

{

	mtrr_value = kcalloc(num_var_ranges, sizeof(*mtrr_value), GFP_KERNEL);



	/*

	 * The CPU has no MTRR and seems to not support SMP. They have

	 * specific drivers, we use a tricky method to support