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This is redundancy. Instead, set both bits first and write CR4 once, avoiding redundant writes. This makes consistent with cr0 writes, which is set bits and write once. Signed-off-by: Khalid Ali --- arch/x86/kernel/head_64.S | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 4390a28f7dad..dfb5390e5c9a 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -222,12 +222,9 @@ SYM_INNER_LABEL(common_startup_64, SYM_L_LOCAL) /* Even if ignored in long mode, set PSE uniformly on all logical CPUs. */ btsl $X86_CR4_PSE_BIT, %ecx - movq %rcx, %cr4 - - /* - * Set CR4.PGE to re-enable global translations. - */ + /* Set CR4.PGE to re-enable global translations. */ btsl $X86_CR4_PGE_BIT, %ecx + movq %rcx, %cr4 #ifdef CONFIG_SMP -- 2.49.0