Turning the MMU on is a popular sport in the arm64 kernel, and we do it more than once, or even twice. As we are about to add even more, let's turn it into a macro. No expected functional change. Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx> --- arch/arm64/include/asm/assembler.h | 17 +++++++++++++++++ arch/arm64/kernel/head.S | 19 ++++--------------- arch/arm64/mm/proc.S | 12 +----------- 3 files changed, 22 insertions(+), 26 deletions(-) diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index bf125c591116..8cded93f99c3 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -675,6 +675,23 @@ USER(\label, ic ivau, \tmp2) // invalidate I line PoU .endif .endm +/* + * Set SCTLR_EL1 to the passed value, and invalidate the local icache + * in the process. This is called when setting the MMU on. + */ +.macro set_sctlr_el1, reg + msr sctlr_el1, \reg + isb + /* + * Invalidate the local I-cache so that any instructions fetched + * speculatively from the PoC are discarded, since they may have + * been dynamically patched at the PoU. + */ + ic iallu + dsb nsh + isb +.endm + /* * Check whether to yield to another runnable task from kernel mode NEON code * (which runs with preemption disabled). diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index a0dc987724ed..28e9735302df 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -703,16 +703,9 @@ SYM_FUNC_START(__enable_mmu) offset_ttbr1 x1, x3 msr ttbr1_el1, x1 // load TTBR1 isb - msr sctlr_el1, x0 - isb - /* - * Invalidate the local I-cache so that any instructions fetched - * speculatively from the PoC are discarded, since they may have - * been dynamically patched at the PoU. - */ - ic iallu - dsb nsh - isb + + set_sctlr_el1 x0 + ret SYM_FUNC_END(__enable_mmu) @@ -883,11 +876,7 @@ SYM_FUNC_START_LOCAL(__primary_switch) tlbi vmalle1 // Remove any stale TLB entries dsb nsh - msr sctlr_el1, x19 // re-enable the MMU - isb - ic iallu // flush instructions fetched - dsb nsh // via old mapping - isb + set_sctlr_el1 x19 // re-enable the MMU bl __relocate_kernel #endif diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index ece785477bdc..c967bfd30d2b 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -291,17 +291,7 @@ skip_pgd: /* We're done: fire up the MMU again */ mrs x17, sctlr_el1 orr x17, x17, #SCTLR_ELx_M - msr sctlr_el1, x17 - isb - - /* - * Invalidate the local I-cache so that any instructions fetched - * speculatively from the PoC are discarded, since they may have - * been dynamically patched at the PoU. - */ - ic iallu - dsb nsh - isb + set_sctlr_el1 x17 /* Set the flag to zero to indicate that we're all done */ str wzr, [flag_ptr] -- 2.29.2 _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
