Hi Marc, On Tue, Mar 19, 2024 at 09:43:03AM +0000, Marc Zyngier wrote: > This seems pretty reasonable, thanks for looking into this. However, I > can't help but notice that this is done without any BBM, and no TLBI > either. > > Are we guaranteed that the updated page tables are not live at the > point of update?
This means gd->arch.tlb_addr pointing to the live PTs during setup_pgtables(). In arch/arm/cpu/armv8, setup_all_pgtables() runs with SCTLR_ELx.M unset. In arch/arm/cpu/armv8/fsl-layerscape, setup_pgtables() is called twice: - early_mmu_setup() calls it with SCTLR_ELx.M unset; - final_mmu_setup() overwrites gd->arch.tlb_addr before calling it iff CFG_SYS_MEM_RESERVE_SECURE is defined i.e. if CONFIG_SYS_SOC="fsl-layerscape" so that <asm/arch-fsl-layerscape/config.h> gets auto-included through <include/config.h>. So can CONFIG_FSL_LAYERSCAPE be set while CONFIG_SYS_SOC != "fsl-layerscape"? I suppose Fabio and Stefano can answer this and/or help with ensuring that setup_pgtables() is never called on live PTs. Thanks, -- Pierre
