Hi Paolo, On Mon, Feb 26, 2024 at 10:55:14AM +0100, Paolo Bonzini wrote: > Date: Mon, 26 Feb 2024 10:55:14 +0100 > From: Paolo Bonzini <pbonz...@redhat.com> > Subject: Re: [PATCH v2 4/7] target/i386: use separate MMU indexes for > 32-bit accesses > > On Mon, Feb 26, 2024 at 9:22 AM Zhao Liu <zhao1....@intel.com> wrote: > > On Fri, Feb 23, 2024 at 02:09:45PM +0100, Paolo Bonzini wrote: > > > Accesses from a 32-bit environment (32-bit code segment for instruction > > > accesses, EFER.LMA==0 for processor accesses) have to mask away the > > > upper 32 bits of the address. While a bit wasteful, the easiest way > > > to do so is to use separate MMU indexes. These days, QEMU anyway is > > > compiled with a fixed value for NB_MMU_MODES. Split MMU_USER_IDX, > > > MMU_KSMAP_IDX and MMU_KNOSMAP_IDX in two. > > > > Maybe s/in/into/ ? > > Both are acceptable grammar. > > > > static inline int cpu_mmu_index_kernel(CPUX86State *env) > > > { > > > - return !(env->hflags & HF_SMAP_MASK) ? MMU_KNOSMAP_IDX : > > > - ((env->hflags & HF_CPL_MASK) < 3 && (env->eflags & AC_MASK)) > > > - ? MMU_KNOSMAP_IDX : MMU_KSMAP_IDX; > > > + int mmu_index_32 = (env->hflags & HF_LMA_MASK) ? 1 : 0; > > > + int mmu_index_base = > > > + !(env->hflags & HF_SMAP_MASK) ? MMU_KNOSMAP64_IDX : > > > + ((env->hflags & HF_CPL_MASK) < 3 && (env->eflags & AC_MASK)) ? > > > MMU_KNOSMAP64_IDX : MMU_KSMAP64_IDX; > > > Change the line? > > It's reformatted but the logic is the same. > > - if !SMAP -> MMU_KNOSMAP_IDX > > - if CPL < 3 && EFLAGS.AC - MMU_KNOSMAP_IDX > > - else MMU_KSMAP_IDX > > The only change is adding the "64" suffix, which is then changed to > 32-bit if needed via mmu_index_32. >
Thanks for the explanation, I get your point. Similarly, I also understand your change in x86_cpu_mmu_index(). LGTM, please allow me to add my review tag: Reviewed-by: Zhao Liu <zhao1....@intel.com>