On Tue, Jun 07, 2016 at 11:58:28AM +0100, Marc Zyngier wrote: > We're in a position where we can now always have "merged" page > tables, where both the runtime mapping and the idmap coexist. > > This results in some code being removed, but there is more to come. > > Signed-off-by: Marc Zyngier <[email protected]> > --- > arch/arm/kvm/mmu.c | 74 > +++++++++++++++++++++++--------------------------- > arch/arm64/kvm/reset.c | 31 +++++---------------- > 2 files changed, 41 insertions(+), 64 deletions(-) > > diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c > index d6ecbf1..9a17e14 100644 > --- a/arch/arm/kvm/mmu.c > +++ b/arch/arm/kvm/mmu.c > @@ -492,13 +492,12 @@ void free_boot_hyp_pgd(void) > > if (boot_hyp_pgd) { > unmap_hyp_range(boot_hyp_pgd, hyp_idmap_start, PAGE_SIZE); > - unmap_hyp_range(boot_hyp_pgd, TRAMPOLINE_VA, PAGE_SIZE); > free_pages((unsigned long)boot_hyp_pgd, hyp_pgd_order); > boot_hyp_pgd = NULL; > } > > if (hyp_pgd) > - unmap_hyp_range(hyp_pgd, TRAMPOLINE_VA, PAGE_SIZE); > + unmap_hyp_range(hyp_pgd, hyp_idmap_start, PAGE_SIZE); > > mutex_unlock(&kvm_hyp_pgd_mutex); > } > @@ -1690,7 +1689,7 @@ phys_addr_t kvm_mmu_get_boot_httbr(void) > if (__kvm_cpu_uses_extended_idmap()) > return virt_to_phys(merged_hyp_pgd); > else > - return virt_to_phys(boot_hyp_pgd); > + return virt_to_phys(hyp_pgd); > } > > phys_addr_t kvm_get_idmap_vector(void) > @@ -1703,6 +1702,22 @@ phys_addr_t kvm_get_idmap_start(void) > return hyp_idmap_start; > } > > +static int kvm_map_idmap_text(pgd_t *pgd) > +{ > + int err; > + > + /* Create the idmap in the boot page tables */ > + err = __create_hyp_mappings(pgd, > + hyp_idmap_start, hyp_idmap_end, > + __phys_to_pfn(hyp_idmap_start), > + PAGE_HYP); > + if (err) > + kvm_err("Failed to idmap %lx-%lx\n", > + hyp_idmap_start, hyp_idmap_end); > + > + return err; > +} > + > int kvm_mmu_init(void) > { > int err; > @@ -1718,27 +1733,25 @@ int kvm_mmu_init(void) > BUG_ON((hyp_idmap_start ^ (hyp_idmap_end - 1)) & PAGE_MASK); > > hyp_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, > hyp_pgd_order); > - boot_hyp_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, > hyp_pgd_order); > - > - if (!hyp_pgd || !boot_hyp_pgd) { > + if (!hyp_pgd) { > kvm_err("Hyp mode PGD not allocated\n"); > err = -ENOMEM; > goto out; > } > > - /* Create the idmap in the boot page tables */ > - err = __create_hyp_mappings(boot_hyp_pgd, > - hyp_idmap_start, hyp_idmap_end, > - __phys_to_pfn(hyp_idmap_start), > - PAGE_HYP); > + if (__kvm_cpu_uses_extended_idmap()) { > + boot_hyp_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL | > __GFP_ZERO, > + hyp_pgd_order); > + if (!boot_hyp_pgd) { > + kvm_err("Hyp boot PGD not allocated\n"); > + err = -ENOMEM; > + goto out; > + } > > - if (err) { > - kvm_err("Failed to idmap %lx-%lx\n", > - hyp_idmap_start, hyp_idmap_end); > - goto out; > - } > + err = kvm_map_idmap_text(boot_hyp_pgd); > + if (err) > + goto out; > > - if (__kvm_cpu_uses_extended_idmap()) { > merged_hyp_pgd = (pgd_t *)__get_free_page(GFP_KERNEL | > __GFP_ZERO); > if (!merged_hyp_pgd) { > kvm_err("Failed to allocate extra HYP pgd\n"); > @@ -1746,29 +1759,10 @@ int kvm_mmu_init(void) > } > __kvm_extend_hypmap(boot_hyp_pgd, hyp_pgd, merged_hyp_pgd, > hyp_idmap_start); > - return 0; > - } > - > - /* Map the very same page at the trampoline VA */ > - err = __create_hyp_mappings(boot_hyp_pgd, > - TRAMPOLINE_VA, TRAMPOLINE_VA + PAGE_SIZE, > - __phys_to_pfn(hyp_idmap_start), > - PAGE_HYP); > - if (err) { > - kvm_err("Failed to map trampoline @%lx into boot HYP pgd\n", > - TRAMPOLINE_VA); > - goto out; > - } > - > - /* Map the same page again into the runtime page tables */ > - err = __create_hyp_mappings(hyp_pgd, > - TRAMPOLINE_VA, TRAMPOLINE_VA + PAGE_SIZE, > - __phys_to_pfn(hyp_idmap_start), > - PAGE_HYP); > - if (err) { > - kvm_err("Failed to map trampoline @%lx into runtime HYP pgd\n", > - TRAMPOLINE_VA); > - goto out; > + } else { > + err = kvm_map_idmap_text(hyp_pgd); > + if (err) > + goto out;
Something I'm not clear on: how can we always have merged pgtables on 32-bit ARM at this point? why is there not a potential conflict at this point in the series between the runtime hyp mappings and the idmaps? Thanks, -Christoffer _______________________________________________ kvmarm mailing list [email protected] https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
