There should be no reason for mapping the HYP text read/write. As such, let's have a new set of flags (PAGE_HYP_EXEC) that allows execution, but makes the page as read-only, and update the two call sites that deal with mapping code.
Signed-off-by: Marc Zyngier <[email protected]> --- arch/arm/include/asm/pgtable.h | 1 + arch/arm/kvm/arm.c | 2 +- arch/arm/kvm/mmu.c | 2 +- arch/arm64/include/asm/pgtable-prot.h | 1 + 4 files changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h index f332087..7487bf9 100644 --- a/arch/arm/include/asm/pgtable.h +++ b/arch/arm/include/asm/pgtable.h @@ -98,6 +98,7 @@ extern pgprot_t pgprot_s2_device; #define PAGE_KERNEL _MOD_PROT(pgprot_kernel, L_PTE_XN) #define PAGE_KERNEL_EXEC pgprot_kernel #define PAGE_HYP _MOD_PROT(pgprot_kernel, L_PTE_HYP) +#define PAGE_HYP_EXEC _MOD_PROT(pgprot_kernel, L_PTE_HYP | L_PTE_RDONLY) #define PAGE_HYP_RO _MOD_PROT(pgprot_kernel, L_PTE_HYP | L_PTE_RDONLY | L_PTE_XN) #define PAGE_HYP_DEVICE _MOD_PROT(pgprot_hyp_device, L_PTE_HYP) #define PAGE_S2 _MOD_PROT(pgprot_s2, L_PTE_S2_RDONLY) diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 0b5099f..d7bf2dd 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -1285,7 +1285,7 @@ static int init_hyp_mode(void) * Map the Hyp-code called directly from the host */ err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start), - kvm_ksym_ref(__hyp_text_end), PAGE_HYP); + kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC); if (err) { kvm_err("Cannot map world-switch code\n"); goto out_err; diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index 6023abd..8a0aa37 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -1687,7 +1687,7 @@ static int kvm_map_idmap_text(pgd_t *pgd) err = __create_hyp_mappings(pgd, hyp_idmap_start, hyp_idmap_end, __phys_to_pfn(hyp_idmap_start), - PAGE_HYP); + PAGE_HYP_EXEC); if (err) kvm_err("Failed to idmap %lx-%lx\n", hyp_idmap_start, hyp_idmap_end); diff --git a/arch/arm64/include/asm/pgtable-prot.h b/arch/arm64/include/asm/pgtable-prot.h index 88db58c..3802048 100644 --- a/arch/arm64/include/asm/pgtable-prot.h +++ b/arch/arm64/include/asm/pgtable-prot.h @@ -56,6 +56,7 @@ #define PAGE_KERNEL_EXEC_CONT __pgprot(_PAGE_DEFAULT | PTE_UXN | PTE_DIRTY | PTE_WRITE | PTE_CONT) #define PAGE_HYP __pgprot(_PAGE_DEFAULT | PTE_HYP) +#define PAGE_HYP_EXEC __pgprot(_PAGE_DEFAULT | PTE_HYP | PTE_RDONLY) #define PAGE_HYP_RO __pgprot(_PAGE_DEFAULT | PTE_HYP | PTE_RDONLY | PTE_HYP_XN) #define PAGE_HYP_DEVICE __pgprot(PROT_DEVICE_nGnRE | PTE_HYP) -- 2.1.4 _______________________________________________ kvmarm mailing list [email protected] https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
