| Message ID | 20201119162543.78001-2-dbrazdil@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | kvm: arm64: Fix up hyp relocations | expand |
On Thu, 19 Nov 2020 at 17:25, David Brazdil <dbrazdil@google.com> wrote: > > We will need to recognize pointers in .rodata specific to hyp, Why? > so > establish a .hyp.rodata ELF section. Merge it with the existing > .hyp.data..ro_after_init as they are treated the same at runtime. > Does this mean HYP .text, .rodata etc are all writable some time after the kernel .text/.rodata have been mapped read-only? That is not a problem per se, but it deserves being called out. > Signed-off-by: David Brazdil <dbrazdil@google.com> > --- > arch/arm64/include/asm/sections.h | 2 +- > arch/arm64/kernel/vmlinux.lds.S | 7 ++++--- > arch/arm64/kvm/arm.c | 7 +++---- > arch/arm64/kvm/hyp/nvhe/hyp.lds.S | 1 + > 4 files changed, 9 insertions(+), 8 deletions(-) > > diff --git a/arch/arm64/include/asm/sections.h b/arch/arm64/include/asm/sections.h > index 8ff579361731..a6f3557d1ab2 100644 > --- a/arch/arm64/include/asm/sections.h > +++ b/arch/arm64/include/asm/sections.h > @@ -11,7 +11,7 @@ extern char __alt_instructions[], __alt_instructions_end[]; > extern char __hibernate_exit_text_start[], __hibernate_exit_text_end[]; > extern char __hyp_idmap_text_start[], __hyp_idmap_text_end[]; > extern char __hyp_text_start[], __hyp_text_end[]; > -extern char __hyp_data_ro_after_init_start[], __hyp_data_ro_after_init_end[]; > +extern char __hyp_rodata_start[], __hyp_rodata_end[]; > extern char __idmap_text_start[], __idmap_text_end[]; > extern char __initdata_begin[], __initdata_end[]; > extern char __inittext_begin[], __inittext_end[]; > diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S > index 4382b5d0645d..6f2fd9734d63 100644 > --- a/arch/arm64/kernel/vmlinux.lds.S > +++ b/arch/arm64/kernel/vmlinux.lds.S > @@ -31,10 +31,11 @@ jiffies = jiffies_64; > __stop___kvm_ex_table = .; > > #define HYPERVISOR_DATA_SECTIONS \ > - HYP_SECTION_NAME(.data..ro_after_init) : { \ > - __hyp_data_ro_after_init_start = .; \ > + HYP_SECTION_NAME(.rodata) : { \ > + __hyp_rodata_start = .; \ > *(HYP_SECTION_NAME(.data..ro_after_init)) \ > - __hyp_data_ro_after_init_end = .; \ > + *(HYP_SECTION_NAME(.rodata)) \ > + __hyp_rodata_end = .; \ > } > > #define HYPERVISOR_PERCPU_SECTION \ > diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c > index d6d5211653b7..119c97e8900a 100644 > --- a/arch/arm64/kvm/arm.c > +++ b/arch/arm64/kvm/arm.c > @@ -1688,11 +1688,10 @@ static int init_hyp_mode(void) > goto out_err; > } > > - err = create_hyp_mappings(kvm_ksym_ref(__hyp_data_ro_after_init_start), > - kvm_ksym_ref(__hyp_data_ro_after_init_end), > - PAGE_HYP_RO); > + err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start), > + kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO); > if (err) { > - kvm_err("Cannot map .hyp.data..ro_after_init section\n"); > + kvm_err("Cannot map .hyp.rodata section\n"); > goto out_err; > } > > diff --git a/arch/arm64/kvm/hyp/nvhe/hyp.lds.S b/arch/arm64/kvm/hyp/nvhe/hyp.lds.S > index 5d76ff2ba63e..b0789183d49d 100644 > --- a/arch/arm64/kvm/hyp/nvhe/hyp.lds.S > +++ b/arch/arm64/kvm/hyp/nvhe/hyp.lds.S > @@ -17,4 +17,5 @@ SECTIONS { > PERCPU_INPUT(L1_CACHE_BYTES) > } > HYP_SECTION(.data..ro_after_init) > + HYP_SECTION(.rodata) > } > -- > 2.29.2.299.gdc1121823c-goog >
diff --git a/arch/arm64/include/asm/sections.h b/arch/arm64/include/asm/sections.h index 8ff579361731..a6f3557d1ab2 100644 --- a/arch/arm64/include/asm/sections.h +++ b/arch/arm64/include/asm/sections.h @@ -11,7 +11,7 @@ extern char __alt_instructions[], __alt_instructions_end[]; extern char __hibernate_exit_text_start[], __hibernate_exit_text_end[]; extern char __hyp_idmap_text_start[], __hyp_idmap_text_end[]; extern char __hyp_text_start[], __hyp_text_end[]; -extern char __hyp_data_ro_after_init_start[], __hyp_data_ro_after_init_end[]; +extern char __hyp_rodata_start[], __hyp_rodata_end[]; extern char __idmap_text_start[], __idmap_text_end[]; extern char __initdata_begin[], __initdata_end[]; extern char __inittext_begin[], __inittext_end[]; diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S index 4382b5d0645d..6f2fd9734d63 100644 --- a/arch/arm64/kernel/vmlinux.lds.S +++ b/arch/arm64/kernel/vmlinux.lds.S @@ -31,10 +31,11 @@ jiffies = jiffies_64; __stop___kvm_ex_table = .; #define HYPERVISOR_DATA_SECTIONS \ - HYP_SECTION_NAME(.data..ro_after_init) : { \ - __hyp_data_ro_after_init_start = .; \ + HYP_SECTION_NAME(.rodata) : { \ + __hyp_rodata_start = .; \ *(HYP_SECTION_NAME(.data..ro_after_init)) \ - __hyp_data_ro_after_init_end = .; \ + *(HYP_SECTION_NAME(.rodata)) \ + __hyp_rodata_end = .; \ } #define HYPERVISOR_PERCPU_SECTION \ diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index d6d5211653b7..119c97e8900a 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1688,11 +1688,10 @@ static int init_hyp_mode(void) goto out_err; } - err = create_hyp_mappings(kvm_ksym_ref(__hyp_data_ro_after_init_start), - kvm_ksym_ref(__hyp_data_ro_after_init_end), - PAGE_HYP_RO); + err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start), + kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO); if (err) { - kvm_err("Cannot map .hyp.data..ro_after_init section\n"); + kvm_err("Cannot map .hyp.rodata section\n"); goto out_err; } diff --git a/arch/arm64/kvm/hyp/nvhe/hyp.lds.S b/arch/arm64/kvm/hyp/nvhe/hyp.lds.S index 5d76ff2ba63e..b0789183d49d 100644 --- a/arch/arm64/kvm/hyp/nvhe/hyp.lds.S +++ b/arch/arm64/kvm/hyp/nvhe/hyp.lds.S @@ -17,4 +17,5 @@ SECTIONS { PERCPU_INPUT(L1_CACHE_BYTES) } HYP_SECTION(.data..ro_after_init) + HYP_SECTION(.rodata) }
We will need to recognize pointers in .rodata specific to hyp, so establish a .hyp.rodata ELF section. Merge it with the existing .hyp.data..ro_after_init as they are treated the same at runtime. Signed-off-by: David Brazdil <dbrazdil@google.com> --- arch/arm64/include/asm/sections.h | 2 +- arch/arm64/kernel/vmlinux.lds.S | 7 ++++--- arch/arm64/kvm/arm.c | 7 +++---- arch/arm64/kvm/hyp/nvhe/hyp.lds.S | 1 + 4 files changed, 9 insertions(+), 8 deletions(-)