| Message ID | 1487498660-16600-6-git-send-email-hoeun.ryu@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 19 February 2017 at 10:04, Hoeun Ryu <hoeun.ryu@gmail.com> wrote: > Memory attribute for `__ro_mostly_after_init` section should be changed > via set_memory_rw/ro that doesn't work against vm areas which don't have > VM_ALLOC. This is for a good reason: VMALLOC regions are guaranteed to be mapped down to pages, which is the only thing set_memory_rX() supports. On arm64, kernel segments may be mapped using contiguous page mappings or block mappings, which cannot be modified like this. > Add this function to map `__ro_mostly_after_init` section with > VM_ALLOC flag set in map_kernel. > If we add this functionality, I'd rather we have a special handler for the __ro_mostly_after_init section and not use set_memory_rX(). > Signed-off-by: Hoeun Ryu <hoeun.ryu@gmail.com> > --- > arch/arm64/mm/mmu.c | 14 +++++++++++--- > 1 file changed, 11 insertions(+), 3 deletions(-) > > diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c > index b805c01..91271b1 100644 > --- a/arch/arm64/mm/mmu.c > +++ b/arch/arm64/mm/mmu.c > @@ -444,8 +444,10 @@ void mark_rodata_ro(void) > debug_checkwx(); > } > > -static void __init map_kernel_segment(pgd_t *pgd, void *va_start, void *va_end, > - pgprot_t prot, struct vm_struct *vma) > +static void __init __map_kernel_segment(pgd_t *pgd, > + void *va_start, void *va_end, > + pgprot_t prot, struct vm_struct *vma, > + unsigned long flags) > { > phys_addr_t pa_start = __pa_symbol(va_start); > unsigned long size = va_end - va_start; > @@ -459,12 +461,18 @@ static void __init map_kernel_segment(pgd_t *pgd, void *va_start, void *va_end, > vma->addr = va_start; > vma->phys_addr = pa_start; > vma->size = size; > - vma->flags = VM_MAP; > + vma->flags = flags; > vma->caller = __builtin_return_address(0); > > vm_area_add_early(vma); > } > > +static void __init map_kernel_segment(pgd_t *pgd, void *va_start, void *va_end, > + pgprot_t prot, struct vm_struct *vma) > +{ > + return __map_kernel_segment(pgd, va_start, va_end, prot, vma, VM_MAP); > +} > + > /* > * Create fine-grained mappings for the kernel. > */ > -- > 2.7.4 >
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index b805c01..91271b1 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -444,8 +444,10 @@ void mark_rodata_ro(void) debug_checkwx(); } -static void __init map_kernel_segment(pgd_t *pgd, void *va_start, void *va_end, - pgprot_t prot, struct vm_struct *vma) +static void __init __map_kernel_segment(pgd_t *pgd, + void *va_start, void *va_end, + pgprot_t prot, struct vm_struct *vma, + unsigned long flags) { phys_addr_t pa_start = __pa_symbol(va_start); unsigned long size = va_end - va_start; @@ -459,12 +461,18 @@ static void __init map_kernel_segment(pgd_t *pgd, void *va_start, void *va_end, vma->addr = va_start; vma->phys_addr = pa_start; vma->size = size; - vma->flags = VM_MAP; + vma->flags = flags; vma->caller = __builtin_return_address(0); vm_area_add_early(vma); } +static void __init map_kernel_segment(pgd_t *pgd, void *va_start, void *va_end, + pgprot_t prot, struct vm_struct *vma) +{ + return __map_kernel_segment(pgd, va_start, va_end, prot, vma, VM_MAP); +} + /* * Create fine-grained mappings for the kernel. */
Memory attribute for `__ro_mostly_after_init` section should be changed via set_memory_rw/ro that doesn't work against vm areas which don't have VM_ALLOC. Add this function to map `__ro_mostly_after_init` section with VM_ALLOC flag set in map_kernel. Signed-off-by: Hoeun Ryu <hoeun.ryu@gmail.com> --- arch/arm64/mm/mmu.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-)