| Message ID | 1469208745-6693-2-git-send-email-ard.biesheuvel@linaro.org |
|---|---|
| State | Accepted |
| Commit | 258a1605c78878ada00417de4840c4c427673ffa |
| Headers | show |
Hi Ard, On Fri, Jul 22, 2016 at 07:32:24PM +0200, Ard Biesheuvel wrote: > The only purpose served by create_mapping_late() is to remap the already > mapped .text and .rodata kernel segments with read-only permissions. Since > we no longer allow block mappings to be split or merged, > create_mapping_late() should not pass an allocation function pointer into > __create_pgd_mapping(). So pass NULL instead. > > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> > --- > arch/arm64/mm/mmu.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c > index a96a2413fa18..33f36cede02d 100644 > --- a/arch/arm64/mm/mmu.c > +++ b/arch/arm64/mm/mmu.c > @@ -312,7 +312,7 @@ static void create_mapping_late(phys_addr_t phys, unsigned long virt, > } > > __create_pgd_mapping(init_mm.pgd, phys, virt, size, prot, > - late_pgtable_alloc, !debug_pagealloc_enabled()); > + NULL, !debug_pagealloc_enabled()); > } How about we drop the __init marker from create_mapping_noalloc(), and update the callers in mark_rodata_ro() to use that, so that we can drop create_mapping_late() entirely. Other than the __init marker and name, create_mapping_late() and create_mapping_noalloc() would be identical after this change, and the naming of create_mapping_noalloc() does better describe what we're trying to achieve in mark_rodata_ro(). Thanks, Mark. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
> On 25 jul. 2016, at 15:46, Mark Rutland <mark.rutland@arm.com> wrote: > > Hi Ard, > >> On Fri, Jul 22, 2016 at 07:32:24PM +0200, Ard Biesheuvel wrote: >> The only purpose served by create_mapping_late() is to remap the already >> mapped .text and .rodata kernel segments with read-only permissions. Since >> we no longer allow block mappings to be split or merged, >> create_mapping_late() should not pass an allocation function pointer into >> __create_pgd_mapping(). So pass NULL instead. >> >> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> >> --- >> arch/arm64/mm/mmu.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c >> index a96a2413fa18..33f36cede02d 100644 >> --- a/arch/arm64/mm/mmu.c >> +++ b/arch/arm64/mm/mmu.c >> @@ -312,7 +312,7 @@ static void create_mapping_late(phys_addr_t phys, unsigned long virt, >> } >> >> __create_pgd_mapping(init_mm.pgd, phys, virt, size, prot, >> - late_pgtable_alloc, !debug_pagealloc_enabled()); >> + NULL, !debug_pagealloc_enabled()); >> } > > How about we drop the __init marker from create_mapping_noalloc(), and > update the callers in mark_rodata_ro() to use that, so that we can drop > create_mapping_late() entirely. > > Other than the __init marker and name, create_mapping_late() and > create_mapping_noalloc() would be identical after this change, and the > naming of create_mapping_noalloc() does better describe what we're > trying to achieve in mark_rodata_ro(). > Not entirely. The _late() variant should map down to pages if the first mapping was mapped down to pages as well. The _noalloc() variant may end attempting to merge regions _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
On Mon, Jul 25, 2016 at 04:10:50PM +0200, Ard Biesheuvel wrote: > > On 25 jul. 2016, at 15:46, Mark Rutland <mark.rutland@arm.com> wrote: > > How about we drop the __init marker from create_mapping_noalloc(), and > > update the callers in mark_rodata_ro() to use that, so that we can drop > > create_mapping_late() entirely. > > > > Other than the __init marker and name, create_mapping_late() and > > create_mapping_noalloc() would be identical after this change, and the > > naming of create_mapping_noalloc() does better describe what we're > > trying to achieve in mark_rodata_ro(). > > Not entirely. The _late() variant should map down to pages if the > first mapping was mapped down to pages as well. The _noalloc() variant > may end attempting to merge regions Ah, I was comparing against mainline rather than the arm64 for-next/core branch with the recent rework. Sorry for the noise. Given that, FWIW: Acked-by: Mark Rutland <mark.rutland@arm.com> Mark. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index a96a2413fa18..33f36cede02d 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -312,7 +312,7 @@ static void create_mapping_late(phys_addr_t phys, unsigned long virt, } __create_pgd_mapping(init_mm.pgd, phys, virt, size, prot, - late_pgtable_alloc, !debug_pagealloc_enabled()); + NULL, !debug_pagealloc_enabled()); } static void __init __map_memblock(pgd_t *pgd, phys_addr_t start, phys_addr_t end)
The only purpose served by create_mapping_late() is to remap the already mapped .text and .rodata kernel segments with read-only permissions. Since we no longer allow block mappings to be split or merged, create_mapping_late() should not pass an allocation function pointer into __create_pgd_mapping(). So pass NULL instead. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> --- arch/arm64/mm/mmu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- 2.7.4 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel