| Message ID | 1448276951-13335-1-git-send-email-mark.rutland@arm.com |
|---|---|
| State | New |
| Headers | show |
On Mon, Nov 23, 2015 at 11:09:11AM +0000, Mark Rutland wrote: > The kernel may use a page granularity of 4K, 16K, or 64K depending on > configuration. > > When mapping EFI runtime regions, we use memrange_efi_to_native to round > the physical base address of a region down to a kernel page boundary, > and round the size up to a kernel page boundary, adding the residue left > over from rounding down the physical base address. We do not round down > the virtual base address. > > In __create_mapping we account for the offset of the virtual base from a > granule boundary, adding the residue to the size before rounding the > base down to said granule boundary. > > Thus we account for the residue twice, and when the residue is non-zero > will cause __create_mapping to map an additional page at the end of the > region. Depending on the memory map, this page may be in a region we are > not intended/permitted to map, or may clash with a different region that > we wish to map. In typical cases, mapping the next item in the memory > map will overwrite the erroneously created entry, as we sort the memory > map in the stub. > > As __create_mapping can cope with base addresses which are not page > aligned, we can instead rely on it to map the region appropriately, and > simplify efi_virtmap_init by removing the unnecessary code. > > Signed-off-by: Mark Rutland <mark.rutland@arm.com> > Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> > Cc: Catalin Marinas <catalin.marinas@arm.com> > Cc: Leif Lindholm <leif.lindholm@linaro.org> > Cc: Will Deacon <will.deacon@arm.com> Patch applied. Thanks. -- Catalin _______________________________________________ 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/kernel/efi.c b/arch/arm64/kernel/efi.c index fc5508e..fe7cd1a 100644 --- a/arch/arm64/kernel/efi.c +++ b/arch/arm64/kernel/efi.c @@ -227,7 +227,6 @@ static bool __init efi_virtmap_init(void) init_new_context(NULL, &efi_mm); for_each_efi_memory_desc(&memmap, md) { - u64 paddr, npages, size; pgprot_t prot; if (!(md->attribute & EFI_MEMORY_RUNTIME)) @@ -235,11 +234,6 @@ static bool __init efi_virtmap_init(void) if (md->virt_addr == 0) return false; - paddr = md->phys_addr; - npages = md->num_pages; - memrange_efi_to_native(&paddr, &npages); - size = npages << PAGE_SHIFT; - pr_info(" EFI remap 0x%016llx => %p\n", md->phys_addr, (void *)md->virt_addr); @@ -256,7 +250,8 @@ static bool __init efi_virtmap_init(void) else prot = PAGE_KERNEL; - create_pgd_mapping(&efi_mm, paddr, md->virt_addr, size, + create_pgd_mapping(&efi_mm, md->phys_addr, md->virt_addr, + md->num_pages << EFI_PAGE_SHIFT, __pgprot(pgprot_val(prot) | PTE_NG)); } return true;