On Mon, Aug 22, 2016 at 05:37:38PM -0500, Tom Lendacky wrote:
> BOOT data (such as EFI related data) is not encyrpted when the system is
> booted and needs to be accessed as non-encrypted. Add support to the
> early_memremap API to identify the type of data being accessed so that
> the proper encryption attribute can be applied. Currently, two types
> of data are defined, KERNEL_DATA and BOOT_DATA.
>
> Signed-off-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
> ---
...
> diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
> index 031db21..e3bdc5a 100644
> --- a/arch/x86/mm/ioremap.c
> +++ b/arch/x86/mm/ioremap.c
> @@ -419,6 +419,25 @@ void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr)
> iounmap((void __iomem *)((unsigned long)addr & PAGE_MASK));
> }
>
> +/*
> + * Architecure override of __weak function to adjust the protection attributes
> + * used when remapping memory.
> + */
> +pgprot_t __init early_memremap_pgprot_adjust(resource_size_t phys_addr,
> + unsigned long size,
> + enum memremap_owner owner,
> + pgprot_t prot)
> +{
> + /*
> + * If memory encryption is enabled and BOOT_DATA is being mapped
> + * then remove the encryption bit.
> + */
> + if (_PAGE_ENC && (owner == BOOT_DATA))
> + prot = __pgprot(pgprot_val(prot) & ~_PAGE_ENC);
> +
> + return prot;
> +}
> +
Hmm, so AFAICT, only arch/x86/xen needs KERNEL_DATA and everything else
is BOOT_DATA.
So instead of touching so many files and changing early_memremap(),
why can't you remove _PAGE_ENC by default on x86 and define a specific
early_memremap() for arch/x86/xen/ which you call there?
That would make this patch soo much smaller and the change simpler.
...
> diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
> index 5a2631a..f9286c6 100644
> --- a/drivers/firmware/efi/efi.c
> +++ b/drivers/firmware/efi/efi.c
> @@ -386,7 +386,7 @@ int __init efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
> * So just always get our own virtual map on the CPU.
> *
> */
> - md = early_memremap(p, sizeof (*md));
> + md = early_memremap(p, sizeof (*md), BOOT_DATA);
WARNING: space prohibited between function name and open parenthesis '('
#432: FILE: drivers/firmware/efi/efi.c:389:
+ md = early_memremap(p, sizeof (*md), BOOT_DATA);
Please integrate checkpatch.pl into your workflow so that you can catch
small style nits like this. And don't take its output too seriously... :-)
> if (!md) {
> pr_err_once("early_memremap(%pa, %zu) failed.\n",
> &p, sizeof (*md));
> @@ -501,7 +501,8 @@ int __init efi_config_parse_tables(void *config_tables, int count, int sz,
> if (efi.properties_table != EFI_INVALID_TABLE_ADDR) {
> efi_properties_table_t *tbl;
>
> - tbl = early_memremap(efi.properties_table, sizeof(*tbl));
> + tbl = early_memremap(efi.properties_table, sizeof(*tbl),
> + BOOT_DATA);
> if (tbl == NULL) {
> pr_err("Could not map Properties table!\n");
> return -ENOMEM;
--
Regards/Gruss,
Boris.
ECO tip #101: Trim your mails when you reply.
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