Commit 684019dd authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull EFI updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Allocate the E820 buffer before doing the
     GetMemoryMap/ExitBootServices dance so we don't run out of space

   - Clear EFI boot services mappings when freeing the memory

   - Harden efivars against callers that invoke it on non-EFI boots

   - Reduce the number of memblock reservations resulting from extensive
     use of the new efi_mem_reserve_persistent() API

   - Other assorted fixes and cleanups"

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/efi: Don't unmap EFI boot services code/data regions for EFI_OLD_MEMMAP and EFI_MIXED_MODE
  efi: Reduce the amount of memblock reservations for persistent allocations
  efi: Permit multiple entries in persistent memreserve data structure
  efi/libstub: Disable some warnings for x86{,_64}
  x86/efi: Move efi_<reserve/free>_boot_services() to arch/x86
  x86/efi: Unmap EFI boot services code/data regions from efi_pgd
  x86/mm/pageattr: Introduce helper function to unmap EFI boot services
  efi/fdt: Simplify the get_fdt() flow
  efi/fdt: Indentation fix
  firmware/efi: Add NULL pointer checks in efivars API functions
parents 792bf4d8 1debf095

arch/x86/include/asm/efi.h

+2 −0
Original line number Diff line number Diff line
@@ -141,6 +141,8 @@ extern int __init efi_reuse_config(u64 tables, int nr_tables); 
extern void efi_delete_dummy_variable(void);

extern void efi_switch_mm(struct mm_struct *mm);

extern void efi_recover_from_page_fault(unsigned long phys_addr);

extern void efi_free_boot_services(void);

extern void efi_reserve_boot_services(void);



struct efi_setup_data {

	u64 fw_vendor;

arch/x86/include/asm/pgtable_types.h

+6 −2
Original line number Diff line number Diff line
@@ -564,8 +564,12 @@ extern pte_t *lookup_address_in_pgd(pgd_t *pgd, unsigned long address, 
				    unsigned int *level);

extern pmd_t *lookup_pmd_address(unsigned long address);

extern phys_addr_t slow_virt_to_phys(void *__address);

extern int kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address,

				   unsigned numpages, unsigned long page_flags);

extern int __init kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn,

					  unsigned long address,

					  unsigned numpages,

					  unsigned long page_flags);

extern int __init kernel_unmap_pages_in_pgd(pgd_t *pgd, unsigned long address,

					    unsigned long numpages);

#endif	/* !__ASSEMBLY__ */



#endif /* _ASM_X86_PGTABLE_DEFS_H */

arch/x86/mm/pageattr.c

+38 −2
Original line number Diff line number Diff line
@@ -2346,7 +2346,7 @@ bool kernel_page_present(struct page *page) 


#endif /* CONFIG_DEBUG_PAGEALLOC */



int kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address,

int __init kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address,

				   unsigned numpages, unsigned long page_flags)

{

	int retval = -EINVAL;
@@ -2361,6 +2361,8 @@ int kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address, 
		.flags = 0,

	};



	WARN_ONCE(num_online_cpus() > 1, "Don't call after initializing SMP");



	if (!(__supported_pte_mask & _PAGE_NX))

		goto out;
@@ -2382,6 +2384,40 @@ out: 
	return retval;

}



/*

 * __flush_tlb_all() flushes mappings only on current CPU and hence this

 * function shouldn't be used in an SMP environment. Presently, it's used only

 * during boot (way before smp_init()) by EFI subsystem and hence is ok.

 */

int __init kernel_unmap_pages_in_pgd(pgd_t *pgd, unsigned long address,

				     unsigned long numpages)

{

	int retval;



	/*

	 * The typical sequence for unmapping is to find a pte through

	 * lookup_address_in_pgd() (ideally, it should never return NULL because

	 * the address is already mapped) and change it's protections. As pfn is

	 * the *target* of a mapping, it's not useful while unmapping.

	 */

	struct cpa_data cpa = {

		.vaddr		= &address,

		.pfn		= 0,

		.pgd		= pgd,

		.numpages	= numpages,

		.mask_set	= __pgprot(0),

		.mask_clr	= __pgprot(_PAGE_PRESENT | _PAGE_RW),

		.flags		= 0,

	};



	WARN_ONCE(num_online_cpus() > 1, "Don't call after initializing SMP");



	retval = __change_page_attr_set_clr(&cpa, 0);

	__flush_tlb_all();



	return retval;

}



/*

 * The testcases use internal knowledge of the implementation that shouldn't

 * be exposed to the rest of the kernel. Include these directly here.

arch/x86/platform/efi/efi.c

+2 −0
Original line number Diff line number Diff line
@@ -993,6 +993,8 @@ static void __init __efi_enter_virtual_mode(void) 
		panic("EFI call to SetVirtualAddressMap() failed!");

	}



	efi_free_boot_services();



	/*

	 * Now that EFI is in virtual mode, update the function

	 * pointers in the runtime service table to the new virtual addresses.

arch/x86/platform/efi/quirks.c

+41 −0
Original line number Diff line number Diff line
@@ -369,6 +369,40 @@ void __init efi_reserve_boot_services(void) 
	}

}



/*

 * Apart from having VA mappings for EFI boot services code/data regions,

 * (duplicate) 1:1 mappings were also created as a quirk for buggy firmware. So,

 * unmap both 1:1 and VA mappings.

 */

static void __init efi_unmap_pages(efi_memory_desc_t *md)

{

	pgd_t *pgd = efi_mm.pgd;

	u64 pa = md->phys_addr;

	u64 va = md->virt_addr;



	/*

	 * To Do: Remove this check after adding functionality to unmap EFI boot

	 * services code/data regions from direct mapping area because

	 * "efi=old_map" maps EFI regions in swapper_pg_dir.

	 */

	if (efi_enabled(EFI_OLD_MEMMAP))

		return;



	/*

	 * EFI mixed mode has all RAM mapped to access arguments while making

	 * EFI runtime calls, hence don't unmap EFI boot services code/data

	 * regions.

	 */

	if (!efi_is_native())

		return;



	if (kernel_unmap_pages_in_pgd(pgd, pa, md->num_pages))

		pr_err("Failed to unmap 1:1 mapping for 0x%llx\n", pa);



	if (kernel_unmap_pages_in_pgd(pgd, va, md->num_pages))

		pr_err("Failed to unmap VA mapping for 0x%llx\n", va);

}



void __init efi_free_boot_services(void)

{

	phys_addr_t new_phys, new_size;
@@ -393,6 +427,13 @@ void __init efi_free_boot_services(void) 
			continue;

		}



		/*

		 * Before calling set_virtual_address_map(), EFI boot services

		 * code/data regions were mapped as a quirk for buggy firmware.

		 * Unmap them from efi_pgd before freeing them up.

		 */

		efi_unmap_pages(md);



		/*

		 * Nasty quirk: if all sub-1MB memory is used for boot

		 * services, we can get here without having allocated the

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