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authorLinus Torvalds <torvalds@linux-foundation.org>2020-03-30 16:13:08 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-03-30 16:13:08 -0700
commita776c270a0b2fad6715cb714187e4290cadb9237 (patch)
tree6221a924a1a388a791c33a9223d62991b18b6515 /drivers/firmware/efi/libstub/arm-stub.c
parent7c4fa150714fb319d4e2bb2303ebbd7307b0fb6d (diff)
parent594e576d4b93b8cda3247542366b47e1b2ddc4dc (diff)
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 EFI changes in this cycle are much larger than usual, for two (positive) reasons: - The GRUB project is showing signs of life again, resulting in the introduction of the generic Linux/UEFI boot protocol, instead of x86 specific hacks which are increasingly difficult to maintain. There's hope that all future extensions will now go through that boot protocol. - Preparatory work for RISC-V EFI support. The main changes are: - Boot time GDT handling changes - Simplify handling of EFI properties table on arm64 - Generic EFI stub cleanups, to improve command line handling, file I/O, memory allocation, etc. - Introduce a generic initrd loading method based on calling back into the firmware, instead of relying on the x86 EFI handover protocol or device tree. - Introduce a mixed mode boot method that does not rely on the x86 EFI handover protocol either, and could potentially be adopted by other architectures (if another one ever surfaces where one execution mode is a superset of another) - Clean up the contents of 'struct efi', and move out everything that doesn't need to be stored there. - Incorporate support for UEFI spec v2.8A changes that permit firmware implementations to return EFI_UNSUPPORTED from UEFI runtime services at OS runtime, and expose a mask of which ones are supported or unsupported via a configuration table. - Partial fix for the lack of by-VA cache maintenance in the decompressor on 32-bit ARM. - Changes to load device firmware from EFI boot service memory regions - Various documentation updates and minor code cleanups and fixes" * 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (114 commits) efi/libstub/arm: Fix spurious message that an initrd was loaded efi/libstub/arm64: Avoid image_base value from efi_loaded_image partitions/efi: Fix partition name parsing in GUID partition entry efi/x86: Fix cast of image argument efi/libstub/x86: Use ULONG_MAX as upper bound for all allocations efi: Fix a mistype in comments mentioning efivar_entry_iter_begin() efi/libstub: Avoid linking libstub/lib-ksyms.o into vmlinux efi/x86: Preserve %ebx correctly in efi_set_virtual_address_map() efi/x86: Ignore the memory attributes table on i386 efi/x86: Don't relocate the kernel unless necessary efi/x86: Remove extra headroom for setup block efi/x86: Add kernel preferred address to PE header efi/x86: Decompress at start of PE image load address x86/boot/compressed/32: Save the output address instead of recalculating it efi/libstub/x86: Deal with exit() boot service returning x86/boot: Use unsigned comparison for addresses efi/x86: Avoid using code32_start efi/x86: Make efi32_pe_entry() more readable efi/x86: Respect 32-bit ABI in efi32_pe_entry() efi/x86: Annotate the LOADED_IMAGE_PROTOCOL_GUID with SYM_DATA ...
Diffstat (limited to 'drivers/firmware/efi/libstub/arm-stub.c')
-rw-r--r--drivers/firmware/efi/libstub/arm-stub.c193
1 files changed, 100 insertions, 93 deletions
diff --git a/drivers/firmware/efi/libstub/arm-stub.c b/drivers/firmware/efi/libstub/arm-stub.c
index 7bbef4a67350..99a5cde7c2d8 100644
--- a/drivers/firmware/efi/libstub/arm-stub.c
+++ b/drivers/firmware/efi/libstub/arm-stub.c
@@ -10,7 +10,7 @@
*/
#include <linux/efi.h>
-#include <linux/sort.h>
+#include <linux/libfdt.h>
#include <asm/efi.h>
#include "efistub.h"
@@ -36,6 +36,7 @@
#endif
static u64 virtmap_base = EFI_RT_VIRTUAL_BASE;
+static bool __efistub_global flat_va_mapping;
static efi_system_table_t *__efistub_global sys_table;
@@ -87,6 +88,39 @@ void install_memreserve_table(void)
pr_efi_err("Failed to install memreserve config table!\n");
}
+static unsigned long get_dram_base(void)
+{
+ efi_status_t status;
+ unsigned long map_size, buff_size;
+ unsigned long membase = EFI_ERROR;
+ struct efi_memory_map map;
+ efi_memory_desc_t *md;
+ struct efi_boot_memmap boot_map;
+
+ boot_map.map = (efi_memory_desc_t **)&map.map;
+ boot_map.map_size = &map_size;
+ boot_map.desc_size = &map.desc_size;
+ boot_map.desc_ver = NULL;
+ boot_map.key_ptr = NULL;
+ boot_map.buff_size = &buff_size;
+
+ status = efi_get_memory_map(&boot_map);
+ if (status != EFI_SUCCESS)
+ return membase;
+
+ map.map_end = map.map + map_size;
+
+ for_each_efi_memory_desc_in_map(&map, md) {
+ if (md->attribute & EFI_MEMORY_WB) {
+ if (membase > md->phys_addr)
+ membase = md->phys_addr;
+ }
+ }
+
+ efi_bs_call(free_pool, map.map);
+
+ return membase;
+}
/*
* This function handles the architcture specific differences between arm and
@@ -100,38 +134,46 @@ efi_status_t handle_kernel_image(unsigned long *image_addr,
unsigned long *reserve_size,
unsigned long dram_base,
efi_loaded_image_t *image);
+
+asmlinkage void __noreturn efi_enter_kernel(unsigned long entrypoint,
+ unsigned long fdt_addr,
+ unsigned long fdt_size);
+
/*
* EFI entry point for the arm/arm64 EFI stubs. This is the entrypoint
* that is described in the PE/COFF header. Most of the code is the same
* for both archictectures, with the arch-specific code provided in the
* handle_kernel_image() function.
*/
-unsigned long efi_entry(void *handle, efi_system_table_t *sys_table_arg,
- unsigned long *image_addr)
+efi_status_t efi_entry(efi_handle_t handle, efi_system_table_t *sys_table_arg)
{
efi_loaded_image_t *image;
efi_status_t status;
+ unsigned long image_addr;
unsigned long image_size = 0;
unsigned long dram_base;
/* addr/point and size pairs for memory management*/
- unsigned long initrd_addr;
- u64 initrd_size = 0;
+ unsigned long initrd_addr = 0;
+ unsigned long initrd_size = 0;
unsigned long fdt_addr = 0; /* Original DTB */
unsigned long fdt_size = 0;
char *cmdline_ptr = NULL;
int cmdline_size = 0;
- unsigned long new_fdt_addr;
efi_guid_t loaded_image_proto = LOADED_IMAGE_PROTOCOL_GUID;
unsigned long reserve_addr = 0;
unsigned long reserve_size = 0;
enum efi_secureboot_mode secure_boot;
struct screen_info *si;
+ efi_properties_table_t *prop_tbl;
+ unsigned long max_addr;
sys_table = sys_table_arg;
/* Check if we were booted by the EFI firmware */
- if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
+ if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
+ status = EFI_INVALID_PARAMETER;
goto fail;
+ }
status = check_platform_features();
if (status != EFI_SUCCESS)
@@ -152,6 +194,7 @@ unsigned long efi_entry(void *handle, efi_system_table_t *sys_table_arg,
dram_base = get_dram_base();
if (dram_base == EFI_ERROR) {
pr_efi_err("Failed to find DRAM base\n");
+ status = EFI_LOAD_ERROR;
goto fail;
}
@@ -160,9 +203,10 @@ unsigned long efi_entry(void *handle, efi_system_table_t *sys_table_arg,
* protocol. We are going to copy the command line into the
* device tree, so this can be allocated anywhere.
*/
- cmdline_ptr = efi_convert_cmdline(image, &cmdline_size);
+ cmdline_ptr = efi_convert_cmdline(image, &cmdline_size, ULONG_MAX);
if (!cmdline_ptr) {
pr_efi_err("getting command line via LOADED_IMAGE_PROTOCOL\n");
+ status = EFI_OUT_OF_RESOURCES;
goto fail;
}
@@ -178,7 +222,7 @@ unsigned long efi_entry(void *handle, efi_system_table_t *sys_table_arg,
si = setup_graphics();
- status = handle_kernel_image(image_addr, &image_size,
+ status = handle_kernel_image(&image_addr, &image_size,
&reserve_addr,
&reserve_size,
dram_base, image);
@@ -204,8 +248,7 @@ unsigned long efi_entry(void *handle, efi_system_table_t *sys_table_arg,
if (strstr(cmdline_ptr, "dtb="))
pr_efi("Ignoring DTB from command line.\n");
} else {
- status = handle_cmdline_files(image, cmdline_ptr, "dtb=",
- ~0UL, &fdt_addr, &fdt_size);
+ status = efi_load_dtb(image, &fdt_addr, &fdt_size);
if (status != EFI_SUCCESS) {
pr_efi_err("Failed to load device tree!\n");
@@ -225,18 +268,38 @@ unsigned long efi_entry(void *handle, efi_system_table_t *sys_table_arg,
if (!fdt_addr)
pr_efi("Generating empty DTB\n");
- status = handle_cmdline_files(image, cmdline_ptr, "initrd=",
- efi_get_max_initrd_addr(dram_base,
- *image_addr),
- (unsigned long *)&initrd_addr,
- (unsigned long *)&initrd_size);
- if (status != EFI_SUCCESS)
- pr_efi_err("Failed initrd from command line!\n");
+ if (!noinitrd()) {
+ max_addr = efi_get_max_initrd_addr(dram_base, image_addr);
+ status = efi_load_initrd_dev_path(&initrd_addr, &initrd_size,
+ max_addr);
+ if (status == EFI_SUCCESS) {
+ pr_efi("Loaded initrd from LINUX_EFI_INITRD_MEDIA_GUID device path\n");
+ } else if (status == EFI_NOT_FOUND) {
+ status = efi_load_initrd(image, &initrd_addr, &initrd_size,
+ ULONG_MAX, max_addr);
+ if (status == EFI_SUCCESS && initrd_size > 0)
+ pr_efi("Loaded initrd from command line option\n");
+ }
+ if (status != EFI_SUCCESS)
+ pr_efi_err("Failed to load initrd!\n");
+ }
efi_random_get_seed();
+ /*
+ * If the NX PE data feature is enabled in the properties table, we
+ * should take care not to create a virtual mapping that changes the
+ * relative placement of runtime services code and data regions, as
+ * they may belong to the same PE/COFF executable image in memory.
+ * The easiest way to achieve that is to simply use a 1:1 mapping.
+ */
+ prop_tbl = get_efi_config_table(EFI_PROPERTIES_TABLE_GUID);
+ flat_va_mapping = prop_tbl &&
+ (prop_tbl->memory_protection_attribute &
+ EFI_PROPERTIES_RUNTIME_MEMORY_PROTECTION_NON_EXECUTABLE_PE_DATA);
+
/* hibernation expects the runtime regions to stay in the same place */
- if (!IS_ENABLED(CONFIG_HIBERNATION) && !nokaslr()) {
+ if (!IS_ENABLED(CONFIG_HIBERNATION) && !nokaslr() && !flat_va_mapping) {
/*
* Randomize the base of the UEFI runtime services region.
* Preserve the 2 MB alignment of the region by taking a
@@ -257,71 +320,30 @@ unsigned long efi_entry(void *handle, efi_system_table_t *sys_table_arg,
install_memreserve_table();
- new_fdt_addr = fdt_addr;
- status = allocate_new_fdt_and_exit_boot(handle,
- &new_fdt_addr, efi_get_max_fdt_addr(dram_base),
- initrd_addr, initrd_size, cmdline_ptr,
- fdt_addr, fdt_size);
+ status = allocate_new_fdt_and_exit_boot(handle, &fdt_addr,
+ efi_get_max_fdt_addr(dram_base),
+ initrd_addr, initrd_size,
+ cmdline_ptr, fdt_addr, fdt_size);
+ if (status != EFI_SUCCESS)
+ goto fail_free_initrd;
- /*
- * If all went well, we need to return the FDT address to the
- * calling function so it can be passed to kernel as part of
- * the kernel boot protocol.
- */
- if (status == EFI_SUCCESS)
- return new_fdt_addr;
+ efi_enter_kernel(image_addr, fdt_addr, fdt_totalsize((void *)fdt_addr));
+ /* not reached */
+fail_free_initrd:
pr_efi_err("Failed to update FDT and exit boot services\n");
efi_free(initrd_size, initrd_addr);
efi_free(fdt_size, fdt_addr);
fail_free_image:
- efi_free(image_size, *image_addr);
+ efi_free(image_size, image_addr);
efi_free(reserve_size, reserve_addr);
fail_free_cmdline:
free_screen_info(si);
efi_free(cmdline_size, (unsigned long)cmdline_ptr);
fail:
- return EFI_ERROR;
-}
-
-static int cmp_mem_desc(const void *l, const void *r)
-{
- const efi_memory_desc_t *left = l, *right = r;
-
- return (left->phys_addr > right->phys_addr) ? 1 : -1;
-}
-
-/*
- * Returns whether region @left ends exactly where region @right starts,
- * or false if either argument is NULL.
- */
-static bool regions_are_adjacent(efi_memory_desc_t *left,
- efi_memory_desc_t *right)
-{
- u64 left_end;
-
- if (left == NULL || right == NULL)
- return false;
-
- left_end = left->phys_addr + left->num_pages * EFI_PAGE_SIZE;
-
- return left_end == right->phys_addr;
-}
-
-/*
- * Returns whether region @left and region @right have compatible memory type
- * mapping attributes, and are both EFI_MEMORY_RUNTIME regions.
- */
-static bool regions_have_compatible_memory_type_attrs(efi_memory_desc_t *left,
- efi_memory_desc_t *right)
-{
- static const u64 mem_type_mask = EFI_MEMORY_WB | EFI_MEMORY_WT |
- EFI_MEMORY_WC | EFI_MEMORY_UC |
- EFI_MEMORY_RUNTIME;
-
- return ((left->attribute ^ right->attribute) & mem_type_mask) == 0;
+ return status;
}
/*
@@ -336,23 +358,10 @@ void efi_get_virtmap(efi_memory_desc_t *memory_map, unsigned long map_size,
int *count)
{
u64 efi_virt_base = virtmap_base;
- efi_memory_desc_t *in, *prev = NULL, *out = runtime_map;
+ efi_memory_desc_t *in, *out = runtime_map;
int l;
- /*
- * To work around potential issues with the Properties Table feature
- * introduced in UEFI 2.5, which may split PE/COFF executable images
- * in memory into several RuntimeServicesCode and RuntimeServicesData
- * regions, we need to preserve the relative offsets between adjacent
- * EFI_MEMORY_RUNTIME regions with the same memory type attributes.
- * The easiest way to find adjacent regions is to sort the memory map
- * before traversing it.
- */
- if (IS_ENABLED(CONFIG_ARM64))
- sort(memory_map, map_size / desc_size, desc_size, cmp_mem_desc,
- NULL);
-
- for (l = 0; l < map_size; l += desc_size, prev = in) {
+ for (l = 0; l < map_size; l += desc_size) {
u64 paddr, size;
in = (void *)memory_map + l;
@@ -362,8 +371,8 @@ void efi_get_virtmap(efi_memory_desc_t *memory_map, unsigned long map_size,
paddr = in->phys_addr;
size = in->num_pages * EFI_PAGE_SIZE;
+ in->virt_addr = in->phys_addr;
if (novamap()) {
- in->virt_addr = in->phys_addr;
continue;
}
@@ -372,9 +381,7 @@ void efi_get_virtmap(efi_memory_desc_t *memory_map, unsigned long map_size,
* a 4k page size kernel to kexec a 64k page size kernel and
* vice versa.
*/
- if ((IS_ENABLED(CONFIG_ARM64) &&
- !regions_are_adjacent(prev, in)) ||
- !regions_have_compatible_memory_type_attrs(prev, in)) {
+ if (!flat_va_mapping) {
paddr = round_down(in->phys_addr, SZ_64K);
size += in->phys_addr - paddr;
@@ -389,10 +396,10 @@ void efi_get_virtmap(efi_memory_desc_t *memory_map, unsigned long map_size,
efi_virt_base = round_up(efi_virt_base, SZ_2M);
else
efi_virt_base = round_up(efi_virt_base, SZ_64K);
- }
- in->virt_addr = efi_virt_base + in->phys_addr - paddr;
- efi_virt_base += size;
+ in->virt_addr += efi_virt_base - paddr;
+ efi_virt_base += size;
+ }
memcpy(out, in, desc_size);
out = (void *)out + desc_size;