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authorLinus Torvalds <torvalds@linux-foundation.org>2020-01-28 20:03:40 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2020-01-28 20:03:40 +0300
commit634cd4b6afe15dca8df02bcba242b9b0c5e9b5a5 (patch)
tree4865e4ec64a0575614a81d88f523269c04e17f09 /arch/x86/boot/compressed/efi_stub_32.S
parentd99391ec2b42d827d92003dcdcb96fadac9d862b (diff)
parentac6119e7f25b842fc061e8aec88c4f32d3bc28ef (diff)
downloadlinux-634cd4b6afe15dca8df02bcba242b9b0c5e9b5a5.tar.xz
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: - Cleanup of the GOP [graphics output] handling code in the EFI stub - Complete refactoring of the mixed mode handling in the x86 EFI stub - Overhaul of the x86 EFI boot/runtime code - Increase robustness for mixed mode code - Add the ability to disable DMA at the root port level in the EFI stub - Get rid of RWX mappings in the EFI memory map and page tables, where possible - Move the support code for the old EFI memory mapping style into its only user, the SGI UV1+ support code. - plus misc fixes, updates, smaller cleanups. ... and due to interactions with the RWX changes, another round of PAT cleanups make a guest appearance via the EFI tree - with no side effects intended" * 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (75 commits) efi/x86: Disable instrumentation in the EFI runtime handling code efi/libstub/x86: Fix EFI server boot failure efi/x86: Disallow efi=old_map in mixed mode x86/boot/compressed: Relax sed symbol type regex for LLVM ld.lld efi/x86: avoid KASAN false positives when accessing the 1: 1 mapping efi: Fix handling of multiple efi_fake_mem= entries efi: Fix efi_memmap_alloc() leaks efi: Add tracking for dynamically allocated memmaps efi: Add a flags parameter to efi_memory_map efi: Fix comment for efi_mem_type() wrt absent physical addresses efi/arm: Defer probe of PCIe backed efifb on DT systems efi/x86: Limit EFI old memory map to SGI UV machines efi/x86: Avoid RWX mappings for all of DRAM efi/x86: Don't map the entire kernel text RW for mixed mode x86/mm: Fix NX bit clearing issue in kernel_map_pages_in_pgd efi/libstub/x86: Fix unused-variable warning efi/libstub/x86: Use mandatory 16-byte stack alignment in mixed mode efi/libstub/x86: Use const attribute for efi_is_64bit() efi: Allow disabling PCI busmastering on bridges during boot efi/x86: Allow translating 64-bit arguments for mixed mode calls ...
Diffstat (limited to 'arch/x86/boot/compressed/efi_stub_32.S')
-rw-r--r--arch/x86/boot/compressed/efi_stub_32.S87
1 files changed, 0 insertions, 87 deletions
diff --git a/arch/x86/boot/compressed/efi_stub_32.S b/arch/x86/boot/compressed/efi_stub_32.S
deleted file mode 100644
index ed6c351d34ed..000000000000
--- a/arch/x86/boot/compressed/efi_stub_32.S
+++ /dev/null
@@ -1,87 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- * EFI call stub for IA32.
- *
- * This stub allows us to make EFI calls in physical mode with interrupts
- * turned off. Note that this implementation is different from the one in
- * arch/x86/platform/efi/efi_stub_32.S because we're _already_ in physical
- * mode at this point.
- */
-
-#include <linux/linkage.h>
-#include <asm/page_types.h>
-
-/*
- * efi_call_phys(void *, ...) is a function with variable parameters.
- * All the callers of this function assure that all the parameters are 4-bytes.
- */
-
-/*
- * In gcc calling convention, EBX, ESP, EBP, ESI and EDI are all callee save.
- * So we'd better save all of them at the beginning of this function and restore
- * at the end no matter how many we use, because we can not assure EFI runtime
- * service functions will comply with gcc calling convention, too.
- */
-
-.text
-SYM_FUNC_START(efi_call_phys)
- /*
- * 0. The function can only be called in Linux kernel. So CS has been
- * set to 0x0010, DS and SS have been set to 0x0018. In EFI, I found
- * the values of these registers are the same. And, the corresponding
- * GDT entries are identical. So I will do nothing about segment reg
- * and GDT, but change GDT base register in prelog and epilog.
- */
-
- /*
- * 1. Because we haven't been relocated by this point we need to
- * use relative addressing.
- */
- call 1f
-1: popl %edx
- subl $1b, %edx
-
- /*
- * 2. Now on the top of stack is the return
- * address in the caller of efi_call_phys(), then parameter 1,
- * parameter 2, ..., param n. To make things easy, we save the return
- * address of efi_call_phys in a global variable.
- */
- popl %ecx
- movl %ecx, saved_return_addr(%edx)
- /* get the function pointer into ECX*/
- popl %ecx
- movl %ecx, efi_rt_function_ptr(%edx)
-
- /*
- * 3. Call the physical function.
- */
- call *%ecx
-
- /*
- * 4. Balance the stack. And because EAX contain the return value,
- * we'd better not clobber it. We need to calculate our address
- * again because %ecx and %edx are not preserved across EFI function
- * calls.
- */
- call 1f
-1: popl %edx
- subl $1b, %edx
-
- movl efi_rt_function_ptr(%edx), %ecx
- pushl %ecx
-
- /*
- * 10. Push the saved return address onto the stack and return.
- */
- movl saved_return_addr(%edx), %ecx
- pushl %ecx
- ret
-SYM_FUNC_END(efi_call_phys)
-.previous
-
-.data
-saved_return_addr:
- .long 0
-efi_rt_function_ptr:
- .long 0