riscv: Prepare EFI header for relocatable kernels

ld does not handle relocations correctly as explained here [1],
a fix for that was proposed by Nelson there but we have to support older
toolchains and then provide this fix.

Note that llvm does not need this fix and is then excluded.

[1] https://sourceware.org/pipermail/binutils/2023-March/126690.html

Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20230329045329.64565-2-alexghiti@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

diff --git a/arch/riscv/include/asm/set_memory.h b/arch/riscv/include/asm/set_memory.h
index a2c14d4..ec11001 100644 (file)
--- a/arch/riscv/include/asm/set_memory.h
+++ b/arch/riscv/include/asm/set_memory.h
@@ -56,4 +56,7 @@ bool kernel_page_present(struct page *page);
 #define SECTION_ALIGN L1_CACHE_BYTES
 #endif /* CONFIG_STRICT_KERNEL_RWX */
 
+#define PECOFF_SECTION_ALIGNMENT        0x1000
+#define PECOFF_FILE_ALIGNMENT           0x200
+
 #endif /* _ASM_RISCV_SET_MEMORY_H */

diff --git a/arch/riscv/kernel/efi-header.S b/arch/riscv/kernel/efi-header.S
index 8e733aa..515b2df 100644 (file)
--- a/arch/riscv/kernel/efi-header.S
+++ b/arch/riscv/kernel/efi-header.S
@@ -6,6 +6,7 @@
 
 #include <linux/pe.h>
 #include <linux/sizes.h>
+#include <asm/set_memory.h>
 
        .macro  __EFI_PE_HEADER
        .long   PE_MAGIC
@@ -33,7 +34,11 @@ optional_header:
        .byte   0x02                                    // MajorLinkerVersion
        .byte   0x14                                    // MinorLinkerVersion
        .long   __pecoff_text_end - efi_header_end      // SizeOfCode
-       .long   __pecoff_data_virt_size                 // SizeOfInitializedData
+#ifdef __clang__
+       .long   __pecoff_data_virt_size                 // SizeOfInitializedData
+#else
+       .long   __pecoff_data_virt_end - __pecoff_text_end      // SizeOfInitializedData
+#endif
        .long   0                                       // SizeOfUninitializedData
        .long   __efistub_efi_pe_entry - _start         // AddressOfEntryPoint
        .long   efi_header_end - _start                 // BaseOfCode
@@ -91,9 +96,17 @@ section_table:
                IMAGE_SCN_MEM_EXECUTE                   // Characteristics
 
        .ascii  ".data\0\0\0"
-       .long   __pecoff_data_virt_size                 // VirtualSize
+#ifdef __clang__
+       .long   __pecoff_data_virt_size                 // VirtualSize
+#else
+       .long   __pecoff_data_virt_end - __pecoff_text_end      // VirtualSize
+#endif
        .long   __pecoff_text_end - _start              // VirtualAddress
-       .long   __pecoff_data_raw_size                  // SizeOfRawData
+#ifdef __clang__
+       .long   __pecoff_data_raw_size                  // SizeOfRawData
+#else
+       .long   __pecoff_data_raw_end - __pecoff_text_end       // SizeOfRawData
+#endif
        .long   __pecoff_text_end - _start              // PointerToRawData
 
        .long   0                                       // PointerToRelocations

diff --git a/arch/riscv/kernel/vmlinux.lds.S b/arch/riscv/kernel/vmlinux.lds.S
index 53a8ad6..1c38294 100644 (file)
--- a/arch/riscv/kernel/vmlinux.lds.S
+++ b/arch/riscv/kernel/vmlinux.lds.S
@@ -27,9 +27,6 @@ ENTRY(_start)
 
 jiffies = jiffies_64;
 
-PECOFF_SECTION_ALIGNMENT = 0x1000;
-PECOFF_FILE_ALIGNMENT = 0x200;
-
 SECTIONS
 {
        /* Beginning of code and text segment */
@@ -132,6 +129,7 @@ SECTIONS
 #ifdef CONFIG_EFI
        .pecoff_edata_padding : { BYTE(0); . = ALIGN(PECOFF_FILE_ALIGNMENT); }
        __pecoff_data_raw_size = ABSOLUTE(. - __pecoff_text_end);
+       __pecoff_data_raw_end = ABSOLUTE(.);
 #endif
 
        /* End of data section */
@@ -142,6 +140,7 @@ SECTIONS
 #ifdef CONFIG_EFI
        . = ALIGN(PECOFF_SECTION_ALIGNMENT);
        __pecoff_data_virt_size = ABSOLUTE(. - __pecoff_text_end);
+       __pecoff_data_virt_end = ABSOLUTE(.);
 #endif
        _end = .;