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-rw-r--r--packages/glibc/2.26/0001-aarch64-rewrite-elf_machine_load_address.patch75
1 files changed, 75 insertions, 0 deletions
diff --git a/packages/glibc/2.26/0001-aarch64-rewrite-elf_machine_load_address.patch b/packages/glibc/2.26/0001-aarch64-rewrite-elf_machine_load_address.patch
new file mode 100644
index 0000000..14c0780
--- /dev/null
+++ b/packages/glibc/2.26/0001-aarch64-rewrite-elf_machine_load_address.patch
@@ -0,0 +1,75 @@
+commit a68ba2f3cd3cbe32c1f31e13c20ed13487727b32
+Author: Szabolcs Nagy <szabolcs.nagy@arm.com>
+Date: Wed Oct 18 17:26:23 2017 +0100
+
+ [AARCH64] Rewrite elf_machine_load_address using _DYNAMIC symbol
+
+ This patch rewrites aarch64 elf_machine_load_address to use special _DYNAMIC
+ symbol instead of _dl_start.
+
+ The static address of _DYNAMIC symbol is stored in the first GOT entry.
+ Here is the change which makes this solution work (part of binutils 2.24):
+ https://sourceware.org/ml/binutils/2013-06/msg00248.html
+
+ i386, x86_64 targets use the same method to do this as well.
+
+ The original implementation relies on a trick that R_AARCH64_ABS32 relocation
+ being resolved at link time and the static address fits in the 32bits.
+ However, in LP64, normally, the address is defined to be 64 bit.
+
+ Here is the C version one which should be portable in all cases.
+
+ * sysdeps/aarch64/dl-machine.h (elf_machine_load_address): Use
+ _DYNAMIC symbol to calculate load address.
+
+---
+ sysdeps/aarch64/dl-machine.h | 37 ++++---------------------------------
+ 1 file changed, 4 insertions(+), 33 deletions(-)
+
+--- a/sysdeps/aarch64/dl-machine.h
++++ b/sysdeps/aarch64/dl-machine.h
+@@ -51,40 +51,11 @@
+ /* To figure out the load address we use the definition that for any symbol:
+ dynamic_addr(symbol) = static_addr(symbol) + load_addr
+
+- The choice of symbol is arbitrary. The static address we obtain
+- by constructing a non GOT reference to the symbol, the dynamic
+- address of the symbol we compute using adrp/add to compute the
+- symbol's address relative to the PC.
+- This depends on 32/16bit relocations being resolved at link time
+- and that the static address fits in the 32/16 bits. */
++ _DYNAMIC sysmbol is used here as its link-time address stored in
++ the special unrelocated first GOT entry. */
+
+- ElfW(Addr) static_addr;
+- ElfW(Addr) dynamic_addr;
+-
+- asm (" \n"
+-" adrp %1, _dl_start; \n"
+-#ifdef __LP64__
+-" add %1, %1, #:lo12:_dl_start \n"
+-#else
+-" add %w1, %w1, #:lo12:_dl_start \n"
+-#endif
+-" ldr %w0, 1f \n"
+-" b 2f \n"
+-"1: \n"
+-#ifdef __LP64__
+-" .word _dl_start \n"
+-#else
+-# ifdef __AARCH64EB__
+-" .short 0 \n"
+-# endif
+-" .short _dl_start \n"
+-# ifndef __AARCH64EB__
+-" .short 0 \n"
+-# endif
+-#endif
+-"2: \n"
+- : "=r" (static_addr), "=r" (dynamic_addr));
+- return dynamic_addr - static_addr;
++ extern ElfW(Dyn) _DYNAMIC[] attribute_hidden;
++ return (ElfW(Addr)) &_DYNAMIC - elf_machine_dynamic ();
+ }
+
+ /* Set up the loaded object described by L so its unrelocated PLT