2016-08-04 Thomas Preud'homme <thomas.preudhomme@arm.com>

bfd/
	* elf32-arm.c (CMSE_PREFIX): Define macro.
	(elf32_arm_stub_cmse_branch_thumb_only): Define stub sequence.
	(cmse_branch_thumb_only): Declare stub.
	(struct elf32_arm_link_hash_table): Define cmse_stub_sec field.
	(elf32_arm_get_plt_info): Add globals parameter.  Use it to return
	FALSE if there is no PLT.
	(arm_type_of_stub): Adapt to new elf32_arm_get_plt_info signature.
	(elf32_arm_final_link_relocate): Likewise.
	(elf32_arm_gc_sweep_hook): Likewise.
	(elf32_arm_gc_mark_extra_sections): Mark sections holding ARMv8-M
	secure entry functions.
	(arm_stub_is_thumb): Add case for arm_stub_cmse_branch_thumb_only.
	(arm_dedicated_stub_output_section_required): Change to a switch case
	and add a case for arm_stub_cmse_branch_thumb_only.
	(arm_dedicated_stub_output_section_required_alignment): Likewise.
	(arm_stub_dedicated_output_section_name): Likewise.
	(arm_stub_dedicated_input_section_ptr): Likewise and remove
	ATTRIBUTE_UNUSED for htab parameter.
	(arm_stub_required_alignment): Likewise.
	(arm_stub_sym_claimed): Likewise.
	(arm_dedicated_stub_section_padding): Likewise.
	(cmse_scan): New function.
	(elf32_arm_size_stubs): Call cmse_scan for ARM M profile targets.
	Set stub_changed to TRUE if such veneers were created.
	(elf32_arm_swap_symbol_in): Add detection code for CMSE special
	symbols.

include/
	* arm.h (ARM_GET_SYM_CMSE_SPCL): Define macro.
	(ARM_SET_SYM_CMSE_SPCL): Likewise.

ld/
	* ld.texinfo (Placement of SG veneers): New concept entry.
	* testsuite/ld-arm/arm-elf.exp
	(Secure gateway veneers: no .gnu.sgstubs section): New test.
	(Secure gateway veneers: wrong entry functions): Likewise.
	(Secure gateway veneers (ARMv8-M Baseline)): Likewise.
	(Secure gateway veneers (ARMv8-M Mainline)): Likewise.
	* testsuite/ld-arm/cmse-veneers.s: New file.
	* testsuite/ld-arm/cmse-veneers.d: Likewise.
	* testsuite/ld-arm/cmse-veneers.rd: Likewise.
	* testsuite/ld-arm/cmse-veneers.sd: Likewise.
	* testsuite/ld-arm/cmse-veneers-no-gnu_sgstubs.out: Likewise.
	* testsuite/ld-arm/cmse-veneers-wrong-entryfct.out: Likewise.
This commit is contained in:
Thomas Preud'homme 2016-08-04 15:36:52 +01:00
parent 024425668d
commit 4ba2ef8fbe
13 changed files with 608 additions and 20 deletions

View File

@ -1,3 +1,32 @@
2016-08-04 Thomas Preud'homme <thomas.preudhomme@arm.com>
* elf32-arm.c (CMSE_PREFIX): Define macro.
(elf32_arm_stub_cmse_branch_thumb_only): Define stub sequence.
(cmse_branch_thumb_only): Declare stub.
(struct elf32_arm_link_hash_table): Define cmse_stub_sec field.
(elf32_arm_get_plt_info): Add globals parameter. Use it to return
FALSE if there is no PLT.
(arm_type_of_stub): Adapt to new elf32_arm_get_plt_info signature.
(elf32_arm_final_link_relocate): Likewise.
(elf32_arm_gc_sweep_hook): Likewise.
(elf32_arm_gc_mark_extra_sections): Mark sections holding ARMv8-M
secure entry functions.
(arm_stub_is_thumb): Add case for arm_stub_cmse_branch_thumb_only.
(arm_dedicated_stub_output_section_required): Change to a switch case
and add a case for arm_stub_cmse_branch_thumb_only.
(arm_dedicated_stub_output_section_required_alignment): Likewise.
(arm_stub_dedicated_output_section_name): Likewise.
(arm_stub_dedicated_input_section_ptr): Likewise and remove
ATTRIBUTE_UNUSED for htab parameter.
(arm_stub_required_alignment): Likewise.
(arm_stub_sym_claimed): Likewise.
(arm_dedicated_stub_section_padding): Likewise.
(cmse_scan): New function.
(elf32_arm_size_stubs): Call cmse_scan for ARM M profile targets.
Set stub_changed to TRUE if such veneers were created.
(elf32_arm_swap_symbol_in): Add detection code for CMSE special
symbols.
2016-08-02 Alan Modra <amodra@gmail.com>
PR ld/20428

View File

@ -2138,6 +2138,8 @@ typedef unsigned short int insn16;
#define STUB_ENTRY_NAME "__%s_veneer"
#define CMSE_PREFIX "__acle_se_"
/* The name of the dynamic interpreter. This is put in the .interp
section. */
#define ELF_DYNAMIC_INTERPRETER "/usr/lib/ld.so.1"
@ -2561,6 +2563,13 @@ static const insn_sequence elf32_arm_stub_long_branch_arm_nacl_pic[] =
DATA_WORD (0, R_ARM_NONE, 0), /* .word 0 */
};
/* Stub used for transition to secure state (aka SG veneer). */
static const insn_sequence elf32_arm_stub_cmse_branch_thumb_only[] =
{
THUMB32_INSN (0xe97fe97f), /* sg. */
THUMB32_B_INSN (0xf000b800, -4), /* b.w original_branch_dest. */
};
/* Cortex-A8 erratum-workaround stubs. */
@ -2640,6 +2649,7 @@ static const insn_sequence elf32_arm_stub_a8_veneer_blx[] =
DEF_STUB(long_branch_v4t_thumb_tls_pic) \
DEF_STUB(long_branch_arm_nacl) \
DEF_STUB(long_branch_arm_nacl_pic) \
DEF_STUB(cmse_branch_thumb_only) \
DEF_STUB(a8_veneer_b_cond) \
DEF_STUB(a8_veneer_b) \
DEF_STUB(a8_veneer_bl) \
@ -3192,6 +3202,9 @@ struct elf32_arm_link_hash_table
information on stub grouping. */
struct map_stub *stub_group;
/* Input stub section holding secure gateway veneers. */
asection *cmse_stub_sec;
/* Number of elements in stub_group. */
unsigned int top_id;
@ -3340,12 +3353,16 @@ elf32_arm_create_local_iplt (bfd *abfd, unsigned long r_symndx)
union and *ARM_PLT at the ARM-specific information. */
static bfd_boolean
elf32_arm_get_plt_info (bfd *abfd, struct elf32_arm_link_hash_entry *h,
elf32_arm_get_plt_info (bfd *abfd, struct elf32_arm_link_hash_table *globals,
struct elf32_arm_link_hash_entry *h,
unsigned long r_symndx, union gotplt_union **root_plt,
struct arm_plt_info **arm_plt)
{
struct arm_local_iplt_info *local_iplt;
if (globals->root.splt == NULL && globals->root.iplt == NULL)
return FALSE;
if (h != NULL)
{
*root_plt = &h->root.plt;
@ -3826,6 +3843,7 @@ arm_stub_is_thumb (enum elf32_arm_stub_type stub_type)
case arm_stub_long_branch_v4t_thumb_arm_pic:
case arm_stub_long_branch_v4t_thumb_tls_pic:
case arm_stub_long_branch_thumb_only_pic:
case arm_stub_cmse_branch_thumb_only:
return TRUE;
case arm_stub_none:
BFD_FAIL ();
@ -3897,8 +3915,9 @@ arm_type_of_stub (struct bfd_link_info *info,
the address of the appropriate trampoline. */
if (r_type != R_ARM_TLS_CALL
&& r_type != R_ARM_THM_TLS_CALL
&& elf32_arm_get_plt_info (input_bfd, hash, ELF32_R_SYM (rel->r_info),
&root_plt, &arm_plt)
&& elf32_arm_get_plt_info (input_bfd, globals, hash,
ELF32_R_SYM (rel->r_info), &root_plt,
&arm_plt)
&& root_plt->offset != (bfd_vma) -1)
{
asection *splt;
@ -4250,7 +4269,16 @@ arm_dedicated_stub_output_section_required (enum elf32_arm_stub_type stub_type)
if (stub_type >= max_stub_type)
abort (); /* Should be unreachable. */
return FALSE;
switch (stub_type)
{
case arm_stub_cmse_branch_thumb_only:
return TRUE;
default:
return FALSE;
}
abort (); /* Should be unreachable. */
}
/* Required alignment (as a power of 2) for the dedicated section holding
@ -4264,8 +4292,19 @@ arm_dedicated_stub_output_section_required_alignment
if (stub_type >= max_stub_type)
abort (); /* Should be unreachable. */
BFD_ASSERT (!arm_dedicated_stub_output_section_required (stub_type));
return 0;
switch (stub_type)
{
/* Vectors of Secure Gateway veneers must be aligned on 32byte
boundary. */
case arm_stub_cmse_branch_thumb_only:
return 5;
default:
BFD_ASSERT (!arm_dedicated_stub_output_section_required (stub_type));
return 0;
}
abort (); /* Should be unreachable. */
}
/* Name of the dedicated output section to put veneers of type STUB_TYPE, or
@ -4277,8 +4316,17 @@ arm_dedicated_stub_output_section_name (enum elf32_arm_stub_type stub_type)
if (stub_type >= max_stub_type)
abort (); /* Should be unreachable. */
BFD_ASSERT (!arm_dedicated_stub_output_section_required (stub_type));
return NULL;
switch (stub_type)
{
case arm_stub_cmse_branch_thumb_only:
return ".gnu.sgstubs";
default:
BFD_ASSERT (!arm_dedicated_stub_output_section_required (stub_type));
return NULL;
}
abort (); /* Should be unreachable. */
}
/* If veneers of type STUB_TYPE should go in a dedicated output section,
@ -4286,15 +4334,23 @@ arm_dedicated_stub_output_section_name (enum elf32_arm_stub_type stub_type)
corresponding input section. Otherwise, returns NULL. */
static asection **
arm_dedicated_stub_input_section_ptr
(struct elf32_arm_link_hash_table *htab ATTRIBUTE_UNUSED,
enum elf32_arm_stub_type stub_type)
arm_dedicated_stub_input_section_ptr (struct elf32_arm_link_hash_table *htab,
enum elf32_arm_stub_type stub_type)
{
if (stub_type >= max_stub_type)
abort (); /* Should be unreachable. */
BFD_ASSERT (!arm_dedicated_stub_output_section_required (stub_type));
return NULL;
switch (stub_type)
{
case arm_stub_cmse_branch_thumb_only:
return &htab->cmse_stub_sec;
default:
BFD_ASSERT (!arm_dedicated_stub_output_section_required (stub_type));
return NULL;
}
abort (); /* Should be unreachable. */
}
/* Find or create a stub section to contain a stub of type STUB_TYPE. SECTION
@ -4518,6 +4574,7 @@ arm_stub_required_alignment (enum elf32_arm_stub_type stub_type)
case arm_stub_long_branch_thumb_only_pic:
case arm_stub_long_branch_any_tls_pic:
case arm_stub_long_branch_v4t_thumb_tls_pic:
case arm_stub_cmse_branch_thumb_only:
case arm_stub_a8_veneer_blx:
return 4;
@ -4539,7 +4596,16 @@ arm_stub_sym_claimed (enum elf32_arm_stub_type stub_type)
if (stub_type >= max_stub_type)
abort (); /* Should be unreachable. */
return FALSE;
switch (stub_type)
{
case arm_stub_cmse_branch_thumb_only:
return TRUE;
default:
return FALSE;
}
abort (); /* Should be unreachable. */
}
/* Returns the padding needed for the dedicated section used stubs of type
@ -4551,7 +4617,16 @@ arm_dedicated_stub_section_padding (enum elf32_arm_stub_type stub_type)
if (stub_type >= max_stub_type)
abort (); /* Should be unreachable. */
return 0;
switch (stub_type)
{
case arm_stub_cmse_branch_thumb_only:
return 32;
default:
return 0;
}
abort (); /* Should be unreachable. */
}
static bfd_boolean
@ -5442,6 +5517,204 @@ elf32_arm_create_stub (struct elf32_arm_link_hash_table *htab,
return TRUE;
}
/* Scan symbols in INPUT_BFD to identify secure entry functions needing a
gateway veneer to transition from non secure to secure state and create them
accordingly.
"ARMv8-M Security Extensions: Requirements on Development Tools" document
defines the conditions that govern Secure Gateway veneer creation for a
given symbol <SYM> as follows:
- it has function type
- it has non local binding
- a symbol named __acle_se_<SYM> (called special symbol) exists with the
same type, binding and value as <SYM> (called normal symbol).
An entry function can handle secure state transition itself in which case
its special symbol would have a different value from the normal symbol.
OUT_ATTR gives the output attributes, SYM_HASHES the symbol index to hash
entry mapping while HTAB gives the name to hash entry mapping.
If any secure gateway veneer is created, *STUB_CHANGED is set to TRUE. The
return value gives whether a stub failed to be allocated. */
static bfd_boolean
cmse_scan (bfd *input_bfd, struct elf32_arm_link_hash_table *htab,
obj_attribute *out_attr, struct elf_link_hash_entry **sym_hashes,
bfd_boolean *stub_changed)
{
const struct elf_backend_data *bed;
Elf_Internal_Shdr *symtab_hdr;
unsigned i, j, sym_count, ext_start;
Elf_Internal_Sym *cmse_sym, *local_syms;
struct elf32_arm_link_hash_entry *hash, *cmse_hash = NULL;
enum arm_st_branch_type branch_type;
char *sym_name, *lsym_name;
bfd_vma sym_value;
asection *section;
bfd_boolean is_v8m, new_stub, created_stub, cmse_invalid, ret = TRUE;
bed = get_elf_backend_data (input_bfd);
symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
sym_count = symtab_hdr->sh_size / bed->s->sizeof_sym;
ext_start = symtab_hdr->sh_info;
is_v8m = (out_attr[Tag_CPU_arch].i >= TAG_CPU_ARCH_V8M_BASE
&& out_attr[Tag_CPU_arch_profile].i == 'M');
local_syms = (Elf_Internal_Sym *) symtab_hdr->contents;
if (local_syms == NULL)
local_syms = bfd_elf_get_elf_syms (input_bfd, symtab_hdr,
symtab_hdr->sh_info, 0, NULL, NULL,
NULL);
if (symtab_hdr->sh_info && local_syms == NULL)
return FALSE;
/* Scan symbols. */
for (i = 0; i < sym_count; i++)
{
cmse_invalid = FALSE;
if (i < ext_start)
{
cmse_sym = &local_syms[i];
/* Not a special symbol. */
if (!ARM_GET_SYM_CMSE_SPCL (cmse_sym->st_target_internal))
continue;
sym_name = bfd_elf_string_from_elf_section (input_bfd,
symtab_hdr->sh_link,
cmse_sym->st_name);
/* Special symbol with local binding. */
cmse_invalid = TRUE;
}
else
{
cmse_hash = elf32_arm_hash_entry (sym_hashes[i - ext_start]);
sym_name = (char *) cmse_hash->root.root.root.string;
/* Not a special symbol. */
if (!ARM_GET_SYM_CMSE_SPCL (cmse_hash->root.target_internal))
continue;
/* Special symbol has incorrect binding or type. */
if ((cmse_hash->root.root.type != bfd_link_hash_defined
&& cmse_hash->root.root.type != bfd_link_hash_defweak)
|| cmse_hash->root.type != STT_FUNC)
cmse_invalid = TRUE;
}
if (!is_v8m)
{
(*_bfd_error_handler) (_("%B: Special symbol `%s' only allowed for "
"ARMv8-M architecture or later."),
input_bfd, sym_name);
is_v8m = TRUE; /* Avoid multiple warning. */
ret = FALSE;
}
if (cmse_invalid)
{
(*_bfd_error_handler) (_("%B: invalid special symbol `%s'."),
input_bfd, sym_name);
(*_bfd_error_handler) (_("It must be a global or weak function "
"symbol."));
ret = FALSE;
if (i < ext_start)
continue;
}
sym_name += strlen (CMSE_PREFIX);
hash = (struct elf32_arm_link_hash_entry *)
elf_link_hash_lookup (&(htab)->root, sym_name, FALSE, FALSE, TRUE);
/* No associated normal symbol or it is neither global nor weak. */
if (!hash
|| (hash->root.root.type != bfd_link_hash_defined
&& hash->root.root.type != bfd_link_hash_defweak)
|| hash->root.type != STT_FUNC)
{
/* Initialize here to avoid warning about use of possibly
uninitialized variable. */
j = 0;
if (!hash)
{
/* Searching for a normal symbol with local binding. */
for (; j < ext_start; j++)
{
lsym_name =
bfd_elf_string_from_elf_section (input_bfd,
symtab_hdr->sh_link,
local_syms[j].st_name);
if (!strcmp (sym_name, lsym_name))
break;
}
}
if (hash || j < ext_start)
{
(*_bfd_error_handler)
(_("%B: invalid standard symbol `%s'."), input_bfd, sym_name);
(*_bfd_error_handler)
(_("It must be a global or weak function symbol."));
}
else
(*_bfd_error_handler)
(_("%B: absent standard symbol `%s'."), input_bfd, sym_name);
ret = FALSE;
if (!hash)
continue;
}
sym_value = hash->root.root.u.def.value;
section = hash->root.root.u.def.section;
if (cmse_hash->root.root.u.def.section != section)
{
(*_bfd_error_handler)
(_("%B: `%s' and its special symbol are in different sections."),
input_bfd, sym_name);
ret = FALSE;
}
if (cmse_hash->root.root.u.def.value != sym_value)
continue; /* Ignore: could be an entry function starting with SG. */
/* If this section is a link-once section that will be discarded, then
don't create any stubs. */
if (section->output_section == NULL)
{
(*_bfd_error_handler)
(_("%B: entry function `%s' not output."), input_bfd, sym_name);
continue;
}
if (hash->root.size == 0)
{
(*_bfd_error_handler)
(_("%B: entry function `%s' is empty."), input_bfd, sym_name);
ret = FALSE;
}
if (!ret)
continue;
branch_type = ARM_GET_SYM_BRANCH_TYPE (hash->root.target_internal);
created_stub
= elf32_arm_create_stub (htab, arm_stub_cmse_branch_thumb_only,
NULL, NULL, section, hash, sym_name,
sym_value, branch_type, &new_stub);
if (!created_stub)
ret = FALSE;
else
{
BFD_ASSERT (new_stub);
*stub_changed = TRUE;
}
}
if (!symtab_hdr->contents)
free (local_syms);
return ret;
}
/* Determine and set the size of the stub section for a final link.
The basic idea here is to examine all the relocations looking for
@ -5458,8 +5731,9 @@ elf32_arm_size_stubs (bfd *output_bfd,
unsigned int),
void (*layout_sections_again) (void))
{
obj_attribute *out_attr;
bfd_size_type stub_group_size;
bfd_boolean stubs_always_after_branch;
bfd_boolean m_profile, stubs_always_after_branch, first_veneer_scan = TRUE;
struct elf32_arm_link_hash_table *htab = elf32_arm_hash_table (info);
struct a8_erratum_fix *a8_fixes = NULL;
unsigned int num_a8_fixes = 0, a8_fix_table_size = 10;
@ -5488,6 +5762,8 @@ elf32_arm_size_stubs (bfd *output_bfd,
htab->layout_sections_again = layout_sections_again;
stubs_always_after_branch = group_size < 0;
out_attr = elf_known_obj_attributes_proc (output_bfd);
m_profile = out_attr[Tag_CPU_arch_profile].i == 'M';
/* The Cortex-A8 erratum fix depends on stubs not being in the same 4K page
as the first half of a 32-bit branch straddling two 4K pages. This is a
crude way of enforcing that. */
@ -5553,6 +5829,18 @@ elf32_arm_size_stubs (bfd *output_bfd,
if (symtab_hdr->sh_info == 0)
continue;
/* Limit scan of symbols to object file whose profile is
Microcontroller to not hinder performance in the general case. */
if (m_profile && first_veneer_scan)
{
struct elf_link_hash_entry **sym_hashes;
sym_hashes = elf_sym_hashes (input_bfd);
if (!cmse_scan (input_bfd, htab, out_attr, sym_hashes,
&stub_changed))
goto error_ret_free_local;
}
/* Walk over each section attached to the input bfd. */
for (section = input_bfd->sections;
section != NULL;
@ -5939,6 +6227,7 @@ elf32_arm_size_stubs (bfd *output_bfd,
/* Ask the linker to do its stuff. */
(*htab->layout_sections_again) ();
first_veneer_scan = FALSE;
}
/* Add stubs for Cortex-A8 erratum fixes now. */
@ -9280,7 +9569,8 @@ elf32_arm_final_link_relocate (reloc_howto_type * howto,
/* Find out whether the symbol has a PLT. Set ST_VALUE, BRANCH_TYPE and
VALUE appropriately for relocations that we resolve at link time. */
has_iplt_entry = FALSE;
if (elf32_arm_get_plt_info (input_bfd, eh, r_symndx, &root_plt, &arm_plt)
if (elf32_arm_get_plt_info (input_bfd, globals, eh, r_symndx, &root_plt,
&arm_plt)
&& root_plt->offset != (bfd_vma) -1)
{
plt_offset = root_plt->offset;
@ -13693,7 +13983,8 @@ elf32_arm_gc_sweep_hook (bfd * abfd,
}
if (may_need_local_target_p
&& elf32_arm_get_plt_info (abfd, eh, r_symndx, &root_plt, &arm_plt))
&& elf32_arm_get_plt_info (abfd, globals, eh, r_symndx, &root_plt,
&arm_plt))
{
/* If PLT refcount book-keeping is wrong and too low, we'll
see a zero value (going to -1) for the root PLT reference
@ -14161,7 +14452,11 @@ elf32_arm_check_relocs (bfd *abfd, struct bfd_link_info *info,
}
/* Unwinding tables are not referenced directly. This pass marks them as
required if the corresponding code section is marked. */
required if the corresponding code section is marked. Similarly, ARMv8-M
secure entry functions can only be referenced by SG veneers which are
created after the GC process. They need to be marked in case they reside in
their own section (as would be the case if code was compiled with
-ffunction-sections). */
static bfd_boolean
elf32_arm_gc_mark_extra_sections (struct bfd_link_info *info,
@ -14169,10 +14464,21 @@ elf32_arm_gc_mark_extra_sections (struct bfd_link_info *info,
{
bfd *sub;
Elf_Internal_Shdr **elf_shdrp;
bfd_boolean again;
asection *cmse_sec;
obj_attribute *out_attr;
Elf_Internal_Shdr *symtab_hdr;
unsigned i, sym_count, ext_start;
const struct elf_backend_data *bed;
struct elf_link_hash_entry **sym_hashes;
struct elf32_arm_link_hash_entry *cmse_hash;
bfd_boolean again, is_v8m, first_bfd_browse = TRUE;
_bfd_elf_gc_mark_extra_sections (info, gc_mark_hook);
out_attr = elf_known_obj_attributes_proc (info->output_bfd);
is_v8m = out_attr[Tag_CPU_arch].i >= TAG_CPU_ARCH_V8M_BASE
&& out_attr[Tag_CPU_arch_profile].i == 'M';
/* Marking EH data may cause additional code sections to be marked,
requiring multiple passes. */
again = TRUE;
@ -14203,7 +14509,34 @@ elf32_arm_gc_mark_extra_sections (struct bfd_link_info *info,
return FALSE;
}
}
/* Mark section holding ARMv8-M secure entry functions. We mark all
of them so no need for a second browsing. */
if (is_v8m && first_bfd_browse)
{
sym_hashes = elf_sym_hashes (sub);
bed = get_elf_backend_data (sub);
symtab_hdr = &elf_tdata (sub)->symtab_hdr;
sym_count = symtab_hdr->sh_size / bed->s->sizeof_sym;
ext_start = symtab_hdr->sh_info;
/* Scan symbols. */
for (i = ext_start; i < sym_count; i++)
{
cmse_hash = elf32_arm_hash_entry (sym_hashes[i - ext_start]);
/* Assume it is a special symbol. If not, cmse_scan will
warn about it and user can do something about it. */
if (ARM_GET_SYM_CMSE_SPCL (cmse_hash->root.target_internal))
{
cmse_sec = cmse_hash->root.root.u.def.section;
if (!_bfd_elf_gc_mark (info, cmse_sec, gc_mark_hook))
return FALSE;
}
}
}
}
first_bfd_browse = FALSE;
}
return TRUE;
@ -17855,6 +18188,9 @@ elf32_arm_swap_symbol_in (bfd * abfd,
const void *pshn,
Elf_Internal_Sym *dst)
{
Elf_Internal_Shdr *symtab_hdr;
const char *name = NULL;
if (!bfd_elf32_swap_symbol_in (abfd, psrc, pshn, dst))
return FALSE;
dst->st_target_internal = 0;
@ -17883,6 +18219,13 @@ elf32_arm_swap_symbol_in (bfd * abfd,
else
ARM_SET_SYM_BRANCH_TYPE (dst->st_target_internal, ST_BRANCH_UNKNOWN);
/* Mark CMSE special symbols. */
symtab_hdr = & elf_symtab_hdr (abfd);
if (symtab_hdr->sh_size)
name = bfd_elf_sym_name (abfd, symtab_hdr, dst, NULL);
if (name && CONST_STRNEQ (name, CMSE_PREFIX))
ARM_SET_SYM_CMSE_SPCL (dst->st_target_internal);
return TRUE;
}

View File

@ -1,3 +1,8 @@
2016-08-04 Thomas Preud'homme <thomas.preudhomme@arm.com>
* arm.h (ARM_GET_SYM_CMSE_SPCL): Define macro.
(ARM_SET_SYM_CMSE_SPCL): Likewise.
2016-08-01 Andrew Jenner <andrew@codesourcery.com>
* opcode/ppc.h (PPC_OPCODE_E200Z4): New define.

View File

@ -384,4 +384,11 @@ enum arm_st_branch_type {
| ((TYPE) & ENUM_ARM_ST_BRANCH_TYPE_BITMASK))
#endif
/* Get or set whether a symbol is a special symbol of an entry function of CMSE
secure code. */
#define ARM_GET_SYM_CMSE_SPCL(SYM_TARGET_INTERNAL) \
(((SYM_TARGET_INTERNAL) >> 2) & 1)
#define ARM_SET_SYM_CMSE_SPCL(SYM_TARGET_INTERNAL) \
(SYM_TARGET_INTERNAL) |= 4
#endif /* _ELF_ARM_H */

View File

@ -1,3 +1,18 @@
2016-08-04 Thomas Preud'homme <thomas.preudhomme@arm.com>
* ld.texinfo (Placement of SG veneers): New concept entry.
* testsuite/ld-arm/arm-elf.exp
(Secure gateway veneers: no .gnu.sgstubs section): New test.
(Secure gateway veneers: wrong entry functions): Likewise.
(Secure gateway veneers (ARMv8-M Baseline)): Likewise.
(Secure gateway veneers (ARMv8-M Mainline)): Likewise.
* testsuite/ld-arm/cmse-veneers.s: New file.
* testsuite/ld-arm/cmse-veneers.d: Likewise.
* testsuite/ld-arm/cmse-veneers.rd: Likewise.
* testsuite/ld-arm/cmse-veneers.sd: Likewise.
* testsuite/ld-arm/cmse-veneers-no-gnu_sgstubs.out: Likewise.
* testsuite/ld-arm/cmse-veneers-wrong-entryfct.out: Likewise.
2016-08-02 Nick Clifton <nickc@redhat.com>
PR ld/17739

View File

@ -6853,6 +6853,12 @@ entries which only support 512Mb of code.
The @samp{--no-apply-dynamic-relocs} option makes AArch64 linker do not apply
link-time values for dynamic relocations.
@cindex Placement of SG veneers
All SG veneers are placed in the special output section @code{.gnu.sgstubs}.
Its start address must be set, either with the command line option
@samp{--section-start} or in a linker script, to indicate where to place these
veneers in memory.
@ifclear GENERIC
@lowersections
@end ifclear

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@ -642,6 +642,33 @@ set armeabitests_nonacl {
{{objdump -d jump-reloc-veneers-long.d}}
"jump-reloc-veneers-long"}
{"Secure gateway veneers: no .gnu.sgstubs section" "" ""
"-march=armv8-m.base -mthumb"
{cmse-veneers.s}
{{ld cmse-veneers-no-gnu_sgstubs.out}}
"cmse-veneers-no-gnu_sgstubs"}
{"Secure gateway veneers: wrong entry functions" "" ""
"-march=armv7-m -mthumb --defsym CHECK_ERRORS=1"
{cmse-veneers.s}
{{ld cmse-veneers-wrong-entryfct.out}}
"cmse-veneers-wrong-entryfct"}
{"Secure gateway veneers (ARMv8-M Baseline)"
"-Ttext=0x8000 --section-start .gnu.sgstubs=0x20000 --gc-sections" ""
"-march=armv8-m.base -mthumb"
{cmse-veneers.s}
{{objdump {-d -j .gnu.sgstubs} cmse-veneers.d}
{objdump {-h -j .gnu.sgstubs} cmse-veneers.sd}
{nm {} cmse-veneers.rd}}
"cmse-veneers-baseline"}
{"Secure gateway veneers (ARMv8-M Mainline)"
"-Ttext=0x8000 --section-start .gnu.sgstubs=0x20000 --gc-sections" ""
"-march=armv8-m.main -mthumb"
{cmse-veneers.s}
{{objdump {-d -j .gnu.sgstubs} cmse-veneers.d}
{objdump {-h -j .gnu.sgstubs} cmse-veneers.sd}
{nm {} cmse-veneers.rd}}
"cmse-veneers-mainline"}
{"R_ARM_THM_JUMP19 Relocation veneers: Short"
"--section-start destsect=0x000108002 --section-start .text=0x8000" ""
"-march=armv7-m -mthumb"

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@ -0,0 +1,3 @@
.*: No address assigned to the veneers output section .gnu.sgstubs
.*: cannot size stub section: Invalid operation
#...

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@ -0,0 +1,19 @@
.*: .*: Special symbol `__acle_se_loc_entry_veneer1' only allowed for ARMv8-M architecture or later.
.*: .*: invalid .* symbol `.*loc_entry_veneer1'.
.*: It must be a global or weak function symbol.
.*: .*: invalid special symbol `__acle_se_loc_entry_veneer2'.
.*: It must be a global or weak function symbol.
.*: .*: invalid special symbol `__acle_se_loc_entry_veneer4'.
.*: It must be a global or weak function symbol.
.*: .*: invalid standard symbol `loc_entry_veneer3'.
.*: It must be a global or weak function symbol.
.*: .*: invalid standard symbol `loc_entry_veneer5'.
.*: It must be a global or weak function symbol.
.*: .*: absent standard symbol `fake_entry_veneer1'.
.*: .*: invalid standard symbol `obj_entry_veneer1'.
.*: It must be a global or weak function symbol.
.*: .*: invalid special symbol `__acle_se_obj_entry_veneer2'.
.*: It must be a global or weak function symbol.
.*: .*: `fake_entry_veneer2' and its special symbol are in different sections.
.*: cannot size stub section: Invalid operation
#...

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@ -0,0 +1,21 @@
.*
Disassembly of section \.gnu.sgstubs:
00020000 <glob_entry_veneer2>:
20000: e97f e97f sg
20004: f7e8 b800 b\.w 8008 <__acle_se_glob_entry_veneer2>
00020008 <weak_entry_veneer2>:
20008: e97f e97f sg
2000c: f7e7 bffe b\.w 800c <__acle_se_weak_entry_veneer2>
00020010 <glob_entry_veneer1>:
20010: e97f e97f sg
20014: f7e7 bff4 b\.w 8000 <__acle_se_glob_entry_veneer1>
00020018 <weak_entry_veneer1>:
20018: e97f e97f sg
2001c: f7e7 bff2 b\.w 8004 <__acle_se_weak_entry_veneer1>

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@ -0,0 +1,9 @@
#...
[0-9a-f]+ T glob_entry_fct
#...
[0-9a-f]+ T glob_entry_veneer1
[0-9a-f]+ T glob_entry_veneer2
#...
[0-9a-f]+ W weak_entry_veneer1
[0-9a-f]+ W weak_entry_veneer2
#...

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@ -0,0 +1,97 @@
.syntax unified
.thumb
.file "foo.c"
.text
.macro decltype name, type
.ifc \type,object
.data
.else
.thumb
.thumb_func
.endif
.type \name, %\type
.endm
.macro entry name, type, vis, typespc, visspc, entry_fct
.align 2
.ifb \visspc
.\vis __acle_se_\name
.else
.\visspc __acle_se_\name
.endif
.\vis \name
.thumb
.thumb_func
.ifb \typespc
decltype __acle_se_\name, \type
.else
decltype __acle_se_\name, \typespc
.endif
decltype \name, \type
__acle_se_\name:
\entry_fct
\name:
.ifc \type,object
.word 42
.else
nop
.endif
.size \name, .-\name
.size __acle_se_\name, .-__acle_se_\name
.endm
.ifndef CHECK_ERRORS
@ Valid setups for veneer generation
entry glob_entry_veneer1, function, global
entry weak_entry_veneer1, function, weak
entry glob_entry_veneer2, function, global, visspc=weak
entry weak_entry_veneer2, function, weak, visspc=global
@ Valid setup for entry function without SG veneer
entry glob_entry_fct, function, global, entry_fct=nop
.else
@ Invalid setups for veneer generation (visibility)
entry loc_entry_veneer1, function, local
entry loc_entry_veneer2, function, global, visspc=local
entry loc_entry_veneer3, function, local, visspc=global
entry loc_entry_veneer4, function, weak, visspc=local
entry loc_entry_veneer5, function, local, visspc=weak
@ Invalid setups for veneer generation (absent standard symbol)
.align 2
.global __acle_se_fake_entry_veneer1
.thumb
.thumb_func
.type __acle_se_fake_entry_veneer1, %function
__acle_se_fake_entry_veneer1:
nop
.size __acle_se_fake_entry_veneer1, .-__acle_se_fake_entry_veneer1
@ Invalid setups for veneer generation (type)
entry obj_entry_veneer1, object, global, typespc=function
entry obj_entry_veneer2, function, global, typespc=object
@ Invalid setup for veneer generation (sections)
.section .text.sub1
.align 2
.thumb
.thumb_func
.global __acle_se_fake_entry_veneer2
.type __acle_se_fake_entry_veneer2, %function
__acle_se_fake_entry_veneer2:
nop
.size __acle_se_fake_entry_veneer2, .-__acle_se_fake_entry_veneer2
.section .text.sub2
.align 2
.thumb
.thumb_func
.global fake_entry_veneer2
.type fake_entry_veneer2, %function
fake_entry_veneer2:
nop
.size fake_entry_veneer2, .-fake_entry_veneer2
.endif

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@ -0,0 +1,7 @@
.*
Sections:
Idx Name Size VMA LMA File off Algn
\d+ \.gnu\.sgstubs 00000020 00020000 00020000 00010000 2\*\*5
CONTENTS, ALLOC, LOAD, READONLY, CODE