From cd40594f59c881ed3a0ead4a98934d48df061c64 Mon Sep 17 00:00:00 2001
From: Srinath Parvathaneni <srinath.parvathaneni@arm.com>
Date: Tue, 2 Jul 2019 14:48:40 +0100
Subject: [PATCH] Ensure that debug information for ARM security functions is
not dropped by the linker when performing garbage collection.
onsider a file containing only Armv8-M secure entry functions.
This file is compiled and linked with "-march=armv8-m.main -mfloat-abi=hard
-mfpu=fpv5-sp-d16 -mcmse -static --specs=rdimon.specs
-Wl,--section-start,.gnu.sgstubs=0x190000 -ffunction-sections
-fdata-sections
-Wl,--gc-sections -g" options to generate an executable.
The executable generated does not contain any debug information of these
secure entry
functions even though it contains secure entry functions in the .text
section.
Example:
$ cat main.c
int main (void)
{
return 0;
}
$ cat sec.c
void __attribute__((cmse_nonsecure_entry))
SecureLED_On ()
{
}
Generate the object files "main.o" and "sec.o" for above test, using
below command.
1. $ arm-none-eabi-gcc -march=armv8-m.main -mfloat-abi=hard
-mfpu=fpv5-sp-d16 -mcmse
-static --specs=rdimon.specs -ffunction-sections -fdata-sections main.c
sec.c -g -c
Using linker, generate the executable for above generated object files.
2.$ arm-none-eabi-ld --section-start .gnu.sgstubs=0x190000 --gc-sections
main.o sec.o -e0 -o main_sec.out
Check for "SecureLED_On" in dwarf information generated for executable
"main_sec.out".
3. $ arm-none-eabi-objdump --dwarf=info main_sec.out |grep "SecureLED_On"
There is no match for the function "SecureLED_On" in .dwarf_info.
After applying this patch and performing above steps 2 and 3, the output is:
<8f> DW_AT_name : (indirect string, offset: 0x9d):
SecureLED_On
This patch fixes the linker by marking all the debug sections (setting
gc_mark to 1)
when .text section containing secure entry functions is marked.
bfd * elf32-arm.c (elf32_arm_gc_mark_extra_sections): Mark debug
sections when .text section contain secure entry functions
is marked.
ld * testsuite/ld-arm/arm-elf.exp: Add tests.
* testsuite/ld-arm/cmse_main.s: New test.
* testsuite/ld-arm/cmse_main_sec_debug.d: Likewise.
* testsuite/ld-arm/cmse_sec_debug.s: Likewise.
---
bfd/ChangeLog | 6 +
bfd/elf32-arm.c | 18 +++
ld/ChangeLog | 7 ++
ld/testsuite/ld-arm/arm-elf.exp | 6 +
ld/testsuite/ld-arm/cmse_main.s | 21 ++++
ld/testsuite/ld-arm/cmse_main_sec_debug.d | 29 +++++
ld/testsuite/ld-arm/cmse_sec_debug.s | 142 ++++++++++++++++++++++
7 files changed, 229 insertions(+)
create mode 100644 ld/testsuite/ld-arm/cmse_main.s
create mode 100644 ld/testsuite/ld-arm/cmse_main_sec_debug.d
create mode 100644 ld/testsuite/ld-arm/cmse_sec_debug.s
#diff --git a/bfd/ChangeLog b/bfd/ChangeLog
#index b0167fe25f..c8f87ba8d2 100644
#--- a/bfd/ChangeLog
#+++ b/bfd/ChangeLog
#@@ -1,3 +1,9 @@
#+2019-07-02 Srinath Parvathaneni <srinath.parvathaneni@arm.com>
#+
#+ * elf32-arm.c (elf32_arm_gc_mark_extra_sections): Mark debug
#+ sections when .text section contain secure entry functions
#+ is marked.
#+
# 2019-06-24 H.J. Lu <hongjiu.lu@intel.com>
#
# PR ld/24721
diff --git a/bfd/elf32-arm.c b/bfd/elf32-arm.c
index 28ee9d55a8..f558d81829 100644
--- a/bfd/elf32-arm.c
+++ b/bfd/elf32-arm.c
@@ -15698,6 +15698,8 @@ elf32_arm_gc_mark_extra_sections (struct bfd_link_info *info,
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_boolean debug_sec_need_to_be_marked = FALSE;
+ asection *isec;
_bfd_elf_gc_mark_extra_sections (info, gc_mark_hook);
@@ -15759,8 +15761,24 @@ elf32_arm_gc_mark_extra_sections (struct bfd_link_info *info,
if (!cmse_sec->gc_mark
&& !_bfd_elf_gc_mark (info, cmse_sec, gc_mark_hook))
return FALSE;
+ /* The debug sections related to these secure entry
+ functions are marked on enabling below flag. */
+ debug_sec_need_to_be_marked = TRUE;
}
}
+ if (debug_sec_need_to_be_marked)
+ {
+ /* Looping over all the sections of the object file containing
+ Armv8-M secure entry functions and marking all the debug
+ sections. */
+ for (isec = sub->sections; isec != NULL; isec = isec->next)
+ {
+ /* If not a debug sections, skip it. */
+ if (!isec->gc_mark && (isec->flags & SEC_DEBUGGING))
+ isec->gc_mark = 1 ;
+ }
+ debug_sec_need_to_be_marked = FALSE;
+ }
}
}
first_bfd_browse = FALSE;
#diff --git a/ld/ChangeLog b/ld/ChangeLog
#index 73bee92dab..95e6cf7fda 100644
#--- a/ld/ChangeLog
#+++ b/ld/ChangeLog
#@@ -1,3 +1,10 @@
#+2019-07-02 Srinath Parvathaneni <srinath.parvathaneni@arm.com>
#+
#+ * testsuite/ld-arm/arm-elf.exp: Add tests.
#+ * testsuite/ld-arm/cmse_main.s: New test.
#+ * testsuite/ld-arm/cmse_main_sec_debug.d: Likewise.
#+ * testsuite/ld-arm/cmse_sec_debug.s: Likewise.
#+
# 2019-06-24 H.J. Lu <hongjiu.lu@intel.com>
#
# PR ld/24721
diff --git a/ld/testsuite/ld-arm/arm-elf.exp b/ld/testsuite/ld-arm/arm-elf.exp
index 450a76b708..440a1568c2 100644
--- a/ld/testsuite/ld-arm/arm-elf.exp
+++ b/ld/testsuite/ld-arm/arm-elf.exp
@@ -768,6 +768,12 @@ set armeabitests_nonacl {
{cmse-implib.s}
{{ld cmse-new-wrong-implib.out}}
"cmse-new-wrong-implib"}
+ {"Secure gateway veneers:cmse functions debug information missing"
+ "--section-start .gnu.sgstubs=0x190000 --gc-sections -e0" ""
+ "-march=armv8-m.main -mthumb"
+ {cmse_main.s cmse_sec_debug.s}
+ {{objdump --dwarf=info cmse_main_sec_debug.d}}
+ "cmse_main_sec_debug"}
{"R_ARM_THM_JUMP19 Relocation veneers: Short"
"--section-start destsect=0x000108002 --section-start .text=0x8000" ""
diff --git a/ld/testsuite/ld-arm/cmse_main.s b/ld/testsuite/ld-arm/cmse_main.s
new file mode 100644
index 0000000000..5047c02f46
--- /dev/null
+++ b/ld/testsuite/ld-arm/cmse_main.s
@@ -0,0 +1,21 @@
+ .arch armv8-m.main
+ .file "cmse_main.c"
+ .text
+.Ltext0:
+ .cfi_sections .debug_frame
+ .section .text.main,"ax",%progbits
+ .align 1
+ .global main
+ .arch armv8-m.main
+ .syntax unified
+ .thumb
+ .thumb_func
+ .fpu fpv5-sp-d16
+ .type main, %function
+main:
+.LFB0:
+ .file 1 "cmse_main.c"
+ .loc 1 2 1
+ .cfi_startproc
+ .cfi_endproc
+.LFE0:
diff --git a/ld/testsuite/ld-arm/cmse_main_sec_debug.d b/ld/testsuite/ld-arm/cmse_main_sec_debug.d
new file mode 100644
index 0000000000..61280b769c
--- /dev/null
+++ b/ld/testsuite/ld-arm/cmse_main_sec_debug.d
@@ -0,0 +1,29 @@
+
+tmpdir/cmse_main_sec_debug: .*
+
+Contents of the \.debug_info section:
+
+ Compilation Unit @ offset 0x0:
+ Length: 0x34 \(32-bit\)
+ Version: 4
+ Abbrev Offset: 0x0
+ Pointer Size: 4
+ <0><b>: Abbrev Number: 1 \(DW_TAG_compile_unit\)
+ <c> DW_AT_producer : \(indirect string, offset: 0x6\): GNU C17 10.0.0 20190617
+ <10> DW_AT_language : 12 \(ANSI C99\)
+ <11> DW_AT_name : \(indirect string, offset: 0x0\): sec.c
+ <15> DW_AT_comp_dir : \(indirect string, offset: 0x2b\): Blinky
+ <19> DW_AT_ranges : 0x0
+ <1d> DW_AT_low_pc : 0x0
+ <21> DW_AT_stmt_list : 0x0
+ <1><25>: Abbrev Number: 2 \(DW_TAG_subprogram\)
+ <26> DW_AT_external : 1
+ <26> DW_AT_name : \(indirect string, offset: 0x1e\): SecureLED_On
+ <2a> DW_AT_decl_file : 1
+ <2b> DW_AT_decl_line : 2
+ <2c> DW_AT_decl_column : 1
+ <2d> DW_AT_low_pc : 0x8000
+ <31> DW_AT_high_pc : 0xc
+ <35> DW_AT_frame_base : 1 byte block: 9c \(DW_OP_call_frame_cfa\)
+ <37> DW_AT_GNU_all_call_sites: 1
+ <1><37>: Abbrev Number: 0
diff --git a/ld/testsuite/ld-arm/cmse_sec_debug.s b/ld/testsuite/ld-arm/cmse_sec_debug.s
new file mode 100644
index 0000000000..0ca949e3e5
--- /dev/null
+++ b/ld/testsuite/ld-arm/cmse_sec_debug.s
@@ -0,0 +1,142 @@
+ .arch armv8-m.main
+ .file "sec.c"
+ .text
+.Ltext0:
+ .cfi_sections .debug_frame
+ .section .text.SecureLED_On,"ax",%progbits
+ .align 1
+ .global SecureLED_On
+ .global __acle_se_SecureLED_On
+ .arch armv8-m.main
+ .syntax unified
+ .thumb
+ .thumb_func
+ .fpu fpv5-sp-d16
+ .type __acle_se_SecureLED_On, %function
+ .syntax unified
+ .thumb
+ .thumb_func
+ .fpu fpv5-sp-d16
+ .type SecureLED_On, %function
+SecureLED_On:
+__acle_se_SecureLED_On:
+.LFB0:
+ .file 1 "sec.c"
+ .loc 1 3 1
+ .cfi_startproc
+ push {r7}
+ .cfi_def_cfa_offset 4
+ .cfi_offset 7, -4
+ add r7, sp, #0
+ .cfi_def_cfa_register 7
+ .loc 1 4 1
+ mov sp, r7
+ .cfi_def_cfa_register 13
+ ldr r7, [sp], #4
+ .cfi_restore 7
+ .cfi_def_cfa_offset 0
+ bxns lr
+ .cfi_endproc
+.LFE0:
+ .size SecureLED_On, .-SecureLED_On
+ .text
+.Letext0:
+ .section .debug_info,"",%progbits
+.Ldebug_info0:
+ .4byte 0x34
+ .2byte 0x4
+ .4byte .Ldebug_abbrev0
+ .byte 0x4
+ .uleb128 0x1
+ .4byte .LASF0
+ .byte 0xc
+ .4byte .LASF1
+ .4byte .LASF2
+ .4byte .Ldebug_ranges0+0
+ .4byte 0
+ .4byte .Ldebug_line0
+ .uleb128 0x2
+ .4byte .LASF3
+ .byte 0x1
+ .byte 0x2
+ .byte 0x1
+ .4byte .LFB0
+ .4byte .LFE0-.LFB0
+ .uleb128 0x1
+ .byte 0x9c
+ .byte 0
+ .section .debug_abbrev,"",%progbits
+.Ldebug_abbrev0:
+ .uleb128 0x1
+ .uleb128 0x11
+ .byte 0x1
+ .uleb128 0x25
+ .uleb128 0xe
+ .uleb128 0x13
+ .uleb128 0xb
+ .uleb128 0x3
+ .uleb128 0xe
+ .uleb128 0x1b
+ .uleb128 0xe
+ .uleb128 0x55
+ .uleb128 0x17
+ .uleb128 0x11
+ .uleb128 0x1
+ .uleb128 0x10
+ .uleb128 0x17
+ .byte 0
+ .byte 0
+ .uleb128 0x2
+ .uleb128 0x2e
+ .byte 0
+ .uleb128 0x3f
+ .uleb128 0x19
+ .uleb128 0x3
+ .uleb128 0xe
+ .uleb128 0x3a
+ .uleb128 0xb
+ .uleb128 0x3b
+ .uleb128 0xb
+ .uleb128 0x39
+ .uleb128 0xb
+ .uleb128 0x11
+ .uleb128 0x1
+ .uleb128 0x12
+ .uleb128 0x6
+ .uleb128 0x40
+ .uleb128 0x18
+ .uleb128 0x2117
+ .uleb128 0x19
+ .byte 0
+ .byte 0
+ .byte 0
+ .section .debug_aranges,"",%progbits
+ .4byte 0x1c
+ .2byte 0x2
+ .4byte .Ldebug_info0
+ .byte 0x4
+ .byte 0
+ .2byte 0
+ .2byte 0
+ .4byte .LFB0
+ .4byte .LFE0-.LFB0
+ .4byte 0
+ .4byte 0
+ .section .debug_ranges,"",%progbits
+.Ldebug_ranges0:
+ .4byte .LFB0
+ .4byte .LFE0
+ .4byte 0
+ .4byte 0
+ .section .debug_line,"",%progbits
+.Ldebug_line0:
+ .section .debug_str,"MS",%progbits,1
+.LASF1:
+ .ascii "sec.c\000"
+.LASF0:
+ .ascii "GNU C17 10.0.0 20190617\000"
+.LASF3:
+ .ascii "SecureLED_On\000"
+.LASF2:
+ .ascii "Blinky\000"
+ .ident "GCC: (GNU) 10.0.0 20190617 (experimental)"
--
2.22.0
