[PATCH 4.19 47/58] perf jit: Include program header in ELF files

From: Greg Kroah-Hartman
Date: Mon Sep 26 2022 - 06:32:04 EST


From: Lieven Hey <lieven.hey@xxxxxxxx>

[ Upstream commit babd04386b1df8c364cdaa39ac0e54349502e1e5 ]

The missing header makes it hard for programs like elfutils to open
these files.

Fixes: 2d86612aacb7805f ("perf symbol: Correct address for bss symbols")
Reviewed-by: Leo Yan <leo.yan@xxxxxxxxxx>
Signed-off-by: Lieven Hey <lieven.hey@xxxxxxxx>
Tested-by: Leo Yan <leo.yan@xxxxxxxxxx>
Cc: Leo Yan <leo.yan@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20220915092910.711036-1-lieven.hey@xxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
tools/perf/util/genelf.c | 14 ++++++++++++++
tools/perf/util/genelf.h | 4 ++++
2 files changed, 18 insertions(+)

diff --git a/tools/perf/util/genelf.c b/tools/perf/util/genelf.c
index afb8fe3a8e35..65e41e259af8 100644
--- a/tools/perf/util/genelf.c
+++ b/tools/perf/util/genelf.c
@@ -256,6 +256,7 @@ jit_write_elf(int fd, uint64_t load_addr, const char *sym,
Elf_Data *d;
Elf_Scn *scn;
Elf_Ehdr *ehdr;
+ Elf_Phdr *phdr;
Elf_Shdr *shdr;
uint64_t eh_frame_base_offset;
char *strsym = NULL;
@@ -290,6 +291,19 @@ jit_write_elf(int fd, uint64_t load_addr, const char *sym,
ehdr->e_version = EV_CURRENT;
ehdr->e_shstrndx= unwinding ? 4 : 2; /* shdr index for section name */

+ /*
+ * setup program header
+ */
+ phdr = elf_newphdr(e, 1);
+ phdr[0].p_type = PT_LOAD;
+ phdr[0].p_offset = 0;
+ phdr[0].p_vaddr = 0;
+ phdr[0].p_paddr = 0;
+ phdr[0].p_filesz = csize;
+ phdr[0].p_memsz = csize;
+ phdr[0].p_flags = PF_X | PF_R;
+ phdr[0].p_align = 8;
+
/*
* setup text section
*/
diff --git a/tools/perf/util/genelf.h b/tools/perf/util/genelf.h
index de322d51c7fe..23a7401a63d0 100644
--- a/tools/perf/util/genelf.h
+++ b/tools/perf/util/genelf.h
@@ -41,8 +41,10 @@ int jit_add_debug_info(Elf *e, uint64_t code_addr, void *debug, int nr_debug_ent

#if GEN_ELF_CLASS == ELFCLASS64
#define elf_newehdr elf64_newehdr
+#define elf_newphdr elf64_newphdr
#define elf_getshdr elf64_getshdr
#define Elf_Ehdr Elf64_Ehdr
+#define Elf_Phdr Elf64_Phdr
#define Elf_Shdr Elf64_Shdr
#define Elf_Sym Elf64_Sym
#define ELF_ST_TYPE(a) ELF64_ST_TYPE(a)
@@ -50,8 +52,10 @@ int jit_add_debug_info(Elf *e, uint64_t code_addr, void *debug, int nr_debug_ent
#define ELF_ST_VIS(a) ELF64_ST_VISIBILITY(a)
#else
#define elf_newehdr elf32_newehdr
+#define elf_newphdr elf32_newphdr
#define elf_getshdr elf32_getshdr
#define Elf_Ehdr Elf32_Ehdr
+#define Elf_Phdr Elf32_Phdr
#define Elf_Shdr Elf32_Shdr
#define Elf_Sym Elf32_Sym
#define ELF_ST_TYPE(a) ELF32_ST_TYPE(a)
--
2.35.1