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| author | Max Filippov <jcmvbkbc@gmail.com> | 2022-06-03 11:31:14 -0700 |
|---|---|---|
| committer | Max Filippov <jcmvbkbc@gmail.com> | 2022-09-13 18:28:00 -0700 |
| commit | e3ddb8bbe0f8cc994748c81e17acc58fda6f8abe (patch) | |
| tree | c4a5c648f6622b6c655b3cbd02d7575e30898b58 | |
| parent | ccd2d9df6e21581dfed3e6dffb3b6f1b7efd1a26 (diff) | |
| download | lwn-e3ddb8bbe0f8cc994748c81e17acc58fda6f8abe.tar.gz lwn-e3ddb8bbe0f8cc994748c81e17acc58fda6f8abe.zip | |
xtensa: add FDPIC and static PIE support for noMMU
Define ELFOSABI_XTENSA_FDPIC and use it as an OSABI tag in the ELF
header to distinguish FDPIC ELF files from regular ELF files.
Define ELF_FDPIC_PLAT_INIT and put executable map, interpreter map and
executable dynamic section addresses into registers a4..a6.
Update start_thread macro to preserve register values in the current
register window.
Add definitions for PTRACE_GETFDPIC, PTRACE_GETFDPIC_EXEC and
PTRACE_GETFDPIC_INTERP.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
| -rw-r--r-- | arch/xtensa/include/asm/elf.h | 11 | ||||
| -rw-r--r-- | arch/xtensa/include/asm/processor.h | 3 | ||||
| -rw-r--r-- | arch/xtensa/include/uapi/asm/ptrace.h | 4 | ||||
| -rw-r--r-- | fs/Kconfig.binfmt | 2 |
4 files changed, 19 insertions, 1 deletions
diff --git a/arch/xtensa/include/asm/elf.h b/arch/xtensa/include/asm/elf.h index 9c21897c6992..ffcf1ada19c6 100644 --- a/arch/xtensa/include/asm/elf.h +++ b/arch/xtensa/include/asm/elf.h @@ -93,6 +93,10 @@ typedef elf_fpreg_t elf_fpregset_t[ELF_NFPREG]; #define elf_check_arch(x) ( ( (x)->e_machine == EM_XTENSA ) || \ ( (x)->e_machine == EM_XTENSA_OLD ) ) +#define ELFOSABI_XTENSA_FDPIC 65 +#define elf_check_fdpic(x) ((x)->e_ident[EI_OSABI] == ELFOSABI_XTENSA_FDPIC) +#define ELF_FDPIC_CORE_EFLAGS 0 + /* * These are used to set parameters in the core dumps. */ @@ -164,6 +168,13 @@ typedef elf_fpreg_t elf_fpregset_t[ELF_NFPREG]; (_r)->areg[14] = 0; (_r)->areg[15] = 0; \ } while (0) +#define ELF_FDPIC_PLAT_INIT(_r, _exec_map_addr, _interp_map_addr, dynamic_addr) \ + do { \ + (_r)->areg[4] = _exec_map_addr; \ + (_r)->areg[5] = _interp_map_addr; \ + (_r)->areg[6] = dynamic_addr; \ + } while (0) + typedef struct { xtregs_opt_t opt; xtregs_user_t user; diff --git a/arch/xtensa/include/asm/processor.h b/arch/xtensa/include/asm/processor.h index 76bc63127c66..b75ba16ec080 100644 --- a/arch/xtensa/include/asm/processor.h +++ b/arch/xtensa/include/asm/processor.h @@ -205,9 +205,12 @@ struct thread_struct { #define start_thread(regs, new_pc, new_sp) \ do { \ unsigned long syscall = (regs)->syscall; \ + unsigned long current_aregs[16]; \ + memcpy(current_aregs, (regs)->areg, sizeof(current_aregs)); \ memset((regs), 0, sizeof(*(regs))); \ (regs)->pc = (new_pc); \ (regs)->ps = USER_PS_VALUE; \ + memcpy((regs)->areg, current_aregs, sizeof(current_aregs)); \ (regs)->areg[1] = (new_sp); \ (regs)->areg[0] = 0; \ (regs)->wmask = 1; \ diff --git a/arch/xtensa/include/uapi/asm/ptrace.h b/arch/xtensa/include/uapi/asm/ptrace.h index 50db3e0a6341..9115e86ebc75 100644 --- a/arch/xtensa/include/uapi/asm/ptrace.h +++ b/arch/xtensa/include/uapi/asm/ptrace.h @@ -37,6 +37,10 @@ #define PTRACE_SETXTREGS 19 #define PTRACE_GETHBPREGS 20 #define PTRACE_SETHBPREGS 21 +#define PTRACE_GETFDPIC 22 + +#define PTRACE_GETFDPIC_EXEC 0 +#define PTRACE_GETFDPIC_INTERP 1 #ifndef __ASSEMBLY__ diff --git a/fs/Kconfig.binfmt b/fs/Kconfig.binfmt index 21e154516bf2..9d131a54226f 100644 --- a/fs/Kconfig.binfmt +++ b/fs/Kconfig.binfmt @@ -58,7 +58,7 @@ config ARCH_USE_GNU_PROPERTY config BINFMT_ELF_FDPIC bool "Kernel support for FDPIC ELF binaries" default y if !BINFMT_ELF - depends on ARM || ((M68K || SUPERH) && !MMU) + depends on ARM || ((M68K || SUPERH || XTENSA) && !MMU) select ELFCORE help ELF FDPIC binaries are based on ELF, but allow the individual load |