From ccd2d9df6e21581dfed3e6dffb3b6f1b7efd1a26 Mon Sep 17 00:00:00 2001 From: Max Filippov Date: Fri, 3 Jun 2022 20:44:06 -0700 Subject: [PATCH 1/2] xtensa: clean up ELF_PLAT_INIT macro Wrap _r in parentheses in the macro body. Signed-off-by: Max Filippov --- arch/xtensa/include/asm/elf.h | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/arch/xtensa/include/asm/elf.h b/arch/xtensa/include/asm/elf.h index 909a6ab4f22b..9c21897c6992 100644 --- a/arch/xtensa/include/asm/elf.h +++ b/arch/xtensa/include/asm/elf.h @@ -153,10 +153,15 @@ typedef elf_fpreg_t elf_fpregset_t[ELF_NFPREG]; */ #define ELF_PLAT_INIT(_r, load_addr) \ - do { _r->areg[0]=0; /*_r->areg[1]=0;*/ _r->areg[2]=0; _r->areg[3]=0; \ - _r->areg[4]=0; _r->areg[5]=0; _r->areg[6]=0; _r->areg[7]=0; \ - _r->areg[8]=0; _r->areg[9]=0; _r->areg[10]=0; _r->areg[11]=0; \ - _r->areg[12]=0; _r->areg[13]=0; _r->areg[14]=0; _r->areg[15]=0; \ + do { \ + (_r)->areg[0] = 0; /*(_r)->areg[1] = 0;*/ \ + (_r)->areg[2] = 0; (_r)->areg[3] = 0; \ + (_r)->areg[4] = 0; (_r)->areg[5] = 0; \ + (_r)->areg[6] = 0; (_r)->areg[7] = 0; \ + (_r)->areg[8] = 0; (_r)->areg[9] = 0; \ + (_r)->areg[10] = 0; (_r)->areg[11] = 0; \ + (_r)->areg[12] = 0; (_r)->areg[13] = 0; \ + (_r)->areg[14] = 0; (_r)->areg[15] = 0; \ } while (0) typedef struct { From e3ddb8bbe0f8cc994748c81e17acc58fda6f8abe Mon Sep 17 00:00:00 2001 From: Max Filippov Date: Fri, 3 Jun 2022 11:31:14 -0700 Subject: [PATCH 2/2] 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 --- arch/xtensa/include/asm/elf.h | 11 +++++++++++ arch/xtensa/include/asm/processor.h | 3 +++ arch/xtensa/include/uapi/asm/ptrace.h | 4 ++++ fs/Kconfig.binfmt | 2 +- 4 files changed, 19 insertions(+), 1 deletion(-) 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