From: Andrew Burgess Date: Mon, 30 Nov 2020 12:14:38 +0000 (+0000) Subject: bfd/riscv: prepare to handle bare metal core dump creation X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=0897bb7d6dc4e803cd99d4656186c965f099d01c;p=binutils-gdb.git bfd/riscv: prepare to handle bare metal core dump creation When creating a core file GDB will call the function elfcore_write_prstatus to write out the general purpose registers along with the pid/tid for the thread (into a prstatus structure) and the executable name and arguments (into a prpsinfo_t structure). However, for a bare metal RISC-V tool chain the prstatus_t and prpsinfo_t types are not defined so the elfcore_write_prstatus function will return NULL, preventing core file creation. This commit provides the `elf_backend_write_core_note' hook and uses the provided function to write out the required information. In order to keep changes in the non bare metal tools to a minimum, the provided backend function will itself return NULL when the prstatus_t or pspsinfo_t types are available, the consequence of this is that the generic code in elfcore_write_prstatus will be used just as before. But, when prstatus_t or prpsinfo_t is not available, the new backend function will write out the information using predefined offsets. This new functionality will be used by a later GDB commit that will add bare metal core dumps for RISC-V. bfd/ChangeLog: * elfnn-riscv.c (PRPSINFO_PR_FNAME_LENGTH): Define. (PRPSINFO_PR_PSARGS_LENGTH): Define. (riscv_write_core_note): New function. (riscv_elf_grok_psinfo): Make use of two new length defines. (elf_backend_write_core_note): Define. --- diff --git a/bfd/ChangeLog b/bfd/ChangeLog index 31d0714da27..9e7f90e1625 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,12 @@ +2021-03-05 Craig Blackmore + Andrew Burgess + + * elfnn-riscv.c (PRPSINFO_PR_FNAME_LENGTH): Define. + (PRPSINFO_PR_PSARGS_LENGTH): Define. + (riscv_write_core_note): New function. + (riscv_elf_grok_psinfo): Make use of two new length defines. + (elf_backend_write_core_note): Define. + 2021-03-05 Craig Blackmore Andrew Burgess diff --git a/bfd/elfnn-riscv.c b/bfd/elfnn-riscv.c index ec8a3e73c8f..76d29b73332 100644 --- a/bfd/elfnn-riscv.c +++ b/bfd/elfnn-riscv.c @@ -4877,6 +4877,8 @@ _bfd_riscv_relax_section (bfd *abfd, asection *sec, # define PRPSINFO_OFFSET_PR_PID 16 # define PRPSINFO_OFFSET_PR_FNAME 32 # define PRPSINFO_OFFSET_PR_PSARGS 48 +# define PRPSINFO_PR_FNAME_LENGTH 16 +# define PRPSINFO_PR_PSARGS_LENGTH 80 #else # define PRSTATUS_SIZE 376 # define PRSTATUS_OFFSET_PR_CURSIG 12 @@ -4887,8 +4889,83 @@ _bfd_riscv_relax_section (bfd *abfd, asection *sec, # define PRPSINFO_OFFSET_PR_PID 24 # define PRPSINFO_OFFSET_PR_FNAME 40 # define PRPSINFO_OFFSET_PR_PSARGS 56 +# define PRPSINFO_PR_FNAME_LENGTH 16 +# define PRPSINFO_PR_PSARGS_LENGTH 80 #endif +/* Write PRSTATUS and PRPSINFO note into core file. This will be called + before the generic code in elf.c. By checking the compiler defines we + only perform any action here if the generic code would otherwise not be + able to help us. The intention is that bare metal core dumps (where the + prstatus_t and/or prpsinfo_t might not be available) will use this code, + while non bare metal tools will use the generic elf code. */ + +static char * +riscv_write_core_note (bfd *abfd ATTRIBUTE_UNUSED, + char *buf ATTRIBUTE_UNUSED, + int *bufsiz ATTRIBUTE_UNUSED, + int note_type ATTRIBUTE_UNUSED, ...) +{ + switch (note_type) + { + default: + return NULL; + +#if !defined (HAVE_PRPSINFO_T) + case NT_PRPSINFO: + { + char data[PRPSINFO_SIZE] ATTRIBUTE_NONSTRING; + va_list ap; + + va_start (ap, note_type); + memset (data, 0, sizeof (data)); + strncpy (data + PRPSINFO_OFFSET_PR_FNAME, va_arg (ap, const char *), + PRPSINFO_PR_FNAME_LENGTH); +#if GCC_VERSION == 8000 || GCC_VERSION == 8001 + DIAGNOSTIC_PUSH; + /* GCC 8.0 and 8.1 warn about 80 equals destination size with + -Wstringop-truncation: + https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85643 + */ + DIAGNOSTIC_IGNORE_STRINGOP_TRUNCATION; +#endif + strncpy (data + PRPSINFO_OFFSET_PR_PSARGS, va_arg (ap, const char *), + PRPSINFO_PR_PSARGS_LENGTH); +#if GCC_VERSION == 8000 || GCC_VERSION == 8001 + DIAGNOSTIC_POP; +#endif + va_end (ap); + return elfcore_write_note (abfd, buf, bufsiz, + "CORE", note_type, data, sizeof (data)); + } +#endif /* !HAVE_PRPSINFO_T */ + +#if !defined (HAVE_PRSTATUS_T) + case NT_PRSTATUS: + { + char data[PRSTATUS_SIZE]; + va_list ap; + long pid; + int cursig; + const void *greg; + + va_start (ap, note_type); + memset (data, 0, sizeof(data)); + pid = va_arg (ap, long); + bfd_put_32 (abfd, pid, data + PRSTATUS_OFFSET_PR_PID); + cursig = va_arg (ap, int); + bfd_put_16 (abfd, cursig, data + PRSTATUS_OFFSET_PR_CURSIG); + greg = va_arg (ap, const void *); + memcpy (data + PRSTATUS_OFFSET_PR_REG, greg, + PRSTATUS_SIZE - PRSTATUS_OFFSET_PR_REG - ARCH_SIZE / 8); + va_end (ap); + return elfcore_write_note (abfd, buf, bufsiz, + "CORE", note_type, data, sizeof (data)); + } +#endif /* !HAVE_PRSTATUS_T */ + } +} + /* Support for core dump NOTE sections. */ static bfd_boolean @@ -4930,11 +5007,13 @@ riscv_elf_grok_psinfo (bfd *abfd, Elf_Internal_Note *note) /* pr_fname */ elf_tdata (abfd)->core->program = _bfd_elfcore_strndup - (abfd, note->descdata + PRPSINFO_OFFSET_PR_FNAME, 16); + (abfd, note->descdata + PRPSINFO_OFFSET_PR_FNAME, + PRPSINFO_PR_FNAME_LENGTH); /* pr_psargs */ elf_tdata (abfd)->core->command = _bfd_elfcore_strndup - (abfd, note->descdata + PRPSINFO_OFFSET_PR_PSARGS, 80); + (abfd, note->descdata + PRPSINFO_OFFSET_PR_PSARGS, + PRPSINFO_PR_PSARGS_LENGTH); break; } @@ -5003,6 +5082,7 @@ riscv_elf_obj_attrs_arg_type (int tag) #define elf_backend_grok_prstatus riscv_elf_grok_prstatus #define elf_backend_grok_psinfo riscv_elf_grok_psinfo #define elf_backend_object_p riscv_elf_object_p +#define elf_backend_write_core_note riscv_write_core_note #define elf_info_to_howto_rel NULL #define elf_info_to_howto riscv_info_to_howto_rela #define bfd_elfNN_bfd_relax_section _bfd_riscv_relax_section