diff --git a/arch/sandbox/cpu/os.c b/arch/sandbox/cpu/os.c index a8d01e4001..c20491493f 100644 --- a/arch/sandbox/cpu/os.c +++ b/arch/sandbox/cpu/os.c @@ -786,3 +786,40 @@ int os_mprotect_allow(void *start, size_t len) return mprotect(start, len, PROT_READ | PROT_WRITE); } + +void *os_find_text_base(void) +{ + char line[500]; + void *base = NULL; + int len; + int fd; + + /* + * This code assumes that the first line of /proc/self/maps holds + * information about the text, for example: + * + * 5622d9907000-5622d9a55000 r-xp 00000000 08:01 15067168 u-boot + * + * The first hex value is assumed to be the address. + * + * This is tested in Linux 4.15. + */ + fd = open("/proc/self/maps", O_RDONLY); + if (fd == -1) + return NULL; + len = read(fd, line, sizeof(line)); + if (len > 0) { + char *end = memchr(line, '-', len); + + if (end) { + unsigned long long addr; + + *end = '\0'; + if (sscanf(line, "%llx", &addr) == 1) + base = (void *)addr; + } + } + close(fd); + + return base; +} diff --git a/arch/sandbox/cpu/start.c b/arch/sandbox/cpu/start.c index 2f5e6e9518..e22d65f6d9 100644 --- a/arch/sandbox/cpu/start.c +++ b/arch/sandbox/cpu/start.c @@ -328,6 +328,10 @@ int main(int argc, char *argv[]) gd_t data; int ret; + memset(&data, '\0', sizeof(data)); + gd = &data; + gd->arch.text_base = os_find_text_base(); + ret = state_init(); if (ret) goto err; @@ -340,8 +344,6 @@ int main(int argc, char *argv[]) if (ret) goto err; - memset(&data, '\0', sizeof(data)); - gd = &data; #if CONFIG_VAL(SYS_MALLOC_F_LEN) gd->malloc_base = CONFIG_MALLOC_F_ADDR; #endif @@ -350,6 +352,12 @@ int main(int argc, char *argv[]) #endif setup_ram_buf(state); + /* + * Set up the relocation offset here, since sandbox symbols are always + * relocated by the OS before sandbox is entered. + */ + gd->reloc_off = (ulong)gd->arch.text_base; + /* Do pre- and post-relocation init */ board_init_f(0); diff --git a/arch/sandbox/include/asm/global_data.h b/arch/sandbox/include/asm/global_data.h index f6a6a343d2..f4ce72d566 100644 --- a/arch/sandbox/include/asm/global_data.h +++ b/arch/sandbox/include/asm/global_data.h @@ -12,6 +12,7 @@ /* Architecture-specific global data */ struct arch_global_data { uint8_t *ram_buf; /* emulated RAM buffer */ + void *text_base; /* pointer to base of text region */ }; #include diff --git a/board/sandbox/README.sandbox b/board/sandbox/README.sandbox index 9b09404294..ed8fac6f78 100644 --- a/board/sandbox/README.sandbox +++ b/board/sandbox/README.sandbox @@ -392,6 +392,49 @@ state_setprop() which does this automatically and avoids running out of space. See existing code for examples. +Debugging the init sequence +--------------------------- + +If you get a failure in the initcall sequence, like this: + + initcall sequence 0000560775957c80 failed at call 0000000000048134 (err=-96) + +Then you use can use grep to see which init call failed, e.g.: + + $ grep 0000000000048134 u-boot.map + stdio_add_devices + +Of course another option is to run it with a debugger such as gdb: + + $ gdb u-boot + ... + (gdb) br initcall.h:41 + Breakpoint 1 at 0x4db9d: initcall.h:41. (2 locations) + +Note that two locations are reported, since this function is used in both +board_init_f() and board_init_r(). + + (gdb) r + Starting program: /tmp/b/sandbox/u-boot + [Thread debugging using libthread_db enabled] + Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1". + + U-Boot 2018.09-00264-ge0c2ba9814-dirty (Sep 22 2018 - 12:21:46 -0600) + + DRAM: 128 MiB + MMC: + + Breakpoint 1, initcall_run_list (init_sequence=0x5555559619e0 ) + at /scratch/sglass/cosarm/src/third_party/u-boot/files/include/initcall.h:41 + 41 printf("initcall sequence %p failed at call %p (err=%d)\n", + (gdb) print *init_fnc_ptr + $1 = (const init_fnc_t) 0x55555559c114 + (gdb) + + +This approach can be used on normal boards as well as sandbox. + + Testing ------- diff --git a/common/board_f.c b/common/board_f.c index 149a7229e8..7ef20f2042 100644 --- a/common/board_f.c +++ b/common/board_f.c @@ -714,7 +714,7 @@ static int setup_reloc(void) * just after the default vector table location, so at 0x400 */ gd->reloc_off = gd->relocaddr - (CONFIG_SYS_TEXT_BASE + 0x400); -#else +#elif !defined(CONFIG_SANDBOX) gd->reloc_off = gd->relocaddr - CONFIG_SYS_TEXT_BASE; #endif #endif diff --git a/include/initcall.h b/include/initcall.h index 3ac01aa2cd..a38c83efa4 100644 --- a/include/initcall.h +++ b/include/initcall.h @@ -22,13 +22,17 @@ static inline int initcall_run_list(const init_fnc_t init_sequence[]) unsigned long reloc_ofs = 0; int ret; - if (gd->flags & GD_FLG_RELOC) + /* + * Sandbox is relocated by the OS, so symbols always appear at + * the relocated address. + */ + if (IS_ENABLED(CONFIG_SANDBOX) || (gd->flags & GD_FLG_RELOC)) reloc_ofs = gd->reloc_off; #ifdef CONFIG_EFI_APP reloc_ofs = (unsigned long)image_base; #endif debug("initcall: %p", (char *)*init_fnc_ptr - reloc_ofs); - if (gd->flags & GD_FLG_RELOC) + if (reloc_ofs) debug(" (relocated to %p)\n", (char *)*init_fnc_ptr); else debug("\n"); diff --git a/include/os.h b/include/os.h index 6f33b08cf0..7a4f78b9b1 100644 --- a/include/os.h +++ b/include/os.h @@ -364,4 +364,15 @@ int os_write_file(const char *name, const void *buf, int size); */ int os_read_file(const char *name, void **bufp, int *sizep); +/* + * os_find_text_base() - Find the text section in this running process + * + * This tries to find the address of the text section in this running process. + * It can be useful to map the address of functions to the address listed in + * the u-boot.map file. + * + * @return address if found, else NULL + */ +void *os_find_text_base(void); + #endif