This patch adds a new pstore command allowing to display or save ramoops logs (oops, panic, console, ftrace and user) generated by a previous kernel crash. PStore parameters can be set in U-Boot configuration file, or at run-time using "pstore set" command. Records size should be the same as the ones used by kernel, and should be a power of 2. This command allows: - to display uncompressed logs - to save compressed or uncompressed logs, compressed logs are saved as a compressed stream, it may need some work to be able to decompress it, e.g. adding a fake header: "printf "\x1f\x8b\x08\x00\x00\x00\x00\x00\x00\x00" | cat - dmesg-ramoops-0.enc.z | gzip -dc" - ECC part is not used to check memory corruption - only 1st FTrace log is displayed or saved
Signed-off-by: Frédéric Danis frederic.danis@collabora.com --- cmd/Kconfig | 63 ++++++++ cmd/Makefile | 1 + cmd/pstore.c | 417 +++++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 481 insertions(+) create mode 100644 cmd/pstore.c
diff --git a/cmd/Kconfig b/cmd/Kconfig index cf982ff65e..7e28100b98 100644 --- a/cmd/Kconfig +++ b/cmd/Kconfig @@ -1675,6 +1675,69 @@ config CMD_QFW feature is to allow easy loading of files passed to qemu-system via -kernel / -initrd
+config CMD_PSTORE + bool "pstore" + help + This provides access to Linux PStore. The main feature is to allow to + display or save PStore records. + +config CMD_PSTORE_ADDR + hex "Mem Address" + depends on CMD_PSTORE + default "0x0" + help + Base addr used for PStore ramoops memory, should be identical to + ramoops.mem_address parameter used by kernel + +config CMD_PSTORE_SIZE + hex "Mem size" + depends on CMD_PSTORE + default "0x0" + help + Size of PStore ramoops memory, should be identical to ramoops.mem_size + parameter used by kernel + +config CMD_PSTORE_RECORD_SIZE + hex "Dump record size" + depends on CMD_PSTORE + default "0x1000" + help + Size of each dump done on oops/panic, should be identical to + ramoops.record_size parameter used by kernel + +config CMD_PSTORE_CONSOLE_SIZE + hex "Kernel console log size" + depends on CMD_PSTORE + default "0x1000" + help + Size of kernel console log, should be identical to + ramoops.console_size parameter used by kernel + +config CMD_PSTORE_FTRACE_SIZE + hex "FTrace log size" + depends on CMD_PSTORE + default "0x1000" + help + Size of ftrace log, should be identical to ramoops.ftrace_size + parameter used by kernel + +config CMD_PSTORE_PMSG_SIZE + hex "User space message log size" + depends on CMD_PSTORE + default "0x1000" + help + Size of user space message log, should be identical to + ramoops.pmsg_size parameter used by kernel + +config CMD_PSTORE_ECC_SIZE + int "ECC size" + depends on CMD_PSTORE + default "0" + help + if non-zero, the option enables ECC support and specifies ECC buffer + size in bytes (1 is a special value, means 16 bytes ECC), should be + identical to ramoops.ramoops_ecc parameter used by kernel + source "cmd/mvebu/Kconfig"
config CMD_TERMINAL diff --git a/cmd/Makefile b/cmd/Makefile index 2d723ea0f0..0f3196b3d6 100644 --- a/cmd/Makefile +++ b/cmd/Makefile @@ -108,6 +108,7 @@ ifdef CONFIG_PCI obj-$(CONFIG_CMD_PCI) += pci.o endif obj-$(CONFIG_CMD_PINMUX) += pinmux.o +obj-$(CONFIG_CMD_PSTORE) += pstore.o obj-$(CONFIG_CMD_PXE) += pxe.o obj-$(CONFIG_CMD_WOL) += wol.o obj-$(CONFIG_CMD_QFW) += qfw.o diff --git a/cmd/pstore.c b/cmd/pstore.c new file mode 100644 index 0000000000..60266a3027 --- /dev/null +++ b/cmd/pstore.c @@ -0,0 +1,417 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright © 2019 Collabora Ltd + * + */ + +#include <config.h> +#include <common.h> +#include <fs.h> +#include <memalign.h> +#include <part.h> +#include <asm/atomic.h> + +struct persistent_ram_buffer { + u32 sig; + u32 start; + u32 size; + u8 data[0]; +}; + +#define PERSISTENT_RAM_SIG (0x43474244) /* DBGC */ +#define RAMOOPS_KERNMSG_HDR "====" + +#define PSTORE_TYPE_DMESG 0 +#define PSTORE_TYPE_CONSOLE 2 +#define PSTORE_TYPE_FTRACE 3 +#define PSTORE_TYPE_PMSG 7 +#define PSTORE_TYPE_ALL 255 + +static char *pstore_addr = (char *)CONFIG_CMD_PSTORE_ADDR; +static ulong pstore_length = CONFIG_CMD_PSTORE_SIZE; +static unsigned int pstore_record_size = CONFIG_CMD_PSTORE_RECORD_SIZE; +static unsigned int pstore_console_size = CONFIG_CMD_PSTORE_CONSOLE_SIZE; +static unsigned int pstore_ftrace_size = CONFIG_CMD_PSTORE_FTRACE_SIZE; +static unsigned int pstore_pmsg_size = CONFIG_CMD_PSTORE_PMSG_SIZE; +static unsigned int pstore_ecc_size = CONFIG_CMD_PSTORE_ECC_SIZE; +static unsigned int buffer_size; + +/* Check kernel header and get compression flag if available. + * Kernel header: ====<secs>.<nsecs>[-<compression>]\n + * compression: C if record is compressed, else D + * Returns length of kernel header. + */ +static int pstore_read_kmsg_hdr(char *buffer, bool *compressed) +{ + char *ptr = buffer; + *compressed = false; + + if (strncmp(RAMOOPS_KERNMSG_HDR, ptr, strlen(RAMOOPS_KERNMSG_HDR)) != 0) + return 0; + + ptr += strlen(RAMOOPS_KERNMSG_HDR); + + ptr = strchr(ptr, '\n'); + if (!ptr) + return 0; + + if (ptr[-2] == '-' && ptr[-1] == 'C') + *compressed = true; + + return ptr - buffer + 1; +} + +/* Get unwrapped record buffer + * Record header: <signature><start><size> + * signature is 'DBGC' for all records except for Ftrace's record(s) wich use + * LINUX_VERSION_CODE ^ 'DBGC', use 0 to prevent checking signature + * start and size are 4 bytes long + * Returns record's length + */ +static u32 pstore_get_buffer(u32 sig, char *buffer, u32 size, char *dest) +{ + struct persistent_ram_buffer *prb = (struct persistent_ram_buffer *)buffer; + + if (sig == 0 || prb->sig == sig) { + if (prb->size == 0) { + pr_debug("found existing empty buffer\n"); + return 0; + } + + if (prb->size > size || prb->start > prb->size) { + pr_debug("found existing invalid buffer, size %zu, start %zu\n", + prb->size, prb->start); + return 0; + } + } else { + pr_debug("no valid data in buffer (sig = 0x%08x)\n", prb->sig); + return 0; + } + + pr_debug("found existing buffer, size %zu, start %zu\n", + prb->size, prb->start); + + memcpy(dest, &prb->data[prb->start], prb->size - prb->start); + memcpy(dest + prb->size - prb->start, &prb->data[0], prb->start); + + return prb->size; +} + +static void pstore_init_buffer_size(void) +{ + if (pstore_record_size > buffer_size) + buffer_size = pstore_record_size; + + if (pstore_console_size > buffer_size) + buffer_size = pstore_console_size; + + if (pstore_ftrace_size > buffer_size) + buffer_size = pstore_ftrace_size; + + if (pstore_pmsg_size > buffer_size) + buffer_size = pstore_pmsg_size; +} + +static int pstore_set(cmd_tbl_t *cmdtp, int flag, int argc, + char * const argv[]) +{ + if (argc < 3) + return CMD_RET_USAGE; + + /* Address is specified since argc > 2 + */ + pstore_addr = (char *)simple_strtoul(argv[1], NULL, 16); + + /* Length is specified since argc > 2 + */ + pstore_length = simple_strtoul(argv[2], NULL, 16); + + if (argc > 3) + pstore_record_size = simple_strtoul(argv[3], NULL, 16); + + if (argc > 4) + pstore_console_size = simple_strtoul(argv[4], NULL, 16); + + if (argc > 5) + pstore_ftrace_size = simple_strtoul(argv[5], NULL, 16); + + if (argc > 6) + pstore_pmsg_size = simple_strtoul(argv[6], NULL, 16); + + if (argc > 7) + pstore_ecc_size = simple_strtoul(argv[7], NULL, 16); + + if (pstore_length < (pstore_record_size + pstore_console_size + + pstore_ftrace_size + pstore_pmsg_size)) { + printf("pstore <len> should be larger than the sum of all records sizes\n"); + pstore_length = 0; + } + + pr_debug("pstore set done: start 0x%p - length 0x%lX\n", pstore_addr, + pstore_length); + + return 0; +} + +static void pstore_print_buffer(char *type, char *buffer, u32 size) +{ + u32 i = 0; + + printf("**** %s\n", type); + while (i < size && buffer[i] != 0) { + putc(buffer[i]); + i++; + } +} + +static int pstore_display(cmd_tbl_t *cmdtp, int flag, int argc, + char * const argv[]) +{ + int type = PSTORE_TYPE_ALL; + char *ptr; + char *buffer; + u32 size; + int header_len = 0; + bool compressed; + + if (argc > 1) { + if (!strcmp(argv[1], "dump")) + type = PSTORE_TYPE_DMESG; + else if (!strcmp(argv[1], "console")) + type = PSTORE_TYPE_CONSOLE; + else if (!strcmp(argv[1], "ftrace")) + type = PSTORE_TYPE_FTRACE; + else if (!strcmp(argv[1], "user")) + type = PSTORE_TYPE_PMSG; + else + return CMD_RET_USAGE; + } + + if (pstore_length == 0) { + printf("Please set PStore configuration\n"); + return CMD_RET_USAGE; + } + + if (buffer_size == 0) + pstore_init_buffer_size(); + + buffer = malloc_cache_aligned(buffer_size); + + if (type == PSTORE_TYPE_DMESG || type == PSTORE_TYPE_ALL) { + ptr = pstore_addr; + char *ptr_end = ptr + pstore_length - pstore_pmsg_size + - pstore_ftrace_size - pstore_console_size; + + if (argc > 2) { + ptr += simple_strtoul(argv[2], NULL, 10) + * pstore_record_size; + ptr_end = ptr + pstore_record_size; + } + + while (ptr < ptr_end) { + size = pstore_get_buffer(PERSISTENT_RAM_SIG, ptr, + pstore_record_size, buffer); + ptr += pstore_record_size; + + if (size == 0) + continue; + + header_len = pstore_read_kmsg_hdr(buffer, &compressed); + if (header_len == 0) { + pr_debug("no valid kernel header\n"); + continue; + } + + if (compressed) { + printf("Compressed buffer, display not available\n"); + continue; + } + + pstore_print_buffer("Dump", buffer + header_len, + size - header_len); + } + } + + if (type == PSTORE_TYPE_CONSOLE || type == PSTORE_TYPE_ALL) { + ptr = pstore_addr + pstore_length - pstore_pmsg_size + - pstore_ftrace_size - pstore_console_size; + size = pstore_get_buffer(PERSISTENT_RAM_SIG, ptr, + pstore_console_size, buffer); + if (size != 0) + pstore_print_buffer("Console", buffer, size); + } + + if (type == PSTORE_TYPE_FTRACE || type == PSTORE_TYPE_ALL) { + ptr = pstore_addr + pstore_length - pstore_pmsg_size + - pstore_ftrace_size; + /* The FTrace record(s) uses LINUX_VERSION_CODE ^ 'DBGC' + * signature, pass 0 to pstore_get_buffer to prevent + * checking it + */ + size = pstore_get_buffer(0, ptr, pstore_ftrace_size, buffer); + if (size != 0) + pstore_print_buffer("FTrace", buffer, size); + } + + if (type == PSTORE_TYPE_PMSG || type == PSTORE_TYPE_ALL) { + ptr = pstore_addr + pstore_length - pstore_pmsg_size; + size = pstore_get_buffer(PERSISTENT_RAM_SIG, ptr, + pstore_pmsg_size, buffer); + if (size != 0) + pstore_print_buffer("User", buffer, size); + } + + free(buffer); + + return 0; +} + +static int pstore_save(cmd_tbl_t *cmdtp, int flag, int argc, + char * const argv[]) +{ + char *ptr, *ptr_end; + char *buffer; + char *save_argv[6]; + char addr[11], length[11]; + char path[256]; + u32 size; + unsigned int index; + int header_len = 0; + bool compressed; + + if (argc < 4) + return CMD_RET_USAGE; + + if (pstore_length == 0) { + printf("Please set PStore configuration\n"); + return CMD_RET_USAGE; + } + + if (buffer_size == 0) + pstore_init_buffer_size(); + + buffer = malloc_cache_aligned(buffer_size); + sprintf(addr, "0x%p", buffer); + + save_argv[0] = argv[0]; + save_argv[1] = argv[1]; + save_argv[2] = argv[2]; + save_argv[3] = addr; + save_argv[4] = path; + save_argv[5] = length; + + /* Save all Dump records */ + ptr = pstore_addr; + ptr_end = ptr + pstore_length - pstore_pmsg_size - pstore_ftrace_size + - pstore_console_size; + index = 0; + while (ptr < ptr_end) { + size = pstore_get_buffer(PERSISTENT_RAM_SIG, ptr, + pstore_record_size, buffer); + ptr += pstore_record_size; + + if (size == 0) + continue; + + header_len = pstore_read_kmsg_hdr(buffer, &compressed); + if (header_len == 0) { + pr_debug("no valid kernel header\n"); + continue; + } + + sprintf(addr, "0x%p", buffer + header_len); + sprintf(length, "0x%X", size - header_len); + sprintf(path, "%s/dmesg-ramoops-%u%s", argv[3], index, + compressed ? ".enc.z" : ""); + do_save(cmdtp, flag, 6, save_argv, FS_TYPE_ANY); + index++; + } + + sprintf(addr, "0x%p", buffer); + + /* Save Console record */ + size = pstore_get_buffer(PERSISTENT_RAM_SIG, ptr, pstore_console_size, + buffer); + if (size != 0) { + sprintf(length, "0x%X", size); + sprintf(path, "%s/console-ramoops-0", argv[3]); + do_save(cmdtp, flag, 6, save_argv, FS_TYPE_ANY); + } + ptr += pstore_console_size; + + /* Save FTrace record(s) + * The FTrace record(s) uses LINUX_VERSION_CODE ^ 'DBGC' signature, + * pass 0 to pstore_get_buffer to prevent checking it + */ + size = pstore_get_buffer(0, ptr, pstore_ftrace_size, buffer); + if (size != 0) { + sprintf(length, "0x%X", size); + sprintf(path, "%s/ftrace-ramoops-0", argv[3]); + do_save(cmdtp, flag, 6, save_argv, FS_TYPE_ANY); + } + ptr += pstore_ftrace_size; + + /* Save Console record */ + size = pstore_get_buffer(PERSISTENT_RAM_SIG, ptr, pstore_pmsg_size, + buffer); + if (size != 0) { + sprintf(length, "0x%X", size); + sprintf(path, "%s/pmsg-ramoops-0", argv[3]); + do_save(cmdtp, flag, 6, save_argv, FS_TYPE_ANY); + } + + free(buffer); + + return 0; +} + +static cmd_tbl_t cmd_pstore_sub[] = { + U_BOOT_CMD_MKENT(set, 8, 0, pstore_set, "", ""), + U_BOOT_CMD_MKENT(display, 3, 0, pstore_display, "", ""), + U_BOOT_CMD_MKENT(save, 4, 0, pstore_save, "", ""), +}; + +static int do_pstore(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) +{ + cmd_tbl_t *c; + + if (argc < 2) + return CMD_RET_USAGE; + + /* Strip off leading argument */ + argc--; + argv++; + + c = find_cmd_tbl(argv[0], &cmd_pstore_sub[0], + ARRAY_SIZE(cmd_pstore_sub)); + + if (!c) + return CMD_RET_USAGE; + + return c->cmd(cmdtp, flag, argc, argv); +} + +U_BOOT_CMD(pstore, 10, 0, do_pstore, + "Manage Linux Persistent Storage", + "set <addr> <len> [record-size] [console-size] [ftrace-size] [pmsg_size] [ecc-size]\n" + "- Set pstore reserved memory info, starting at 'addr' for 'len' bytes.\n" + " Default length for records is 4K.\n" + " 'record-size' is the size of one panic or oops record ('dump' type).\n" + " 'console-size' is the size of the kernel logs record.\n" + " 'ftrace-size' is the size of the ftrace record(s), depending on 'flags'\n" + " this can be a single record or divided in parts based on number of CPUs.\n" + " 'pmsg-size' is the size of the user space logs record.\n" + " 'ecc-size' enables/disables ECC support and specifies ECC buffer size in\n" + " bytes (0 disables it, 1 is a special value, means 16 bytes ECC).\n" + "pstore display [record-type] [nb]\n" + "- Display existing records in pstore reserved memory. A 'record-type' can\n" + " be given to only display records of this kind. 'record-type' can be one\n" + " of 'dump', 'console', 'ftrace' or 'user'. For 'dump' and 'ftrace' types,\n" + " a 'nb' can be given to only display one record.\n" + "pstore save <interface> <dev[:part]> <directory-path>\n" + "- Save existing records in pstore reserved memory under 'directory path'\n" + " to partition 'part' on device type 'interface' instance 'dev'.\n" + " Filenames are automatically generated, depending on record type, like\n" + " in /sys/fs/pstore under Linux.\n" + " The 'directory-path' should already exist.\n" +);