| Message ID | 156630276507.8896.7987455476577127053.stgit@hbathini.in.ibm.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Add FADump support on PowerNV platform | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/apply_patch | success | Successfully applied on branch next (c9633332103e55bc73d80d07ead28b95a22a85a3) |
| snowpatch_ozlabs/checkpatch | warning | total: 0 errors, 0 warnings, 5 checks, 216 lines checked |
Hari Bathini <hbathini@linux.ibm.com> writes: > diff --git a/arch/powerpc/platforms/powernv/opal-fadump.c b/arch/powerpc/platforms/powernv/opal-fadump.c > index a755705..10f6086 100644 > --- a/arch/powerpc/platforms/powernv/opal-fadump.c > +++ b/arch/powerpc/platforms/powernv/opal-fadump.c > @@ -41,6 +43,37 @@ static void opal_fadump_update_config(struct fw_dump *fadump_conf, > fadump_conf->fadumphdr_addr = fdm->fadumphdr_addr; > } > > +/* > + * This function is called in the capture kernel to get configuration details > + * from metadata setup by the first kernel. > + */ > +static void opal_fadump_get_config(struct fw_dump *fadump_conf, > + const struct opal_fadump_mem_struct *fdm) > +{ > + int i; > + > + if (!fadump_conf->dump_active) > + return; > + > + fadump_conf->boot_memory_size = 0; > + > + pr_debug("Boot memory regions:\n"); > + for (i = 0; i < fdm->region_cnt; i++) { > + pr_debug("\t%d. base: 0x%llx, size: 0x%llx\n", > + (i + 1), fdm->rgn[i].src, fdm->rgn[i].size); Printing the zero-based array off by one (i + 1) seems confusing. > + > + fadump_conf->boot_memory_size += fdm->rgn[i].size; > + } > + > + /* > + * Start address of reserve dump area (permanent reservation) for > + * re-registering FADump after dump capture. > + */ > + fadump_conf->reserve_dump_area_start = fdm->rgn[0].dest; > + > + opal_fadump_update_config(fadump_conf, fdm); > +} > + > /* Initialize kernel metadata */ > static void opal_fadump_init_metadata(struct opal_fadump_mem_struct *fdm) > { > @@ -215,24 +248,114 @@ static void opal_fadump_cleanup(struct fw_dump *fadump_conf) > pr_warn("Could not reset (%llu) kernel metadata tag!\n", ret); > } > > +/* > + * Convert CPU state data saved at the time of crash into ELF notes. > + */ > +static int __init opal_fadump_build_cpu_notes(struct fw_dump *fadump_conf) > +{ > + u32 num_cpus, *note_buf; > + struct fadump_crash_info_header *fdh = NULL; > + > + num_cpus = 1; > + /* Allocate buffer to hold cpu crash notes. */ > + fadump_conf->cpu_notes_buf_size = num_cpus * sizeof(note_buf_t); > + fadump_conf->cpu_notes_buf_size = > + PAGE_ALIGN(fadump_conf->cpu_notes_buf_size); > + note_buf = fadump_cpu_notes_buf_alloc(fadump_conf->cpu_notes_buf_size); > + if (!note_buf) { > + pr_err("Failed to allocate 0x%lx bytes for cpu notes buffer\n", > + fadump_conf->cpu_notes_buf_size); > + return -ENOMEM; > + } > + fadump_conf->cpu_notes_buf = __pa(note_buf); > + > + pr_debug("Allocated buffer for cpu notes of size %ld at %p\n", > + (num_cpus * sizeof(note_buf_t)), note_buf); > + > + if (fadump_conf->fadumphdr_addr) > + fdh = __va(fadump_conf->fadumphdr_addr); > + > + if (fdh && (fdh->crashing_cpu != FADUMP_CPU_UNKNOWN)) { > + note_buf = fadump_regs_to_elf_notes(note_buf, &(fdh->regs)); > + final_note(note_buf); > + > + pr_debug("Updating elfcore header (%llx) with cpu notes\n", > + fdh->elfcorehdr_addr); > + fadump_update_elfcore_header(fadump_conf, > + __va(fdh->elfcorehdr_addr)); > + } > + > + return 0; > +} > + > static int __init opal_fadump_process(struct fw_dump *fadump_conf) > { > - return -EINVAL; > + struct fadump_crash_info_header *fdh; > + int rc = 0; No need to initialise rc there. > + if (!opal_fdm_active || !fadump_conf->fadumphdr_addr) > + return -EINVAL; > + > + /* Validate the fadump crash info header */ > + fdh = __va(fadump_conf->fadumphdr_addr); > + if (fdh->magic_number != FADUMP_CRASH_INFO_MAGIC) { > + pr_err("Crash info header is not valid.\n"); > + return -EINVAL; > + } > + > + /* > + * TODO: To build cpu notes, find a way to map PIR to logical id. > + * Also, we may need different method for pseries and powernv. > + * The currently booted kernel could have a different PIR to > + * logical id mapping. So, try saving info of previous kernel's > + * paca to get the right PIR to logical id mapping. > + */ That TODO is removed by the end of the series, so please just omit it entirely. > + rc = opal_fadump_build_cpu_notes(fadump_conf); > + if (rc) > + return rc; I think this all runs early in boot, so we don't need to worry about another CPU seeing the partially initialised core due to there being no barrier here before we set elfcorehdr_addr? > + /* > + * We are done validating dump info and elfcore header is now ready > + * to be exported. set elfcorehdr_addr so that vmcore module will > + * export the elfcore header through '/proc/vmcore'. > + */ > + elfcorehdr_addr = fdh->elfcorehdr_addr; > @@ -283,5 +407,42 @@ int __init opal_fadump_dt_scan(struct fw_dump *fadump_conf, ulong node) > fadump_conf->ops = &opal_fadump_ops; > fadump_conf->fadump_supported = 1; > > + /* > + * Check if dump has been initiated on last reboot. > + */ > + prop = of_get_flat_dt_prop(dn, "mpipl-boot", NULL); > + if (prop) { if (!prop) return 1; And then everything below can be unindented. > + u64 addr = 0; > + s64 ret; > + const struct opal_fadump_mem_struct *r_opal_fdm_active; * / \ /_\ | > + > + ret = opal_mpipl_query_tag(OPAL_MPIPL_TAG_KERNEL, &addr); > + if ((ret != OPAL_SUCCESS) || !addr) { > + pr_err("Failed to get Kernel metadata (%lld)\n", ret); > + return 1; > + } > + > + addr = be64_to_cpu(addr); > + pr_debug("Kernel metadata addr: %llx\n", addr); > + > + opal_fdm_active = __va(addr); > + r_opal_fdm_active = (void *)addr; Why do we need the r_ version? We're called early in boot, so we are still in real mode, but that's fine the CPU will ignore the top bits of the virtual address for us. > + if (r_opal_fdm_active->version != OPAL_FADUMP_VERSION) { > + pr_err("FADump active but version (%u) unsupported!\n", > + r_opal_fdm_active->version); > + return 1; > + } > + > + /* Kernel regions not registered with f/w for MPIPL */ > + if (r_opal_fdm_active->registered_regions == 0) { > + opal_fdm_active = NULL; > + return 1; > + } > + > + pr_info("Firmware-assisted dump is active.\n"); > + fadump_conf->dump_active = 1; > + opal_fadump_get_config(fadump_conf, r_opal_fdm_active); > + } > + > return 1; > } cheers
On 04/09/19 5:12 PM, Michael Ellerman wrote: > Hari Bathini <hbathini@linux.ibm.com> writes: >> diff --git a/arch/powerpc/platforms/powernv/opal-fadump.c b/arch/powerpc/platforms/powernv/opal-fadump.c >> index a755705..10f6086 100644 >> --- a/arch/powerpc/platforms/powernv/opal-fadump.c >> +++ b/arch/powerpc/platforms/powernv/opal-fadump.c >> @@ -41,6 +43,37 @@ static void opal_fadump_update_config(struct fw_dump *fadump_conf, >> fadump_conf->fadumphdr_addr = fdm->fadumphdr_addr; >> } >> >> +/* >> + * This function is called in the capture kernel to get configuration details >> + * from metadata setup by the first kernel. >> + */ >> +static void opal_fadump_get_config(struct fw_dump *fadump_conf, >> + const struct opal_fadump_mem_struct *fdm) >> +{ >> + int i; >> + >> + if (!fadump_conf->dump_active) >> + return; >> + >> + fadump_conf->boot_memory_size = 0; >> + >> + pr_debug("Boot memory regions:\n"); >> + for (i = 0; i < fdm->region_cnt; i++) { >> + pr_debug("\t%d. base: 0x%llx, size: 0x%llx\n", >> + (i + 1), fdm->rgn[i].src, fdm->rgn[i].size); > > Printing the zero-based array off by one (i + 1) seems confusing. Hmmm... Indexing the regions from `0` sounded inappropriate.. > >> + >> + fadump_conf->boot_memory_size += fdm->rgn[i].size; >> + } >> + >> + /* >> + * Start address of reserve dump area (permanent reservation) for >> + * re-registering FADump after dump capture. >> + */ >> + fadump_conf->reserve_dump_area_start = fdm->rgn[0].dest; >> + >> + opal_fadump_update_config(fadump_conf, fdm); >> +} >> + >> /* Initialize kernel metadata */ >> static void opal_fadump_init_metadata(struct opal_fadump_mem_struct *fdm) >> { >> @@ -215,24 +248,114 @@ static void opal_fadump_cleanup(struct fw_dump *fadump_conf) >> pr_warn("Could not reset (%llu) kernel metadata tag!\n", ret); >> } >> >> +/* >> + * Convert CPU state data saved at the time of crash into ELF notes. >> + */ >> +static int __init opal_fadump_build_cpu_notes(struct fw_dump *fadump_conf) >> +{ >> + u32 num_cpus, *note_buf; >> + struct fadump_crash_info_header *fdh = NULL; >> + >> + num_cpus = 1; >> + /* Allocate buffer to hold cpu crash notes. */ >> + fadump_conf->cpu_notes_buf_size = num_cpus * sizeof(note_buf_t); >> + fadump_conf->cpu_notes_buf_size = >> + PAGE_ALIGN(fadump_conf->cpu_notes_buf_size); >> + note_buf = fadump_cpu_notes_buf_alloc(fadump_conf->cpu_notes_buf_size); >> + if (!note_buf) { >> + pr_err("Failed to allocate 0x%lx bytes for cpu notes buffer\n", >> + fadump_conf->cpu_notes_buf_size); >> + return -ENOMEM; >> + } >> + fadump_conf->cpu_notes_buf = __pa(note_buf); >> + >> + pr_debug("Allocated buffer for cpu notes of size %ld at %p\n", >> + (num_cpus * sizeof(note_buf_t)), note_buf); >> + >> + if (fadump_conf->fadumphdr_addr) >> + fdh = __va(fadump_conf->fadumphdr_addr); >> + >> + if (fdh && (fdh->crashing_cpu != FADUMP_CPU_UNKNOWN)) { >> + note_buf = fadump_regs_to_elf_notes(note_buf, &(fdh->regs)); >> + final_note(note_buf); >> + >> + pr_debug("Updating elfcore header (%llx) with cpu notes\n", >> + fdh->elfcorehdr_addr); >> + fadump_update_elfcore_header(fadump_conf, >> + __va(fdh->elfcorehdr_addr)); >> + } >> + >> + return 0; >> +} >> + >> static int __init opal_fadump_process(struct fw_dump *fadump_conf) >> { >> - return -EINVAL; >> + struct fadump_crash_info_header *fdh; >> + int rc = 0; > > No need to initialise rc there. > rc = -EINVAL; and >> + if (!opal_fdm_active || !fadump_conf->fadumphdr_addr) >> + return -EINVAL; >> + >> + /* Validate the fadump crash info header */ >> + fdh = __va(fadump_conf->fadumphdr_addr); >> + if (fdh->magic_number != FADUMP_CRASH_INFO_MAGIC) { >> + pr_err("Crash info header is not valid.\n"); >> + return -EINVAL; return rc; ?? >> + } >> + >> + /* >> + * TODO: To build cpu notes, find a way to map PIR to logical id. >> + * Also, we may need different method for pseries and powernv. >> + * The currently booted kernel could have a different PIR to >> + * logical id mapping. So, try saving info of previous kernel's >> + * paca to get the right PIR to logical id mapping. >> + */ > > That TODO is removed by the end of the series, so please just omit it entirely. > >> + rc = opal_fadump_build_cpu_notes(fadump_conf); >> + if (rc) >> + return rc; > > I think this all runs early in boot, so we don't need to worry about > another CPU seeing the partially initialised core due to there being no > barrier here before we set elfcorehdr_addr? > This is processed in fs/proc/vmcore.c during fs_initcall() and the data within the core is processed much later (initrd). So, I think we are good here... >> + /* >> + * We are done validating dump info and elfcore header is now ready >> + * to be exported. set elfcorehdr_addr so that vmcore module will >> + * export the elfcore header through '/proc/vmcore'. >> + */ >> + elfcorehdr_addr = fdh->elfcorehdr_addr; > >> @@ -283,5 +407,42 @@ int __init opal_fadump_dt_scan(struct fw_dump *fadump_conf, ulong node) >> fadump_conf->ops = &opal_fadump_ops; >> fadump_conf->fadump_supported = 1; >> >> + /* >> + * Check if dump has been initiated on last reboot. >> + */ >> + prop = of_get_flat_dt_prop(dn, "mpipl-boot", NULL); >> + if (prop) { > > if (!prop) > return 1; > > And then everything below can be unindented. > >> + u64 addr = 0; >> + s64 ret; >> + const struct opal_fadump_mem_struct *r_opal_fdm_active; > > * > / \ > /_\ > | > :) Will take care of such instances... I think this should be added to checkpatch.pl >> + >> + ret = opal_mpipl_query_tag(OPAL_MPIPL_TAG_KERNEL, &addr); >> + if ((ret != OPAL_SUCCESS) || !addr) { >> + pr_err("Failed to get Kernel metadata (%lld)\n", ret); >> + return 1; >> + } >> + >> + addr = be64_to_cpu(addr); >> + pr_debug("Kernel metadata addr: %llx\n", addr); >> + >> + opal_fdm_active = __va(addr); >> + r_opal_fdm_active = (void *)addr; > > Why do we need the r_ version? > > We're called early in boot, so we are still in real mode, but that's > fine the CPU will ignore the top bits of the virtual address for us. I don't know if I am missing a trick here or if there is a bug somewhere but trying to access `opal_fdm_active->version` is not working for me.. - Hari
diff --git a/arch/powerpc/platforms/powernv/opal-fadump.c b/arch/powerpc/platforms/powernv/opal-fadump.c index a755705..10f6086 100644 --- a/arch/powerpc/platforms/powernv/opal-fadump.c +++ b/arch/powerpc/platforms/powernv/opal-fadump.c @@ -14,6 +14,7 @@ #include <linux/of_fdt.h> #include <linux/libfdt.h> #include <linux/mm.h> +#include <linux/crash_dump.h> #include <asm/page.h> #include <asm/opal.h> @@ -21,6 +22,7 @@ #include "../../kernel/fadump-common.h" #include "opal-fadump.h" +static const struct opal_fadump_mem_struct *opal_fdm_active; static struct opal_fadump_mem_struct *opal_fdm; static int opal_fadump_unregister(struct fw_dump *fadump_conf); @@ -41,6 +43,37 @@ static void opal_fadump_update_config(struct fw_dump *fadump_conf, fadump_conf->fadumphdr_addr = fdm->fadumphdr_addr; } +/* + * This function is called in the capture kernel to get configuration details + * from metadata setup by the first kernel. + */ +static void opal_fadump_get_config(struct fw_dump *fadump_conf, + const struct opal_fadump_mem_struct *fdm) +{ + int i; + + if (!fadump_conf->dump_active) + return; + + fadump_conf->boot_memory_size = 0; + + pr_debug("Boot memory regions:\n"); + for (i = 0; i < fdm->region_cnt; i++) { + pr_debug("\t%d. base: 0x%llx, size: 0x%llx\n", + (i + 1), fdm->rgn[i].src, fdm->rgn[i].size); + + fadump_conf->boot_memory_size += fdm->rgn[i].size; + } + + /* + * Start address of reserve dump area (permanent reservation) for + * re-registering FADump after dump capture. + */ + fadump_conf->reserve_dump_area_start = fdm->rgn[0].dest; + + opal_fadump_update_config(fadump_conf, fdm); +} + /* Initialize kernel metadata */ static void opal_fadump_init_metadata(struct opal_fadump_mem_struct *fdm) { @@ -215,24 +248,114 @@ static void opal_fadump_cleanup(struct fw_dump *fadump_conf) pr_warn("Could not reset (%llu) kernel metadata tag!\n", ret); } +/* + * Convert CPU state data saved at the time of crash into ELF notes. + */ +static int __init opal_fadump_build_cpu_notes(struct fw_dump *fadump_conf) +{ + u32 num_cpus, *note_buf; + struct fadump_crash_info_header *fdh = NULL; + + num_cpus = 1; + /* Allocate buffer to hold cpu crash notes. */ + fadump_conf->cpu_notes_buf_size = num_cpus * sizeof(note_buf_t); + fadump_conf->cpu_notes_buf_size = + PAGE_ALIGN(fadump_conf->cpu_notes_buf_size); + note_buf = fadump_cpu_notes_buf_alloc(fadump_conf->cpu_notes_buf_size); + if (!note_buf) { + pr_err("Failed to allocate 0x%lx bytes for cpu notes buffer\n", + fadump_conf->cpu_notes_buf_size); + return -ENOMEM; + } + fadump_conf->cpu_notes_buf = __pa(note_buf); + + pr_debug("Allocated buffer for cpu notes of size %ld at %p\n", + (num_cpus * sizeof(note_buf_t)), note_buf); + + if (fadump_conf->fadumphdr_addr) + fdh = __va(fadump_conf->fadumphdr_addr); + + if (fdh && (fdh->crashing_cpu != FADUMP_CPU_UNKNOWN)) { + note_buf = fadump_regs_to_elf_notes(note_buf, &(fdh->regs)); + final_note(note_buf); + + pr_debug("Updating elfcore header (%llx) with cpu notes\n", + fdh->elfcorehdr_addr); + fadump_update_elfcore_header(fadump_conf, + __va(fdh->elfcorehdr_addr)); + } + + return 0; +} + static int __init opal_fadump_process(struct fw_dump *fadump_conf) { - return -EINVAL; + struct fadump_crash_info_header *fdh; + int rc = 0; + + if (!opal_fdm_active || !fadump_conf->fadumphdr_addr) + return -EINVAL; + + /* Validate the fadump crash info header */ + fdh = __va(fadump_conf->fadumphdr_addr); + if (fdh->magic_number != FADUMP_CRASH_INFO_MAGIC) { + pr_err("Crash info header is not valid.\n"); + return -EINVAL; + } + + /* + * TODO: To build cpu notes, find a way to map PIR to logical id. + * Also, we may need different method for pseries and powernv. + * The currently booted kernel could have a different PIR to + * logical id mapping. So, try saving info of previous kernel's + * paca to get the right PIR to logical id mapping. + */ + rc = opal_fadump_build_cpu_notes(fadump_conf); + if (rc) + return rc; + + /* + * We are done validating dump info and elfcore header is now ready + * to be exported. set elfcorehdr_addr so that vmcore module will + * export the elfcore header through '/proc/vmcore'. + */ + elfcorehdr_addr = fdh->elfcorehdr_addr; + + return rc; } static void opal_fadump_region_show(struct fw_dump *fadump_conf, struct seq_file *m) { int i; - const struct opal_fadump_mem_struct *fdm_ptr = opal_fdm; + const struct opal_fadump_mem_struct *fdm_ptr; u64 dumped_bytes = 0; + if (fadump_conf->dump_active) + fdm_ptr = opal_fdm_active; + else + fdm_ptr = opal_fdm; + for (i = 0; i < fdm_ptr->region_cnt; i++) { + /* + * Only regions that are registered for MPIPL + * would have dump data. + */ + if ((fadump_conf->dump_active) && + (i < fdm_ptr->registered_regions)) + dumped_bytes = fdm_ptr->rgn[i].size; + seq_printf(m, "DUMP: Src: %#016llx, Dest: %#016llx, ", fdm_ptr->rgn[i].src, fdm_ptr->rgn[i].dest); seq_printf(m, "Size: %#llx, Dumped: %#llx bytes\n", fdm_ptr->rgn[i].size, dumped_bytes); } + + /* Dump is active. Show reserved area start address. */ + if (fadump_conf->dump_active) { + seq_printf(m, "\nMemory above %#016lx is reserved for saving crash dump\n", + fadump_conf->reserve_dump_area_start); + } } static void opal_fadump_trigger(struct fadump_crash_info_header *fdh, @@ -264,6 +387,7 @@ static struct fadump_ops opal_fadump_ops = { int __init opal_fadump_dt_scan(struct fw_dump *fadump_conf, ulong node) { unsigned long dn; + const __be32 *prop; /* * Check if Firmware-Assisted Dump is supported. if yes, check @@ -283,5 +407,42 @@ int __init opal_fadump_dt_scan(struct fw_dump *fadump_conf, ulong node) fadump_conf->ops = &opal_fadump_ops; fadump_conf->fadump_supported = 1; + /* + * Check if dump has been initiated on last reboot. + */ + prop = of_get_flat_dt_prop(dn, "mpipl-boot", NULL); + if (prop) { + u64 addr = 0; + s64 ret; + const struct opal_fadump_mem_struct *r_opal_fdm_active; + + ret = opal_mpipl_query_tag(OPAL_MPIPL_TAG_KERNEL, &addr); + if ((ret != OPAL_SUCCESS) || !addr) { + pr_err("Failed to get Kernel metadata (%lld)\n", ret); + return 1; + } + + addr = be64_to_cpu(addr); + pr_debug("Kernel metadata addr: %llx\n", addr); + + opal_fdm_active = __va(addr); + r_opal_fdm_active = (void *)addr; + if (r_opal_fdm_active->version != OPAL_FADUMP_VERSION) { + pr_err("FADump active but version (%u) unsupported!\n", + r_opal_fdm_active->version); + return 1; + } + + /* Kernel regions not registered with f/w for MPIPL */ + if (r_opal_fdm_active->registered_regions == 0) { + opal_fdm_active = NULL; + return 1; + } + + pr_info("Firmware-assisted dump is active.\n"); + fadump_conf->dump_active = 1; + opal_fadump_get_config(fadump_conf, r_opal_fdm_active); + } + return 1; }
Add support in the kernel to process the crash'ed kernel's memory preserved during MPIPL and export it as /proc/vmcore file for the userland scripts to filter and analyze it later. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> --- arch/powerpc/platforms/powernv/opal-fadump.c | 165 ++++++++++++++++++++++++++ 1 file changed, 163 insertions(+), 2 deletions(-)