From: Aditya Gupta Date: Tue, 21 Oct 2025 13:48:11 +0000 (+0530) Subject: hw/ppc: Implement fadump register command X-Git-Tag: v10.2.0-rc1~48^2~7 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=a728c87e966d4d4ca1675fbe7127c813fb8f66e1;p=thirdparty%2Fqemu.git hw/ppc: Implement fadump register command Add skeleton to handle "ibm,configure-kernel-dump" rtas call in QEMU, including register, unregister and invalidate commands. The register just verifies the structure of the fadump memory structure passed by kernel, and set fadump_registered in spapr state to true. Verify basic details mandated by the PAPR, such as number of inputs/output, and add handling for the three fadump commands: regiser/unregister/invalidate. The checks are based on the table in following requirement in PAPR v2.13: "R1–7.3.30–1. For the Configure Platform Assisted Kernel Dump option ..." Relevant section for the register command in PAPR is: Section 7.3.30: "ibm,configure-kernel-dump RTAS call" (PAPR v2.13) Note: Any modifications made by the kernel to the fadump memory structure after the 'ibm,configure-kernel-dump' RTAS call returns will not be reflected in QEMU, as QEMU retains the fadump memory structure that was provided during fadump registration. The kernel must unregister and re-register fadump to apply any changes to the fadump memory structure. Signed-off-by: Aditya Gupta Reviewed-by: Sourabh Jain Tested-by: Shivang Upadhyay Link: https://lore.kernel.org/qemu-devel/20251021134823.1861675-2-adityag@linux.ibm.com Signed-off-by: Harsh Prateek Bora --- diff --git a/hw/ppc/meson.build b/hw/ppc/meson.build index 170b90ae7d..6b7c1f4f49 100644 --- a/hw/ppc/meson.build +++ b/hw/ppc/meson.build @@ -26,6 +26,7 @@ ppc_ss.add(when: 'CONFIG_PSERIES', if_true: files( 'spapr_nvdimm.c', 'spapr_rtas_ddw.c', 'spapr_numa.c', + 'spapr_fadump.c', 'pef.c', )) ppc_ss.add(when: ['CONFIG_PSERIES', 'CONFIG_TCG'], if_true: files( diff --git a/hw/ppc/spapr_fadump.c b/hw/ppc/spapr_fadump.c new file mode 100644 index 0000000000..2c9f024c2d --- /dev/null +++ b/hw/ppc/spapr_fadump.c @@ -0,0 +1,123 @@ +/* + * Firmware Assisted Dump in PSeries + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +#include "qemu/osdep.h" +#include "qemu/log.h" +#include "hw/ppc/spapr.h" + +/* + * Handle the "FADUMP_CMD_REGISTER" command in 'ibm,configure-kernel-dump' + * + * Note: Any changes made by the kernel to the fadump memory struct won't + * reflect in QEMU after the 'ibm,configure-kernel-dump' RTAS call has returned, + * as we store the passed fadump memory structure passed during fadump + * registration. + * Kernel has to invalidate & re-register fadump, if it intends to make any + * changes to the fadump memory structure + * + * Returns: + * * RTAS_OUT_SUCCESS: On successful registration + * * RTAS_OUT_PARAM_ERROR: If parameters are not correct, eg. too many + * sections, invalid memory addresses that we are + * unable to read, etc + * * RTAS_OUT_DUMP_ALREADY_REGISTERED: Dump already registered + * * RTAS_OUT_HW_ERROR: Misc issue such as memory access failures + */ +uint32_t do_fadump_register(SpaprMachineState *spapr, target_ulong args) +{ + FadumpSectionHeader header; + FadumpSection regions[FADUMP_MAX_SECTIONS] = {0}; + target_ulong fdm_addr = rtas_ld(args, 1); + target_ulong fdm_size = rtas_ld(args, 2); + AddressSpace *default_as = &address_space_memory; + MemTxResult io_result; + MemTxAttrs attrs; + uint64_t next_section_addr; + uint16_t dump_num_sections; + + /* Mark the memory transaction as privileged memory access */ + attrs.user = 0; + attrs.memory = 1; + + if (spapr->fadump_registered) { + /* FADump already registered */ + return RTAS_OUT_DUMP_ALREADY_REGISTERED; + } + + if (spapr->fadump_dump_active) { + return RTAS_OUT_DUMP_ACTIVE; + } + + if (fdm_size < sizeof(FadumpSectionHeader)) { + qemu_log_mask(LOG_GUEST_ERROR, + "FADump: Header size is invalid: " TARGET_FMT_lu "\n", fdm_size); + return RTAS_OUT_PARAM_ERROR; + } + + /* Ensure fdm_addr points to a valid RMR-memory/RMA-memory buffer */ + if ((fdm_addr <= 0) || ((fdm_addr + fdm_size) > spapr->rma_size)) { + qemu_log_mask(LOG_GUEST_ERROR, + "FADump: Invalid fdm address: " TARGET_FMT_lu "\n", fdm_addr); + return RTAS_OUT_PARAM_ERROR; + } + + /* Try to read the passed fadump header */ + io_result = address_space_read(default_as, fdm_addr, attrs, + &header, sizeof(header)); + if (io_result != MEMTX_OK) { + qemu_log_mask(LOG_GUEST_ERROR, + "FADump: Unable to read fdm: " TARGET_FMT_lu "\n", fdm_addr); + + return RTAS_OUT_HW_ERROR; + } + + /* Verify that we understand the fadump header version */ + if (header.dump_format_version != cpu_to_be32(FADUMP_VERSION)) { + qemu_log_mask(LOG_GUEST_ERROR, + "FADump: Unknown fadump header version: 0x%x\n", + header.dump_format_version); + return RTAS_OUT_PARAM_ERROR; + } + + /* Reset dump status flags */ + header.dump_status_flag = 0; + + dump_num_sections = be16_to_cpu(header.dump_num_sections); + + if (dump_num_sections > FADUMP_MAX_SECTIONS) { + qemu_log_mask(LOG_GUEST_ERROR, + "FADump: Too many sections: %d sections\n", dump_num_sections); + return RTAS_OUT_PARAM_ERROR; + } + + next_section_addr = + fdm_addr + + be32_to_cpu(header.offset_first_dump_section); + + for (int i = 0; i < dump_num_sections; ++i) { + /* Read the fadump section from memory */ + io_result = address_space_read(default_as, next_section_addr, attrs, + ®ions[i], sizeof(regions[i])); + if (io_result != MEMTX_OK) { + qemu_log_mask(LOG_UNIMP, + "FADump: Unable to read fadump %dth section\n", i); + return RTAS_OUT_PARAM_ERROR; + } + + next_section_addr += sizeof(regions[i]); + } + + spapr->fadump_registered = true; + spapr->fadump_dump_active = false; + + /* Store the registered fadump memory struct */ + spapr->registered_fdm.header = header; + for (int i = 0; i < dump_num_sections; ++i) { + spapr->registered_fdm.rgn[i] = regions[i]; + } + + return RTAS_OUT_SUCCESS; +} diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c index 143bc8c379..6042fc72e5 100644 --- a/hw/ppc/spapr_rtas.c +++ b/hw/ppc/spapr_rtas.c @@ -344,6 +344,73 @@ static void rtas_ibm_set_system_parameter(PowerPCCPU *cpu, rtas_st(rets, 0, ret); } +/* Papr Section 7.4.9 ibm,configure-kernel-dump RTAS call */ +static void rtas_configure_kernel_dump(PowerPCCPU *cpu, + SpaprMachineState *spapr, + uint32_t token, uint32_t nargs, + target_ulong args, + uint32_t nret, target_ulong rets) +{ + target_ulong cmd = rtas_ld(args, 0); + uint32_t ret_val; + + /* Number of outputs has to be 1 */ + if (nret != 1) { + qemu_log_mask(LOG_GUEST_ERROR, + "FADump: ibm,configure-kernel-dump called with nret != 1.\n"); + rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR); + return; + } + + /* Number of inputs has to be 3 */ + if (nargs != 3) { + qemu_log_mask(LOG_GUEST_ERROR, + "FADump: ibm,configure-kernel-dump called with nargs != 3.\n"); + rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR); + return; + } + + switch (cmd) { + case FADUMP_CMD_REGISTER: + ret_val = do_fadump_register(spapr, args); + if (ret_val != RTAS_OUT_SUCCESS) { + rtas_st(rets, 0, ret_val); + return; + } + break; + case FADUMP_CMD_UNREGISTER: + if (spapr->fadump_dump_active) { + rtas_st(rets, 0, RTAS_OUT_DUMP_ACTIVE); + return; + } + + spapr->fadump_registered = false; + spapr->fadump_dump_active = false; + memset(&spapr->registered_fdm, 0, sizeof(spapr->registered_fdm)); + break; + case FADUMP_CMD_INVALIDATE: + if (!spapr->fadump_dump_active) { + qemu_log_mask(LOG_GUEST_ERROR, + "FADump: Nothing to invalidate, no dump active\n"); + + rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR); + } + + spapr->fadump_registered = false; + spapr->fadump_dump_active = false; + memset(&spapr->registered_fdm, 0, sizeof(spapr->registered_fdm)); + break; + default: + qemu_log_mask(LOG_GUEST_ERROR, + "FADump: Unknown command: " TARGET_FMT_lu "\n", cmd); + + rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR); + return; + } + + rtas_st(rets, 0, RTAS_OUT_SUCCESS); +} + static void rtas_ibm_os_term(PowerPCCPU *cpu, SpaprMachineState *spapr, uint32_t token, uint32_t nargs, @@ -659,6 +726,10 @@ static void core_rtas_register_types(void) spapr_rtas_register(RTAS_IBM_NMI_INTERLOCK, "ibm,nmi-interlock", rtas_ibm_nmi_interlock); + /* Register fadump rtas call */ + spapr_rtas_register(RTAS_CONFIGURE_KERNEL_DUMP, "ibm,configure-kernel-dump", + rtas_configure_kernel_dump); + qtest_set_command_cb(spapr_qtest_callback); } diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h index b9d884745f..28cf2723d8 100644 --- a/include/hw/ppc/spapr.h +++ b/include/hw/ppc/spapr.h @@ -13,6 +13,7 @@ #include "hw/ppc/xics.h" /* For ICSState */ #include "hw/ppc/spapr_tpm_proxy.h" #include "hw/ppc/spapr_nested.h" /* For SpaprMachineStateNested */ +#include "hw/ppc/spapr_fadump.h" /* For FadumpMemStruct */ struct SpaprVioBus; struct SpaprPhbState; @@ -267,6 +268,11 @@ struct SpaprMachineState { Error *fwnmi_migration_blocker; SpaprWatchdog wds[WDT_MAX_WATCHDOGS]; + + /* Fadump State */ + bool fadump_registered; + bool fadump_dump_active; + FadumpMemStruct registered_fdm; }; #define H_SUCCESS 0 @@ -692,6 +698,8 @@ void push_sregs_to_kvm_pr(SpaprMachineState *spapr); #define RTAS_OUT_PARAM_ERROR -3 #define RTAS_OUT_NOT_SUPPORTED -3 #define RTAS_OUT_NO_SUCH_INDICATOR -3 +#define RTAS_OUT_DUMP_ALREADY_REGISTERED -9 +#define RTAS_OUT_DUMP_ACTIVE -10 #define RTAS_OUT_NOT_AUTHORIZED -9002 #define RTAS_OUT_SYSPARM_PARAM_ERROR -9999 @@ -754,8 +762,9 @@ void push_sregs_to_kvm_pr(SpaprMachineState *spapr); #define RTAS_IBM_SUSPEND_ME (RTAS_TOKEN_BASE + 0x2A) #define RTAS_IBM_NMI_REGISTER (RTAS_TOKEN_BASE + 0x2B) #define RTAS_IBM_NMI_INTERLOCK (RTAS_TOKEN_BASE + 0x2C) +#define RTAS_CONFIGURE_KERNEL_DUMP (RTAS_TOKEN_BASE + 0x2D) -#define RTAS_TOKEN_MAX (RTAS_TOKEN_BASE + 0x2D) +#define RTAS_TOKEN_MAX (RTAS_TOKEN_BASE + 0x2E) /* RTAS ibm,get-system-parameter token values */ #define RTAS_SYSPARM_SPLPAR_CHARACTERISTICS 20 diff --git a/include/hw/ppc/spapr_fadump.h b/include/hw/ppc/spapr_fadump.h new file mode 100644 index 0000000000..f64f339204 --- /dev/null +++ b/include/hw/ppc/spapr_fadump.h @@ -0,0 +1,69 @@ +/* + * Firmware Assisted Dump in PSeries + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ +#ifndef PPC_SPAPR_FADUMP_H +#define PPC_SPAPR_FADUMP_H + +#include "qemu/osdep.h" +#include "cpu.h" + +/* Fadump commands */ +#define FADUMP_CMD_REGISTER 1 +#define FADUMP_CMD_UNREGISTER 2 +#define FADUMP_CMD_INVALIDATE 3 + +#define FADUMP_VERSION 1 + +/* + * The Firmware Assisted Dump Memory structure supports a maximum of 10 sections + * in the dump memory structure. Presently, three sections are used for + * CPU state data, HPTE & Parameters area, while the remaining seven sections + * can be used for boot memory regions. + */ +#define FADUMP_MAX_SECTIONS 10 + +typedef struct FadumpSection FadumpSection; +typedef struct FadumpSectionHeader FadumpSectionHeader; +typedef struct FadumpMemStruct FadumpMemStruct; + +struct SpaprMachineState; + +/* Kernel Dump section info */ +/* All fields are in big-endian */ +struct FadumpSection { + uint32_t request_flag; + uint16_t source_data_type; + uint16_t error_flags; + uint64_t source_address; + uint64_t source_len; + uint64_t bytes_dumped; + uint64_t destination_address; +}; + +/* ibm,configure-kernel-dump header. */ +struct FadumpSectionHeader { + uint32_t dump_format_version; + uint16_t dump_num_sections; + uint16_t dump_status_flag; + uint32_t offset_first_dump_section; + + /* Fields for disk dump option. */ + uint32_t dd_block_size; + uint64_t dd_block_offset; + uint64_t dd_num_blocks; + uint32_t dd_offset_disk_path; + + /* Maximum time allowed to prevent an automatic dump-reboot. */ + uint32_t max_time_auto; +}; + +/* Note: All the data in these structures is in big-endian */ +struct FadumpMemStruct { + FadumpSectionHeader header; + FadumpSection rgn[FADUMP_MAX_SECTIONS]; +}; + +uint32_t do_fadump_register(struct SpaprMachineState *, target_ulong); +#endif /* PPC_SPAPR_FADUMP_H */