Implement the register command of "ibm,configure-kernel-dump" RTAS call. The register just verifies the structure of the fadump memory structure passed by kernel, and set fadump_registered in spapr state to true.
We also store the passed fadump memory structure, which will later be used for preserving memory for fadump boot in case of a crash. The fadump memory structure isn't modified (other than .dump_status_flag after the fadump is triggered, that is in a later patch). So if the structure needs to updated, the kernel should first de-register and re-register the structure again. Relevant section for the register command in PAPR is: Section 7.3.30: "ibm,configure-kernel-dump RTAS call" (PAPR v2.13) Note: The fadump registration is done, but triggering fadump on an os-term rtas call is done in later patches. Hence QEMU will just shutdown on a kernel crash due to no special handling for fadump in ibm,os-term Signed-off-by: Aditya Gupta <adit...@linux.ibm.com> --- hw/ppc/spapr_fadump.c | 111 ++++++++++++++++++++++++++++++++-- hw/ppc/spapr_rtas.c | 2 +- include/hw/ppc/spapr_fadump.h | 2 +- 3 files changed, 108 insertions(+), 7 deletions(-) diff --git a/hw/ppc/spapr_fadump.c b/hw/ppc/spapr_fadump.c index 20b7b804c485..9c7fb9e12b16 100644 --- a/hw/ppc/spapr_fadump.c +++ b/hw/ppc/spapr_fadump.c @@ -5,18 +5,119 @@ */ #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_HW_ERROR: Not implemented/Misc issue such as memory access - * failures + * * 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(void) +uint32_t do_fadump_register(SpaprMachineState *spapr, target_ulong args) { - /* WIP: FADUMP_CMD_REGISTER implemented in future patch */ + 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 == 1) { + return RTAS_OUT_DUMP_ACTIVE; + } + + if (fdm_size < sizeof(FadumpSectionHeader)) { + qemu_log_mask(LOG_GUEST_ERROR, + "FADump: Header size is invalid: %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: %ld\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 address: %ld\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_HW_ERROR; + return RTAS_OUT_SUCCESS; } diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c index b8bfa9c33fb5..0454938a01e9 100644 --- a/hw/ppc/spapr_rtas.c +++ b/hw/ppc/spapr_rtas.c @@ -366,7 +366,7 @@ static void rtas_configure_kernel_dump(PowerPCCPU *cpu, switch (cmd) { case FADUMP_CMD_REGISTER: - ret_val = do_fadump_register(); + ret_val = do_fadump_register(spapr, args); if (ret_val != RTAS_OUT_SUCCESS) { rtas_st(rets, 0, ret_val); return; diff --git a/include/hw/ppc/spapr_fadump.h b/include/hw/ppc/spapr_fadump.h index 45109fd9e137..6abbcb44f353 100644 --- a/include/hw/ppc/spapr_fadump.h +++ b/include/hw/ppc/spapr_fadump.h @@ -65,5 +65,5 @@ struct FadumpMemStruct { FadumpSection rgn[FADUMP_MAX_SECTIONS]; }; -uint32_t do_fadump_register(void); +uint32_t do_fadump_register(struct SpaprMachineState *, target_ulong); #endif /* PPC_SPAPR_FADUMP_H */ -- 2.48.1