@@ -904,6 +904,9 @@ static void spapr_dt_rtas_fadump(SpaprMachineState *spapr, void *fdt, int rtas)
{
MachineState *ms = MACHINE(spapr);
MachineClass *mc = MACHINE_GET_CLASS(ms);
+ FadumpMemStruct *fdm = &spapr->registered_fdm;
+ uint16_t dump_status_flag;
+ bool is_next_boot_fadump;
uint32_t max_possible_cpus = mc->possible_cpu_arch_ids(ms)->len;
uint64_t fadump_cpu_state_size = 0;
@@ -953,6 +956,18 @@ static void spapr_dt_rtas_fadump(SpaprMachineState *spapr, void *fdt, int rtas)
fadump_versions, sizeof(fadump_versions))));
_FDT((fdt_setprop(fdt, rtas, "ibm,configure-kernel-dump-sizes",
fadump_rgn_sizes, sizeof(fadump_rgn_sizes))));
+
+ dump_status_flag = be16_to_cpu(fdm->header.dump_status_flag);
+ is_next_boot_fadump =
+ (dump_status_flag & FADUMP_STATUS_DUMP_TRIGGERED) != 0;
+ if (is_next_boot_fadump) {
+ uint64_t fdm_size =
+ sizeof(struct FadumpSectionHeader) +
+ (be16_to_cpu(fdm->header.dump_num_sections) *
+ sizeof(struct FadumpSection));
+
+ _FDT((fdt_setprop(fdt, rtas, "ibm,kernel-dump", fdm, fdm_size)));
+ }
}
static void spapr_dt_rtas(SpaprMachineState *spapr, void *fdt)
With all support in place for preserving memory regions, enable fadump by exporting the "ibm,kernel-dump" property in the device tree, representing the fadump dump information, in case of a crash. Currently "ibm,configure-kernel-dump" RTAS call is already registered, which tells the kernel that the platform (QEMU) supports fadump. Now, in case of a crash, if fadump was registered, we also pass "ibm,kernel-dump" in device tree, which tells the kernel that the fadump dump is active. Pass "fadump=on" to enable Linux to use firmware assisted dump. Logs of a linux boot with firmware assisted dump: $ ./build/qemu-system-ppc64 -M pseries,x-vof=on --cpu power10 --smp 4 -m 4G -kernel some-vmlinux -initrd some-initrd -append "debug fadump=on crashkernel=1G" -nographic [ 0.000000] fadump: Reserved 1024MB of memory at 0x00000040000000 (System RAM: 4096MB) [ 0.000000] fadump: Initialized 0x40000000 bytes cma area at 1024MB from 0x400102a8 bytes of memory reserved for firmware-assisted dump ... [ 1.084686] rtas fadump: Registration is successful! ... # cat /sys/kernel/debug/powerpc/fadump_region CPU :[0x00000040000000-0x000000400013df] 0x13e0 bytes, Dumped: 0x0 HPTE:[0x000000400013e0-0x000000400013df] 0x0 bytes, Dumped: 0x0 DUMP: Src: 0x00000000000000, Dest: 0x00000040010000, Size: 0x40000000, Dumped: 0x0 bytes [0x0000000921a000-0x0000000921a7ff]: cmdline append: '' # echo c > /proc/sysrq-trigger The fadump boot after crash: [ 0.000000] rtas fadump: Firmware-assisted dump is active. [ 0.000000] fadump: Updated cmdline: debug fadump=on crashkernel=1G [ 0.000000] fadump: Firmware-assisted dump is active. [ 0.000000] fadump: Reserving 3072MB of memory at 0x00000040000000 for preserving crash data .... # file /proc/vmcore /proc/vmcore: ELF 64-bit LSB core file, 64-bit PowerPC or cisco 7500, OpenPOWER ELF V2 ABI, version 1 (SYSV), SVR4-style Analysing the vmcore with crash-utility: KERNEL: vmlinux-6.14-rc2 DUMPFILE: vmcore-fc92fb373aa0 CPUS: 4 DATE: Wed Mar 12 23:39:23 CDT 2025 UPTIME: 00:00:22 LOAD AVERAGE: 0.13, 0.03, 0.01 TASKS: 95 NODENAME: buildroot RELEASE: 6.12.0-rc4+ VERSION: #1 SMP Fri Jan 3 00:15:17 IST 2025 MACHINE: ppc64le (1000 Mhz) MEMORY: 4 GB PANIC: "Kernel panic - not syncing: sysrq triggered crash" PID: 269 COMMAND: "sh" TASK: c00000000a050b00 [THREAD_INFO: c00000000a050b00] CPU: 0 STATE: TASK_RUNNING (PANIC) Signed-off-by: Aditya Gupta <adityag@linux.ibm.com> --- hw/ppc/spapr.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+)