OPAL loads kernel & initrd at 512MB offset (256MB size), also exported as ibm,opal/dump/fw-load-area. So, if boot memory size of FADump is less than 768MB, kernel memory to be exported as '/proc/vmcore' would be overwritten by f/w while loading kernel & initrd. To avoid such a scenario, enforce a minimum boot memory size of 768MB on OPAL platform.
Also, skip using FADump if a newer F/W version loads kernel & initrd above 768MB. Signed-off-by: Hari Bathini <hbath...@linux.ibm.com> --- arch/powerpc/kernel/fadump-common.h | 11 +--------- arch/powerpc/kernel/fadump.c | 11 +++++++++- arch/powerpc/platforms/powernv/opal-fadump.c | 29 ++++++++++++++++++++++++++ arch/powerpc/platforms/powernv/opal-fadump.h | 7 ++++++ arch/powerpc/platforms/pseries/rtas-fadump.c | 6 +++++ arch/powerpc/platforms/pseries/rtas-fadump.h | 11 ++++++++++ 6 files changed, 64 insertions(+), 11 deletions(-) diff --git a/arch/powerpc/kernel/fadump-common.h b/arch/powerpc/kernel/fadump-common.h index 5dbcefc..e758eb6 100644 --- a/arch/powerpc/kernel/fadump-common.h +++ b/arch/powerpc/kernel/fadump-common.h @@ -26,16 +26,6 @@ #define RMA_START 0x0 #define RMA_END (ppc64_rma_size) -/* - * On some Power systems where RMO is 128MB, it still requires minimum of - * 256MB for kernel to boot successfully. When kdump infrastructure is - * configured to save vmcore over network, we run into OOM issue while - * loading modules related to network setup. Hence we need additional 64M - * of memory to avoid OOM issue. - */ -#define MIN_BOOT_MEM (((RMA_END < (0x1UL << 28)) ? (0x1UL << 28) : RMA_END) \ - + (0x1UL << 26)) - /* The upper limit percentage for user specified boot memory size (25%) */ #define MAX_BOOT_MEM_RATIO 4 @@ -163,6 +153,7 @@ struct fadump_ops { ulong (*init_fadump_mem_struct)(struct fw_dump *fadump_config); ulong (*get_kernel_metadata_size)(void); int (*setup_kernel_metadata)(struct fw_dump *fadump_config); + ulong (*get_bootmem_min)(void); int (*register_fadump)(struct fw_dump *fadump_config); int (*unregister_fadump)(struct fw_dump *fadump_config); int (*invalidate_fadump)(struct fw_dump *fadump_config); diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c index bb6a63c..ffc9e3f 100644 --- a/arch/powerpc/kernel/fadump.c +++ b/arch/powerpc/kernel/fadump.c @@ -335,7 +335,8 @@ static inline unsigned long fadump_calculate_reserve_size(void) if (memory_limit && size > memory_limit) size = memory_limit; - return (size > MIN_BOOT_MEM ? size : MIN_BOOT_MEM); + return (size > fw_dump.ops->get_bootmem_min() ? size : + fw_dump.ops->get_bootmem_min()); } /* @@ -493,6 +494,14 @@ int __init fadump_reserve_mem(void) ALIGN(fw_dump.boot_memory_size, FADUMP_CMA_ALIGNMENT); #endif + + if (fw_dump.boot_memory_size < fw_dump.ops->get_bootmem_min()) { + pr_err("Can't enable fadump with boot memory size (0x%lx) less than 0x%lx\n", + fw_dump.boot_memory_size, + fw_dump.ops->get_bootmem_min()); + goto error_out; + } + if (!fadump_get_boot_mem_regions()) { pr_err("Too many holes in boot memory area to enable fadump\n"); goto error_out; diff --git a/arch/powerpc/platforms/powernv/opal-fadump.c b/arch/powerpc/platforms/powernv/opal-fadump.c index 3ef212d..618186e 100644 --- a/arch/powerpc/platforms/powernv/opal-fadump.c +++ b/arch/powerpc/platforms/powernv/opal-fadump.c @@ -15,6 +15,7 @@ #include <linux/string.h> #include <linux/seq_file.h> +#include <linux/of.h> #include <linux/of_fdt.h> #include <linux/libfdt.h> #include <linux/mm.h> @@ -241,6 +242,11 @@ static int opal_fadump_setup_kernel_metadata(struct fw_dump *fadump_conf) return err; } +static ulong opal_fadump_get_bootmem_min(void) +{ + return OPAL_FADUMP_MIN_BOOT_MEM; +} + static int opal_fadump_register_fadump(struct fw_dump *fadump_conf) { int i, err = -EIO; @@ -535,6 +541,7 @@ static struct fadump_ops opal_fadump_ops = { .init_fadump_mem_struct = opal_fadump_init_mem_struct, .get_kernel_metadata_size = opal_fadump_get_kernel_metadata_size, .setup_kernel_metadata = opal_fadump_setup_kernel_metadata, + .get_bootmem_min = opal_fadump_get_bootmem_min, .register_fadump = opal_fadump_register_fadump, .unregister_fadump = opal_fadump_unregister_fadump, .invalidate_fadump = opal_fadump_invalidate_fadump, @@ -547,6 +554,7 @@ int __init opal_fadump_dt_scan(struct fw_dump *fadump_conf, ulong node) { unsigned long dn; const __be32 *prop; + int i, len; /* * Check if Firmware-Assisted Dump is supported. if yes, check @@ -563,6 +571,27 @@ int __init opal_fadump_dt_scan(struct fw_dump *fadump_conf, ulong node) return 1; } + prop = of_get_flat_dt_prop(dn, "fw-load-area", &len); + if (prop) { + /* + * Each f/w load area is an (address,size) pair, + * 2 cells each, totalling 4 cells per range. + */ + for (i = 0; i < len / (sizeof(*prop) * 4); i++) { + u64 base, end; + + base = of_read_number(prop + (i * 4) + 0, 2); + end = base; + end += of_read_number(prop + (i * 4) + 2, 2); + if (end > OPAL_FADUMP_MIN_BOOT_MEM) { + pr_err("F/W load area: 0x%llx-0x%llx\n", + base, end); + pr_err("F/W version not supported!\n"); + return 1; + } + } + } + fadump_conf->ops = &opal_fadump_ops; fadump_conf->fadump_platform = FADUMP_PLATFORM_POWERNV; fadump_conf->fadump_supported = 1; diff --git a/arch/powerpc/platforms/powernv/opal-fadump.h b/arch/powerpc/platforms/powernv/opal-fadump.h index c833725..f09b0ea 100644 --- a/arch/powerpc/platforms/powernv/opal-fadump.h +++ b/arch/powerpc/platforms/powernv/opal-fadump.h @@ -16,6 +16,13 @@ #ifndef CONFIG_PRESERVE_FA_DUMP #include <asm/reg.h> +/* + * With kernel & initrd loaded at 512MB (with 256MB size), enforce a minimum + * boot memory size of 768MB to ensure f/w loading kernel and initrd doesn't + * mess with crash'ed kernel's memory during MPIPL. + */ +#define OPAL_FADUMP_MIN_BOOT_MEM (0x30000000UL) + /* OPAL FADump structure format version */ #define OPAL_FADUMP_VERSION 0x1 diff --git a/arch/powerpc/platforms/pseries/rtas-fadump.c b/arch/powerpc/platforms/pseries/rtas-fadump.c index 4372fb3..7c44bd4 100644 --- a/arch/powerpc/platforms/pseries/rtas-fadump.c +++ b/arch/powerpc/platforms/pseries/rtas-fadump.c @@ -145,6 +145,11 @@ static int rtas_fadump_setup_kernel_metadata(struct fw_dump *fadump_conf) return 0; } +static ulong rtas_fadump_get_bootmem_min(void) +{ + return RTAS_FADUMP_MIN_BOOT_MEM; +} + static int rtas_fadump_register_fadump(struct fw_dump *fadump_conf) { int rc, err = -EIO; @@ -514,6 +519,7 @@ static struct fadump_ops rtas_fadump_ops = { .init_fadump_mem_struct = rtas_fadump_init_mem_struct, .get_kernel_metadata_size = rtas_fadump_get_kernel_metadata_size, .setup_kernel_metadata = rtas_fadump_setup_kernel_metadata, + .get_bootmem_min = rtas_fadump_get_bootmem_min, .register_fadump = rtas_fadump_register_fadump, .unregister_fadump = rtas_fadump_unregister_fadump, .invalidate_fadump = rtas_fadump_invalidate_fadump, diff --git a/arch/powerpc/platforms/pseries/rtas-fadump.h b/arch/powerpc/platforms/pseries/rtas-fadump.h index 25da5b8..080e214 100644 --- a/arch/powerpc/platforms/pseries/rtas-fadump.h +++ b/arch/powerpc/platforms/pseries/rtas-fadump.h @@ -16,6 +16,17 @@ #ifndef __PPC64_RTAS_FA_DUMP_H__ #define __PPC64_RTAS_FA_DUMP_H__ +/* + * On some Power systems where RMO is 128MB, it still requires minimum of + * 256MB for kernel to boot successfully. When kdump infrastructure is + * configured to save vmcore over network, we run into OOM issue while + * loading modules related to network setup. Hence we need additional 64M + * of memory to avoid OOM issue. + */ +#define RTAS_FADUMP_MIN_BOOT_MEM (((RMA_END < (0x1UL << 28)) ? \ + (0x1UL << 28) : RMA_END) + \ + (0x1UL << 26)) + /* Firmware provided dump sections */ #define RTAS_FADUMP_CPU_STATE_DATA 0x0001 #define RTAS_FADUMP_HPTE_REGION 0x0002