Commit b74196af authored by Hari Bathini's avatar Hari Bathini Committed by Michael Ellerman
Browse files

powerpc/fadump: Fix fadump to work with a different endian capture kernel 



Dump capture would fail if capture kernel is not of the endianess as the
production kernel, because the in-memory data structure (struct
opal_fadump_mem_struct) shared across production kernel and capture
kernel assumes the same endianess for both the kernels, which doesn't
have to be true always. Fix it by having a well-defined endianess for
struct opal_fadump_mem_struct.

Signed-off-by: default avatarHari Bathini <hbathini@linux.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/161902744901.86147.14719228311655123526.stgit@hbathini
parent a84ca704

arch/powerpc/platforms/powernv/opal-fadump.c

+52 −42
Original line number Diff line number Diff line
@@ -60,7 +60,7 @@ void __init opal_fadump_dt_scan(struct fw_dump *fadump_conf, u64 node) 
	addr = be64_to_cpu(addr);

	pr_debug("Kernel metadata addr: %llx\n", addr);

	opal_fdm_active = (void *)addr;

	if (opal_fdm_active->registered_regions == 0)

	if (be16_to_cpu(opal_fdm_active->registered_regions) == 0)

		return;



	ret = opal_mpipl_query_tag(OPAL_MPIPL_TAG_BOOT_MEM, &addr);
@@ -95,17 +95,17 @@ static int opal_fadump_unregister(struct fw_dump *fadump_conf); 
static void opal_fadump_update_config(struct fw_dump *fadump_conf,

				      const struct opal_fadump_mem_struct *fdm)

{

	pr_debug("Boot memory regions count: %d\n", fdm->region_cnt);

	pr_debug("Boot memory regions count: %d\n", be16_to_cpu(fdm->region_cnt));



	/*

	 * The destination address of the first boot memory region is the

	 * destination address of boot memory regions.

	 */

	fadump_conf->boot_mem_dest_addr = fdm->rgn[0].dest;

	fadump_conf->boot_mem_dest_addr = be64_to_cpu(fdm->rgn[0].dest);

	pr_debug("Destination address of boot memory regions: %#016llx\n",

		 fadump_conf->boot_mem_dest_addr);



	fadump_conf->fadumphdr_addr = fdm->fadumphdr_addr;

	fadump_conf->fadumphdr_addr = be64_to_cpu(fdm->fadumphdr_addr);

}



/*
@@ -126,9 +126,9 @@ static void __init opal_fadump_get_config(struct fw_dump *fadump_conf, 
	fadump_conf->boot_memory_size = 0;



	pr_debug("Boot memory regions:\n");

	for (i = 0; i < fdm->region_cnt; i++) {

		base = fdm->rgn[i].src;

		size = fdm->rgn[i].size;

	for (i = 0; i < be16_to_cpu(fdm->region_cnt); i++) {

		base = be64_to_cpu(fdm->rgn[i].src);

		size = be64_to_cpu(fdm->rgn[i].size);

		pr_debug("\t[%03d] base: 0x%lx, size: 0x%lx\n", i, base, size);



		fadump_conf->boot_mem_addr[i] = base;
@@ -143,7 +143,7 @@ static void __init opal_fadump_get_config(struct fw_dump *fadump_conf, 
	 * 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;

	fadump_conf->reserve_dump_area_start = be64_to_cpu(fdm->rgn[0].dest);



	/*

	 * Rarely, but it can so happen that system crashes before all
@@ -155,13 +155,14 @@ static void __init opal_fadump_get_config(struct fw_dump *fadump_conf, 
	 * Hope the memory that could not be preserved only has pages

	 * that are usually filtered out while saving the vmcore.

	 */

	if (fdm->region_cnt > fdm->registered_regions) {

	if (be16_to_cpu(fdm->region_cnt) > be16_to_cpu(fdm->registered_regions)) {

		pr_warn("Not all memory regions were saved!!!\n");

		pr_warn("  Unsaved memory regions:\n");

		i = fdm->registered_regions;

		while (i < fdm->region_cnt) {

		i = be16_to_cpu(fdm->registered_regions);

		while (i < be16_to_cpu(fdm->region_cnt)) {

			pr_warn("\t[%03d] base: 0x%llx, size: 0x%llx\n",

				i, fdm->rgn[i].src, fdm->rgn[i].size);

				i, be64_to_cpu(fdm->rgn[i].src),

				be64_to_cpu(fdm->rgn[i].size));

			i++;

		}
@@ -170,7 +171,7 @@ static void __init opal_fadump_get_config(struct fw_dump *fadump_conf, 
	}



	fadump_conf->boot_mem_top = (fadump_conf->boot_memory_size + hole_size);

	fadump_conf->boot_mem_regs_cnt = fdm->region_cnt;

	fadump_conf->boot_mem_regs_cnt = be16_to_cpu(fdm->region_cnt);

	opal_fadump_update_config(fadump_conf, fdm);

}
@@ -178,34 +179,37 @@ static void __init opal_fadump_get_config(struct fw_dump *fadump_conf, 
static void opal_fadump_init_metadata(struct opal_fadump_mem_struct *fdm)

{

	fdm->version = OPAL_FADUMP_VERSION;

	fdm->region_cnt = 0;

	fdm->registered_regions = 0;

	fdm->fadumphdr_addr = 0;

	fdm->region_cnt = cpu_to_be16(0);

	fdm->registered_regions = cpu_to_be16(0);

	fdm->fadumphdr_addr = cpu_to_be64(0);

}



static u64 opal_fadump_init_mem_struct(struct fw_dump *fadump_conf)

{

	u64 addr = fadump_conf->reserve_dump_area_start;

	u16 reg_cnt;

	int i;



	opal_fdm = __va(fadump_conf->kernel_metadata);

	opal_fadump_init_metadata(opal_fdm);



	/* Boot memory regions */

	reg_cnt = be16_to_cpu(opal_fdm->region_cnt);

	for (i = 0; i < fadump_conf->boot_mem_regs_cnt; i++) {

		opal_fdm->rgn[i].src	= fadump_conf->boot_mem_addr[i];

		opal_fdm->rgn[i].dest	= addr;

		opal_fdm->rgn[i].size	= fadump_conf->boot_mem_sz[i];

		opal_fdm->rgn[i].src	= cpu_to_be64(fadump_conf->boot_mem_addr[i]);

		opal_fdm->rgn[i].dest	= cpu_to_be64(addr);

		opal_fdm->rgn[i].size	= cpu_to_be64(fadump_conf->boot_mem_sz[i]);



		opal_fdm->region_cnt++;

		reg_cnt++;

		addr += fadump_conf->boot_mem_sz[i];

	}

	opal_fdm->region_cnt = cpu_to_be16(reg_cnt);



	/*

	 * Kernel metadata is passed to f/w and retrieved in capture kerenl.

	 * So, use it to save fadump header address instead of calculating it.

	 */

	opal_fdm->fadumphdr_addr = (opal_fdm->rgn[0].dest +

	opal_fdm->fadumphdr_addr = cpu_to_be64(be64_to_cpu(opal_fdm->rgn[0].dest) +

					       fadump_conf->boot_memory_size);



	opal_fadump_update_config(fadump_conf, opal_fdm);
@@ -269,18 +273,21 @@ static u64 opal_fadump_get_bootmem_min(void) 
static int opal_fadump_register(struct fw_dump *fadump_conf)

{

	s64 rc = OPAL_PARAMETER;

	u16 registered_regs;

	int i, err = -EIO;



	for (i = 0; i < opal_fdm->region_cnt; i++) {

	registered_regs = be16_to_cpu(opal_fdm->registered_regions);

	for (i = 0; i < be16_to_cpu(opal_fdm->region_cnt); i++) {

		rc = opal_mpipl_update(OPAL_MPIPL_ADD_RANGE,

				       opal_fdm->rgn[i].src,

				       opal_fdm->rgn[i].dest,

				       opal_fdm->rgn[i].size);

				       be64_to_cpu(opal_fdm->rgn[i].src),

				       be64_to_cpu(opal_fdm->rgn[i].dest),

				       be64_to_cpu(opal_fdm->rgn[i].size));

		if (rc != OPAL_SUCCESS)

			break;



		opal_fdm->registered_regions++;

		registered_regs++;

	}

	opal_fdm->registered_regions = cpu_to_be16(registered_regs);



	switch (rc) {

	case OPAL_SUCCESS:
@@ -291,7 +298,8 @@ static int opal_fadump_register(struct fw_dump *fadump_conf) 
	case OPAL_RESOURCE:

		/* If MAX regions limit in f/w is hit, warn and proceed. */

		pr_warn("%d regions could not be registered for MPIPL as MAX limit is reached!\n",

			(opal_fdm->region_cnt - opal_fdm->registered_regions));

			(be16_to_cpu(opal_fdm->region_cnt) -

			 be16_to_cpu(opal_fdm->registered_regions)));

		fadump_conf->dump_registered = 1;

		err = 0;

		break;
@@ -312,7 +320,7 @@ static int opal_fadump_register(struct fw_dump *fadump_conf) 
	 * If some regions were registered before OPAL_MPIPL_ADD_RANGE

	 * OPAL call failed, unregister all regions.

	 */

	if ((err < 0) && (opal_fdm->registered_regions > 0))

	if ((err < 0) && (be16_to_cpu(opal_fdm->registered_regions) > 0))

		opal_fadump_unregister(fadump_conf);



	return err;
@@ -328,7 +336,7 @@ static int opal_fadump_unregister(struct fw_dump *fadump_conf) 
		return -EIO;

	}



	opal_fdm->registered_regions = 0;

	opal_fdm->registered_regions = cpu_to_be16(0);

	fadump_conf->dump_registered = 0;

	return 0;

}
@@ -563,19 +571,20 @@ static void opal_fadump_region_show(struct fw_dump *fadump_conf, 
	else

		fdm_ptr = opal_fdm;



	for (i = 0; i < fdm_ptr->region_cnt; i++) {

	for (i = 0; i < be16_to_cpu(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;

		    (i < be16_to_cpu(fdm_ptr->registered_regions)))

			dumped_bytes = be64_to_cpu(fdm_ptr->rgn[i].size);



		seq_printf(m, "DUMP: Src: %#016llx, Dest: %#016llx, ",

			   fdm_ptr->rgn[i].src, fdm_ptr->rgn[i].dest);

			   be64_to_cpu(fdm_ptr->rgn[i].src),

			   be64_to_cpu(fdm_ptr->rgn[i].dest));

		seq_printf(m, "Size: %#llx, Dumped: %#llx bytes\n",

			   fdm_ptr->rgn[i].size, dumped_bytes);

			   be64_to_cpu(fdm_ptr->rgn[i].size), dumped_bytes);

	}



	/* Dump is active. Show reserved area start address. */
@@ -624,6 +633,7 @@ void __init opal_fadump_dt_scan(struct fw_dump *fadump_conf, u64 node) 
{

	const __be32 *prop;

	unsigned long dn;

	__be64 be_addr;

	u64 addr = 0;

	int i, len;

	s64 ret;
@@ -680,13 +690,13 @@ void __init opal_fadump_dt_scan(struct fw_dump *fadump_conf, u64 node) 
	if (!prop)

		return;



	ret = opal_mpipl_query_tag(OPAL_MPIPL_TAG_KERNEL, &addr);

	if ((ret != OPAL_SUCCESS) || !addr) {

	ret = opal_mpipl_query_tag(OPAL_MPIPL_TAG_KERNEL, &be_addr);

	if ((ret != OPAL_SUCCESS) || !be_addr) {

		pr_err("Failed to get Kernel metadata (%lld)\n", ret);

		return;

	}



	addr = be64_to_cpu(addr);

	addr = be64_to_cpu(be_addr);

	pr_debug("Kernel metadata addr: %llx\n", addr);



	opal_fdm_active = __va(addr);
@@ -697,14 +707,14 @@ void __init opal_fadump_dt_scan(struct fw_dump *fadump_conf, u64 node) 
	}



	/* Kernel regions not registered with f/w for MPIPL */

	if (opal_fdm_active->registered_regions == 0) {

	if (be16_to_cpu(opal_fdm_active->registered_regions) == 0) {

		opal_fdm_active = NULL;

		return;

	}



	ret = opal_mpipl_query_tag(OPAL_MPIPL_TAG_CPU, &addr);

	if (addr) {

		addr = be64_to_cpu(addr);

	ret = opal_mpipl_query_tag(OPAL_MPIPL_TAG_CPU, &be_addr);

	if (be_addr) {

		addr = be64_to_cpu(be_addr);

		pr_debug("CPU metadata addr: %llx\n", addr);

		opal_cpu_metadata = __va(addr);

	}

arch/powerpc/platforms/powernv/opal-fadump.h

+5 −5
Original line number Diff line number Diff line
@@ -31,14 +31,14 @@ 
 * OPAL FADump kernel metadata

 *

 * The address of this structure will be registered with f/w for retrieving

 * and processing during crash dump.

 * in the capture kernel to process the crash dump.

 */

struct opal_fadump_mem_struct {

	u8	version;

	u8	reserved[3];

	u16	region_cnt;		/* number of regions */

	u16	registered_regions;	/* Regions registered for MPIPL */

	u64	fadumphdr_addr;

	__be16	region_cnt;		/* number of regions */

	__be16	registered_regions;	/* Regions registered for MPIPL */

	__be64	fadumphdr_addr;

	struct opal_mpipl_region	rgn[FADUMP_MAX_MEM_REGS];

} __packed;
@@ -135,7 +135,7 @@ static inline void opal_fadump_read_regs(char *bufp, unsigned int regs_cnt, 
	for (i = 0; i < regs_cnt; i++, bufp += reg_entry_size) {

		reg_entry = (struct hdat_fadump_reg_entry *)bufp;

		val = (cpu_endian ? be64_to_cpu(reg_entry->reg_val) :

		       reg_entry->reg_val);

		       (u64)(reg_entry->reg_val));

		opal_fadump_set_regval_regnum(regs,

					      be32_to_cpu(reg_entry->reg_type),

					      be32_to_cpu(reg_entry->reg_num),