* [PATCH v2 00/12] ppc64: enable kdump support for kexec_file_load syscall
@ 2020-07-02 19:53 Hari Bathini
2020-07-02 19:54 ` [PATCH v2 01/12] kexec_file: allow archs to handle special regions while locating memory hole Hari Bathini
` (12 more replies)
0 siblings, 13 replies; 16+ messages in thread
From: Hari Bathini @ 2020-07-02 19:53 UTC (permalink / raw)
To: Michael Ellerman, Andrew Morton
Cc: Pingfan Liu, Kexec-ml, Petr Tesarik, Mahesh J Salgaonkar,
Sourabh Jain, lkml, linuxppc-dev, Mimi Zohar, Vivek Goyal,
Dave Young, Thiago Jung Bauermann, Eric Biederman
This patch series enables kdump support for kexec_file_load system
call (kexec -s -p) on PPC64. The changes are inspired from kexec-tools
code but heavily modified for kernel consumption. There is scope to
expand purgatory to verify sha256 digest along with other improvements
in purgatory code. Will deal with those changes in a separate patch
series later.
The first patch adds a weak arch_kexec_locate_mem_hole() function to
override locate memory hole logic suiting arch needs. There are some
special regions in ppc64 which should be avoided while loading buffer
& there are multiple callers to kexec_add_buffer making it complicated
to maintain range sanity and using generic lookup at the same time.
The second patch marks ppc64 specific code within arch/powerpc/kexec
and arch/powerpc/purgatory to make the subsequent code changes easy
to understand.
The next patch adds helper function to setup different memory ranges
needed for loading kdump kernel, booting into it and exporting the
crashing kernel's elfcore.
The fourth patch overrides arch_kexec_locate_mem_hole() function to
locate memory hole for kdump segments by accounting for the special
memory regions, referred to as excluded memory ranges, and sets
kbuf->mem when a suitable memory region is found.
The fifth patch moves walk_drmem_lmbs() out of .init section with
a few changes to reuse it for setting up kdump kernel's usable memory
ranges. The next patch uses walk_drmem_lmbs() to look up the LMBs
and set linux,drconf-usable-memory & linux,usable-memory properties
in order to restrict kdump kernel's memory usage.
The seventh patch adds relocation support for the purgatory. Patch 8
helps setup the stack for the purgatory. The next patch setups up
backup region as a segment while loading kdump kernel and teaches
purgatory to copy it from source to destination.
Patch 10 builds the elfcore header for the running kernel & passes
the info to kdump kernel via "elfcorehdr=" parameter to export as
/proc/vmcore file. The next patch sets up the memory reserve map
for the kexec kernel and also claims kdump support for kdump as
all the necessary changes are added.
The last patch fixes a lookup issue for `kexec -l -s` case when
memory is reserved for crashkernel.
Tested the changes successfully on P8, P9 lpars, couple of OpenPOWER
boxes and a simulator.
Changes in v2:
* Introduced arch_kexec_locate_mem_hole() for override and dropped
weak arch_kexec_add_buffer().
* Addressed warnings reported by lkp.
* Added patch to address kexec load issue when memory is reserved
for crashkernel.
* Used the appropriate license header for the new files added.
* Added an option to merge ranges to minimize reallocations while
adding memory ranges.
* Dropped within_crashkernel parameter for add_opal_mem_range() &
add_rtas_mem_range() functions as it is not really needed.
---
Hari Bathini (12):
kexec_file: allow archs to handle special regions while locating memory hole
powerpc/kexec_file: mark PPC64 specific code
powerpc/kexec_file: add helper functions for getting memory ranges
ppc64/kexec_file: avoid stomping memory used by special regions
powerpc/drmem: make lmb walk a bit more flexible
ppc64/kexec_file: restrict memory usage of kdump kernel
ppc64/kexec_file: add support to relocate purgatory
ppc64/kexec_file: setup the stack for purgatory
ppc64/kexec_file: setup backup region for kdump kernel
ppc64/kexec_file: prepare elfcore header for crashing kernel
ppc64/kexec_file: add appropriate regions for memory reserve map
ppc64/kexec_file: fix kexec load failure with lack of memory hole
arch/powerpc/include/asm/crashdump-ppc64.h | 15
arch/powerpc/include/asm/drmem.h | 9
arch/powerpc/include/asm/kexec.h | 35 +
arch/powerpc/include/asm/kexec_ranges.h | 18
arch/powerpc/include/asm/purgatory.h | 11
arch/powerpc/kernel/prom.c | 13
arch/powerpc/kexec/Makefile | 2
arch/powerpc/kexec/elf_64.c | 35 +
arch/powerpc/kexec/file_load.c | 78 +
arch/powerpc/kexec/file_load_64.c | 1509 ++++++++++++++++++++++++++++
arch/powerpc/kexec/ranges.c | 397 +++++++
arch/powerpc/mm/drmem.c | 87 +-
arch/powerpc/mm/numa.c | 13
arch/powerpc/purgatory/Makefile | 28 -
arch/powerpc/purgatory/purgatory_64.c | 36 +
arch/powerpc/purgatory/trampoline.S | 117 --
arch/powerpc/purgatory/trampoline_64.S | 175 +++
include/linux/kexec.h | 29 -
kernel/kexec_file.c | 16
19 files changed, 2413 insertions(+), 210 deletions(-)
create mode 100644 arch/powerpc/include/asm/crashdump-ppc64.h
create mode 100644 arch/powerpc/include/asm/kexec_ranges.h
create mode 100644 arch/powerpc/include/asm/purgatory.h
create mode 100644 arch/powerpc/kexec/file_load_64.c
create mode 100644 arch/powerpc/kexec/ranges.c
create mode 100644 arch/powerpc/purgatory/purgatory_64.c
delete mode 100644 arch/powerpc/purgatory/trampoline.S
create mode 100644 arch/powerpc/purgatory/trampoline_64.S
^ permalink raw reply [flat|nested] 16+ messages in thread
* [PATCH v2 01/12] kexec_file: allow archs to handle special regions while locating memory hole
2020-07-02 19:53 [PATCH v2 00/12] ppc64: enable kdump support for kexec_file_load syscall Hari Bathini
@ 2020-07-02 19:54 ` Hari Bathini
2020-07-06 9:07 ` Dave Young
2020-07-02 19:54 ` [PATCH v2 02/12] powerpc/kexec_file: mark PPC64 specific code Hari Bathini
` (11 subsequent siblings)
12 siblings, 1 reply; 16+ messages in thread
From: Hari Bathini @ 2020-07-02 19:54 UTC (permalink / raw)
To: Michael Ellerman, Andrew Morton
Cc: kernel test robot, Pingfan Liu, Kexec-ml, Petr Tesarik,
Mahesh J Salgaonkar, Mimi Zohar, lkml, linuxppc-dev,
Sourabh Jain, Vivek Goyal, Dave Young, Thiago Jung Bauermann,
Eric Biederman
Some architectures may have special memory regions, within the given
memory range, which can't be used for the buffer in a kexec segment.
Implement weak arch_kexec_locate_mem_hole() definition which arch code
may override, to take care of special regions, while trying to locate
a memory hole.
Also, add the missing declarations for arch overridable functions and
and drop the __weak descriptors in the declarations to avoid non-weak
definitions from becoming weak.
Reported-by: kernel test robot <lkp@intel.com>
[lkp: In v1, arch_kimage_file_post_load_cleanup() declaration was missing]
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
---
Changes in v2:
* Introduced arch_kexec_locate_mem_hole() for override and dropped
weak arch_kexec_add_buffer().
* Dropped __weak identifier for arch overridable functions.
* Fixed the missing declaration for arch_kimage_file_post_load_cleanup()
reported by lkp. lkp report for reference:
- https://lore.kernel.org/patchwork/patch/1264418/
include/linux/kexec.h | 29 ++++++++++++++++++-----------
kernel/kexec_file.c | 16 ++++++++++++++--
2 files changed, 32 insertions(+), 13 deletions(-)
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index ea67910..9e93bef 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -183,17 +183,24 @@ int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name,
bool get_value);
void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name);
-int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
- unsigned long buf_len);
-void * __weak arch_kexec_kernel_image_load(struct kimage *image);
-int __weak arch_kexec_apply_relocations_add(struct purgatory_info *pi,
- Elf_Shdr *section,
- const Elf_Shdr *relsec,
- const Elf_Shdr *symtab);
-int __weak arch_kexec_apply_relocations(struct purgatory_info *pi,
- Elf_Shdr *section,
- const Elf_Shdr *relsec,
- const Elf_Shdr *symtab);
+/* Architectures may override the below functions */
+int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
+ unsigned long buf_len);
+void *arch_kexec_kernel_image_load(struct kimage *image);
+int arch_kexec_apply_relocations_add(struct purgatory_info *pi,
+ Elf_Shdr *section,
+ const Elf_Shdr *relsec,
+ const Elf_Shdr *symtab);
+int arch_kexec_apply_relocations(struct purgatory_info *pi,
+ Elf_Shdr *section,
+ const Elf_Shdr *relsec,
+ const Elf_Shdr *symtab);
+int arch_kimage_file_post_load_cleanup(struct kimage *image);
+#ifdef CONFIG_KEXEC_SIG
+int arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
+ unsigned long buf_len);
+#endif
+int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf);
extern int kexec_add_buffer(struct kexec_buf *kbuf);
int kexec_locate_mem_hole(struct kexec_buf *kbuf);
diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index 09cc78d..e89912d 100644
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -636,6 +636,19 @@ int kexec_locate_mem_hole(struct kexec_buf *kbuf)
}
/**
+ * arch_kexec_locate_mem_hole - Find free memory to place the segments.
+ * @kbuf: Parameters for the memory search.
+ *
+ * On success, kbuf->mem will have the start address of the memory region found.
+ *
+ * Return: 0 on success, negative errno on error.
+ */
+int __weak arch_kexec_locate_mem_hole(struct kexec_buf *kbuf)
+{
+ return kexec_locate_mem_hole(kbuf);
+}
+
+/**
* kexec_add_buffer - place a buffer in a kexec segment
* @kbuf: Buffer contents and memory parameters.
*
@@ -647,7 +660,6 @@ int kexec_locate_mem_hole(struct kexec_buf *kbuf)
*/
int kexec_add_buffer(struct kexec_buf *kbuf)
{
-
struct kexec_segment *ksegment;
int ret;
@@ -675,7 +687,7 @@ int kexec_add_buffer(struct kexec_buf *kbuf)
kbuf->buf_align = max(kbuf->buf_align, PAGE_SIZE);
/* Walk the RAM ranges and allocate a suitable range for the buffer */
- ret = kexec_locate_mem_hole(kbuf);
+ ret = arch_kexec_locate_mem_hole(kbuf);
if (ret)
return ret;
^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v2 02/12] powerpc/kexec_file: mark PPC64 specific code
2020-07-02 19:53 [PATCH v2 00/12] ppc64: enable kdump support for kexec_file_load syscall Hari Bathini
2020-07-02 19:54 ` [PATCH v2 01/12] kexec_file: allow archs to handle special regions while locating memory hole Hari Bathini
@ 2020-07-02 19:54 ` Hari Bathini
2020-07-10 7:52 ` Laurent Dufour
2020-07-02 19:54 ` [PATCH v2 03/12] powerpc/kexec_file: add helper functions for getting memory ranges Hari Bathini
` (10 subsequent siblings)
12 siblings, 1 reply; 16+ messages in thread
From: Hari Bathini @ 2020-07-02 19:54 UTC (permalink / raw)
To: Michael Ellerman, Andrew Morton
Cc: Pingfan Liu, Kexec-ml, Petr Tesarik, Mahesh J Salgaonkar,
Sourabh Jain, lkml, linuxppc-dev, Mimi Zohar, Vivek Goyal,
Dave Young, Thiago Jung Bauermann, Eric Biederman
Some of the kexec_file_load code isn't PPC64 specific. Move PPC64
specific code from kexec/file_load.c to kexec/file_load_64.c. Also,
rename purgatory/trampoline.S to purgatory/trampoline_64.S in the
same spirit.
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
---
Changes in v2:
* No changes.
arch/powerpc/include/asm/kexec.h | 11 +++
arch/powerpc/kexec/Makefile | 2 -
arch/powerpc/kexec/elf_64.c | 7 +-
arch/powerpc/kexec/file_load.c | 37 ++--------
arch/powerpc/kexec/file_load_64.c | 108 ++++++++++++++++++++++++++++++
arch/powerpc/purgatory/Makefile | 4 +
arch/powerpc/purgatory/trampoline.S | 117 --------------------------------
arch/powerpc/purgatory/trampoline_64.S | 117 ++++++++++++++++++++++++++++++++
8 files changed, 248 insertions(+), 155 deletions(-)
create mode 100644 arch/powerpc/kexec/file_load_64.c
delete mode 100644 arch/powerpc/purgatory/trampoline.S
create mode 100644 arch/powerpc/purgatory/trampoline_64.S
diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
index c684768..7008ea1 100644
--- a/arch/powerpc/include/asm/kexec.h
+++ b/arch/powerpc/include/asm/kexec.h
@@ -114,8 +114,17 @@ int setup_purgatory(struct kimage *image, const void *slave_code,
unsigned long fdt_load_addr);
int setup_new_fdt(const struct kimage *image, void *fdt,
unsigned long initrd_load_addr, unsigned long initrd_len,
- const char *cmdline);
+ const char *cmdline, int *node);
int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size);
+
+#ifdef CONFIG_PPC64
+int setup_purgatory_ppc64(struct kimage *image, const void *slave_code,
+ const void *fdt, unsigned long kernel_load_addr,
+ unsigned long fdt_load_addr);
+int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
+ unsigned long initrd_load_addr,
+ unsigned long initrd_len, const char *cmdline);
+#endif /* CONFIG_PPC64 */
#endif /* CONFIG_KEXEC_FILE */
#else /* !CONFIG_KEXEC_CORE */
diff --git a/arch/powerpc/kexec/Makefile b/arch/powerpc/kexec/Makefile
index 86380c6..67c3553 100644
--- a/arch/powerpc/kexec/Makefile
+++ b/arch/powerpc/kexec/Makefile
@@ -7,7 +7,7 @@ obj-y += core.o crash.o core_$(BITS).o
obj-$(CONFIG_PPC32) += relocate_32.o
-obj-$(CONFIG_KEXEC_FILE) += file_load.o elf_$(BITS).o
+obj-$(CONFIG_KEXEC_FILE) += file_load.o file_load_$(BITS).o elf_$(BITS).o
ifdef CONFIG_HAVE_IMA_KEXEC
ifdef CONFIG_IMA
diff --git a/arch/powerpc/kexec/elf_64.c b/arch/powerpc/kexec/elf_64.c
index 3072fd6..23ad04c 100644
--- a/arch/powerpc/kexec/elf_64.c
+++ b/arch/powerpc/kexec/elf_64.c
@@ -88,7 +88,8 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
goto out;
}
- ret = setup_new_fdt(image, fdt, initrd_load_addr, initrd_len, cmdline);
+ ret = setup_new_fdt_ppc64(image, fdt, initrd_load_addr,
+ initrd_len, cmdline);
if (ret)
goto out;
@@ -107,8 +108,8 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
pr_debug("Loaded device tree at 0x%lx\n", fdt_load_addr);
slave_code = elf_info.buffer + elf_info.proghdrs[0].p_offset;
- ret = setup_purgatory(image, slave_code, fdt, kernel_load_addr,
- fdt_load_addr);
+ ret = setup_purgatory_ppc64(image, slave_code, fdt, kernel_load_addr,
+ fdt_load_addr);
if (ret)
pr_err("Error setting up the purgatory.\n");
diff --git a/arch/powerpc/kexec/file_load.c b/arch/powerpc/kexec/file_load.c
index 143c917..99a2c4d 100644
--- a/arch/powerpc/kexec/file_load.c
+++ b/arch/powerpc/kexec/file_load.c
@@ -1,6 +1,6 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
- * ppc64 code to implement the kexec_file_load syscall
+ * powerpc code to implement the kexec_file_load syscall
*
* Copyright (C) 2004 Adam Litke (agl@us.ibm.com)
* Copyright (C) 2004 IBM Corp.
@@ -16,26 +16,10 @@
#include <linux/slab.h>
#include <linux/kexec.h>
-#include <linux/of_fdt.h>
#include <linux/libfdt.h>
#include <asm/ima.h>
-#define SLAVE_CODE_SIZE 256
-
-const struct kexec_file_ops * const kexec_file_loaders[] = {
- &kexec_elf64_ops,
- NULL
-};
-
-int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
- unsigned long buf_len)
-{
- /* We don't support crash kernels yet. */
- if (image->type == KEXEC_TYPE_CRASH)
- return -EOPNOTSUPP;
-
- return kexec_image_probe_default(image, buf, buf_len);
-}
+#define SLAVE_CODE_SIZE 256 /* First 0x100 bytes */
/**
* setup_purgatory - initialize the purgatory's global variables
@@ -127,24 +111,17 @@ int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size)
* @initrd_len: Size of the next initrd, or 0 if there will be none.
* @cmdline: Command line for the next kernel, or NULL if there will
* be none.
+ * @chosen_node: Set this output parameter to chosen_node.
*
* Return: 0 on success, or negative errno on error.
*/
int setup_new_fdt(const struct kimage *image, void *fdt,
unsigned long initrd_load_addr, unsigned long initrd_len,
- const char *cmdline)
+ const char *cmdline, int *node)
{
int ret, chosen_node;
const void *prop;
- /* Remove memory reservation for the current device tree. */
- ret = delete_fdt_mem_rsv(fdt, __pa(initial_boot_params),
- fdt_totalsize(initial_boot_params));
- if (ret == 0)
- pr_debug("Removed old device tree reservation.\n");
- else if (ret != -ENOENT)
- return ret;
-
chosen_node = fdt_path_offset(fdt, "/chosen");
if (chosen_node == -FDT_ERR_NOTFOUND) {
chosen_node = fdt_add_subnode(fdt, fdt_path_offset(fdt, "/"),
@@ -157,6 +134,8 @@ int setup_new_fdt(const struct kimage *image, void *fdt,
pr_err("Malformed device tree: error reading /chosen.\n");
return -EINVAL;
}
+ if (node)
+ *node = chosen_node;
/* Did we boot using an initrd? */
prop = fdt_getprop(fdt, chosen_node, "linux,initrd-start", NULL);
@@ -242,10 +221,6 @@ int setup_new_fdt(const struct kimage *image, void *fdt,
return ret;
}
- ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
- if (ret)
- goto err;
-
return 0;
err:
diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
new file mode 100644
index 0000000..e6bff960
--- /dev/null
+++ b/arch/powerpc/kexec/file_load_64.c
@@ -0,0 +1,108 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ppc64 code to implement the kexec_file_load syscall
+ *
+ * Copyright (C) 2004 Adam Litke (agl@us.ibm.com)
+ * Copyright (C) 2004 IBM Corp.
+ * Copyright (C) 2004,2005 Milton D Miller II, IBM Corporation
+ * Copyright (C) 2005 R Sharada (sharada@in.ibm.com)
+ * Copyright (C) 2006 Mohan Kumar M (mohan@in.ibm.com)
+ * Copyright (C) 2020 IBM Corporation
+ *
+ * Based on kexec-tools' kexec-ppc64.c, kexec-elf-rel-ppc64.c, fs2dt.c.
+ * Heavily modified for the kernel by
+ * Hari Bathini <hbathini@linux.ibm.com>.
+ */
+
+#include <linux/kexec.h>
+#include <linux/of_fdt.h>
+#include <linux/libfdt.h>
+
+const struct kexec_file_ops * const kexec_file_loaders[] = {
+ &kexec_elf64_ops,
+ NULL
+};
+
+/**
+ * setup_purgatory_ppc64 - initialize PPC64 specific purgatory's global
+ * variables and call setup_purgatory() to initialize
+ * common global variable.
+ * @image: kexec image.
+ * @slave_code: Slave code for the purgatory.
+ * @fdt: Flattened device tree for the next kernel.
+ * @kernel_load_addr: Address where the kernel is loaded.
+ * @fdt_load_addr: Address where the flattened device tree is loaded.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int setup_purgatory_ppc64(struct kimage *image, const void *slave_code,
+ const void *fdt, unsigned long kernel_load_addr,
+ unsigned long fdt_load_addr)
+{
+ int ret;
+
+ ret = setup_purgatory(image, slave_code, fdt, kernel_load_addr,
+ fdt_load_addr);
+ if (ret)
+ pr_err("Failed to setup purgatory symbols");
+ return ret;
+}
+
+/**
+ * setup_new_fdt_ppc64 - Update the flattend device-tree of the kernel
+ * being loaded.
+ * @image: kexec image being loaded.
+ * @fdt: Flattened device tree for the next kernel.
+ * @initrd_load_addr: Address where the next initrd will be loaded.
+ * @initrd_len: Size of the next initrd, or 0 if there will be none.
+ * @cmdline: Command line for the next kernel, or NULL if there will
+ * be none.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
+ unsigned long initrd_load_addr,
+ unsigned long initrd_len, const char *cmdline)
+{
+ int chosen_node, ret;
+
+ /* Remove memory reservation for the current device tree. */
+ ret = delete_fdt_mem_rsv(fdt, __pa(initial_boot_params),
+ fdt_totalsize(initial_boot_params));
+ if (ret == 0)
+ pr_debug("Removed old device tree reservation.\n");
+ else if (ret != -ENOENT) {
+ pr_err("Failed to remove old device-tree reservation.\n");
+ return ret;
+ }
+
+ ret = setup_new_fdt(image, fdt, initrd_load_addr, initrd_len,
+ cmdline, &chosen_node);
+ if (ret)
+ return ret;
+
+ ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
+ if (ret)
+ pr_err("Failed to update device-tree with linux,booted-from-kexec\n");
+
+ return ret;
+}
+
+/**
+ * arch_kexec_kernel_image_probe - Does additional handling needed to setup
+ * kexec segments.
+ * @image: kexec image being loaded.
+ * @buf: Buffer pointing to elf data.
+ * @buf_len: Length of the buffer.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
+ unsigned long buf_len)
+{
+ /* We don't support crash kernels yet. */
+ if (image->type == KEXEC_TYPE_CRASH)
+ return -EOPNOTSUPP;
+
+ return kexec_image_probe_default(image, buf, buf_len);
+}
diff --git a/arch/powerpc/purgatory/Makefile b/arch/powerpc/purgatory/Makefile
index 7c6d8b1..348f5958 100644
--- a/arch/powerpc/purgatory/Makefile
+++ b/arch/powerpc/purgatory/Makefile
@@ -2,11 +2,11 @@
KASAN_SANITIZE := n
-targets += trampoline.o purgatory.ro kexec-purgatory.c
+targets += trampoline_$(BITS).o purgatory.ro kexec-purgatory.c
LDFLAGS_purgatory.ro := -e purgatory_start -r --no-undefined
-$(obj)/purgatory.ro: $(obj)/trampoline.o FORCE
+$(obj)/purgatory.ro: $(obj)/trampoline_$(BITS).o FORCE
$(call if_changed,ld)
quiet_cmd_bin2c = BIN2C $@
diff --git a/arch/powerpc/purgatory/trampoline.S b/arch/powerpc/purgatory/trampoline.S
deleted file mode 100644
index a5a83c3..0000000
--- a/arch/powerpc/purgatory/trampoline.S
+++ /dev/null
@@ -1,117 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
-/*
- * kexec trampoline
- *
- * Based on code taken from kexec-tools and kexec-lite.
- *
- * Copyright (C) 2004 - 2005, Milton D Miller II, IBM Corporation
- * Copyright (C) 2006, Mohan Kumar M, IBM Corporation
- * Copyright (C) 2013, Anton Blanchard, IBM Corporation
- */
-
-#include <asm/asm-compat.h>
-
- .machine ppc64
- .balign 256
- .globl purgatory_start
-purgatory_start:
- b master
-
- /* ABI: possible run_at_load flag at 0x5c */
- .org purgatory_start + 0x5c
- .globl run_at_load
-run_at_load:
- .long 0
- .size run_at_load, . - run_at_load
-
- /* ABI: slaves start at 60 with r3=phys */
- .org purgatory_start + 0x60
-slave:
- b .
- /* ABI: end of copied region */
- .org purgatory_start + 0x100
- .size purgatory_start, . - purgatory_start
-
-/*
- * The above 0x100 bytes at purgatory_start are replaced with the
- * code from the kernel (or next stage) by setup_purgatory().
- */
-
-master:
- or %r1,%r1,%r1 /* low priority to let other threads catchup */
- isync
- mr %r17,%r3 /* save cpu id to r17 */
- mr %r15,%r4 /* save physical address in reg15 */
-
- or %r3,%r3,%r3 /* ok now to high priority, lets boot */
- lis %r6,0x1
- mtctr %r6 /* delay a bit for slaves to catch up */
- bdnz . /* before we overwrite 0-100 again */
-
- bl 0f /* Work out where we're running */
-0: mflr %r18
-
- /* load device-tree address */
- ld %r3, (dt_offset - 0b)(%r18)
- mr %r16,%r3 /* save dt address in reg16 */
- li %r4,20
- LWZX_BE %r6,%r3,%r4 /* fetch __be32 version number at byte 20 */
- cmpwi %cr0,%r6,2 /* v2 or later? */
- blt 1f
- li %r4,28
- STWX_BE %r17,%r3,%r4 /* Store my cpu as __be32 at byte 28 */
-1:
- /* load the kernel address */
- ld %r4,(kernel - 0b)(%r18)
-
- /* load the run_at_load flag */
- /* possibly patched by kexec */
- ld %r6,(run_at_load - 0b)(%r18)
- /* and patch it into the kernel */
- stw %r6,(0x5c)(%r4)
-
- mr %r3,%r16 /* restore dt address */
-
- li %r5,0 /* r5 will be 0 for kernel */
-
- mfmsr %r11
- andi. %r10,%r11,1 /* test MSR_LE */
- bne .Little_endian
-
- mtctr %r4 /* prepare branch to */
- bctr /* start kernel */
-
-.Little_endian:
- mtsrr0 %r4 /* prepare branch to */
-
- clrrdi %r11,%r11,1 /* clear MSR_LE */
- mtsrr1 %r11
-
- rfid /* update MSR and start kernel */
-
-
- .balign 8
- .globl kernel
-kernel:
- .8byte 0x0
- .size kernel, . - kernel
-
- .balign 8
- .globl dt_offset
-dt_offset:
- .8byte 0x0
- .size dt_offset, . - dt_offset
-
-
- .data
- .balign 8
-.globl purgatory_sha256_digest
-purgatory_sha256_digest:
- .skip 32
- .size purgatory_sha256_digest, . - purgatory_sha256_digest
-
- .balign 8
-.globl purgatory_sha_regions
-purgatory_sha_regions:
- .skip 8 * 2 * 16
- .size purgatory_sha_regions, . - purgatory_sha_regions
diff --git a/arch/powerpc/purgatory/trampoline_64.S b/arch/powerpc/purgatory/trampoline_64.S
new file mode 100644
index 0000000..a5a83c3
--- /dev/null
+++ b/arch/powerpc/purgatory/trampoline_64.S
@@ -0,0 +1,117 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * kexec trampoline
+ *
+ * Based on code taken from kexec-tools and kexec-lite.
+ *
+ * Copyright (C) 2004 - 2005, Milton D Miller II, IBM Corporation
+ * Copyright (C) 2006, Mohan Kumar M, IBM Corporation
+ * Copyright (C) 2013, Anton Blanchard, IBM Corporation
+ */
+
+#include <asm/asm-compat.h>
+
+ .machine ppc64
+ .balign 256
+ .globl purgatory_start
+purgatory_start:
+ b master
+
+ /* ABI: possible run_at_load flag at 0x5c */
+ .org purgatory_start + 0x5c
+ .globl run_at_load
+run_at_load:
+ .long 0
+ .size run_at_load, . - run_at_load
+
+ /* ABI: slaves start at 60 with r3=phys */
+ .org purgatory_start + 0x60
+slave:
+ b .
+ /* ABI: end of copied region */
+ .org purgatory_start + 0x100
+ .size purgatory_start, . - purgatory_start
+
+/*
+ * The above 0x100 bytes at purgatory_start are replaced with the
+ * code from the kernel (or next stage) by setup_purgatory().
+ */
+
+master:
+ or %r1,%r1,%r1 /* low priority to let other threads catchup */
+ isync
+ mr %r17,%r3 /* save cpu id to r17 */
+ mr %r15,%r4 /* save physical address in reg15 */
+
+ or %r3,%r3,%r3 /* ok now to high priority, lets boot */
+ lis %r6,0x1
+ mtctr %r6 /* delay a bit for slaves to catch up */
+ bdnz . /* before we overwrite 0-100 again */
+
+ bl 0f /* Work out where we're running */
+0: mflr %r18
+
+ /* load device-tree address */
+ ld %r3, (dt_offset - 0b)(%r18)
+ mr %r16,%r3 /* save dt address in reg16 */
+ li %r4,20
+ LWZX_BE %r6,%r3,%r4 /* fetch __be32 version number at byte 20 */
+ cmpwi %cr0,%r6,2 /* v2 or later? */
+ blt 1f
+ li %r4,28
+ STWX_BE %r17,%r3,%r4 /* Store my cpu as __be32 at byte 28 */
+1:
+ /* load the kernel address */
+ ld %r4,(kernel - 0b)(%r18)
+
+ /* load the run_at_load flag */
+ /* possibly patched by kexec */
+ ld %r6,(run_at_load - 0b)(%r18)
+ /* and patch it into the kernel */
+ stw %r6,(0x5c)(%r4)
+
+ mr %r3,%r16 /* restore dt address */
+
+ li %r5,0 /* r5 will be 0 for kernel */
+
+ mfmsr %r11
+ andi. %r10,%r11,1 /* test MSR_LE */
+ bne .Little_endian
+
+ mtctr %r4 /* prepare branch to */
+ bctr /* start kernel */
+
+.Little_endian:
+ mtsrr0 %r4 /* prepare branch to */
+
+ clrrdi %r11,%r11,1 /* clear MSR_LE */
+ mtsrr1 %r11
+
+ rfid /* update MSR and start kernel */
+
+
+ .balign 8
+ .globl kernel
+kernel:
+ .8byte 0x0
+ .size kernel, . - kernel
+
+ .balign 8
+ .globl dt_offset
+dt_offset:
+ .8byte 0x0
+ .size dt_offset, . - dt_offset
+
+
+ .data
+ .balign 8
+.globl purgatory_sha256_digest
+purgatory_sha256_digest:
+ .skip 32
+ .size purgatory_sha256_digest, . - purgatory_sha256_digest
+
+ .balign 8
+.globl purgatory_sha_regions
+purgatory_sha_regions:
+ .skip 8 * 2 * 16
+ .size purgatory_sha_regions, . - purgatory_sha_regions
^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v2 03/12] powerpc/kexec_file: add helper functions for getting memory ranges
2020-07-02 19:53 [PATCH v2 00/12] ppc64: enable kdump support for kexec_file_load syscall Hari Bathini
2020-07-02 19:54 ` [PATCH v2 01/12] kexec_file: allow archs to handle special regions while locating memory hole Hari Bathini
2020-07-02 19:54 ` [PATCH v2 02/12] powerpc/kexec_file: mark PPC64 specific code Hari Bathini
@ 2020-07-02 19:54 ` Hari Bathini
2020-07-02 19:55 ` [PATCH v2 04/12] ppc64/kexec_file: avoid stomping memory used by special regions Hari Bathini
` (9 subsequent siblings)
12 siblings, 0 replies; 16+ messages in thread
From: Hari Bathini @ 2020-07-02 19:54 UTC (permalink / raw)
To: Michael Ellerman, Andrew Morton
Cc: Pingfan Liu, Kexec-ml, Petr Tesarik, Mahesh J Salgaonkar,
Sourabh Jain, lkml, linuxppc-dev, Mimi Zohar, Vivek Goyal,
Dave Young, Thiago Jung Bauermann, Eric Biederman
In kexec case, the kernel to be loaded uses the same memory layout as
the running kernel. So, passing on the DT of the running kernel would
be good enough.
But in case of kdump, different memory ranges are needed to manage
loading the kdump kernel, booting into it and exporting the elfcore
of the crashing kernel. The ranges are exlude memory ranges, usable
memory ranges, reserved memory ranges and crash memory ranges.
Exclude memory ranges specify the list of memory ranges to avoid while
loading kdump segments. Usable memory ranges list the memory ranges
that could be used for booting kdump kernel. Reserved memory ranges
list the memory regions for the loading kernel's reserve map. Crash
memory ranges list the memory ranges to be exported as the crashing
kernel's elfcore.
Add helper functions for setting up the above mentioned memory ranges.
This helpers facilitate in understanding the subsequent changes better
and make it easy to setup the different memory ranges listed above, as
and when appropriate.
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
---
Changes in v2:
* Added an option to merge ranges while sorting to minimize reallocations
for memory ranges list.
* Dropped within_crashkernel option for add_opal_mem_range() &
add_rtas_mem_range() as it is not really needed.
arch/powerpc/include/asm/kexec_ranges.h | 18 +
arch/powerpc/kexec/Makefile | 2
arch/powerpc/kexec/ranges.c | 397 +++++++++++++++++++++++++++++++
3 files changed, 416 insertions(+), 1 deletion(-)
create mode 100644 arch/powerpc/include/asm/kexec_ranges.h
create mode 100644 arch/powerpc/kexec/ranges.c
diff --git a/arch/powerpc/include/asm/kexec_ranges.h b/arch/powerpc/include/asm/kexec_ranges.h
new file mode 100644
index 0000000..799dc40
--- /dev/null
+++ b/arch/powerpc/include/asm/kexec_ranges.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef _ASM_POWERPC_KEXEC_RANGES_H
+#define _ASM_POWERPC_KEXEC_RANGES_H
+
+#define MEM_RANGE_CHUNK_SZ 2048 /* Memory ranges size chunk */
+
+struct crash_mem *realloc_mem_ranges(struct crash_mem **mem_ranges);
+int add_mem_range(struct crash_mem **mem_ranges, u64 base, u64 size);
+int add_tce_mem_ranges(struct crash_mem **mem_ranges);
+int add_initrd_mem_range(struct crash_mem **mem_ranges);
+int add_htab_mem_range(struct crash_mem **mem_ranges);
+int add_kernel_mem_range(struct crash_mem **mem_ranges);
+int add_rtas_mem_range(struct crash_mem **mem_ranges);
+int add_opal_mem_range(struct crash_mem **mem_ranges);
+int add_reserved_ranges(struct crash_mem **mem_ranges);
+void sort_memory_ranges(struct crash_mem *mrngs, bool merge);
+
+#endif /* _ASM_POWERPC_KEXEC_RANGES_H */
diff --git a/arch/powerpc/kexec/Makefile b/arch/powerpc/kexec/Makefile
index 67c3553..4aff684 100644
--- a/arch/powerpc/kexec/Makefile
+++ b/arch/powerpc/kexec/Makefile
@@ -7,7 +7,7 @@ obj-y += core.o crash.o core_$(BITS).o
obj-$(CONFIG_PPC32) += relocate_32.o
-obj-$(CONFIG_KEXEC_FILE) += file_load.o file_load_$(BITS).o elf_$(BITS).o
+obj-$(CONFIG_KEXEC_FILE) += file_load.o ranges.o file_load_$(BITS).o elf_$(BITS).o
ifdef CONFIG_HAVE_IMA_KEXEC
ifdef CONFIG_IMA
diff --git a/arch/powerpc/kexec/ranges.c b/arch/powerpc/kexec/ranges.c
new file mode 100644
index 0000000..a704819
--- /dev/null
+++ b/arch/powerpc/kexec/ranges.c
@@ -0,0 +1,397 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * powerpc code to implement the kexec_file_load syscall
+ *
+ * Copyright (C) 2004 Adam Litke (agl@us.ibm.com)
+ * Copyright (C) 2004 IBM Corp.
+ * Copyright (C) 2004,2005 Milton D Miller II, IBM Corporation
+ * Copyright (C) 2005 R Sharada (sharada@in.ibm.com)
+ * Copyright (C) 2006 Mohan Kumar M (mohan@in.ibm.com)
+ * Copyright (C) 2020 IBM Corporation
+ *
+ * Based on kexec-tools' kexec-ppc64.c, fs2dt.c.
+ * Heavily modified for the kernel by
+ * Hari Bathini <hbathini@linux.ibm.com>.
+ */
+
+#include <linux/kexec.h>
+#include <linux/of_device.h>
+#include <linux/slab.h>
+#include <asm/sections.h>
+#include <asm/kexec_ranges.h>
+
+/**
+ * get_max_nr_ranges - Get the max no. of ranges crash_mem structure
+ * could hold, given the size allocated for it.
+ * @size: Allocation size of crash_mem structure.
+ *
+ * Returns the maximum no. of ranges.
+ */
+static inline unsigned int get_max_nr_ranges(size_t size)
+{
+ return ((size - sizeof(struct crash_mem)) /
+ sizeof(struct crash_mem_range));
+}
+
+/**
+ * get_mem_rngs_size - Get the allocated size of mrngs based on
+ * max_nr_ranges and chunk size.
+ * @mrngs: Memory ranges.
+ *
+ * Returns the maximum no. of ranges.
+ */
+static inline size_t get_mem_rngs_size(struct crash_mem *mrngs)
+{
+ size_t size;
+
+ if (!mrngs)
+ return 0;
+
+ size = (sizeof(struct crash_mem) +
+ (mrngs->max_nr_ranges * sizeof(struct crash_mem_range)));
+
+ /*
+ * Memory is allocated in size multiple of MEM_RANGE_CHUNK_SZ.
+ * So, align to get the actual length.
+ */
+ return ALIGN(size, MEM_RANGE_CHUNK_SZ);
+}
+
+/**
+ * __add_mem_range - add a memory range to memory ranges list.
+ * @mem_ranges: Range list to add the memory range to.
+ * @base: Base address of the range to add.
+ * @size: Size of the memory range to add.
+ *
+ * (Re)allocates memory, if needed.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+static int __add_mem_range(struct crash_mem **mem_ranges, u64 base, u64 size)
+{
+ struct crash_mem *mrngs = *mem_ranges;
+
+ if ((mrngs == NULL) || (mrngs->nr_ranges == mrngs->max_nr_ranges)) {
+ mrngs = realloc_mem_ranges(mem_ranges);
+ if (!mrngs)
+ return -ENOMEM;
+ }
+
+ mrngs->ranges[mrngs->nr_ranges].start = base;
+ mrngs->ranges[mrngs->nr_ranges].end = base + size - 1;
+ mrngs->nr_ranges++;
+ return 0;
+}
+
+/**
+ * __merge_memory_ranges - Merges the given memory ranges list.
+ * @mem_ranges: Range list to merge.
+ *
+ * Assumes a sorted range list.
+ *
+ * Returns nothing.
+ */
+static void __merge_memory_ranges(struct crash_mem *mrngs)
+{
+ struct crash_mem_range *rngs;
+ int i, idx;
+
+ if (!mrngs)
+ return;
+
+ idx = 0;
+ rngs = &mrngs->ranges[0];
+ for (i = 1; i < mrngs->nr_ranges; i++) {
+ if (rngs[i].start <= (rngs[i-1].end + 1))
+ rngs[idx].end = rngs[i].end;
+ else {
+ idx++;
+ if (i == idx)
+ continue;
+
+ rngs[idx] = rngs[i];
+ }
+ }
+ mrngs->nr_ranges = idx + 1;
+}
+
+/**
+ * realloc_mem_ranges - reallocate mem_ranges with size incremented
+ * by MEM_RANGE_CHUNK_SZ. Frees up the old memory,
+ * if memory allocation fails.
+ * @mem_ranges: Memory ranges to reallocate.
+ *
+ * Returns pointer to reallocated memory on success, NULL otherwise.
+ */
+struct crash_mem *realloc_mem_ranges(struct crash_mem **mem_ranges)
+{
+ struct crash_mem *mrngs = *mem_ranges;
+ unsigned int nr_ranges;
+ size_t size;
+
+ size = get_mem_rngs_size(mrngs);
+ nr_ranges = mrngs ? mrngs->nr_ranges : 0;
+
+ size += MEM_RANGE_CHUNK_SZ;
+ mrngs = krealloc(*mem_ranges, size, GFP_KERNEL);
+ if (!mrngs) {
+ kfree(*mem_ranges);
+ *mem_ranges = NULL;
+ return NULL;
+ }
+
+ mrngs->nr_ranges = nr_ranges;
+ mrngs->max_nr_ranges = get_max_nr_ranges(size);
+ *mem_ranges = mrngs;
+
+ return mrngs;
+}
+
+/**
+ * add_mem_range - Updates existing memory range, if there is an overlap.
+ * Else, adds a new memory range.
+ * @mem_ranges: Range list to add the memory range to.
+ * @base: Base address of the range to add.
+ * @size: Size of the memory range to add.
+ *
+ * (Re)allocates memory, if needed.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int add_mem_range(struct crash_mem **mem_ranges, u64 base, u64 size)
+{
+ struct crash_mem *mrngs = *mem_ranges;
+ u64 mstart, mend, end;
+ unsigned int i;
+
+ if (!size)
+ return 0;
+
+ end = base + size - 1;
+
+ if ((mrngs == NULL) || (mrngs->nr_ranges == 0))
+ return __add_mem_range(mem_ranges, base, size);
+
+ for (i = 0; i < mrngs->nr_ranges; i++) {
+ mstart = mrngs->ranges[i].start;
+ mend = mrngs->ranges[i].end;
+ if (base < mend && end > mstart) {
+ if (base < mstart)
+ mrngs->ranges[i].start = base;
+ if (end > mend)
+ mrngs->ranges[i].end = end;
+ return 0;
+ }
+ }
+
+ return __add_mem_range(mem_ranges, base, size);
+}
+
+/**
+ * add_tce_mem_ranges - Adds tce-table range to the given memory ranges list.
+ * @mem_ranges: Range list to add the memory range(s) to.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int add_tce_mem_ranges(struct crash_mem **mem_ranges)
+{
+ struct device_node *dn;
+ int ret;
+
+ for_each_node_by_type(dn, "pci") {
+ u64 base;
+ u32 size;
+
+ ret = of_property_read_u64(dn, "linux,tce-base", &base);
+ ret |= of_property_read_u32(dn, "linux,tce-size", &size);
+ if (!ret)
+ continue;
+
+ ret = add_mem_range(mem_ranges, base, size);
+ if (ret)
+ break;
+ }
+
+ return ret;
+}
+
+/**
+ * add_initrd_mem_range - Adds initrd range to the given memory ranges list,
+ * if the initrd was retained.
+ * @mem_ranges: Range list to add the memory range to.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int add_initrd_mem_range(struct crash_mem **mem_ranges)
+{
+ u64 base, end;
+ int ret = 0;
+ char *str;
+
+ /* This range means something only if initrd was retained */
+ str = strstr(saved_command_line, "retain_initrd");
+ if (!str)
+ return 0;
+
+ ret = of_property_read_u64(of_chosen, "linux,initrd-start", &base);
+ ret |= of_property_read_u64(of_chosen, "linux,initrd-end", &end);
+ if (!ret)
+ ret = add_mem_range(mem_ranges, base, end - base + 1);
+ return ret;
+}
+
+/**
+ * add_htab_mem_range - Adds htab range to the given memory ranges list,
+ * if it exists
+ * @mem_ranges: Range list to add the memory range to.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int add_htab_mem_range(struct crash_mem **mem_ranges)
+{
+#ifdef CONFIG_PPC_BOOK3S_64
+ int ret;
+
+ if (!htab_address)
+ return 0;
+
+ ret = add_mem_range(mem_ranges, __pa(htab_address), htab_size_bytes);
+ return ret;
+#else
+ return 0;
+#endif
+}
+
+/**
+ * add_kernel_mem_range - Adds kernel text region to the given
+ * memory ranges list.
+ * @mem_ranges: Range list to add the memory range to.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int add_kernel_mem_range(struct crash_mem **mem_ranges)
+{
+ int ret;
+
+ ret = add_mem_range(mem_ranges, 0, __pa(_end));
+ return ret;
+}
+
+/**
+ * add_rtas_mem_range - Adds RTAS region to the given memory ranges list.
+ * @mem_ranges: Range list to add the memory range to.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int add_rtas_mem_range(struct crash_mem **mem_ranges)
+{
+ struct device_node *dn;
+ int ret = 0;
+
+ dn = of_find_node_by_path("/rtas");
+ if (dn) {
+ u32 base, size;
+
+ ret = of_property_read_u32(dn, "linux,rtas-base", &base);
+ ret |= of_property_read_u32(dn, "rtas-size", &size);
+ if (ret)
+ return ret;
+
+ ret = add_mem_range(mem_ranges, base, size);
+ }
+ return ret;
+}
+
+/**
+ * add_opal_mem_range - Adds OPAL region to the given memory ranges list.
+ * @mem_ranges: Range list to add the memory range to.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int add_opal_mem_range(struct crash_mem **mem_ranges)
+{
+ struct device_node *dn;
+ int ret = 0;
+
+ dn = of_find_node_by_path("/ibm,opal");
+ if (dn) {
+ u64 base, size;
+
+ ret = of_property_read_u64(dn, "opal-base-address", &base);
+ ret |= of_property_read_u64(dn, "opal-runtime-size", &size);
+ if (ret)
+ return ret;
+
+ ret = add_mem_range(mem_ranges, base, size);
+ }
+ return ret;
+}
+
+/**
+ * add_reserved_ranges - Adds "/reserved-ranges" regions exported by f/w
+ * to the given memory ranges list.
+ * @mem_ranges: Range list to add the memory ranges to.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int add_reserved_ranges(struct crash_mem **mem_ranges)
+{
+ int i, len, ret = 0;
+ const __be32 *prop;
+
+ prop = of_get_property(of_root, "reserved-ranges", &len);
+ if (!prop)
+ return 0;
+
+ /*
+ * Each reserved range is an (address,size) pair, 2 cells each,
+ * totalling 4 cells per range.
+ */
+ for (i = 0; i < len / (sizeof(*prop) * 4); i++) {
+ u64 base, size;
+
+ base = of_read_number(prop + (i * 4) + 0, 2);
+ size = of_read_number(prop + (i * 4) + 2, 2);
+
+ ret = add_mem_range(mem_ranges, base, size);
+ if (ret)
+ break;
+ }
+
+ return ret;
+}
+
+/**
+ * sort_memory_ranges - Sorts the given memory ranges list.
+ * @mem_ranges: Range list to sort.
+ * @merge: If true, merge the list after sorting.
+ *
+ * Returns nothing.
+ */
+void sort_memory_ranges(struct crash_mem *mrngs, bool merge)
+{
+ struct crash_mem_range *rngs;
+ struct crash_mem_range rng;
+ int i, j, idx;
+
+ if (!mrngs)
+ return;
+
+ /* Sort the ranges in-place */
+ rngs = &mrngs->ranges[0];
+ for (i = 0; i < mrngs->nr_ranges; i++) {
+ idx = i;
+ for (j = (i + 1); j < mrngs->nr_ranges; j++) {
+ if (rngs[idx].start > rngs[j].start)
+ idx = j;
+ }
+ if (idx != i) {
+ rng = rngs[idx];
+ rngs[idx] = rngs[i];
+ rngs[i] = rng;
+ }
+ }
+
+ if (merge)
+ __merge_memory_ranges(mrngs);
+}
^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v2 04/12] ppc64/kexec_file: avoid stomping memory used by special regions
2020-07-02 19:53 [PATCH v2 00/12] ppc64: enable kdump support for kexec_file_load syscall Hari Bathini
` (2 preceding siblings ...)
2020-07-02 19:54 ` [PATCH v2 03/12] powerpc/kexec_file: add helper functions for getting memory ranges Hari Bathini
@ 2020-07-02 19:55 ` Hari Bathini
2020-07-02 19:55 ` [PATCH v2 05/12] powerpc/drmem: make lmb walk a bit more flexible Hari Bathini
` (8 subsequent siblings)
12 siblings, 0 replies; 16+ messages in thread
From: Hari Bathini @ 2020-07-02 19:55 UTC (permalink / raw)
To: Michael Ellerman, Andrew Morton
Cc: Pingfan Liu, Kexec-ml, Petr Tesarik, Mahesh J Salgaonkar,
Sourabh Jain, lkml, linuxppc-dev, Mimi Zohar, Vivek Goyal,
Dave Young, Thiago Jung Bauermann, Eric Biederman
crashkernel region could have an overlap with special memory regions
like opal, rtas, tce-table & such. These regions are referred to as
exclude memory ranges. Setup this ranges during image probe in order
to avoid them while finding the buffer for different kdump segments.
Override arch_kexec_locate_mem_hole() to locate a memory hole taking
these ranges into account.
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
---
Changes in v2:
* Did arch_kexec_locate_mem_hole() override to handle special regions.
* Ensured holes in the memory are accounted for while locating mem hole.
* Updated add_rtas_mem_range() & add_opal_mem_range() callsites based on
the new prototype for these functions.
arch/powerpc/include/asm/crashdump-ppc64.h | 10 +
arch/powerpc/include/asm/kexec.h | 7 -
arch/powerpc/kexec/elf_64.c | 7 +
arch/powerpc/kexec/file_load_64.c | 324 ++++++++++++++++++++++++++++
4 files changed, 344 insertions(+), 4 deletions(-)
create mode 100644 arch/powerpc/include/asm/crashdump-ppc64.h
diff --git a/arch/powerpc/include/asm/crashdump-ppc64.h b/arch/powerpc/include/asm/crashdump-ppc64.h
new file mode 100644
index 0000000..90deb46
--- /dev/null
+++ b/arch/powerpc/include/asm/crashdump-ppc64.h
@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef _ASM_POWERPC_CRASHDUMP_PPC64_H
+#define _ASM_POWERPC_CRASHDUMP_PPC64_H
+
+/* min & max addresses for kdump load segments */
+#define KDUMP_BUF_MIN (crashk_res.start)
+#define KDUMP_BUF_MAX ((crashk_res.end < ppc64_rma_size) ? \
+ crashk_res.end : (ppc64_rma_size - 1))
+
+#endif /* __ASM_POWERPC_CRASHDUMP_PPC64_H */
diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
index 7008ea1..bf47a01 100644
--- a/arch/powerpc/include/asm/kexec.h
+++ b/arch/powerpc/include/asm/kexec.h
@@ -100,14 +100,16 @@ void relocate_new_kernel(unsigned long indirection_page, unsigned long reboot_co
#ifdef CONFIG_KEXEC_FILE
extern const struct kexec_file_ops kexec_elf64_ops;
-#ifdef CONFIG_IMA_KEXEC
#define ARCH_HAS_KIMAGE_ARCH
struct kimage_arch {
+ struct crash_mem *exclude_ranges;
+
+#ifdef CONFIG_IMA_KEXEC
phys_addr_t ima_buffer_addr;
size_t ima_buffer_size;
-};
#endif
+};
int setup_purgatory(struct kimage *image, const void *slave_code,
const void *fdt, unsigned long kernel_load_addr,
@@ -125,6 +127,7 @@ int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
unsigned long initrd_load_addr,
unsigned long initrd_len, const char *cmdline);
#endif /* CONFIG_PPC64 */
+
#endif /* CONFIG_KEXEC_FILE */
#else /* !CONFIG_KEXEC_CORE */
diff --git a/arch/powerpc/kexec/elf_64.c b/arch/powerpc/kexec/elf_64.c
index 23ad04c..c695f94 100644
--- a/arch/powerpc/kexec/elf_64.c
+++ b/arch/powerpc/kexec/elf_64.c
@@ -22,6 +22,7 @@
#include <linux/of_fdt.h>
#include <linux/slab.h>
#include <linux/types.h>
+#include <asm/crashdump-ppc64.h>
static void *elf64_load(struct kimage *image, char *kernel_buf,
unsigned long kernel_len, char *initrd,
@@ -46,6 +47,12 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
if (ret)
goto out;
+ if (image->type == KEXEC_TYPE_CRASH) {
+ /* min & max buffer values for kdump case */
+ kbuf.buf_min = pbuf.buf_min = KDUMP_BUF_MIN;
+ kbuf.buf_max = pbuf.buf_max = KDUMP_BUF_MAX;
+ }
+
ret = kexec_elf_load(image, &ehdr, &elf_info, &kbuf, &kernel_load_addr);
if (ret)
goto out;
diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
index e6bff960..932e0e5 100644
--- a/arch/powerpc/kexec/file_load_64.c
+++ b/arch/powerpc/kexec/file_load_64.c
@@ -17,6 +17,9 @@
#include <linux/kexec.h>
#include <linux/of_fdt.h>
#include <linux/libfdt.h>
+#include <linux/memblock.h>
+#include <asm/kexec_ranges.h>
+#include <asm/crashdump-ppc64.h>
const struct kexec_file_ops * const kexec_file_loaders[] = {
&kexec_elf64_ops,
@@ -24,6 +27,240 @@ const struct kexec_file_ops * const kexec_file_loaders[] = {
};
/**
+ * get_exclude_memory_ranges - Get exclude memory ranges. This list includes
+ * regions like opal/rtas, tce-table, initrd,
+ * kernel, htab which should be avoided while
+ * setting up kexec load segments.
+ * @mem_ranges: Range list to add the memory ranges to.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+static int get_exclude_memory_ranges(struct crash_mem **mem_ranges)
+{
+ int ret;
+
+ ret = add_tce_mem_ranges(mem_ranges);
+ if (ret)
+ goto out;
+
+ ret = add_initrd_mem_range(mem_ranges);
+ if (ret)
+ goto out;
+
+ ret = add_htab_mem_range(mem_ranges);
+ if (ret)
+ goto out;
+
+ ret = add_kernel_mem_range(mem_ranges);
+ if (ret)
+ goto out;
+
+ ret = add_rtas_mem_range(mem_ranges);
+ if (ret)
+ goto out;
+
+ ret = add_opal_mem_range(mem_ranges);
+ if (ret)
+ goto out;
+
+ ret = add_reserved_ranges(mem_ranges);
+ if (ret)
+ goto out;
+
+ /* exclude memory ranges should be sorted for easy lookup */
+ sort_memory_ranges(*mem_ranges, true);
+out:
+ if (ret)
+ pr_err("Failed to setup exclude memory ranges\n");
+ return ret;
+}
+
+/**
+ * __locate_mem_hole_top_down - Looks top down for a large enough memory hole
+ * in the memory regions between buf_min & buf_max
+ * for the buffer. If found, sets kbuf->mem.
+ * @kbuf: Buffer contents and memory parameters.
+ * @buf_min: Minimum address for the buffer.
+ * @buf_max: Maximum address for the buffer.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+static int __locate_mem_hole_top_down(struct kexec_buf *kbuf,
+ u64 buf_min, u64 buf_max)
+{
+ int ret = -EADDRNOTAVAIL;
+ phys_addr_t start, end;
+ u64 i;
+
+ for_each_mem_range_rev(i, &memblock.memory, NULL, NUMA_NO_NODE,
+ MEMBLOCK_NONE, &start, &end, NULL) {
+ if (start > buf_max)
+ continue;
+
+ /* Memory hole not found */
+ if (end < buf_min)
+ break;
+
+ /* Adjust memory region based on the given range */
+ if (start < buf_min)
+ start = buf_min;
+ if (end > buf_max)
+ end = buf_max;
+
+ start = ALIGN(start, kbuf->buf_align);
+ if (start < end && (end - start + 1) >= kbuf->memsz) {
+ /* Suitable memory range found. Set kbuf->mem */
+ kbuf->mem = ALIGN_DOWN(end - kbuf->memsz + 1,
+ kbuf->buf_align);
+ ret = 0;
+ break;
+ }
+ }
+
+ return ret;
+}
+
+/**
+ * locate_mem_hole_top_down_ppc64 - Skip special memory regions to find a
+ * suitable buffer with top down approach.
+ * @kbuf: Buffer contents and memory parameters.
+ * @buf_min: Minimum address for the buffer.
+ * @buf_max: Maximum address for the buffer.
+ * @emem: Exclude memory ranges.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+static int locate_mem_hole_top_down_ppc64(struct kexec_buf *kbuf,
+ u64 buf_min, u64 buf_max,
+ const struct crash_mem *emem)
+{
+ int i, ret = 0, err = -EADDRNOTAVAIL;
+ u64 start, end, tmin, tmax;
+
+ tmax = buf_max;
+ for (i = (emem->nr_ranges - 1); i >= 0; i--) {
+ start = emem->ranges[i].start;
+ end = emem->ranges[i].end;
+
+ if (start > tmax)
+ continue;
+
+ if (end < tmax) {
+ tmin = (end < buf_min ? buf_min : end + 1);
+ ret = __locate_mem_hole_top_down(kbuf, tmin, tmax);
+ if (!ret)
+ return 0;
+ }
+
+ tmax = start - 1;
+
+ if (tmax < buf_min) {
+ ret = err;
+ break;
+ }
+ ret = 0;
+ }
+
+ if (!ret) {
+ tmin = buf_min;
+ ret = __locate_mem_hole_top_down(kbuf, tmin, tmax);
+ }
+ return ret;
+}
+
+/**
+ * __locate_mem_hole_bottom_up - Looks bottom up for a large enough memory hole
+ * in the memory regions between buf_min & buf_max
+ * for the buffer. If found, sets kbuf->mem.
+ * @kbuf: Buffer contents and memory parameters.
+ * @buf_min: Minimum address for the buffer.
+ * @buf_max: Maximum address for the buffer.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+static int __locate_mem_hole_bottom_up(struct kexec_buf *kbuf,
+ u64 buf_min, u64 buf_max)
+{
+ int ret = -EADDRNOTAVAIL;
+ phys_addr_t start, end;
+ u64 i;
+
+ for_each_mem_range(i, &memblock.memory, NULL, NUMA_NO_NODE,
+ MEMBLOCK_NONE, &start, &end, NULL) {
+ if (end < buf_min)
+ continue;
+
+ /* Memory hole not found */
+ if (start > buf_max)
+ break;
+
+ /* Adjust memory region based on the given range */
+ if (start < buf_min)
+ start = buf_min;
+ if (end > buf_max)
+ end = buf_max;
+
+ start = ALIGN(start, kbuf->buf_align);
+ if (start < end && (end - start + 1) >= kbuf->memsz) {
+ /* Suitable memory range found. Set kbuf->mem */
+ kbuf->mem = start;
+ ret = 0;
+ break;
+ }
+ }
+
+ return ret;
+}
+
+/**
+ * locate_mem_hole_bottom_up_ppc64 - Skip special memory regions to find a
+ * suitable buffer with bottom up approach.
+ * @kbuf: Buffer contents and memory parameters.
+ * @buf_min: Minimum address for the buffer.
+ * @buf_max: Maximum address for the buffer.
+ * @emem: Exclude memory ranges.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+static int locate_mem_hole_bottom_up_ppc64(struct kexec_buf *kbuf,
+ u64 buf_min, u64 buf_max,
+ const struct crash_mem *emem)
+{
+ int i, ret = 0, err = -EADDRNOTAVAIL;
+ u64 start, end, tmin, tmax;
+
+ tmin = buf_min;
+ for (i = 0; i < emem->nr_ranges; i++) {
+ start = emem->ranges[i].start;
+ end = emem->ranges[i].end;
+
+ if (end < tmin)
+ continue;
+
+ if (start > tmin) {
+ tmax = (start > buf_max ? buf_max : start - 1);
+ ret = __locate_mem_hole_bottom_up(kbuf, tmin, tmax);
+ if (!ret)
+ return 0;
+ }
+
+ tmin = end + 1;
+
+ if (tmin > buf_max) {
+ ret = err;
+ break;
+ }
+ ret = 0;
+ }
+
+ if (!ret) {
+ tmax = buf_max;
+ ret = __locate_mem_hole_bottom_up(kbuf, tmin, tmax);
+ }
+ return ret;
+}
+
+/**
* setup_purgatory_ppc64 - initialize PPC64 specific purgatory's global
* variables and call setup_purgatory() to initialize
* common global variable.
@@ -89,6 +326,67 @@ int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
}
/**
+ * arch_kexec_locate_mem_hole - Skip special memory regions like rtas, opal,
+ * tce-table, reserved-ranges & such (exclude
+ * memory ranges) as they can't be used for kexec
+ * segment buffer. Sets kbuf->mem when a suitable
+ * memory hole is found.
+ * @kbuf: Buffer contents and memory parameters.
+ *
+ * Assumes minimum of PAGE_SIZE alignment for kbuf->memsz & kbuf->buf_align.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf)
+{
+ struct crash_mem **emem;
+ u64 buf_min, buf_max;
+ int ret;
+
+ /*
+ * Use the generic kexec_locate_mem_hole for regular
+ * kexec_file_load syscall
+ */
+ if (kbuf->image->type != KEXEC_TYPE_CRASH)
+ return kexec_locate_mem_hole(kbuf);
+
+ /* Look up the exclude ranges list while locating the memory hole */
+ emem = &(kbuf->image->arch.exclude_ranges);
+ if (!(*emem) || ((*emem)->nr_ranges == 0)) {
+ pr_warn("No exclude range list. Using the default locate mem hole method\n");
+ return 0;
+ }
+
+ /* Segments for kdump kernel should be within crashkernel region */
+ buf_min = (kbuf->buf_min < crashk_res.start ?
+ crashk_res.start : kbuf->buf_min);
+ buf_max = (kbuf->buf_max > crashk_res.end ?
+ crashk_res.end : kbuf->buf_max);
+
+ if (buf_min > buf_max) {
+ pr_err("Invalid buffer min and/or max values\n");
+ return -EINVAL;
+ }
+
+ if (kbuf->top_down)
+ ret = locate_mem_hole_top_down_ppc64(kbuf, buf_min, buf_max,
+ *emem);
+ else
+ ret = locate_mem_hole_bottom_up_ppc64(kbuf, buf_min, buf_max,
+ *emem);
+
+ /* Add the buffer allocated to the exclude list for the next lookup */
+ if (!ret) {
+ add_mem_range(emem, kbuf->mem, kbuf->memsz);
+ sort_memory_ranges(*emem, true);
+ } else {
+ pr_err("Failed to locate memory buffer of size %lu\n",
+ kbuf->memsz);
+ }
+ return ret;
+}
+
+/**
* arch_kexec_kernel_image_probe - Does additional handling needed to setup
* kexec segments.
* @image: kexec image being loaded.
@@ -100,9 +398,31 @@ int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
unsigned long buf_len)
{
- /* We don't support crash kernels yet. */
- if (image->type == KEXEC_TYPE_CRASH)
+ if (image->type == KEXEC_TYPE_CRASH) {
+ int ret;
+
+ /* Get exclude memory ranges needed for setting up kdump segments */
+ ret = get_exclude_memory_ranges(&(image->arch.exclude_ranges));
+ if (ret)
+ pr_err("Failed to setup exclude memory ranges for buffer lookup\n");
+ /* Return this until all changes for panic kernel are in */
return -EOPNOTSUPP;
+ }
return kexec_image_probe_default(image, buf, buf_len);
}
+
+/**
+ * arch_kimage_file_post_load_cleanup - Frees up all the allocations done
+ * while loading the image.
+ * @image: kexec image being loaded.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int arch_kimage_file_post_load_cleanup(struct kimage *image)
+{
+ kfree(image->arch.exclude_ranges);
+ image->arch.exclude_ranges = NULL;
+
+ return kexec_image_post_load_cleanup_default(image);
+}
^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v2 05/12] powerpc/drmem: make lmb walk a bit more flexible
2020-07-02 19:53 [PATCH v2 00/12] ppc64: enable kdump support for kexec_file_load syscall Hari Bathini
` (3 preceding siblings ...)
2020-07-02 19:55 ` [PATCH v2 04/12] ppc64/kexec_file: avoid stomping memory used by special regions Hari Bathini
@ 2020-07-02 19:55 ` Hari Bathini
2020-07-02 19:55 ` [PATCH v2 06/12] ppc64/kexec_file: restrict memory usage of kdump kernel Hari Bathini
` (7 subsequent siblings)
12 siblings, 0 replies; 16+ messages in thread
From: Hari Bathini @ 2020-07-02 19:55 UTC (permalink / raw)
To: Michael Ellerman, Andrew Morton
Cc: Pingfan Liu, Kexec-ml, Petr Tesarik, Mahesh J Salgaonkar,
Sourabh Jain, lkml, linuxppc-dev, Mimi Zohar, Vivek Goyal,
Dave Young, Thiago Jung Bauermann, Eric Biederman
Currently, numa & prom are the users of drmem lmb walk code. Loading
kdump with kexec_file also needs to walk the drmem LMBs to setup the
usable memory ranges for kdump kernel. But there are couple of issues
in using the code as is. One, walk_drmem_lmb() code is built into the
.init section currently, while kexec_file needs it later. Two, there
is no scope to pass data to the callback function for processing and/
or erroring out on certain conditions.
Fix that by, moving drmem LMB walk code out of .init section, adding
scope to pass data to the callback function and bailing out when
an error is encountered in the callback function.
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
---
Changes in v2:
* No changes.
arch/powerpc/include/asm/drmem.h | 9 ++--
arch/powerpc/kernel/prom.c | 13 +++---
arch/powerpc/mm/drmem.c | 87 +++++++++++++++++++++++++-------------
arch/powerpc/mm/numa.c | 13 +++---
4 files changed, 78 insertions(+), 44 deletions(-)
diff --git a/arch/powerpc/include/asm/drmem.h b/arch/powerpc/include/asm/drmem.h
index 414d209..17ccc64 100644
--- a/arch/powerpc/include/asm/drmem.h
+++ b/arch/powerpc/include/asm/drmem.h
@@ -90,13 +90,14 @@ static inline bool drmem_lmb_reserved(struct drmem_lmb *lmb)
}
u64 drmem_lmb_memory_max(void);
-void __init walk_drmem_lmbs(struct device_node *dn,
- void (*func)(struct drmem_lmb *, const __be32 **));
+int walk_drmem_lmbs(struct device_node *dn, void *data,
+ int (*func)(struct drmem_lmb *, const __be32 **, void *));
int drmem_update_dt(void);
#ifdef CONFIG_PPC_PSERIES
-void __init walk_drmem_lmbs_early(unsigned long node,
- void (*func)(struct drmem_lmb *, const __be32 **));
+int __init
+walk_drmem_lmbs_early(unsigned long node, void *data,
+ int (*func)(struct drmem_lmb *, const __be32 **, void *));
#endif
static inline void invalidate_lmb_associativity_index(struct drmem_lmb *lmb)
diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
index 9cc49f2..7df78de 100644
--- a/arch/powerpc/kernel/prom.c
+++ b/arch/powerpc/kernel/prom.c
@@ -468,8 +468,9 @@ static bool validate_mem_limit(u64 base, u64 *size)
* This contains a list of memory blocks along with NUMA affinity
* information.
*/
-static void __init early_init_drmem_lmb(struct drmem_lmb *lmb,
- const __be32 **usm)
+static int __init early_init_drmem_lmb(struct drmem_lmb *lmb,
+ const __be32 **usm,
+ void *data)
{
u64 base, size;
int is_kexec_kdump = 0, rngs;
@@ -484,7 +485,7 @@ static void __init early_init_drmem_lmb(struct drmem_lmb *lmb,
*/
if ((lmb->flags & DRCONF_MEM_RESERVED) ||
!(lmb->flags & DRCONF_MEM_ASSIGNED))
- return;
+ return 0;
if (*usm)
is_kexec_kdump = 1;
@@ -499,7 +500,7 @@ static void __init early_init_drmem_lmb(struct drmem_lmb *lmb,
*/
rngs = dt_mem_next_cell(dt_root_size_cells, usm);
if (!rngs) /* there are no (base, size) duple */
- return;
+ return 0;
}
do {
@@ -524,6 +525,8 @@ static void __init early_init_drmem_lmb(struct drmem_lmb *lmb,
if (lmb->flags & DRCONF_MEM_HOTREMOVABLE)
memblock_mark_hotplug(base, size);
} while (--rngs);
+
+ return 0;
}
#endif /* CONFIG_PPC_PSERIES */
@@ -534,7 +537,7 @@ static int __init early_init_dt_scan_memory_ppc(unsigned long node,
#ifdef CONFIG_PPC_PSERIES
if (depth == 1 &&
strcmp(uname, "ibm,dynamic-reconfiguration-memory") == 0) {
- walk_drmem_lmbs_early(node, early_init_drmem_lmb);
+ walk_drmem_lmbs_early(node, NULL, early_init_drmem_lmb);
return 0;
}
#endif
diff --git a/arch/powerpc/mm/drmem.c b/arch/powerpc/mm/drmem.c
index 59327ce..b2eeea3 100644
--- a/arch/powerpc/mm/drmem.c
+++ b/arch/powerpc/mm/drmem.c
@@ -14,6 +14,8 @@
#include <asm/prom.h>
#include <asm/drmem.h>
+static int n_root_addr_cells, n_root_size_cells;
+
static struct drmem_lmb_info __drmem_info;
struct drmem_lmb_info *drmem_info = &__drmem_info;
@@ -189,12 +191,13 @@ int drmem_update_dt(void)
return rc;
}
-static void __init read_drconf_v1_cell(struct drmem_lmb *lmb,
+static void read_drconf_v1_cell(struct drmem_lmb *lmb,
const __be32 **prop)
{
const __be32 *p = *prop;
- lmb->base_addr = dt_mem_next_cell(dt_root_addr_cells, &p);
+ lmb->base_addr = of_read_number(p, n_root_addr_cells);
+ p += n_root_addr_cells;
lmb->drc_index = of_read_number(p++, 1);
p++; /* skip reserved field */
@@ -205,29 +208,33 @@ static void __init read_drconf_v1_cell(struct drmem_lmb *lmb,
*prop = p;
}
-static void __init __walk_drmem_v1_lmbs(const __be32 *prop, const __be32 *usm,
- void (*func)(struct drmem_lmb *, const __be32 **))
+static int
+__walk_drmem_v1_lmbs(const __be32 *prop, const __be32 *usm, void *data,
+ int (*func)(struct drmem_lmb *, const __be32 **, void *))
{
struct drmem_lmb lmb;
u32 i, n_lmbs;
+ int ret = 0;
n_lmbs = of_read_number(prop++, 1);
- if (n_lmbs == 0)
- return;
-
for (i = 0; i < n_lmbs; i++) {
read_drconf_v1_cell(&lmb, &prop);
- func(&lmb, &usm);
+ ret = func(&lmb, &usm, data);
+ if (ret)
+ break;
}
+
+ return ret;
}
-static void __init read_drconf_v2_cell(struct of_drconf_cell_v2 *dr_cell,
+static void read_drconf_v2_cell(struct of_drconf_cell_v2 *dr_cell,
const __be32 **prop)
{
const __be32 *p = *prop;
dr_cell->seq_lmbs = of_read_number(p++, 1);
- dr_cell->base_addr = dt_mem_next_cell(dt_root_addr_cells, &p);
+ dr_cell->base_addr = of_read_number(p, n_root_addr_cells);
+ p += n_root_addr_cells;
dr_cell->drc_index = of_read_number(p++, 1);
dr_cell->aa_index = of_read_number(p++, 1);
dr_cell->flags = of_read_number(p++, 1);
@@ -235,17 +242,16 @@ static void __init read_drconf_v2_cell(struct of_drconf_cell_v2 *dr_cell,
*prop = p;
}
-static void __init __walk_drmem_v2_lmbs(const __be32 *prop, const __be32 *usm,
- void (*func)(struct drmem_lmb *, const __be32 **))
+static int
+__walk_drmem_v2_lmbs(const __be32 *prop, const __be32 *usm, void *data,
+ int (*func)(struct drmem_lmb *, const __be32 **, void *))
{
struct of_drconf_cell_v2 dr_cell;
struct drmem_lmb lmb;
u32 i, j, lmb_sets;
+ int ret = 0;
lmb_sets = of_read_number(prop++, 1);
- if (lmb_sets == 0)
- return;
-
for (i = 0; i < lmb_sets; i++) {
read_drconf_v2_cell(&dr_cell, &prop);
@@ -259,21 +265,29 @@ static void __init __walk_drmem_v2_lmbs(const __be32 *prop, const __be32 *usm,
lmb.aa_index = dr_cell.aa_index;
lmb.flags = dr_cell.flags;
- func(&lmb, &usm);
+ ret = func(&lmb, &usm, data);
+ if (ret)
+ break;
}
}
+
+ return ret;
}
#ifdef CONFIG_PPC_PSERIES
-void __init walk_drmem_lmbs_early(unsigned long node,
- void (*func)(struct drmem_lmb *, const __be32 **))
+int __init walk_drmem_lmbs_early(unsigned long node, void *data,
+ int (*func)(struct drmem_lmb *, const __be32 **, void *))
{
const __be32 *prop, *usm;
- int len;
+ int len, ret = -ENODEV;
prop = of_get_flat_dt_prop(node, "ibm,lmb-size", &len);
if (!prop || len < dt_root_size_cells * sizeof(__be32))
- return;
+ return ret;
+
+ /* Get the address & size cells */
+ n_root_addr_cells = dt_root_addr_cells;
+ n_root_size_cells = dt_root_size_cells;
drmem_info->lmb_size = dt_mem_next_cell(dt_root_size_cells, &prop);
@@ -281,20 +295,21 @@ void __init walk_drmem_lmbs_early(unsigned long node,
prop = of_get_flat_dt_prop(node, "ibm,dynamic-memory", &len);
if (prop) {
- __walk_drmem_v1_lmbs(prop, usm, func);
+ ret = __walk_drmem_v1_lmbs(prop, usm, data, func);
} else {
prop = of_get_flat_dt_prop(node, "ibm,dynamic-memory-v2",
&len);
if (prop)
- __walk_drmem_v2_lmbs(prop, usm, func);
+ ret = __walk_drmem_v2_lmbs(prop, usm, data, func);
}
memblock_dump_all();
+ return ret;
}
#endif
-static int __init init_drmem_lmb_size(struct device_node *dn)
+static int init_drmem_lmb_size(struct device_node *dn)
{
const __be32 *prop;
int len;
@@ -303,12 +318,12 @@ static int __init init_drmem_lmb_size(struct device_node *dn)
return 0;
prop = of_get_property(dn, "ibm,lmb-size", &len);
- if (!prop || len < dt_root_size_cells * sizeof(__be32)) {
+ if (!prop || len < n_root_size_cells * sizeof(__be32)) {
pr_info("Could not determine LMB size\n");
return -1;
}
- drmem_info->lmb_size = dt_mem_next_cell(dt_root_size_cells, &prop);
+ drmem_info->lmb_size = of_read_number(prop, n_root_size_cells);
return 0;
}
@@ -329,24 +344,36 @@ static const __be32 *of_get_usable_memory(struct device_node *dn)
return prop;
}
-void __init walk_drmem_lmbs(struct device_node *dn,
- void (*func)(struct drmem_lmb *, const __be32 **))
+int walk_drmem_lmbs(struct device_node *dn, void *data,
+ int (*func)(struct drmem_lmb *, const __be32 **, void *))
{
const __be32 *prop, *usm;
+ int ret = -ENODEV;
+
+ if (!of_root)
+ return ret;
+
+ /* Get the address & size cells */
+ of_node_get(of_root);
+ n_root_addr_cells = of_n_addr_cells(of_root);
+ n_root_size_cells = of_n_size_cells(of_root);
+ of_node_put(of_root);
if (init_drmem_lmb_size(dn))
- return;
+ return ret;
usm = of_get_usable_memory(dn);
prop = of_get_property(dn, "ibm,dynamic-memory", NULL);
if (prop) {
- __walk_drmem_v1_lmbs(prop, usm, func);
+ ret = __walk_drmem_v1_lmbs(prop, usm, data, func);
} else {
prop = of_get_property(dn, "ibm,dynamic-memory-v2", NULL);
if (prop)
- __walk_drmem_v2_lmbs(prop, usm, func);
+ ret = __walk_drmem_v2_lmbs(prop, usm, data, func);
}
+
+ return ret;
}
static void __init init_drmem_v1_lmbs(const __be32 *prop)
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index 9fcf2d1..88eb689 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -644,8 +644,9 @@ static inline int __init read_usm_ranges(const __be32 **usm)
* Extract NUMA information from the ibm,dynamic-reconfiguration-memory
* node. This assumes n_mem_{addr,size}_cells have been set.
*/
-static void __init numa_setup_drmem_lmb(struct drmem_lmb *lmb,
- const __be32 **usm)
+static int __init numa_setup_drmem_lmb(struct drmem_lmb *lmb,
+ const __be32 **usm,
+ void *data)
{
unsigned int ranges, is_kexec_kdump = 0;
unsigned long base, size, sz;
@@ -657,7 +658,7 @@ static void __init numa_setup_drmem_lmb(struct drmem_lmb *lmb,
*/
if ((lmb->flags & DRCONF_MEM_RESERVED)
|| !(lmb->flags & DRCONF_MEM_ASSIGNED))
- return;
+ return 0;
if (*usm)
is_kexec_kdump = 1;
@@ -669,7 +670,7 @@ static void __init numa_setup_drmem_lmb(struct drmem_lmb *lmb,
if (is_kexec_kdump) {
ranges = read_usm_ranges(usm);
if (!ranges) /* there are no (base, size) duple */
- return;
+ return 0;
}
do {
@@ -686,6 +687,8 @@ static void __init numa_setup_drmem_lmb(struct drmem_lmb *lmb,
if (sz)
memblock_set_node(base, sz, &memblock.memory, nid);
} while (--ranges);
+
+ return 0;
}
static int __init parse_numa_properties(void)
@@ -787,7 +790,7 @@ static int __init parse_numa_properties(void)
*/
memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
if (memory) {
- walk_drmem_lmbs(memory, numa_setup_drmem_lmb);
+ walk_drmem_lmbs(memory, NULL, numa_setup_drmem_lmb);
of_node_put(memory);
}
^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v2 06/12] ppc64/kexec_file: restrict memory usage of kdump kernel
2020-07-02 19:53 [PATCH v2 00/12] ppc64: enable kdump support for kexec_file_load syscall Hari Bathini
` (4 preceding siblings ...)
2020-07-02 19:55 ` [PATCH v2 05/12] powerpc/drmem: make lmb walk a bit more flexible Hari Bathini
@ 2020-07-02 19:55 ` Hari Bathini
2020-07-02 19:55 ` [PATCH v2 07/12] ppc64/kexec_file: add support to relocate purgatory Hari Bathini
` (6 subsequent siblings)
12 siblings, 0 replies; 16+ messages in thread
From: Hari Bathini @ 2020-07-02 19:55 UTC (permalink / raw)
To: Michael Ellerman, Andrew Morton
Cc: Pingfan Liu, Kexec-ml, Petr Tesarik, Mahesh J Salgaonkar,
Sourabh Jain, lkml, linuxppc-dev, Mimi Zohar, Vivek Goyal,
Dave Young, Thiago Jung Bauermann, Eric Biederman
Kdump kernel, used for capturing the kernel core image, is supposed
to use only specific memory regions to avoid corrupting the image to
be captured. The regions are crashkernel range - the memory reserved
explicitly for kdump kernel, memory used for the tce-table, the OPAL
region and RTAS region as applicable. Restrict kdump kernel memory
to use only these regions by setting up usable-memory DT property.
Also, tell the kdump kernel to run at the loaded address by setting
the magic word at 0x5c.
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
---
Changes in v2:
* Fixed off-by-one error while setting up usable-memory properties.
* Updated add_rtas_mem_range() & add_opal_mem_range() callsites based on
the new prototype for these functions.
arch/powerpc/kexec/file_load_64.c | 401 +++++++++++++++++++++++++++++++++++++
1 file changed, 399 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
index 932e0e5..08c71be 100644
--- a/arch/powerpc/kexec/file_load_64.c
+++ b/arch/powerpc/kexec/file_load_64.c
@@ -17,10 +17,22 @@
#include <linux/kexec.h>
#include <linux/of_fdt.h>
#include <linux/libfdt.h>
+#include <linux/of_device.h>
#include <linux/memblock.h>
+#include <linux/slab.h>
+#include <asm/drmem.h>
#include <asm/kexec_ranges.h>
#include <asm/crashdump-ppc64.h>
+struct umem_info {
+ uint64_t *buf; /* data buffer for usable-memory property */
+ uint32_t idx; /* current index */
+ uint32_t size; /* size allocated for the data buffer */
+
+ /* usable memory ranges to look up */
+ const struct crash_mem *umrngs;
+};
+
const struct kexec_file_ops * const kexec_file_loaders[] = {
&kexec_elf64_ops,
NULL
@@ -76,6 +88,38 @@ static int get_exclude_memory_ranges(struct crash_mem **mem_ranges)
}
/**
+ * get_usable_memory_ranges - Get usable memory ranges. This list includes
+ * regions like crashkernel, opal/rtas & tce-table,
+ * that kdump kernel could use.
+ * @mem_ranges: Range list to add the memory ranges to.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+static int get_usable_memory_ranges(struct crash_mem **mem_ranges)
+{
+ int ret;
+
+ /* First memory block & crashkernel region */
+ ret = add_mem_range(mem_ranges, 0, crashk_res.end + 1);
+ if (ret)
+ goto out;
+
+ ret = add_rtas_mem_range(mem_ranges);
+ if (ret)
+ goto out;
+
+ ret = add_opal_mem_range(mem_ranges);
+ if (ret)
+ goto out;
+
+ ret = add_tce_mem_ranges(mem_ranges);
+out:
+ if (ret)
+ pr_err("Failed to setup usable memory ranges\n");
+ return ret;
+}
+
+/**
* __locate_mem_hole_top_down - Looks top down for a large enough memory hole
* in the memory regions between buf_min & buf_max
* for the buffer. If found, sets kbuf->mem.
@@ -261,6 +305,322 @@ static int locate_mem_hole_bottom_up_ppc64(struct kexec_buf *kbuf,
}
/**
+ * check_realloc_usable_mem - Reallocate buffer if it can't accommodate entries
+ * @um_info: Usable memory buffer and ranges info.
+ * @cnt: No. of entries to accommodate.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+static uint64_t *check_realloc_usable_mem(struct umem_info *um_info, int cnt)
+{
+ void *tbuf;
+
+ if (um_info->size >=
+ ((um_info->idx + cnt) * sizeof(*(um_info->buf))))
+ return um_info->buf;
+
+ um_info->size += MEM_RANGE_CHUNK_SZ;
+ tbuf = krealloc(um_info->buf, um_info->size, GFP_KERNEL);
+ if (!tbuf) {
+ um_info->size -= MEM_RANGE_CHUNK_SZ;
+ return NULL;
+ }
+
+ memset(tbuf + um_info->idx, 0, MEM_RANGE_CHUNK_SZ);
+ return tbuf;
+}
+
+/**
+ * add_usable_mem - Add the usable memory ranges within the given memory range
+ * to the buffer
+ * @um_info: Usable memory buffer and ranges info.
+ * @base: Base address of memory range to look for.
+ * @end: End address of memory range to look for.
+ * @cnt: No. of usable memory ranges added to buffer.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+static int add_usable_mem(struct umem_info *um_info, uint64_t base,
+ uint64_t end, int *cnt)
+{
+ uint64_t loc_base, loc_end, *buf;
+ const struct crash_mem *umrngs;
+ int i, add;
+
+ *cnt = 0;
+ umrngs = um_info->umrngs;
+ for (i = 0; i < umrngs->nr_ranges; i++) {
+ add = 0;
+ loc_base = umrngs->ranges[i].start;
+ loc_end = umrngs->ranges[i].end;
+ if (loc_base >= base && loc_end <= end)
+ add = 1;
+ else if (base < loc_end && end > loc_base) {
+ if (loc_base < base)
+ loc_base = base;
+ if (loc_end > end)
+ loc_end = end;
+ add = 1;
+ }
+
+ if (add) {
+ buf = check_realloc_usable_mem(um_info, 2);
+ if (!buf)
+ return -ENOMEM;
+
+ um_info->buf = buf;
+ buf[um_info->idx++] = cpu_to_be64(loc_base);
+ buf[um_info->idx++] =
+ cpu_to_be64(loc_end - loc_base + 1);
+ (*cnt)++;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * kdump_setup_usable_lmb - This is a callback function that gets called by
+ * walk_drmem_lmbs for every LMB to set its
+ * usable memory ranges.
+ * @lmb: LMB info.
+ * @usm: linux,drconf-usable-memory property value.
+ * @data: Pointer to usable memory buffer and ranges info.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+static int kdump_setup_usable_lmb(struct drmem_lmb *lmb, const __be32 **usm,
+ void *data)
+{
+ struct umem_info *um_info;
+ uint64_t base, end, *buf;
+ int cnt, tmp_idx, ret;
+
+ /*
+ * kdump load isn't supported on kernels already booted with
+ * linux,drconf-usable-memory property.
+ */
+ if (*usm) {
+ pr_err("Trying kdump load from a kdump kernel?\n");
+ return -EINVAL;
+ }
+
+ um_info = data;
+ tmp_idx = um_info->idx;
+ buf = check_realloc_usable_mem(um_info, 1);
+ if (!buf)
+ return -ENOMEM;
+
+ um_info->idx++;
+ um_info->buf = buf;
+ base = lmb->base_addr;
+ end = base + drmem_lmb_size() - 1;
+ ret = add_usable_mem(um_info, base, end, &cnt);
+ if (!ret)
+ um_info->buf[tmp_idx] = cpu_to_be64(cnt);
+
+ return ret;
+}
+
+/**
+ * get_node_path - Get the full path of the given node.
+ * @dn: Node.
+ * @path: Updated with the full path of the node.
+ *
+ * Returns nothing.
+ */
+static void get_node_path(struct device_node *dn, char *path)
+{
+ if (!dn)
+ return;
+
+ get_node_path(dn->parent, path);
+ sprintf(path, "/%s", dn->full_name);
+}
+
+/**
+ * get_node_pathlen - Get the full path length of the given node.
+ * @dn: Node.
+ *
+ * Returns the length of the full path of the node.
+ */
+static int get_node_pathlen(struct device_node *dn)
+{
+ int len = 0;
+
+ while (dn) {
+ len += strlen(dn->full_name) + 1;
+ dn = dn->parent;
+ }
+ len++;
+
+ return len;
+}
+
+/**
+ * add_usable_mem_property - Add usable memory property for the given
+ * memory node.
+ * @fdt: Flattened device tree for the kdump kernel.
+ * @dn: Memory node.
+ * @um_info: Usable memory buffer and ranges info.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+static int add_usable_mem_property(void *fdt, struct device_node *dn,
+ struct umem_info *um_info)
+{
+ int n_mem_addr_cells, n_mem_size_cells, node;
+ int i, len, ranges, cnt, ret;
+ uint64_t base, end, *buf;
+ const __be32 *prop;
+ char *pathname;
+
+ /* Allocate memory for node path */
+ pathname = kzalloc(ALIGN(get_node_pathlen(dn), 8), GFP_KERNEL);
+ if (!pathname)
+ return -ENOMEM;
+
+ /* Get the full path of the memory node */
+ get_node_path(dn, pathname);
+ pr_debug("Memory node path: %s\n", pathname);
+
+ /* Now that we know the path, find its offset in kdump kernel's fdt */
+ node = fdt_path_offset(fdt, pathname);
+ if (node < 0) {
+ pr_err("Malformed device tree: error reading %s\n",
+ pathname);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /* Get the address & size cells */
+ n_mem_addr_cells = of_n_addr_cells(dn);
+ n_mem_size_cells = of_n_size_cells(dn);
+ pr_debug("address cells: %d, size cells: %d\n", n_mem_addr_cells,
+ n_mem_size_cells);
+
+ um_info->idx = 0;
+ buf = check_realloc_usable_mem(um_info, 2);
+ if (!buf) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ um_info->buf = buf;
+
+ prop = of_get_property(dn, "reg", &len);
+ if (!prop || len <= 0) {
+ ret = 0;
+ goto out;
+ }
+
+ /*
+ * "reg" property represents sequence of (addr,size) duples
+ * each representing a memory range.
+ */
+ ranges = (len >> 2) / (n_mem_addr_cells + n_mem_size_cells);
+
+ for (i = 0; i < ranges; i++) {
+ base = of_read_number(prop, n_mem_addr_cells);
+ prop += n_mem_addr_cells;
+ end = base + of_read_number(prop, n_mem_size_cells) - 1;
+
+ ret = add_usable_mem(um_info, base, end, &cnt);
+ if (ret) {
+ ret = ret;
+ goto out;
+ }
+ }
+
+ /*
+ * No kdump kernel usable memory found in this memory node.
+ * Write (0,0) duple in linux,usable-memory property for
+ * this region to be ignored.
+ */
+ if (um_info->idx == 0) {
+ um_info->buf[0] = 0;
+ um_info->buf[1] = 0;
+ um_info->idx = 2;
+ }
+
+ ret = fdt_setprop(fdt, node, "linux,usable-memory", um_info->buf,
+ (um_info->idx * sizeof(*(um_info->buf))));
+
+out:
+ kfree(pathname);
+ return ret;
+}
+
+
+/**
+ * update_usable_mem_fdt - Updates kdump kernel's fdt with linux,usable-memory
+ * and linux,drconf-usable-memory DT properties as
+ * appropriate to restrict its memory usage.
+ * @fdt: Flattened device tree for the kdump kernel.
+ * @usable_mem: Usable memory ranges for kdump kernel.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+static int update_usable_mem_fdt(void *fdt, struct crash_mem *usable_mem)
+{
+ struct umem_info um_info;
+ struct device_node *dn;
+ int node, ret = 0;
+
+ if (!usable_mem) {
+ pr_err("Usable memory ranges for kdump kernel not found\n");
+ return -ENOENT;
+ }
+
+ node = fdt_path_offset(fdt, "/ibm,dynamic-reconfiguration-memory");
+ if (node == -FDT_ERR_NOTFOUND)
+ pr_debug("No dynamic reconfiguration memory found\n");
+ else if (node < 0) {
+ pr_err("Malformed device tree: error reading /ibm,dynamic-reconfiguration-memory.\n");
+ return -EINVAL;
+ }
+
+ um_info.size = 0;
+ um_info.idx = 0;
+ um_info.buf = NULL;
+ um_info.umrngs = usable_mem;
+
+ dn = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
+ if (dn) {
+ ret = walk_drmem_lmbs(dn, &um_info, kdump_setup_usable_lmb);
+ of_node_put(dn);
+
+ if (ret)
+ goto out;
+
+ ret = fdt_setprop(fdt, node, "linux,drconf-usable-memory",
+ um_info.buf,
+ (um_info.idx * sizeof(*(um_info.buf))));
+ if (ret) {
+ pr_err("Failed to set linux,drconf-usable-memory property");
+ goto out;
+ }
+ }
+
+ /*
+ * Walk through each memory node and set linux,usable-memory property
+ * for the corresponding node in kdump kernel's fdt.
+ */
+ for_each_node_by_type(dn, "memory") {
+ ret = add_usable_mem_property(fdt, dn, &um_info);
+ if (ret) {
+ pr_err("Failed to set linux,usable-memory property for %s node",
+ dn->full_name);
+ goto out;
+ }
+ }
+
+out:
+ kfree(um_info.buf);
+ return ret;
+}
+
+/**
* setup_purgatory_ppc64 - initialize PPC64 specific purgatory's global
* variables and call setup_purgatory() to initialize
* common global variable.
@@ -281,6 +641,25 @@ int setup_purgatory_ppc64(struct kimage *image, const void *slave_code,
ret = setup_purgatory(image, slave_code, fdt, kernel_load_addr,
fdt_load_addr);
if (ret)
+ goto out;
+
+ if (image->type == KEXEC_TYPE_CRASH) {
+ uint32_t my_run_at_load = 1;
+
+ /*
+ * Tell relocatable kernel to run at load address
+ * via the word meant for that at 0x5c.
+ */
+ ret = kexec_purgatory_get_set_symbol(image, "run_at_load",
+ &my_run_at_load,
+ sizeof(my_run_at_load),
+ false);
+ if (ret)
+ goto out;
+ }
+
+out:
+ if (ret)
pr_err("Failed to setup purgatory symbols");
return ret;
}
@@ -301,6 +680,7 @@ int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
unsigned long initrd_load_addr,
unsigned long initrd_len, const char *cmdline)
{
+ struct crash_mem *umem = NULL;
int chosen_node, ret;
/* Remove memory reservation for the current device tree. */
@@ -313,15 +693,32 @@ int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
return ret;
}
+ /*
+ * Restrict memory usage for kdump kernel by setting up
+ * usable memory ranges.
+ */
+ if (image->type == KEXEC_TYPE_CRASH) {
+ ret = get_usable_memory_ranges(&umem);
+ if (ret)
+ goto out;
+
+ ret = update_usable_mem_fdt(fdt, umem);
+ if (ret) {
+ pr_err("Error setting up usable-memory property for kdump kernel\n");
+ goto out;
+ }
+ }
+
ret = setup_new_fdt(image, fdt, initrd_load_addr, initrd_len,
cmdline, &chosen_node);
if (ret)
- return ret;
+ goto out;
ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
if (ret)
pr_err("Failed to update device-tree with linux,booted-from-kexec\n");
-
+out:
+ kfree(umem);
return ret;
}
^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v2 07/12] ppc64/kexec_file: add support to relocate purgatory
2020-07-02 19:53 [PATCH v2 00/12] ppc64: enable kdump support for kexec_file_load syscall Hari Bathini
` (5 preceding siblings ...)
2020-07-02 19:55 ` [PATCH v2 06/12] ppc64/kexec_file: restrict memory usage of kdump kernel Hari Bathini
@ 2020-07-02 19:55 ` Hari Bathini
2020-07-02 19:56 ` [PATCH v2 08/12] ppc64/kexec_file: setup the stack for purgatory Hari Bathini
` (5 subsequent siblings)
12 siblings, 0 replies; 16+ messages in thread
From: Hari Bathini @ 2020-07-02 19:55 UTC (permalink / raw)
To: Michael Ellerman, Andrew Morton
Cc: kernel test robot, Pingfan Liu, Kexec-ml, Petr Tesarik,
Mahesh J Salgaonkar, Mimi Zohar, lkml, linuxppc-dev,
Sourabh Jain, Vivek Goyal, Dave Young, Thiago Jung Bauermann,
Eric Biederman
Right now purgatory implementation is only minimal. But if purgatory
code is to be enhanced to copy memory to the backup region and verify
sha256 digest, relocations may have to be applied to the purgatory.
So, add support to relocate purgatory in kexec_file_load system call
by setting up TOC pointer and applying RELA relocations as needed.
Reported-by: kernel test robot <lkp@intel.com>
[lkp: In v1, 'struct mem_sym' was declared in parameter list]
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
---
Changes in v2:
* Fixed wrong use of 'struct mem_sym' in local_entry_offset() as
reported by lkp. lkp report for reference:
- https://lore.kernel.org/patchwork/patch/1264421/
arch/powerpc/kexec/file_load_64.c | 338 ++++++++++++++++++++++++++++++++
arch/powerpc/purgatory/trampoline_64.S | 8 +
2 files changed, 346 insertions(+)
diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
index 08c71be..adca9c0 100644
--- a/arch/powerpc/kexec/file_load_64.c
+++ b/arch/powerpc/kexec/file_load_64.c
@@ -20,6 +20,7 @@
#include <linux/of_device.h>
#include <linux/memblock.h>
#include <linux/slab.h>
+#include <asm/types.h>
#include <asm/drmem.h>
#include <asm/kexec_ranges.h>
#include <asm/crashdump-ppc64.h>
@@ -621,6 +622,242 @@ static int update_usable_mem_fdt(void *fdt, struct crash_mem *usable_mem)
}
/**
+ * get_toc_section - Look for ".toc" symbol and return the corresponding section
+ * @ehdr: ELF header.
+ *
+ * Returns TOC section on success, NULL otherwise.
+ */
+static const Elf_Shdr *get_toc_section(const Elf_Ehdr *ehdr)
+{
+ const Elf_Shdr *sechdrs;
+ const char *secstrings;
+ int i;
+
+ if (!ehdr) {
+ pr_err("Purgatory elf load info missing?\n");
+ return NULL;
+ }
+
+ sechdrs = (void *)ehdr + ehdr->e_shoff;
+ secstrings = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
+
+ for (i = 0; i < ehdr->e_shnum; i++) {
+ if ((sechdrs[i].sh_size != 0) &&
+ (strcmp(secstrings + sechdrs[i].sh_name, ".toc") == 0)) {
+ /* Return the ".toc" section */
+ pr_debug("TOC section number is %d\n", i);
+ return &sechdrs[i];
+ }
+ }
+
+ return NULL;
+}
+
+/**
+ * get_toc_ptr - r2 is the TOC pointer: it points 0x8000 into the TOC
+ * @ehdr: ELF header.
+ *
+ * Returns r2 on success, 0 otherwise.
+ */
+static unsigned long get_toc_ptr(const Elf_Ehdr *ehdr)
+{
+ const Elf_Shdr *sechdr;
+
+ sechdr = get_toc_section(ehdr);
+ if (!sechdr) {
+ pr_err("Could not get the TOC section!\n");
+ return 0;
+ }
+
+ return sechdr->sh_addr + 0x8000;
+}
+
+/* Helper functions to apply relocations */
+static int do_relative_toc(unsigned long val, uint16_t *loc,
+ unsigned long mask, int complain_signed)
+{
+ if (complain_signed && (val + 0x8000 > 0xffff)) {
+ pr_err("TOC16 relocation overflows (%lu)\n", val);
+ return -ENOEXEC;
+ }
+
+ if ((~mask & 0xffff) & val) {
+ pr_err("Bad TOC16 relocation (%lu)\n", val);
+ return -ENOEXEC;
+ }
+
+ *loc = (*loc & ~mask) | (val & mask);
+ return 0;
+}
+#ifdef PPC64_ELF_ABI_v2
+/* PowerPC64 specific values for the Elf64_Sym st_other field. */
+#define STO_PPC64_LOCAL_BIT 5
+#define STO_PPC64_LOCAL_MASK (7 << STO_PPC64_LOCAL_BIT)
+#define PPC64_LOCAL_ENTRY_OFFSET(other) \
+ (((1 << (((other) & STO_PPC64_LOCAL_MASK) >> STO_PPC64_LOCAL_BIT)) \
+ >> 2) << 2)
+
+static unsigned int local_entry_offset(const Elf64_Sym *sym)
+{
+ /* If this symbol has a local entry point, use it. */
+ return PPC64_LOCAL_ENTRY_OFFSET(sym->st_other);
+}
+#else
+static unsigned int local_entry_offset(const Elf64_Sym *sym)
+{
+ return 0;
+}
+#endif
+
+/**
+ * kexec_do_relocs_ppc64 - Apply relocations based on relocation type.
+ * @my_r2: TOC pointer.
+ * @sym: Symbol to relocate.
+ * @r_type: Relocation type.
+ * @loc: Location to modify.
+ * @val: Relocated symbol value.
+ * @addr: Final location after relocation.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+static int kexec_do_relocs_ppc64(unsigned long my_r2, const Elf_Sym *sym,
+ int r_type, void *loc, unsigned long val,
+ unsigned long addr)
+{
+ int ret = 0;
+
+ switch (r_type) {
+ case R_PPC64_ADDR32:
+ /* Simply set it */
+ *(uint32_t *)loc = val;
+ break;
+
+ case R_PPC64_ADDR64:
+ /* Simply set it */
+ *(uint64_t *)loc = val;
+ break;
+
+ case R_PPC64_REL64:
+ *(uint64_t *)loc = val - (uint64_t)loc;
+ break;
+
+ case R_PPC64_REL32:
+ /* Convert value to relative */
+ val -= (unsigned long)loc;
+ if (val + 0x80000000 > 0xffffffff) {
+ pr_err("REL32 %li out of range!\n", val);
+ return -ENOEXEC;
+ }
+
+ *(uint32_t *)loc = val;
+ break;
+
+ case R_PPC64_TOC:
+ *(uint64_t *)loc = my_r2;
+ break;
+
+ case R_PPC64_TOC16:
+ ret = do_relative_toc(val - my_r2, loc, 0xffff, 1);
+ break;
+
+ case R_PPC64_TOC16_DS:
+ ret = do_relative_toc(val - my_r2, loc, 0xfffc, 1);
+ break;
+
+ case R_PPC64_TOC16_LO:
+ ret = do_relative_toc(val - my_r2, loc, 0xffff, 0);
+ break;
+
+ case R_PPC64_TOC16_LO_DS:
+ ret = do_relative_toc(val - my_r2, loc, 0xfffc, 0);
+ break;
+
+ case R_PPC64_TOC16_HI:
+ ret = do_relative_toc((val - my_r2) >> 16, loc,
+ 0xffff, 0);
+ break;
+
+ case R_PPC64_TOC16_HA:
+ ret = do_relative_toc((val - my_r2 + 0x8000) >> 16, loc,
+ 0xffff, 0);
+ break;
+
+ case R_PPC64_REL24:
+ val += local_entry_offset(sym);
+ /* Convert value to relative */
+ val -= addr;
+ if (val + 0x2000000 > 0x3ffffff || (val & 3) != 0) {
+ pr_err("REL24 %li out of range!\n", val);
+ return -ENOEXEC;
+ }
+
+ /* Only replace bits 2 through 26 */
+ *(uint32_t *)loc = ((*(uint32_t *)loc & ~0x03fffffc) |
+ (val & 0x03fffffc));
+ break;
+
+ case R_PPC64_ADDR16_LO:
+ *(uint16_t *)loc = val & 0xffff;
+ break;
+
+ case R_PPC64_ADDR16_HI:
+ *(uint16_t *)loc = (val >> 16) & 0xffff;
+ break;
+
+ case R_PPC64_ADDR16_HA:
+ *(uint16_t *)loc = (((val + 0x8000) >> 16) & 0xffff);
+ break;
+
+ case R_PPC64_ADDR16_HIGHER:
+ *(uint16_t *)loc = (((uint64_t)val >> 32) & 0xffff);
+ break;
+
+ case R_PPC64_ADDR16_HIGHEST:
+ *(uint16_t *)loc = (((uint64_t)val >> 48) & 0xffff);
+ break;
+
+ /* R_PPC64_REL16_HA and R_PPC64_REL16_LO are handled to support
+ * ABIv2 r2 assignment based on r12 for PIC executable.
+ * Here address is known, so replace
+ * 0: addis 2,12,.TOC.-0b@ha
+ * addi 2,2,.TOC.-0b@l
+ * by
+ * lis 2,.TOC.@ha
+ * addi 2,2,.TOC.@l
+ */
+ case R_PPC64_REL16_HA:
+ /* check that we are dealing with the addis 2,12 instruction */
+ if (((*(uint32_t *)loc) & 0xffff0000) != 0x3c4c0000) {
+ pr_err("Unexpected instruction for R_PPC64_REL16_HA");
+ return -ENOEXEC;
+ }
+
+ val += my_r2;
+ /* replacing by lis 2 */
+ *(uint32_t *)loc = 0x3c400000 + ((val >> 16) & 0xffff);
+ break;
+
+ case R_PPC64_REL16_LO:
+ /* check that we are dealing with the addi 2,2 instruction */
+ if (((*(uint32_t *)loc) & 0xffff0000) != 0x38420000) {
+ pr_err("Unexpected instruction for R_PPC64_REL16_LO");
+ return -ENOEXEC;
+ }
+
+ val += my_r2 - 4;
+ *(uint16_t *)loc = val & 0xffff;
+ break;
+
+ default:
+ pr_err("Unknown rela relocation: %d\n", r_type);
+ ret = -ENOEXEC;
+ break;
+ }
+
+ return ret;
+}
+
+/**
* setup_purgatory_ppc64 - initialize PPC64 specific purgatory's global
* variables and call setup_purgatory() to initialize
* common global variable.
@@ -636,6 +873,7 @@ int setup_purgatory_ppc64(struct kimage *image, const void *slave_code,
const void *fdt, unsigned long kernel_load_addr,
unsigned long fdt_load_addr)
{
+ uint64_t val;
int ret;
ret = setup_purgatory(image, slave_code, fdt, kernel_load_addr,
@@ -658,6 +896,10 @@ int setup_purgatory_ppc64(struct kimage *image, const void *slave_code,
goto out;
}
+ /* Setup the TOC pointer */
+ val = get_toc_ptr(image->purgatory_info.ehdr);
+ ret = kexec_purgatory_get_set_symbol(image, "my_toc", &val, sizeof(val),
+ false);
out:
if (ret)
pr_err("Failed to setup purgatory symbols");
@@ -784,6 +1026,102 @@ int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf)
}
/**
+ * arch_kexec_apply_relocations_add - Apply relocations of type RELA
+ * @pi: Purgatory Info.
+ * @section: Section relocations applying to.
+ * @relsec: Section containing RELAs.
+ * @symtab: Corresponding symtab.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int arch_kexec_apply_relocations_add(struct purgatory_info *pi,
+ Elf_Shdr *section,
+ const Elf_Shdr *relsec,
+ const Elf_Shdr *symtab)
+{
+ const char *strtab, *name, *shstrtab;
+ const Elf_Shdr *sechdrs;
+ int i, r_type, ret = 0;
+ const Elf_Ehdr *ehdr;
+ unsigned long my_r2;
+ Elf_Rela *relas;
+
+ ehdr = pi->ehdr;
+
+ /* String & section header string table */
+ sechdrs = (void *)ehdr + ehdr->e_shoff;
+ strtab = (char *)ehdr + sechdrs[symtab->sh_link].sh_offset;
+ shstrtab = (char *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
+
+ relas = (void *)ehdr + relsec->sh_offset;
+
+ pr_debug("Applying relocate section %s to %u\n",
+ shstrtab + relsec->sh_name, relsec->sh_info);
+
+ /* Get the TOC pointer (r2) */
+ my_r2 = get_toc_ptr(ehdr);
+ if (!my_r2)
+ return -ENOEXEC;
+
+ for (i = 0; i < relsec->sh_size / sizeof(*relas); i++) {
+ const Elf_Sym *sym; /* symbol to relocate */
+ unsigned long addr; /* final location after relocation */
+ unsigned long val; /* relocated symbol value */
+ void *loc; /* tmp location to modify */
+
+ sym = (void *)ehdr + symtab->sh_offset;
+ sym += ELF64_R_SYM(relas[i].r_info);
+
+ if (sym->st_name)
+ name = strtab + sym->st_name;
+ else
+ name = shstrtab + sechdrs[sym->st_shndx].sh_name;
+
+ pr_debug("Symbol: %s info: %x shndx: %x value=%llx size: %llx\n",
+ name, sym->st_info, sym->st_shndx, sym->st_value,
+ sym->st_size);
+
+ if ((sym->st_shndx == SHN_UNDEF) &&
+ (ELF_ST_TYPE(sym->st_info) != STT_NOTYPE)) {
+ pr_err("Undefined symbol: %s\n", name);
+ return -ENOEXEC;
+ }
+
+ if (sym->st_shndx == SHN_COMMON) {
+ pr_err("symbol '%s' in common section\n", name);
+ return -ENOEXEC;
+ }
+
+ if ((sym->st_shndx >= ehdr->e_shnum) &&
+ (sym->st_shndx != SHN_ABS)) {
+ pr_err("Invalid section %d for symbol %s\n",
+ sym->st_shndx, name);
+ return -ENOEXEC;
+ }
+
+ loc = pi->purgatory_buf;
+ loc += section->sh_offset;
+ loc += relas[i].r_offset;
+
+ val = sym->st_value;
+ if (sym->st_shndx != SHN_ABS)
+ val += pi->sechdrs[sym->st_shndx].sh_addr;
+ val += relas[i].r_addend;
+
+ addr = section->sh_addr + relas[i].r_offset;
+
+ pr_debug("Symbol: %s value=%lx address=%lx\n", name, val, addr);
+
+ r_type = ELF64_R_TYPE(relas[i].r_info);
+ ret = kexec_do_relocs_ppc64(my_r2, sym, r_type, loc, val, addr);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+/**
* arch_kexec_kernel_image_probe - Does additional handling needed to setup
* kexec segments.
* @image: kexec image being loaded.
diff --git a/arch/powerpc/purgatory/trampoline_64.S b/arch/powerpc/purgatory/trampoline_64.S
index a5a83c3..7b4a5f7 100644
--- a/arch/powerpc/purgatory/trampoline_64.S
+++ b/arch/powerpc/purgatory/trampoline_64.S
@@ -51,6 +51,8 @@ master:
bl 0f /* Work out where we're running */
0: mflr %r18
+ ld %r2,(my_toc - 0b)(%r18) /* setup toc */
+
/* load device-tree address */
ld %r3, (dt_offset - 0b)(%r18)
mr %r16,%r3 /* save dt address in reg16 */
@@ -103,6 +105,12 @@ dt_offset:
.size dt_offset, . - dt_offset
+ .balign 8
+ .globl my_toc
+my_toc:
+ .8byte 0x0
+ .size my_toc, . - my_toc
+
.data
.balign 8
.globl purgatory_sha256_digest
^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v2 08/12] ppc64/kexec_file: setup the stack for purgatory
2020-07-02 19:53 [PATCH v2 00/12] ppc64: enable kdump support for kexec_file_load syscall Hari Bathini
` (6 preceding siblings ...)
2020-07-02 19:55 ` [PATCH v2 07/12] ppc64/kexec_file: add support to relocate purgatory Hari Bathini
@ 2020-07-02 19:56 ` Hari Bathini
2020-07-02 19:56 ` [PATCH v2 09/12] ppc64/kexec_file: setup backup region for kdump kernel Hari Bathini
` (4 subsequent siblings)
12 siblings, 0 replies; 16+ messages in thread
From: Hari Bathini @ 2020-07-02 19:56 UTC (permalink / raw)
To: Michael Ellerman, Andrew Morton
Cc: Pingfan Liu, Kexec-ml, Petr Tesarik, Mahesh J Salgaonkar,
Sourabh Jain, lkml, linuxppc-dev, Mimi Zohar, Vivek Goyal,
Dave Young, Thiago Jung Bauermann, Eric Biederman
To avoid any weird errors, the purgatory should run with its own
stack. Set one up by adding the stack buffer to .data section of
the purgatory. Also, setup opal base & entry values in r8 & r9
registers to help early OPAL debugging.
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
---
Changes in v2:
* Setting up opal base & entry values in r8 & r9 for early OPAL debug.
arch/powerpc/include/asm/kexec.h | 4 ++++
arch/powerpc/kexec/file_load_64.c | 29 +++++++++++++++++++++++++++++
arch/powerpc/purgatory/trampoline_64.S | 32 ++++++++++++++++++++++++++++++++
3 files changed, 65 insertions(+)
diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
index bf47a01..e78cd0a 100644
--- a/arch/powerpc/include/asm/kexec.h
+++ b/arch/powerpc/include/asm/kexec.h
@@ -45,6 +45,10 @@
#define KEXEC_ARCH KEXEC_ARCH_PPC
#endif
+#ifdef CONFIG_KEXEC_FILE
+#define KEXEC_PURGATORY_STACK_SIZE 16384 /* 16KB stack size */
+#endif
+
#define KEXEC_STATE_NONE 0
#define KEXEC_STATE_IRQS_OFF 1
#define KEXEC_STATE_REAL_MODE 2
diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
index adca9c0..f06dcf1 100644
--- a/arch/powerpc/kexec/file_load_64.c
+++ b/arch/powerpc/kexec/file_load_64.c
@@ -873,6 +873,8 @@ int setup_purgatory_ppc64(struct kimage *image, const void *slave_code,
const void *fdt, unsigned long kernel_load_addr,
unsigned long fdt_load_addr)
{
+ struct device_node *dn;
+ void *stack_buf;
uint64_t val;
int ret;
@@ -896,10 +898,37 @@ int setup_purgatory_ppc64(struct kimage *image, const void *slave_code,
goto out;
}
+ /* Setup the stack top */
+ stack_buf = kexec_purgatory_get_symbol_addr(image, "stack_buf");
+ if (!stack_buf)
+ goto out;
+
+ val = (u64)stack_buf + KEXEC_PURGATORY_STACK_SIZE;
+ ret = kexec_purgatory_get_set_symbol(image, "stack", &val, sizeof(val),
+ false);
+ if (ret)
+ goto out;
+
/* Setup the TOC pointer */
val = get_toc_ptr(image->purgatory_info.ehdr);
ret = kexec_purgatory_get_set_symbol(image, "my_toc", &val, sizeof(val),
false);
+ if (ret)
+ goto out;
+
+ /* Setup OPAL base & entry values */
+ dn = of_find_node_by_path("/ibm,opal");
+ if (dn) {
+ of_property_read_u64(dn, "opal-base-address", &val);
+ ret = kexec_purgatory_get_set_symbol(image, "opal_base", &val,
+ sizeof(val), false);
+ if (ret)
+ goto out;
+
+ of_property_read_u64(dn, "opal-entry-address", &val);
+ ret = kexec_purgatory_get_set_symbol(image, "opal_entry", &val,
+ sizeof(val), false);
+ }
out:
if (ret)
pr_err("Failed to setup purgatory symbols");
diff --git a/arch/powerpc/purgatory/trampoline_64.S b/arch/powerpc/purgatory/trampoline_64.S
index 7b4a5f7..83e93b7 100644
--- a/arch/powerpc/purgatory/trampoline_64.S
+++ b/arch/powerpc/purgatory/trampoline_64.S
@@ -9,6 +9,7 @@
* Copyright (C) 2013, Anton Blanchard, IBM Corporation
*/
+#include <asm/kexec.h>
#include <asm/asm-compat.h>
.machine ppc64
@@ -53,6 +54,8 @@ master:
ld %r2,(my_toc - 0b)(%r18) /* setup toc */
+ ld %r1,(stack - 0b)(%r18) /* setup stack */
+
/* load device-tree address */
ld %r3, (dt_offset - 0b)(%r18)
mr %r16,%r3 /* save dt address in reg16 */
@@ -63,6 +66,11 @@ master:
li %r4,28
STWX_BE %r17,%r3,%r4 /* Store my cpu as __be32 at byte 28 */
1:
+
+ /* Load opal base and entry values in r8 & r9 respectively */
+ ld %r8,(opal_base - 0b)(%r18)
+ ld %r9,(opal_entry - 0b)(%r18)
+
/* load the kernel address */
ld %r4,(kernel - 0b)(%r18)
@@ -111,6 +119,24 @@ my_toc:
.8byte 0x0
.size my_toc, . - my_toc
+ .balign 8
+ .globl stack
+stack:
+ .8byte 0x0
+ .size stack, . - stack
+
+ .balign 8
+ .globl opal_base
+opal_base:
+ .8byte 0x0
+ .size opal_base, . - opal_base
+
+ .balign 8
+ .globl opal_entry
+opal_entry:
+ .8byte 0x0
+ .size opal_entry, . - opal_entry
+
.data
.balign 8
.globl purgatory_sha256_digest
@@ -123,3 +149,9 @@ purgatory_sha256_digest:
purgatory_sha_regions:
.skip 8 * 2 * 16
.size purgatory_sha_regions, . - purgatory_sha_regions
+
+ .balign 8
+.globl stack_buf
+stack_buf:
+ .skip KEXEC_PURGATORY_STACK_SIZE
+ .size stack_buf, . - stack_buf
^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v2 09/12] ppc64/kexec_file: setup backup region for kdump kernel
2020-07-02 19:53 [PATCH v2 00/12] ppc64: enable kdump support for kexec_file_load syscall Hari Bathini
` (7 preceding siblings ...)
2020-07-02 19:56 ` [PATCH v2 08/12] ppc64/kexec_file: setup the stack for purgatory Hari Bathini
@ 2020-07-02 19:56 ` Hari Bathini
2020-07-02 19:56 ` [PATCH v2 10/12] ppc64/kexec_file: prepare elfcore header for crashing kernel Hari Bathini
` (3 subsequent siblings)
12 siblings, 0 replies; 16+ messages in thread
From: Hari Bathini @ 2020-07-02 19:56 UTC (permalink / raw)
To: Michael Ellerman, Andrew Morton
Cc: kernel test robot, Pingfan Liu, Kexec-ml, Petr Tesarik,
Mahesh J Salgaonkar, Mimi Zohar, lkml, linuxppc-dev,
Sourabh Jain, Vivek Goyal, Dave Young, Thiago Jung Bauermann,
Eric Biederman
Though kdump kernel boots from loaded address, the first 64K bytes
of it is copied down to real 0. So, setup a backup region to copy
the first 64K bytes of crashed kernel, in purgatory, before booting
into kdump kernel. Also, update reserve map with backup region and
crashed kernel's memory to avoid kdump kernel from accidentially
using that memory.
Reported-by: kernel test robot <lkp@intel.com>
[lkp: In v1, purgatory() declaration was missing]
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
---
Changes in v2:
* Check if backup region is available before branching out. This is
to keep `kexec -l -s` flow as before as much as possible. This would
eventually change with more testing and addition of sha256 digest
verification support.
* Fixed missing prototype for purgatory() as reported by lkp.
lkp report for reference:
- https://lore.kernel.org/patchwork/patch/1264423/
arch/powerpc/include/asm/crashdump-ppc64.h | 5 +
arch/powerpc/include/asm/kexec.h | 7 ++
arch/powerpc/include/asm/purgatory.h | 11 +++
arch/powerpc/kexec/elf_64.c | 9 +++
arch/powerpc/kexec/file_load_64.c | 95 ++++++++++++++++++++++++++++
arch/powerpc/purgatory/Makefile | 28 ++++++++
arch/powerpc/purgatory/purgatory_64.c | 36 +++++++++++
arch/powerpc/purgatory/trampoline_64.S | 28 +++++++-
8 files changed, 211 insertions(+), 8 deletions(-)
create mode 100644 arch/powerpc/include/asm/purgatory.h
create mode 100644 arch/powerpc/purgatory/purgatory_64.c
diff --git a/arch/powerpc/include/asm/crashdump-ppc64.h b/arch/powerpc/include/asm/crashdump-ppc64.h
index 90deb46..fcc5fce 100644
--- a/arch/powerpc/include/asm/crashdump-ppc64.h
+++ b/arch/powerpc/include/asm/crashdump-ppc64.h
@@ -2,6 +2,11 @@
#ifndef _ASM_POWERPC_CRASHDUMP_PPC64_H
#define _ASM_POWERPC_CRASHDUMP_PPC64_H
+/* Backup region - first 64K bytes of System RAM. */
+#define BACKUP_SRC_START 0
+#define BACKUP_SRC_END 0xffff
+#define BACKUP_SRC_SIZE (BACKUP_SRC_END - BACKUP_SRC_START + 1)
+
/* min & max addresses for kdump load segments */
#define KDUMP_BUF_MIN (crashk_res.start)
#define KDUMP_BUF_MAX ((crashk_res.end < ppc64_rma_size) ? \
diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
index e78cd0a..037cf2b 100644
--- a/arch/powerpc/include/asm/kexec.h
+++ b/arch/powerpc/include/asm/kexec.h
@@ -109,6 +109,9 @@ extern const struct kexec_file_ops kexec_elf64_ops;
struct kimage_arch {
struct crash_mem *exclude_ranges;
+ unsigned long backup_start;
+ void *backup_buf;
+
#ifdef CONFIG_IMA_KEXEC
phys_addr_t ima_buffer_addr;
size_t ima_buffer_size;
@@ -124,6 +127,10 @@ int setup_new_fdt(const struct kimage *image, void *fdt,
int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size);
#ifdef CONFIG_PPC64
+struct kexec_buf;
+
+int load_crashdump_segments_ppc64(struct kimage *image,
+ struct kexec_buf *kbuf);
int setup_purgatory_ppc64(struct kimage *image, const void *slave_code,
const void *fdt, unsigned long kernel_load_addr,
unsigned long fdt_load_addr);
diff --git a/arch/powerpc/include/asm/purgatory.h b/arch/powerpc/include/asm/purgatory.h
new file mode 100644
index 0000000..076d150
--- /dev/null
+++ b/arch/powerpc/include/asm/purgatory.h
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef _ASM_POWERPC_PURGATORY_H
+#define _ASM_POWERPC_PURGATORY_H
+
+#ifndef __ASSEMBLY__
+#include <linux/purgatory.h>
+
+void purgatory(void);
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ASM_POWERPC_PURGATORY_H */
diff --git a/arch/powerpc/kexec/elf_64.c b/arch/powerpc/kexec/elf_64.c
index c695f94..4838b42 100644
--- a/arch/powerpc/kexec/elf_64.c
+++ b/arch/powerpc/kexec/elf_64.c
@@ -67,6 +67,15 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
pr_debug("Loaded purgatory at 0x%lx\n", pbuf.mem);
+ /* Setup additional segments needed for panic kernel */
+ if (image->type == KEXEC_TYPE_CRASH) {
+ ret = load_crashdump_segments_ppc64(image, &kbuf);
+ if (ret) {
+ pr_err("Failed to load kdump kernel segments\n");
+ goto out;
+ }
+ }
+
if (initrd != NULL) {
kbuf.buffer = initrd;
kbuf.bufsz = kbuf.memsz = initrd_len;
diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
index f06dcf1..f91530e 100644
--- a/arch/powerpc/kexec/file_load_64.c
+++ b/arch/powerpc/kexec/file_load_64.c
@@ -20,6 +20,7 @@
#include <linux/of_device.h>
#include <linux/memblock.h>
#include <linux/slab.h>
+#include <linux/vmalloc.h>
#include <asm/types.h>
#include <asm/drmem.h>
#include <asm/kexec_ranges.h>
@@ -858,6 +859,69 @@ static int kexec_do_relocs_ppc64(unsigned long my_r2, const Elf_Sym *sym,
}
/**
+ * load_backup_segment - Initialize backup segment of crashing kernel.
+ * @image: Kexec image.
+ * @kbuf: Buffer contents and memory parameters.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+static int load_backup_segment(struct kimage *image, struct kexec_buf *kbuf)
+{
+ void *buf;
+ int ret;
+
+ /* Setup a segment for backup region */
+ buf = vzalloc(BACKUP_SRC_SIZE);
+ if (!buf)
+ return -ENOMEM;
+
+ /*
+ * A source buffer has no meaning for backup region as data will
+ * be copied from backup source, after crash, in the purgatory.
+ * But as load segment code doesn't recognize such segments,
+ * setup a dummy source buffer to keep it happy for now.
+ */
+ kbuf->buffer = buf;
+ kbuf->mem = KEXEC_BUF_MEM_UNKNOWN;
+ kbuf->bufsz = kbuf->memsz = BACKUP_SRC_SIZE;
+ kbuf->top_down = false;
+
+ ret = kexec_add_buffer(kbuf);
+ if (ret) {
+ vfree(buf);
+ return ret;
+ }
+
+ image->arch.backup_buf = buf;
+ image->arch.backup_start = kbuf->mem;
+ return 0;
+}
+
+/**
+ * load_crashdump_segments_ppc64 - Initialize the additional segements needed
+ * to load kdump kernel.
+ * @image: Kexec image.
+ * @kbuf: Buffer contents and memory parameters.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int load_crashdump_segments_ppc64(struct kimage *image,
+ struct kexec_buf *kbuf)
+{
+ int ret;
+
+ /* Load backup segment - first 64K bytes of the crashing kernel */
+ ret = load_backup_segment(image, kbuf);
+ if (ret) {
+ pr_err("Failed to load backup segment\n");
+ return ret;
+ }
+ pr_debug("Loaded the backup region at 0x%lx\n", kbuf->mem);
+
+ return 0;
+}
+
+/**
* setup_purgatory_ppc64 - initialize PPC64 specific purgatory's global
* variables and call setup_purgatory() to initialize
* common global variable.
@@ -898,6 +962,14 @@ int setup_purgatory_ppc64(struct kimage *image, const void *slave_code,
goto out;
}
+ /* Tell purgatory where to look for backup region */
+ ret = kexec_purgatory_get_set_symbol(image, "backup_start",
+ &image->arch.backup_start,
+ sizeof(image->arch.backup_start),
+ false);
+ if (ret)
+ goto out;
+
/* Setup the stack top */
stack_buf = kexec_purgatory_get_symbol_addr(image, "stack_buf");
if (!stack_buf)
@@ -966,7 +1038,7 @@ int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
/*
* Restrict memory usage for kdump kernel by setting up
- * usable memory ranges.
+ * usable memory ranges and memory reserve map.
*/
if (image->type == KEXEC_TYPE_CRASH) {
ret = get_usable_memory_ranges(&umem);
@@ -978,6 +1050,24 @@ int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
pr_err("Error setting up usable-memory property for kdump kernel\n");
goto out;
}
+
+ ret = fdt_add_mem_rsv(fdt, BACKUP_SRC_START + BACKUP_SRC_SIZE,
+ crashk_res.start - BACKUP_SRC_SIZE);
+ if (ret) {
+ pr_err("Error reserving crash memory: %s\n",
+ fdt_strerror(ret));
+ goto out;
+ }
+ }
+
+ if (image->arch.backup_start) {
+ ret = fdt_add_mem_rsv(fdt, image->arch.backup_start,
+ BACKUP_SRC_SIZE);
+ if (ret) {
+ pr_err("Error reserving memory for backup: %s\n",
+ fdt_strerror(ret));
+ goto out;
+ }
}
ret = setup_new_fdt(image, fdt, initrd_load_addr, initrd_len,
@@ -1188,5 +1278,8 @@ int arch_kimage_file_post_load_cleanup(struct kimage *image)
kfree(image->arch.exclude_ranges);
image->arch.exclude_ranges = NULL;
+ vfree(image->arch.backup_buf);
+ image->arch.backup_buf = NULL;
+
return kexec_image_post_load_cleanup_default(image);
}
diff --git a/arch/powerpc/purgatory/Makefile b/arch/powerpc/purgatory/Makefile
index 348f5958..a494413 100644
--- a/arch/powerpc/purgatory/Makefile
+++ b/arch/powerpc/purgatory/Makefile
@@ -2,13 +2,37 @@
KASAN_SANITIZE := n
-targets += trampoline_$(BITS).o purgatory.ro kexec-purgatory.c
+purgatory-y := purgatory_$(BITS).o trampoline_$(BITS).o
+
+targets += $(purgatory-y)
+PURGATORY_OBJS = $(addprefix $(obj)/,$(purgatory-y))
LDFLAGS_purgatory.ro := -e purgatory_start -r --no-undefined
+targets += purgatory.ro
+
+PURGATORY_CFLAGS_REMOVE :=
+
+# Default KBUILD_CFLAGS can have -pg option set when FUNCTION_TRACE is
+# enabled leaving some undefined symbols like _mcount in purgatory.
+ifdef CONFIG_FUNCTION_TRACER
+PURGATORY_CFLAGS_REMOVE += $(CC_FLAGS_FTRACE)
+endif
+
+ifdef CONFIG_STACKPROTECTOR
+PURGATORY_CFLAGS_REMOVE += -fstack-protector
+endif
-$(obj)/purgatory.ro: $(obj)/trampoline_$(BITS).o FORCE
+ifdef CONFIG_STACKPROTECTOR_STRONG
+PURGATORY_CFLAGS_REMOVE += -fstack-protector-strong
+endif
+
+CFLAGS_REMOVE_purgatory_$(BITS).o += $(PURGATORY_CFLAGS_REMOVE)
+
+$(obj)/purgatory.ro: $(PURGATORY_OBJS) FORCE
$(call if_changed,ld)
+targets += kexec-purgatory.c
+
quiet_cmd_bin2c = BIN2C $@
cmd_bin2c = $(objtree)/scripts/bin2c kexec_purgatory < $< > $@
diff --git a/arch/powerpc/purgatory/purgatory_64.c b/arch/powerpc/purgatory/purgatory_64.c
new file mode 100644
index 0000000..1eca74c
--- /dev/null
+++ b/arch/powerpc/purgatory/purgatory_64.c
@@ -0,0 +1,36 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * purgatory: Runs between two kernels
+ *
+ * Copyright 2020, Hari Bathini, IBM Corporation.
+ */
+
+#include <asm/purgatory.h>
+#include <asm/crashdump-ppc64.h>
+
+extern unsigned long backup_start;
+
+static void *__memcpy(void *dest, const void *src, unsigned long n)
+{
+ unsigned long i;
+ unsigned char *d;
+ const unsigned char *s;
+
+ d = dest;
+ s = src;
+ for (i = 0; i < n; i++)
+ d[i] = s[i];
+
+ return dest;
+}
+
+void purgatory(void)
+{
+ void *dest, *src;
+
+ src = (void *)BACKUP_SRC_START;
+ if (backup_start) {
+ dest = (void *)backup_start;
+ __memcpy(dest, src, BACKUP_SRC_SIZE);
+ }
+}
diff --git a/arch/powerpc/purgatory/trampoline_64.S b/arch/powerpc/purgatory/trampoline_64.S
index 83e93b7..ef808d3 100644
--- a/arch/powerpc/purgatory/trampoline_64.S
+++ b/arch/powerpc/purgatory/trampoline_64.S
@@ -44,11 +44,6 @@ master:
mr %r17,%r3 /* save cpu id to r17 */
mr %r15,%r4 /* save physical address in reg15 */
- or %r3,%r3,%r3 /* ok now to high priority, lets boot */
- lis %r6,0x1
- mtctr %r6 /* delay a bit for slaves to catch up */
- bdnz . /* before we overwrite 0-100 again */
-
bl 0f /* Work out where we're running */
0: mflr %r18
@@ -56,6 +51,24 @@ master:
ld %r1,(stack - 0b)(%r18) /* setup stack */
+ /* Branch out to copy backup region, if required. */
+ ld %r12,(backup_start - 0b)(%r18)
+ cmpdi %cr0,%r12,0
+ beq 80f
+
+ subi %r1,%r1,112
+#if defined(_CALL_ELF) && _CALL_ELF == 2
+ bl purgatory
+#else
+ bl .purgatory
+#endif
+ nop
+80:
+ or %r3,%r3,%r3 /* ok now to high priority, lets boot */
+ lis %r6,0x1
+ mtctr %r6 /* delay a bit for slaves to catch up */
+ bdnz . /* before we overwrite 0-100 again */
+
/* load device-tree address */
ld %r3, (dt_offset - 0b)(%r18)
mr %r16,%r3 /* save dt address in reg16 */
@@ -112,6 +125,11 @@ dt_offset:
.8byte 0x0
.size dt_offset, . - dt_offset
+ .balign 8
+ .globl backup_start
+backup_start:
+ .8byte 0x0
+ .size backup_start, . - backup_start
.balign 8
.globl my_toc
^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v2 10/12] ppc64/kexec_file: prepare elfcore header for crashing kernel
2020-07-02 19:53 [PATCH v2 00/12] ppc64: enable kdump support for kexec_file_load syscall Hari Bathini
` (8 preceding siblings ...)
2020-07-02 19:56 ` [PATCH v2 09/12] ppc64/kexec_file: setup backup region for kdump kernel Hari Bathini
@ 2020-07-02 19:56 ` Hari Bathini
2020-07-02 19:56 ` [PATCH v2 11/12] ppc64/kexec_file: add appropriate regions for memory reserve map Hari Bathini
` (2 subsequent siblings)
12 siblings, 0 replies; 16+ messages in thread
From: Hari Bathini @ 2020-07-02 19:56 UTC (permalink / raw)
To: Michael Ellerman, Andrew Morton
Cc: Pingfan Liu, Kexec-ml, Petr Tesarik, Mahesh J Salgaonkar,
Sourabh Jain, lkml, linuxppc-dev, Mimi Zohar, Vivek Goyal,
Dave Young, Thiago Jung Bauermann, Eric Biederman
Prepare elf headers for the crashing kernel's core file using
crash_prepare_elf64_headers() and pass on this info to kdump
kernel by updating its command line with elfcorehdr parameter.
Also, add elfcorehdr location to reserve map to avoid it from
being stomped on while booting.
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
---
Changes in v2:
* Tried merging adjacent memory ranges on hitting maximum ranges limit
to reduce reallocations for memory ranges and also, minimize PT_LOAD
segments for elfcore.
* Updated add_rtas_mem_range() & add_opal_mem_range() callsites based on
the new prototype for these functions.
arch/powerpc/include/asm/kexec.h | 6 +
arch/powerpc/kexec/elf_64.c | 12 ++
arch/powerpc/kexec/file_load.c | 49 ++++++++++
arch/powerpc/kexec/file_load_64.c | 181 +++++++++++++++++++++++++++++++++++++
4 files changed, 248 insertions(+)
diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
index 037cf2b..8b0a6d6 100644
--- a/arch/powerpc/include/asm/kexec.h
+++ b/arch/powerpc/include/asm/kexec.h
@@ -112,12 +112,18 @@ struct kimage_arch {
unsigned long backup_start;
void *backup_buf;
+ unsigned long elfcorehdr_addr;
+ unsigned long elf_headers_sz;
+ void *elf_headers;
+
#ifdef CONFIG_IMA_KEXEC
phys_addr_t ima_buffer_addr;
size_t ima_buffer_size;
#endif
};
+char *setup_kdump_cmdline(struct kimage *image, char *cmdline,
+ unsigned long cmdline_len);
int setup_purgatory(struct kimage *image, const void *slave_code,
const void *fdt, unsigned long kernel_load_addr,
unsigned long fdt_load_addr);
diff --git a/arch/powerpc/kexec/elf_64.c b/arch/powerpc/kexec/elf_64.c
index 4838b42..40a028c 100644
--- a/arch/powerpc/kexec/elf_64.c
+++ b/arch/powerpc/kexec/elf_64.c
@@ -36,6 +36,7 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
void *fdt;
const void *slave_code;
struct elfhdr ehdr;
+ char *modified_cmdline = NULL;
struct kexec_elf_info elf_info;
struct kexec_buf kbuf = { .image = image, .buf_min = 0,
.buf_max = ppc64_rma_size };
@@ -74,6 +75,16 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
pr_err("Failed to load kdump kernel segments\n");
goto out;
}
+
+ /* Setup cmdline for kdump kernel case */
+ modified_cmdline = setup_kdump_cmdline(image, cmdline,
+ cmdline_len);
+ if (!modified_cmdline) {
+ pr_err("Setting up cmdline for kdump kernel failed\n");
+ ret = -EINVAL;
+ goto out;
+ }
+ cmdline = modified_cmdline;
}
if (initrd != NULL) {
@@ -130,6 +141,7 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
pr_err("Error setting up the purgatory.\n");
out:
+ kfree(modified_cmdline);
kexec_free_elf_info(&elf_info);
/* Make kimage_file_post_load_cleanup free the fdt buffer for us. */
diff --git a/arch/powerpc/kexec/file_load.c b/arch/powerpc/kexec/file_load.c
index 99a2c4d..2e74992 100644
--- a/arch/powerpc/kexec/file_load.c
+++ b/arch/powerpc/kexec/file_load.c
@@ -17,11 +17,46 @@
#include <linux/slab.h>
#include <linux/kexec.h>
#include <linux/libfdt.h>
+#include <asm/setup.h>
#include <asm/ima.h>
#define SLAVE_CODE_SIZE 256 /* First 0x100 bytes */
/**
+ * setup_kdump_cmdline - Prepend "elfcorehdr=<addr> " to command line
+ * of kdump kernel for exporting the core.
+ * @image: Kexec image
+ * @cmdline: Command line parameters to update.
+ * @cmdline_len: Length of the cmdline parameters.
+ *
+ * kdump segment must be setup before calling this function.
+ *
+ * Returns new cmdline buffer for kdump kernel on success, NULL otherwise.
+ */
+char *setup_kdump_cmdline(struct kimage *image, char *cmdline,
+ unsigned long cmdline_len)
+{
+ int elfcorehdr_strlen;
+ char *cmdline_ptr;
+
+ cmdline_ptr = kzalloc(COMMAND_LINE_SIZE, GFP_KERNEL);
+ if (!cmdline_ptr)
+ return NULL;
+
+ elfcorehdr_strlen = sprintf(cmdline_ptr, "elfcorehdr=0x%lx ",
+ image->arch.elfcorehdr_addr);
+
+ if (elfcorehdr_strlen + cmdline_len > COMMAND_LINE_SIZE) {
+ pr_err("Appending elfcorehdr=<addr> exceeds cmdline size\n");
+ kfree(cmdline_ptr);
+ return NULL;
+ }
+
+ memcpy(cmdline_ptr + elfcorehdr_strlen, cmdline, cmdline_len);
+ return cmdline_ptr;
+}
+
+/**
* setup_purgatory - initialize the purgatory's global variables
* @image: kexec image.
* @slave_code: Slave code for the purgatory.
@@ -215,6 +250,20 @@ int setup_new_fdt(const struct kimage *image, void *fdt,
}
}
+ if (image->type == KEXEC_TYPE_CRASH) {
+ /*
+ * Avoid elfcorehdr from being stomped on in kdump kernel by
+ * setting up memory reserve map.
+ */
+ ret = fdt_add_mem_rsv(fdt, image->arch.elfcorehdr_addr,
+ image->arch.elf_headers_sz);
+ if (ret) {
+ pr_err("Error reserving elfcorehdr memory: %s\n",
+ fdt_strerror(ret));
+ goto err;
+ }
+ }
+
ret = setup_ima_buffer(image, fdt, chosen_node);
if (ret) {
pr_err("Error setting up the new device tree.\n");
diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
index f91530e..6f895fa 100644
--- a/arch/powerpc/kexec/file_load_64.c
+++ b/arch/powerpc/kexec/file_load_64.c
@@ -122,6 +122,77 @@ static int get_usable_memory_ranges(struct crash_mem **mem_ranges)
}
/**
+ * get_crash_memory_ranges - Get crash memory ranges. This list includes
+ * first/crashing kernel's memory regions that
+ * would be exported via an elfcore.
+ * @mem_ranges: Range list to add the memory ranges to.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+static int get_crash_memory_ranges(struct crash_mem **mem_ranges)
+{
+ struct memblock_region *reg;
+ struct crash_mem *tmem;
+ int ret;
+
+ for_each_memblock(memory, reg) {
+ u64 base, size;
+
+ base = (u64)reg->base;
+ size = (u64)reg->size;
+
+ /* Skip backup memory region, which needs a separate entry */
+ if (base == BACKUP_SRC_START) {
+ if (size > BACKUP_SRC_SIZE) {
+ base = BACKUP_SRC_END + 1;
+ size -= BACKUP_SRC_SIZE;
+ } else
+ continue;
+ }
+
+ ret = add_mem_range(mem_ranges, base, size);
+ if (ret)
+ goto out;
+
+ /* Try merging adjacent ranges before reallocation attempt */
+ if ((*mem_ranges)->nr_ranges == (*mem_ranges)->max_nr_ranges)
+ sort_memory_ranges(*mem_ranges, true);
+ }
+
+ /* Reallocate memory ranges if there is no space to split ranges */
+ tmem = *mem_ranges;
+ if (tmem && (tmem->nr_ranges == tmem->max_nr_ranges)) {
+ tmem = realloc_mem_ranges(mem_ranges);
+ if (!tmem)
+ goto out;
+ }
+
+ /* Exclude crashkernel region */
+ ret = crash_exclude_mem_range(tmem, crashk_res.start, crashk_res.end);
+ if (ret)
+ goto out;
+
+ ret = add_rtas_mem_range(mem_ranges);
+ if (ret)
+ goto out;
+
+ ret = add_opal_mem_range(mem_ranges);
+ if (ret)
+ goto out;
+
+ /* create a separate program header for the backup region */
+ ret = add_mem_range(mem_ranges, BACKUP_SRC_START, BACKUP_SRC_SIZE);
+ if (ret)
+ goto out;
+
+ sort_memory_ranges(*mem_ranges, false);
+out:
+ if (ret)
+ pr_err("Failed to setup crash memory ranges\n");
+ return ret;
+}
+
+/**
* __locate_mem_hole_top_down - Looks top down for a large enough memory hole
* in the memory regions between buf_min & buf_max
* for the buffer. If found, sets kbuf->mem.
@@ -898,6 +969,103 @@ static int load_backup_segment(struct kimage *image, struct kexec_buf *kbuf)
}
/**
+ * update_backup_region_phdr - Update backup region's offset for the core to
+ * export the region appropriately.
+ * @image: Kexec image.
+ * @ehdr: ELF core header.
+ *
+ * Assumes an exclusive program header is setup for the backup region
+ * in the ELF headers
+ *
+ * Returns nothing.
+ */
+static void update_backup_region_phdr(struct kimage *image, Elf64_Ehdr *ehdr)
+{
+ Elf64_Phdr *phdr;
+ unsigned int i;
+
+ phdr = (Elf64_Phdr *)(ehdr + 1);
+ for (i = 0; i < ehdr->e_phnum; i++) {
+ if (phdr->p_paddr == BACKUP_SRC_START) {
+ phdr->p_offset = image->arch.backup_start;
+ pr_debug("Backup region offset updated to 0x%lx\n",
+ image->arch.backup_start);
+ return;
+ }
+ }
+}
+
+/**
+ * prepare_elf_headers - Prepare headers for the elfcore to be exported as
+ * /proc/vmcore by the kdump kernel.
+ * @image: Kexec image.
+ * @cmem: Crash memory ranges to be exported via elfcore.
+ * @addr: Vmalloc'd memory allocated by crash_prepare_elf64_headers
+ * to prepare the elf headers.
+ * @sz: Size of the vmalloc'd memory allocated.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+static int prepare_elf_headers(struct kimage *image, struct crash_mem *cmem,
+ void **addr, unsigned long *sz)
+{
+ int ret;
+
+ ret = crash_prepare_elf64_headers(cmem, false, addr, sz);
+
+ /* Fix the offset for backup region in the ELF header */
+ if (!ret)
+ update_backup_region_phdr(image, *addr);
+
+ return ret;
+}
+
+/**
+ * load_elfcorehdr_segment - Setup crash memory ranges and initialize elfcorehdr
+ * segment needed to load kdump kernel.
+ * @image: Kexec image.
+ * @kbuf: Buffer contents and memory parameters.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+static int load_elfcorehdr_segment(struct kimage *image, struct kexec_buf *kbuf)
+{
+ struct crash_mem *cmem = NULL;
+ unsigned long headers_sz;
+ void *headers = NULL;
+ int ret;
+
+ ret = get_crash_memory_ranges(&cmem);
+ if (ret)
+ goto out;
+
+ /* Setup elfcorehdr segment */
+ ret = prepare_elf_headers(image, cmem, &headers, &headers_sz);
+ if (ret) {
+ pr_err("Failed to prepare elf headers for the core\n");
+ goto out;
+ }
+
+ kbuf->buffer = headers;
+ kbuf->mem = KEXEC_BUF_MEM_UNKNOWN;
+ kbuf->bufsz = kbuf->memsz = headers_sz;
+ kbuf->top_down = false;
+
+ ret = kexec_add_buffer(kbuf);
+ if (ret) {
+ vfree(headers);
+ goto out;
+ }
+
+ image->arch.elfcorehdr_addr = kbuf->mem;
+ image->arch.elf_headers_sz = headers_sz;
+ image->arch.elf_headers = headers;
+out:
+ kfree(cmem);
+ return ret;
+}
+
+/**
* load_crashdump_segments_ppc64 - Initialize the additional segements needed
* to load kdump kernel.
* @image: Kexec image.
@@ -918,6 +1086,15 @@ int load_crashdump_segments_ppc64(struct kimage *image,
}
pr_debug("Loaded the backup region at 0x%lx\n", kbuf->mem);
+ /* Load elfcorehdr segment - to export crashing kernel's vmcore */
+ ret = load_elfcorehdr_segment(image, kbuf);
+ if (ret) {
+ pr_err("Failed to load elfcorehdr segment\n");
+ return ret;
+ }
+ pr_debug("Loaded elf core header at 0x%lx, bufsz=0x%lx memsz=0x%lx\n",
+ image->arch.elfcorehdr_addr, kbuf->bufsz, kbuf->memsz);
+
return 0;
}
@@ -1281,5 +1458,9 @@ int arch_kimage_file_post_load_cleanup(struct kimage *image)
vfree(image->arch.backup_buf);
image->arch.backup_buf = NULL;
+ vfree(image->arch.elf_headers);
+ image->arch.elf_headers = NULL;
+ image->arch.elf_headers_sz = 0;
+
return kexec_image_post_load_cleanup_default(image);
}
^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v2 11/12] ppc64/kexec_file: add appropriate regions for memory reserve map
2020-07-02 19:53 [PATCH v2 00/12] ppc64: enable kdump support for kexec_file_load syscall Hari Bathini
` (9 preceding siblings ...)
2020-07-02 19:56 ` [PATCH v2 10/12] ppc64/kexec_file: prepare elfcore header for crashing kernel Hari Bathini
@ 2020-07-02 19:56 ` Hari Bathini
2020-07-02 19:57 ` [PATCH v2 12/12] ppc64/kexec_file: fix kexec load failure with lack of memory hole Hari Bathini
2020-07-07 0:43 ` [PATCH v2 00/12] ppc64: enable kdump support for kexec_file_load syscall piliu
12 siblings, 0 replies; 16+ messages in thread
From: Hari Bathini @ 2020-07-02 19:56 UTC (permalink / raw)
To: Michael Ellerman, Andrew Morton
Cc: Pingfan Liu, Kexec-ml, Petr Tesarik, Mahesh J Salgaonkar,
Sourabh Jain, lkml, linuxppc-dev, Mimi Zohar, Vivek Goyal,
Dave Young, Thiago Jung Bauermann, Eric Biederman
While initrd, elfcorehdr and backup regions are already added to the
reserve map, there are a few missing regions that need to be added to
the memory reserve map. Add them here. And now that all the changes
to load panic kernel are in place, claim likewise.
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
---
Changes in v2:
* Updated add_rtas_mem_range() & add_opal_mem_range() callsites based on
the new prototype for these functions.
arch/powerpc/kexec/file_load_64.c | 58 ++++++++++++++++++++++++++++++++++---
1 file changed, 53 insertions(+), 5 deletions(-)
diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
index 6f895fa..d3b29e0 100644
--- a/arch/powerpc/kexec/file_load_64.c
+++ b/arch/powerpc/kexec/file_load_64.c
@@ -193,6 +193,34 @@ static int get_crash_memory_ranges(struct crash_mem **mem_ranges)
}
/**
+ * get_reserved_memory_ranges - Get reserve memory ranges. This list includes
+ * memory regions that should be added to the
+ * memory reserve map to ensure the region is
+ * protected from any mischeif.
+ * @mem_ranges: Range list to add the memory ranges to.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+static int get_reserved_memory_ranges(struct crash_mem **mem_ranges)
+{
+ int ret;
+
+ ret = add_rtas_mem_range(mem_ranges);
+ if (ret)
+ goto out;
+
+ ret = add_tce_mem_ranges(mem_ranges);
+ if (ret)
+ goto out;
+
+ ret = add_reserved_ranges(mem_ranges);
+out:
+ if (ret)
+ pr_err("Failed to setup reserved memory ranges\n");
+ return ret;
+}
+
+/**
* __locate_mem_hole_top_down - Looks top down for a large enough memory hole
* in the memory regions between buf_min & buf_max
* for the buffer. If found, sets kbuf->mem.
@@ -1200,8 +1228,8 @@ int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
unsigned long initrd_load_addr,
unsigned long initrd_len, const char *cmdline)
{
- struct crash_mem *umem = NULL;
- int chosen_node, ret;
+ struct crash_mem *umem = NULL, *rmem = NULL;
+ int i, nr_ranges, chosen_node, ret;
/* Remove memory reservation for the current device tree. */
ret = delete_fdt_mem_rsv(fdt, __pa(initial_boot_params),
@@ -1247,6 +1275,25 @@ int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
}
}
+ /* Update memory reserve map */
+ ret = get_reserved_memory_ranges(&rmem);
+ if (ret)
+ goto out;
+
+ nr_ranges = rmem ? rmem->nr_ranges : 0;
+ for (i = 0; i < nr_ranges; i++) {
+ u64 base, size;
+
+ base = rmem->ranges[i].start;
+ size = rmem->ranges[i].end - base + 1;
+ ret = fdt_add_mem_rsv(fdt, base, size);
+ if (ret) {
+ pr_err("Error updating memory reserve map: %s\n",
+ fdt_strerror(ret));
+ goto out;
+ }
+ }
+
ret = setup_new_fdt(image, fdt, initrd_load_addr, initrd_len,
cmdline, &chosen_node);
if (ret)
@@ -1257,6 +1304,7 @@ int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
pr_err("Failed to update device-tree with linux,booted-from-kexec\n");
out:
kfree(umem);
+ kfree(rmem);
return ret;
}
@@ -1434,10 +1482,10 @@ int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
/* Get exclude memory ranges needed for setting up kdump segments */
ret = get_exclude_memory_ranges(&(image->arch.exclude_ranges));
- if (ret)
+ if (ret) {
pr_err("Failed to setup exclude memory ranges for buffer lookup\n");
- /* Return this until all changes for panic kernel are in */
- return -EOPNOTSUPP;
+ return ret;
+ }
}
return kexec_image_probe_default(image, buf, buf_len);
^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v2 12/12] ppc64/kexec_file: fix kexec load failure with lack of memory hole
2020-07-02 19:53 [PATCH v2 00/12] ppc64: enable kdump support for kexec_file_load syscall Hari Bathini
` (10 preceding siblings ...)
2020-07-02 19:56 ` [PATCH v2 11/12] ppc64/kexec_file: add appropriate regions for memory reserve map Hari Bathini
@ 2020-07-02 19:57 ` Hari Bathini
2020-07-07 0:43 ` [PATCH v2 00/12] ppc64: enable kdump support for kexec_file_load syscall piliu
12 siblings, 0 replies; 16+ messages in thread
From: Hari Bathini @ 2020-07-02 19:57 UTC (permalink / raw)
To: Michael Ellerman, Andrew Morton
Cc: Pingfan Liu, Kexec-ml, Petr Tesarik, Mahesh J Salgaonkar,
Sourabh Jain, lkml, linuxppc-dev, Mimi Zohar, Vivek Goyal,
Dave Young, Thiago Jung Bauermann, Eric Biederman
The kexec purgatory has to run in real mode. Only the first memory
block maybe accessible in real mode. And, unlike the case with panic
kernel, no memory is set aside for regular kexec load. Another thing
to note is, the memory for crashkernel is reserved at an offset of
128MB. So, when crashkernel memory is reserved, the memory ranges to
load kexec segments shrink further as the generic code only looks for
memblock free memory ranges and in all likelihood only a tiny bit of
memory from 0 to 128MB would be available to load kexec segments.
With kdump being used by default in general, kexec file load is likely
to fail almost always. This can be fixed by changing the memory hole
lookup logic for regular kexec to use the same method as kdump. This
would mean that most kexec segments will overlap with crashkernel
memory region. That should still be ok as the pages, whose destination
address isn't available while loading, are placed in an intermediate
location till a flush to the actual destination address happens during
kexec boot sequence.
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
---
Changes in v2:
* New patch to fix locating memory hole for kexec_file_load (kexec -s -l)
when memory is reserved for crashkernel.
arch/powerpc/kexec/file_load_64.c | 33 ++++++++++++++-------------------
1 file changed, 14 insertions(+), 19 deletions(-)
diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
index d3b29e0..746c16f 100644
--- a/arch/powerpc/kexec/file_load_64.c
+++ b/arch/powerpc/kexec/file_load_64.c
@@ -1326,13 +1326,6 @@ int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf)
u64 buf_min, buf_max;
int ret;
- /*
- * Use the generic kexec_locate_mem_hole for regular
- * kexec_file_load syscall
- */
- if (kbuf->image->type != KEXEC_TYPE_CRASH)
- return kexec_locate_mem_hole(kbuf);
-
/* Look up the exclude ranges list while locating the memory hole */
emem = &(kbuf->image->arch.exclude_ranges);
if (!(*emem) || ((*emem)->nr_ranges == 0)) {
@@ -1340,11 +1333,15 @@ int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf)
return 0;
}
+ buf_min = kbuf->buf_min;
+ buf_max = kbuf->buf_max;
/* Segments for kdump kernel should be within crashkernel region */
- buf_min = (kbuf->buf_min < crashk_res.start ?
- crashk_res.start : kbuf->buf_min);
- buf_max = (kbuf->buf_max > crashk_res.end ?
- crashk_res.end : kbuf->buf_max);
+ if (kbuf->image->type == KEXEC_TYPE_CRASH) {
+ buf_min = (buf_min < crashk_res.start ?
+ crashk_res.start : buf_min);
+ buf_max = (buf_max > crashk_res.end ?
+ crashk_res.end : buf_max);
+ }
if (buf_min > buf_max) {
pr_err("Invalid buffer min and/or max values\n");
@@ -1477,15 +1474,13 @@ int arch_kexec_apply_relocations_add(struct purgatory_info *pi,
int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
unsigned long buf_len)
{
- if (image->type == KEXEC_TYPE_CRASH) {
- int ret;
+ int ret;
- /* Get exclude memory ranges needed for setting up kdump segments */
- ret = get_exclude_memory_ranges(&(image->arch.exclude_ranges));
- if (ret) {
- pr_err("Failed to setup exclude memory ranges for buffer lookup\n");
- return ret;
- }
+ /* Get exclude memory ranges needed for setting up kexec segments */
+ ret = get_exclude_memory_ranges(&(image->arch.exclude_ranges));
+ if (ret) {
+ pr_err("Failed to setup exclude memory ranges for buffer lookup\n");
+ return ret;
}
return kexec_image_probe_default(image, buf, buf_len);
^ permalink raw reply related [flat|nested] 16+ messages in thread
* Re: [PATCH v2 01/12] kexec_file: allow archs to handle special regions while locating memory hole
2020-07-02 19:54 ` [PATCH v2 01/12] kexec_file: allow archs to handle special regions while locating memory hole Hari Bathini
@ 2020-07-06 9:07 ` Dave Young
0 siblings, 0 replies; 16+ messages in thread
From: Dave Young @ 2020-07-06 9:07 UTC (permalink / raw)
To: Hari Bathini
Cc: Thiago Jung Bauermann, kernel test robot, Pingfan Liu, Kexec-ml,
Mahesh J Salgaonkar, Petr Tesarik, lkml, linuxppc-dev,
Mimi Zohar, Sourabh Jain, Andrew Morton, Vivek Goyal,
Eric Biederman
On 07/03/20 at 01:24am, Hari Bathini wrote:
> Some architectures may have special memory regions, within the given
> memory range, which can't be used for the buffer in a kexec segment.
> Implement weak arch_kexec_locate_mem_hole() definition which arch code
> may override, to take care of special regions, while trying to locate
> a memory hole.
>
> Also, add the missing declarations for arch overridable functions and
> and drop the __weak descriptors in the declarations to avoid non-weak
> definitions from becoming weak.
>
> Reported-by: kernel test robot <lkp@intel.com>
> [lkp: In v1, arch_kimage_file_post_load_cleanup() declaration was missing]
> Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
> ---
>
> Changes in v2:
> * Introduced arch_kexec_locate_mem_hole() for override and dropped
> weak arch_kexec_add_buffer().
> * Dropped __weak identifier for arch overridable functions.
> * Fixed the missing declaration for arch_kimage_file_post_load_cleanup()
> reported by lkp. lkp report for reference:
> - https://lore.kernel.org/patchwork/patch/1264418/
>
>
> include/linux/kexec.h | 29 ++++++++++++++++++-----------
> kernel/kexec_file.c | 16 ++++++++++++++--
> 2 files changed, 32 insertions(+), 13 deletions(-)
>
> diff --git a/include/linux/kexec.h b/include/linux/kexec.h
> index ea67910..9e93bef 100644
> --- a/include/linux/kexec.h
> +++ b/include/linux/kexec.h
> @@ -183,17 +183,24 @@ int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name,
> bool get_value);
> void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name);
>
> -int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
> - unsigned long buf_len);
> -void * __weak arch_kexec_kernel_image_load(struct kimage *image);
> -int __weak arch_kexec_apply_relocations_add(struct purgatory_info *pi,
> - Elf_Shdr *section,
> - const Elf_Shdr *relsec,
> - const Elf_Shdr *symtab);
> -int __weak arch_kexec_apply_relocations(struct purgatory_info *pi,
> - Elf_Shdr *section,
> - const Elf_Shdr *relsec,
> - const Elf_Shdr *symtab);
> +/* Architectures may override the below functions */
> +int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
> + unsigned long buf_len);
> +void *arch_kexec_kernel_image_load(struct kimage *image);
> +int arch_kexec_apply_relocations_add(struct purgatory_info *pi,
> + Elf_Shdr *section,
> + const Elf_Shdr *relsec,
> + const Elf_Shdr *symtab);
> +int arch_kexec_apply_relocations(struct purgatory_info *pi,
> + Elf_Shdr *section,
> + const Elf_Shdr *relsec,
> + const Elf_Shdr *symtab);
> +int arch_kimage_file_post_load_cleanup(struct kimage *image);
> +#ifdef CONFIG_KEXEC_SIG
> +int arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
> + unsigned long buf_len);
> +#endif
> +int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf);
>
> extern int kexec_add_buffer(struct kexec_buf *kbuf);
> int kexec_locate_mem_hole(struct kexec_buf *kbuf);
> diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
> index 09cc78d..e89912d 100644
> --- a/kernel/kexec_file.c
> +++ b/kernel/kexec_file.c
> @@ -636,6 +636,19 @@ int kexec_locate_mem_hole(struct kexec_buf *kbuf)
> }
>
> /**
> + * arch_kexec_locate_mem_hole - Find free memory to place the segments.
> + * @kbuf: Parameters for the memory search.
> + *
> + * On success, kbuf->mem will have the start address of the memory region found.
> + *
> + * Return: 0 on success, negative errno on error.
> + */
> +int __weak arch_kexec_locate_mem_hole(struct kexec_buf *kbuf)
> +{
> + return kexec_locate_mem_hole(kbuf);
> +}
> +
> +/**
> * kexec_add_buffer - place a buffer in a kexec segment
> * @kbuf: Buffer contents and memory parameters.
> *
> @@ -647,7 +660,6 @@ int kexec_locate_mem_hole(struct kexec_buf *kbuf)
> */
> int kexec_add_buffer(struct kexec_buf *kbuf)
> {
> -
> struct kexec_segment *ksegment;
> int ret;
>
> @@ -675,7 +687,7 @@ int kexec_add_buffer(struct kexec_buf *kbuf)
> kbuf->buf_align = max(kbuf->buf_align, PAGE_SIZE);
>
> /* Walk the RAM ranges and allocate a suitable range for the buffer */
> - ret = kexec_locate_mem_hole(kbuf);
> + ret = arch_kexec_locate_mem_hole(kbuf);
> if (ret)
> return ret;
>
>
Acked-by: Dave Young <dyoung@redhat.com>
Thanks
Dave
^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH v2 00/12] ppc64: enable kdump support for kexec_file_load syscall
2020-07-02 19:53 [PATCH v2 00/12] ppc64: enable kdump support for kexec_file_load syscall Hari Bathini
` (11 preceding siblings ...)
2020-07-02 19:57 ` [PATCH v2 12/12] ppc64/kexec_file: fix kexec load failure with lack of memory hole Hari Bathini
@ 2020-07-07 0:43 ` piliu
12 siblings, 0 replies; 16+ messages in thread
From: piliu @ 2020-07-07 0:43 UTC (permalink / raw)
To: Hari Bathini, Michael Ellerman, Andrew Morton
Cc: Kexec-ml, Petr Tesarik, Mahesh J Salgaonkar, Sourabh Jain, lkml,
linuxppc-dev, Mimi Zohar, Vivek Goyal, Dave Young,
Thiago Jung Bauermann, Eric Biederman
On 07/03/2020 03:53 AM, Hari Bathini wrote:
> This patch series enables kdump support for kexec_file_load system
> call (kexec -s -p) on PPC64. The changes are inspired from kexec-tools
> code but heavily modified for kernel consumption. There is scope to
> expand purgatory to verify sha256 digest along with other improvements
> in purgatory code. Will deal with those changes in a separate patch
> series later.
>
> The first patch adds a weak arch_kexec_locate_mem_hole() function to
> override locate memory hole logic suiting arch needs. There are some
> special regions in ppc64 which should be avoided while loading buffer
> & there are multiple callers to kexec_add_buffer making it complicated
> to maintain range sanity and using generic lookup at the same time.
>
> The second patch marks ppc64 specific code within arch/powerpc/kexec
> and arch/powerpc/purgatory to make the subsequent code changes easy
> to understand.
>
> The next patch adds helper function to setup different memory ranges
> needed for loading kdump kernel, booting into it and exporting the
> crashing kernel's elfcore.
>
> The fourth patch overrides arch_kexec_locate_mem_hole() function to
> locate memory hole for kdump segments by accounting for the special
> memory regions, referred to as excluded memory ranges, and sets
> kbuf->mem when a suitable memory region is found.
>
> The fifth patch moves walk_drmem_lmbs() out of .init section with
> a few changes to reuse it for setting up kdump kernel's usable memory
> ranges. The next patch uses walk_drmem_lmbs() to look up the LMBs
> and set linux,drconf-usable-memory & linux,usable-memory properties
> in order to restrict kdump kernel's memory usage.
>
> The seventh patch adds relocation support for the purgatory. Patch 8
> helps setup the stack for the purgatory. The next patch setups up
> backup region as a segment while loading kdump kernel and teaches
> purgatory to copy it from source to destination.
>
> Patch 10 builds the elfcore header for the running kernel & passes
> the info to kdump kernel via "elfcorehdr=" parameter to export as
> /proc/vmcore file. The next patch sets up the memory reserve map
> for the kexec kernel and also claims kdump support for kdump as
> all the necessary changes are added.
>
> The last patch fixes a lookup issue for `kexec -l -s` case when
> memory is reserved for crashkernel.
>
> Tested the changes successfully on P8, P9 lpars, couple of OpenPOWER
> boxes and a simulator.
>
> Changes in v2:
> * Introduced arch_kexec_locate_mem_hole() for override and dropped
> weak arch_kexec_add_buffer().
> * Addressed warnings reported by lkp.
> * Added patch to address kexec load issue when memory is reserved
> for crashkernel.
> * Used the appropriate license header for the new files added.
> * Added an option to merge ranges to minimize reallocations while
> adding memory ranges.
> * Dropped within_crashkernel parameter for add_opal_mem_range() &
> add_rtas_mem_range() functions as it is not really needed.
>
> ---
>
> Hari Bathini (12):
> kexec_file: allow archs to handle special regions while locating memory hole
> powerpc/kexec_file: mark PPC64 specific code
> powerpc/kexec_file: add helper functions for getting memory ranges
> ppc64/kexec_file: avoid stomping memory used by special regions
> powerpc/drmem: make lmb walk a bit more flexible
> ppc64/kexec_file: restrict memory usage of kdump kernel
> ppc64/kexec_file: add support to relocate purgatory
> ppc64/kexec_file: setup the stack for purgatory
> ppc64/kexec_file: setup backup region for kdump kernel
> ppc64/kexec_file: prepare elfcore header for crashing kernel
> ppc64/kexec_file: add appropriate regions for memory reserve map
> ppc64/kexec_file: fix kexec load failure with lack of memory hole
>
>
> arch/powerpc/include/asm/crashdump-ppc64.h | 15
> arch/powerpc/include/asm/drmem.h | 9
> arch/powerpc/include/asm/kexec.h | 35 +
> arch/powerpc/include/asm/kexec_ranges.h | 18
> arch/powerpc/include/asm/purgatory.h | 11
> arch/powerpc/kernel/prom.c | 13
> arch/powerpc/kexec/Makefile | 2
> arch/powerpc/kexec/elf_64.c | 35 +
> arch/powerpc/kexec/file_load.c | 78 +
> arch/powerpc/kexec/file_load_64.c | 1509 ++++++++++++++++++++++++++++
> arch/powerpc/kexec/ranges.c | 397 +++++++
> arch/powerpc/mm/drmem.c | 87 +-
> arch/powerpc/mm/numa.c | 13
> arch/powerpc/purgatory/Makefile | 28 -
> arch/powerpc/purgatory/purgatory_64.c | 36 +
> arch/powerpc/purgatory/trampoline.S | 117 --
> arch/powerpc/purgatory/trampoline_64.S | 175 +++
> include/linux/kexec.h | 29 -
> kernel/kexec_file.c | 16
> 19 files changed, 2413 insertions(+), 210 deletions(-)
> create mode 100644 arch/powerpc/include/asm/crashdump-ppc64.h
> create mode 100644 arch/powerpc/include/asm/kexec_ranges.h
> create mode 100644 arch/powerpc/include/asm/purgatory.h
> create mode 100644 arch/powerpc/kexec/file_load_64.c
> create mode 100644 arch/powerpc/kexec/ranges.c
> create mode 100644 arch/powerpc/purgatory/purgatory_64.c
> delete mode 100644 arch/powerpc/purgatory/trampoline.S
> create mode 100644 arch/powerpc/purgatory/trampoline_64.S
>
Tested-by: Pingfan Liu <piliu@redhat.com>
^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH v2 02/12] powerpc/kexec_file: mark PPC64 specific code
2020-07-02 19:54 ` [PATCH v2 02/12] powerpc/kexec_file: mark PPC64 specific code Hari Bathini
@ 2020-07-10 7:52 ` Laurent Dufour
0 siblings, 0 replies; 16+ messages in thread
From: Laurent Dufour @ 2020-07-10 7:52 UTC (permalink / raw)
To: linuxppc-dev
Le 02/07/2020 à 21:54, Hari Bathini a écrit :
> Some of the kexec_file_load code isn't PPC64 specific. Move PPC64
> specific code from kexec/file_load.c to kexec/file_load_64.c. Also,
> rename purgatory/trampoline.S to purgatory/trampoline_64.S in the
> same spirit.
FWIW and despite a minor comment below,
Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>
> Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
> ---
>
> Changes in v2:
> * No changes.
>
>
> arch/powerpc/include/asm/kexec.h | 11 +++
> arch/powerpc/kexec/Makefile | 2 -
> arch/powerpc/kexec/elf_64.c | 7 +-
> arch/powerpc/kexec/file_load.c | 37 ++--------
> arch/powerpc/kexec/file_load_64.c | 108 ++++++++++++++++++++++++++++++
> arch/powerpc/purgatory/Makefile | 4 +
> arch/powerpc/purgatory/trampoline.S | 117 --------------------------------
> arch/powerpc/purgatory/trampoline_64.S | 117 ++++++++++++++++++++++++++++++++
> 8 files changed, 248 insertions(+), 155 deletions(-)
> create mode 100644 arch/powerpc/kexec/file_load_64.c
> delete mode 100644 arch/powerpc/purgatory/trampoline.S
> create mode 100644 arch/powerpc/purgatory/trampoline_64.S
>
> diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
> index c684768..7008ea1 100644
> --- a/arch/powerpc/include/asm/kexec.h
> +++ b/arch/powerpc/include/asm/kexec.h
> @@ -114,8 +114,17 @@ int setup_purgatory(struct kimage *image, const void *slave_code,
> unsigned long fdt_load_addr);
> int setup_new_fdt(const struct kimage *image, void *fdt,
> unsigned long initrd_load_addr, unsigned long initrd_len,
> - const char *cmdline);
> + const char *cmdline, int *node);
> int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size);
> +
> +#ifdef CONFIG_PPC64
> +int setup_purgatory_ppc64(struct kimage *image, const void *slave_code,
> + const void *fdt, unsigned long kernel_load_addr,
> + unsigned long fdt_load_addr);
> +int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
> + unsigned long initrd_load_addr,
> + unsigned long initrd_len, const char *cmdline);
> +#endif /* CONFIG_PPC64 */
> #endif /* CONFIG_KEXEC_FILE */
>
> #else /* !CONFIG_KEXEC_CORE */
> diff --git a/arch/powerpc/kexec/Makefile b/arch/powerpc/kexec/Makefile
> index 86380c6..67c3553 100644
> --- a/arch/powerpc/kexec/Makefile
> +++ b/arch/powerpc/kexec/Makefile
> @@ -7,7 +7,7 @@ obj-y += core.o crash.o core_$(BITS).o
>
> obj-$(CONFIG_PPC32) += relocate_32.o
>
> -obj-$(CONFIG_KEXEC_FILE) += file_load.o elf_$(BITS).o
> +obj-$(CONFIG_KEXEC_FILE) += file_load.o file_load_$(BITS).o elf_$(BITS).o
>
> ifdef CONFIG_HAVE_IMA_KEXEC
> ifdef CONFIG_IMA
> diff --git a/arch/powerpc/kexec/elf_64.c b/arch/powerpc/kexec/elf_64.c
> index 3072fd6..23ad04c 100644
> --- a/arch/powerpc/kexec/elf_64.c
> +++ b/arch/powerpc/kexec/elf_64.c
> @@ -88,7 +88,8 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
> goto out;
> }
>
> - ret = setup_new_fdt(image, fdt, initrd_load_addr, initrd_len, cmdline);
> + ret = setup_new_fdt_ppc64(image, fdt, initrd_load_addr,
> + initrd_len, cmdline);
> if (ret)
> goto out;
>
> @@ -107,8 +108,8 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
> pr_debug("Loaded device tree at 0x%lx\n", fdt_load_addr);
>
> slave_code = elf_info.buffer + elf_info.proghdrs[0].p_offset;
> - ret = setup_purgatory(image, slave_code, fdt, kernel_load_addr,
> - fdt_load_addr);
> + ret = setup_purgatory_ppc64(image, slave_code, fdt, kernel_load_addr,
> + fdt_load_addr);
> if (ret)
> pr_err("Error setting up the purgatory.\n");
>
> diff --git a/arch/powerpc/kexec/file_load.c b/arch/powerpc/kexec/file_load.c
> index 143c917..99a2c4d 100644
> --- a/arch/powerpc/kexec/file_load.c
> +++ b/arch/powerpc/kexec/file_load.c
> @@ -1,6 +1,6 @@
> // SPDX-License-Identifier: GPL-2.0-only
> /*
> - * ppc64 code to implement the kexec_file_load syscall
> + * powerpc code to implement the kexec_file_load syscall
> *
> * Copyright (C) 2004 Adam Litke (agl@us.ibm.com)
> * Copyright (C) 2004 IBM Corp.
> @@ -16,26 +16,10 @@
>
> #include <linux/slab.h>
> #include <linux/kexec.h>
> -#include <linux/of_fdt.h>
> #include <linux/libfdt.h>
> #include <asm/ima.h>
>
> -#define SLAVE_CODE_SIZE 256
> -
> -const struct kexec_file_ops * const kexec_file_loaders[] = {
> - &kexec_elf64_ops,
> - NULL
> -};
> -
> -int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
> - unsigned long buf_len)
> -{
> - /* We don't support crash kernels yet. */
> - if (image->type == KEXEC_TYPE_CRASH)
> - return -EOPNOTSUPP;
> -
> - return kexec_image_probe_default(image, buf, buf_len);
> -}
> +#define SLAVE_CODE_SIZE 256 /* First 0x100 bytes */
>
> /**
> * setup_purgatory - initialize the purgatory's global variables
> @@ -127,24 +111,17 @@ int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size)
> * @initrd_len: Size of the next initrd, or 0 if there will be none.
> * @cmdline: Command line for the next kernel, or NULL if there will
> * be none.
> + * @chosen_node: Set this output parameter to chosen_node.
minor: ^ seems to be "node"
> *
> * Return: 0 on success, or negative errno on error.
> */
> int setup_new_fdt(const struct kimage *image, void *fdt,
> unsigned long initrd_load_addr, unsigned long initrd_len,
> - const char *cmdline)
> + const char *cmdline, int *node)
> {
> int ret, chosen_node;
> const void *prop;
>
> - /* Remove memory reservation for the current device tree. */
> - ret = delete_fdt_mem_rsv(fdt, __pa(initial_boot_params),
> - fdt_totalsize(initial_boot_params));
> - if (ret == 0)
> - pr_debug("Removed old device tree reservation.\n");
> - else if (ret != -ENOENT)
> - return ret;
> -
> chosen_node = fdt_path_offset(fdt, "/chosen");
> if (chosen_node == -FDT_ERR_NOTFOUND) {
> chosen_node = fdt_add_subnode(fdt, fdt_path_offset(fdt, "/"),
> @@ -157,6 +134,8 @@ int setup_new_fdt(const struct kimage *image, void *fdt,
> pr_err("Malformed device tree: error reading /chosen.\n");
> return -EINVAL;
> }
> + if (node)
> + *node = chosen_node;
>
> /* Did we boot using an initrd? */
> prop = fdt_getprop(fdt, chosen_node, "linux,initrd-start", NULL);
> @@ -242,10 +221,6 @@ int setup_new_fdt(const struct kimage *image, void *fdt,
> return ret;
> }
>
> - ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
> - if (ret)
> - goto err;
> -
> return 0;
>
> err:
> diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
> new file mode 100644
> index 0000000..e6bff960
> --- /dev/null
> +++ b/arch/powerpc/kexec/file_load_64.c
> @@ -0,0 +1,108 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * ppc64 code to implement the kexec_file_load syscall
> + *
> + * Copyright (C) 2004 Adam Litke (agl@us.ibm.com)
> + * Copyright (C) 2004 IBM Corp.
> + * Copyright (C) 2004,2005 Milton D Miller II, IBM Corporation
> + * Copyright (C) 2005 R Sharada (sharada@in.ibm.com)
> + * Copyright (C) 2006 Mohan Kumar M (mohan@in.ibm.com)
> + * Copyright (C) 2020 IBM Corporation
> + *
> + * Based on kexec-tools' kexec-ppc64.c, kexec-elf-rel-ppc64.c, fs2dt.c.
> + * Heavily modified for the kernel by
> + * Hari Bathini <hbathini@linux.ibm.com>.
> + */
> +
> +#include <linux/kexec.h>
> +#include <linux/of_fdt.h>
> +#include <linux/libfdt.h>
> +
> +const struct kexec_file_ops * const kexec_file_loaders[] = {
> + &kexec_elf64_ops,
> + NULL
> +};
> +
> +/**
> + * setup_purgatory_ppc64 - initialize PPC64 specific purgatory's global
> + * variables and call setup_purgatory() to initialize
> + * common global variable.
> + * @image: kexec image.
> + * @slave_code: Slave code for the purgatory.
> + * @fdt: Flattened device tree for the next kernel.
> + * @kernel_load_addr: Address where the kernel is loaded.
> + * @fdt_load_addr: Address where the flattened device tree is loaded.
> + *
> + * Returns 0 on success, negative errno on error.
> + */
> +int setup_purgatory_ppc64(struct kimage *image, const void *slave_code,
> + const void *fdt, unsigned long kernel_load_addr,
> + unsigned long fdt_load_addr)
> +{
> + int ret;
> +
> + ret = setup_purgatory(image, slave_code, fdt, kernel_load_addr,
> + fdt_load_addr);
> + if (ret)
> + pr_err("Failed to setup purgatory symbols");
> + return ret;
> +}
> +
> +/**
> + * setup_new_fdt_ppc64 - Update the flattend device-tree of the kernel
> + * being loaded.
> + * @image: kexec image being loaded.
> + * @fdt: Flattened device tree for the next kernel.
> + * @initrd_load_addr: Address where the next initrd will be loaded.
> + * @initrd_len: Size of the next initrd, or 0 if there will be none.
> + * @cmdline: Command line for the next kernel, or NULL if there will
> + * be none.
> + *
> + * Returns 0 on success, negative errno on error.
> + */
> +int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
> + unsigned long initrd_load_addr,
> + unsigned long initrd_len, const char *cmdline)
> +{
> + int chosen_node, ret;
> +
> + /* Remove memory reservation for the current device tree. */
> + ret = delete_fdt_mem_rsv(fdt, __pa(initial_boot_params),
> + fdt_totalsize(initial_boot_params));
> + if (ret == 0)
> + pr_debug("Removed old device tree reservation.\n");
> + else if (ret != -ENOENT) {
> + pr_err("Failed to remove old device-tree reservation.\n");
> + return ret;
> + }
> +
> + ret = setup_new_fdt(image, fdt, initrd_load_addr, initrd_len,
> + cmdline, &chosen_node);
> + if (ret)
> + return ret;
> +
> + ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
> + if (ret)
> + pr_err("Failed to update device-tree with linux,booted-from-kexec\n");
> +
> + return ret;
> +}
> +
> +/**
> + * arch_kexec_kernel_image_probe - Does additional handling needed to setup
> + * kexec segments.
> + * @image: kexec image being loaded.
> + * @buf: Buffer pointing to elf data.
> + * @buf_len: Length of the buffer.
> + *
> + * Returns 0 on success, negative errno on error.
> + */
> +int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
> + unsigned long buf_len)
> +{
> + /* We don't support crash kernels yet. */
> + if (image->type == KEXEC_TYPE_CRASH)
> + return -EOPNOTSUPP;
> +
> + return kexec_image_probe_default(image, buf, buf_len);
> +}
> diff --git a/arch/powerpc/purgatory/Makefile b/arch/powerpc/purgatory/Makefile
> index 7c6d8b1..348f5958 100644
> --- a/arch/powerpc/purgatory/Makefile
> +++ b/arch/powerpc/purgatory/Makefile
> @@ -2,11 +2,11 @@
>
> KASAN_SANITIZE := n
>
> -targets += trampoline.o purgatory.ro kexec-purgatory.c
> +targets += trampoline_$(BITS).o purgatory.ro kexec-purgatory.c
>
> LDFLAGS_purgatory.ro := -e purgatory_start -r --no-undefined
>
> -$(obj)/purgatory.ro: $(obj)/trampoline.o FORCE
> +$(obj)/purgatory.ro: $(obj)/trampoline_$(BITS).o FORCE
> $(call if_changed,ld)
>
> quiet_cmd_bin2c = BIN2C $@
> diff --git a/arch/powerpc/purgatory/trampoline.S b/arch/powerpc/purgatory/trampoline.S
> deleted file mode 100644
> index a5a83c3..0000000
> --- a/arch/powerpc/purgatory/trampoline.S
> +++ /dev/null
> @@ -1,117 +0,0 @@
> -/* SPDX-License-Identifier: GPL-2.0-only */
> -/*
> - * kexec trampoline
> - *
> - * Based on code taken from kexec-tools and kexec-lite.
> - *
> - * Copyright (C) 2004 - 2005, Milton D Miller II, IBM Corporation
> - * Copyright (C) 2006, Mohan Kumar M, IBM Corporation
> - * Copyright (C) 2013, Anton Blanchard, IBM Corporation
> - */
> -
> -#include <asm/asm-compat.h>
> -
> - .machine ppc64
> - .balign 256
> - .globl purgatory_start
> -purgatory_start:
> - b master
> -
> - /* ABI: possible run_at_load flag at 0x5c */
> - .org purgatory_start + 0x5c
> - .globl run_at_load
> -run_at_load:
> - .long 0
> - .size run_at_load, . - run_at_load
> -
> - /* ABI: slaves start at 60 with r3=phys */
> - .org purgatory_start + 0x60
> -slave:
> - b .
> - /* ABI: end of copied region */
> - .org purgatory_start + 0x100
> - .size purgatory_start, . - purgatory_start
> -
> -/*
> - * The above 0x100 bytes at purgatory_start are replaced with the
> - * code from the kernel (or next stage) by setup_purgatory().
> - */
> -
> -master:
> - or %r1,%r1,%r1 /* low priority to let other threads catchup */
> - isync
> - mr %r17,%r3 /* save cpu id to r17 */
> - mr %r15,%r4 /* save physical address in reg15 */
> -
> - or %r3,%r3,%r3 /* ok now to high priority, lets boot */
> - lis %r6,0x1
> - mtctr %r6 /* delay a bit for slaves to catch up */
> - bdnz . /* before we overwrite 0-100 again */
> -
> - bl 0f /* Work out where we're running */
> -0: mflr %r18
> -
> - /* load device-tree address */
> - ld %r3, (dt_offset - 0b)(%r18)
> - mr %r16,%r3 /* save dt address in reg16 */
> - li %r4,20
> - LWZX_BE %r6,%r3,%r4 /* fetch __be32 version number at byte 20 */
> - cmpwi %cr0,%r6,2 /* v2 or later? */
> - blt 1f
> - li %r4,28
> - STWX_BE %r17,%r3,%r4 /* Store my cpu as __be32 at byte 28 */
> -1:
> - /* load the kernel address */
> - ld %r4,(kernel - 0b)(%r18)
> -
> - /* load the run_at_load flag */
> - /* possibly patched by kexec */
> - ld %r6,(run_at_load - 0b)(%r18)
> - /* and patch it into the kernel */
> - stw %r6,(0x5c)(%r4)
> -
> - mr %r3,%r16 /* restore dt address */
> -
> - li %r5,0 /* r5 will be 0 for kernel */
> -
> - mfmsr %r11
> - andi. %r10,%r11,1 /* test MSR_LE */
> - bne .Little_endian
> -
> - mtctr %r4 /* prepare branch to */
> - bctr /* start kernel */
> -
> -.Little_endian:
> - mtsrr0 %r4 /* prepare branch to */
> -
> - clrrdi %r11,%r11,1 /* clear MSR_LE */
> - mtsrr1 %r11
> -
> - rfid /* update MSR and start kernel */
> -
> -
> - .balign 8
> - .globl kernel
> -kernel:
> - .8byte 0x0
> - .size kernel, . - kernel
> -
> - .balign 8
> - .globl dt_offset
> -dt_offset:
> - .8byte 0x0
> - .size dt_offset, . - dt_offset
> -
> -
> - .data
> - .balign 8
> -.globl purgatory_sha256_digest
> -purgatory_sha256_digest:
> - .skip 32
> - .size purgatory_sha256_digest, . - purgatory_sha256_digest
> -
> - .balign 8
> -.globl purgatory_sha_regions
> -purgatory_sha_regions:
> - .skip 8 * 2 * 16
> - .size purgatory_sha_regions, . - purgatory_sha_regions
> diff --git a/arch/powerpc/purgatory/trampoline_64.S b/arch/powerpc/purgatory/trampoline_64.S
> new file mode 100644
> index 0000000..a5a83c3
> --- /dev/null
> +++ b/arch/powerpc/purgatory/trampoline_64.S
> @@ -0,0 +1,117 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * kexec trampoline
> + *
> + * Based on code taken from kexec-tools and kexec-lite.
> + *
> + * Copyright (C) 2004 - 2005, Milton D Miller II, IBM Corporation
> + * Copyright (C) 2006, Mohan Kumar M, IBM Corporation
> + * Copyright (C) 2013, Anton Blanchard, IBM Corporation
> + */
> +
> +#include <asm/asm-compat.h>
> +
> + .machine ppc64
> + .balign 256
> + .globl purgatory_start
> +purgatory_start:
> + b master
> +
> + /* ABI: possible run_at_load flag at 0x5c */
> + .org purgatory_start + 0x5c
> + .globl run_at_load
> +run_at_load:
> + .long 0
> + .size run_at_load, . - run_at_load
> +
> + /* ABI: slaves start at 60 with r3=phys */
> + .org purgatory_start + 0x60
> +slave:
> + b .
> + /* ABI: end of copied region */
> + .org purgatory_start + 0x100
> + .size purgatory_start, . - purgatory_start
> +
> +/*
> + * The above 0x100 bytes at purgatory_start are replaced with the
> + * code from the kernel (or next stage) by setup_purgatory().
> + */
> +
> +master:
> + or %r1,%r1,%r1 /* low priority to let other threads catchup */
> + isync
> + mr %r17,%r3 /* save cpu id to r17 */
> + mr %r15,%r4 /* save physical address in reg15 */
> +
> + or %r3,%r3,%r3 /* ok now to high priority, lets boot */
> + lis %r6,0x1
> + mtctr %r6 /* delay a bit for slaves to catch up */
> + bdnz . /* before we overwrite 0-100 again */
> +
> + bl 0f /* Work out where we're running */
> +0: mflr %r18
> +
> + /* load device-tree address */
> + ld %r3, (dt_offset - 0b)(%r18)
> + mr %r16,%r3 /* save dt address in reg16 */
> + li %r4,20
> + LWZX_BE %r6,%r3,%r4 /* fetch __be32 version number at byte 20 */
> + cmpwi %cr0,%r6,2 /* v2 or later? */
> + blt 1f
> + li %r4,28
> + STWX_BE %r17,%r3,%r4 /* Store my cpu as __be32 at byte 28 */
> +1:
> + /* load the kernel address */
> + ld %r4,(kernel - 0b)(%r18)
> +
> + /* load the run_at_load flag */
> + /* possibly patched by kexec */
> + ld %r6,(run_at_load - 0b)(%r18)
> + /* and patch it into the kernel */
> + stw %r6,(0x5c)(%r4)
> +
> + mr %r3,%r16 /* restore dt address */
> +
> + li %r5,0 /* r5 will be 0 for kernel */
> +
> + mfmsr %r11
> + andi. %r10,%r11,1 /* test MSR_LE */
> + bne .Little_endian
> +
> + mtctr %r4 /* prepare branch to */
> + bctr /* start kernel */
> +
> +.Little_endian:
> + mtsrr0 %r4 /* prepare branch to */
> +
> + clrrdi %r11,%r11,1 /* clear MSR_LE */
> + mtsrr1 %r11
> +
> + rfid /* update MSR and start kernel */
> +
> +
> + .balign 8
> + .globl kernel
> +kernel:
> + .8byte 0x0
> + .size kernel, . - kernel
> +
> + .balign 8
> + .globl dt_offset
> +dt_offset:
> + .8byte 0x0
> + .size dt_offset, . - dt_offset
> +
> +
> + .data
> + .balign 8
> +.globl purgatory_sha256_digest
> +purgatory_sha256_digest:
> + .skip 32
> + .size purgatory_sha256_digest, . - purgatory_sha256_digest
> +
> + .balign 8
> +.globl purgatory_sha_regions
> +purgatory_sha_regions:
> + .skip 8 * 2 * 16
> + .size purgatory_sha_regions, . - purgatory_sha_regions
>
^ permalink raw reply [flat|nested] 16+ messages in thread
end of thread, other threads:[~2020-07-10 7:54 UTC | newest]
Thread overview: 16+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-07-02 19:53 [PATCH v2 00/12] ppc64: enable kdump support for kexec_file_load syscall Hari Bathini
2020-07-02 19:54 ` [PATCH v2 01/12] kexec_file: allow archs to handle special regions while locating memory hole Hari Bathini
2020-07-06 9:07 ` Dave Young
2020-07-02 19:54 ` [PATCH v2 02/12] powerpc/kexec_file: mark PPC64 specific code Hari Bathini
2020-07-10 7:52 ` Laurent Dufour
2020-07-02 19:54 ` [PATCH v2 03/12] powerpc/kexec_file: add helper functions for getting memory ranges Hari Bathini
2020-07-02 19:55 ` [PATCH v2 04/12] ppc64/kexec_file: avoid stomping memory used by special regions Hari Bathini
2020-07-02 19:55 ` [PATCH v2 05/12] powerpc/drmem: make lmb walk a bit more flexible Hari Bathini
2020-07-02 19:55 ` [PATCH v2 06/12] ppc64/kexec_file: restrict memory usage of kdump kernel Hari Bathini
2020-07-02 19:55 ` [PATCH v2 07/12] ppc64/kexec_file: add support to relocate purgatory Hari Bathini
2020-07-02 19:56 ` [PATCH v2 08/12] ppc64/kexec_file: setup the stack for purgatory Hari Bathini
2020-07-02 19:56 ` [PATCH v2 09/12] ppc64/kexec_file: setup backup region for kdump kernel Hari Bathini
2020-07-02 19:56 ` [PATCH v2 10/12] ppc64/kexec_file: prepare elfcore header for crashing kernel Hari Bathini
2020-07-02 19:56 ` [PATCH v2 11/12] ppc64/kexec_file: add appropriate regions for memory reserve map Hari Bathini
2020-07-02 19:57 ` [PATCH v2 12/12] ppc64/kexec_file: fix kexec load failure with lack of memory hole Hari Bathini
2020-07-07 0:43 ` [PATCH v2 00/12] ppc64: enable kdump support for kexec_file_load syscall piliu
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