Revision v7 of 6 in this series; 2 review trailers (1 from subsystem maintainers).

[PATCH v7 2/9] crash_core: fold duplicated memblock arch hooks into the weak default

From: Wandun Chen <hidden>
Date: 2026-09-22 08:43:44
Also in: kexec, linux-devicetree, linux-iommu, linux-mm, linux-riscv, lkml, loongarch
Subsystem: arm64 port (aarch64 architecture), kdump, loongarch, risc-v architecture, the rest · Maintainers: Catalin Marinas, Will Deacon, Andrew Morton, Baoquan He, Mike Rapoport, Pasha Tatashin, Pratyush Yadav, Huacai Chen, Paul Walmsley, Palmer Dabbelt, Albert Ou, Linus Torvalds

From: Wandun Chen <redacted>

arm64, loongarch and riscv open-code the same memblock walk in
arch_get_system_nr_ranges() and arch_crash_populate_cmem(). Move it into
the __weak defaults in kernel/crash_core.c and delete the arch copies.

No functional change.

Signed-off-by: Wandun Chen <redacted>
Tested-by: Meijing Zhao <redacted>
Acked-by: Baoquan He <baoquan.he@linux.dev>
---
 arch/arm64/kernel/machine_kexec_file.c     | 29 ----------------------
 arch/loongarch/kernel/machine_kexec_file.c | 27 --------------------
 arch/riscv/kernel/machine_kexec_file.c     | 26 -------------------
 kernel/crash_core.c                        | 25 +++++++++++++++++--
 4 files changed, 23 insertions(+), 84 deletions(-)

diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
index 854d872dfd0f..34d944d3f22f 100644
--- a/arch/arm64/kernel/machine_kexec_file.c
+++ b/arch/arm64/kernel/machine_kexec_file.c

@@ -14,7 +14,6 @@
 #include <linux/kernel.h>
 #include <linux/kexec.h>
 #include <linux/libfdt.h>
-#include <linux/memblock.h>
 #include <linux/of.h>
 #include <linux/of_fdt.h>
 #include <linux/slab.h>

@@ -39,34 +38,6 @@ int arch_kimage_file_post_load_cleanup(struct kimage *image)
 	return kexec_image_post_load_cleanup_default(image);
 }
 
-#ifdef CONFIG_CRASH_DUMP
-unsigned int arch_get_system_nr_ranges(void)
-{
-	unsigned int nr_ranges = 2 + crashk_cma_cnt; /* for exclusion of crashkernel region */
-	phys_addr_t start, end;
-	u64 i;
-
-	for_each_mem_range(i, &start, &end)
-		nr_ranges++;
-
-	return nr_ranges;
-}
-
-int arch_crash_populate_cmem(struct crash_mem *cmem)
-{
-	phys_addr_t start, end;
-	u64 i;
-
-	for_each_mem_range(i, &start, &end) {
-		cmem->ranges[cmem->nr_ranges].start = start;
-		cmem->ranges[cmem->nr_ranges].end = end - 1;
-		cmem->nr_ranges++;
-	}
-
-	return 0;
-}
-#endif
-
 /*
  * Tries to add the initrd and DTB to the image. If it is not possible to find
  * valid locations, this function will undo changes to the image and return non

diff --git a/arch/loongarch/kernel/machine_kexec_file.c b/arch/loongarch/kernel/machine_kexec_file.c
index 5412aa9f3568..481b8f906a56 100644
--- a/arch/loongarch/kernel/machine_kexec_file.c
+++ b/arch/loongarch/kernel/machine_kexec_file.c

@@ -13,7 +13,6 @@
 #include <linux/ioport.h>
 #include <linux/kernel.h>
 #include <linux/kexec.h>
-#include <linux/memblock.h>
 #include <linux/slab.h>
 #include <linux/string.h>
 #include <linux/types.h>

@@ -56,32 +55,6 @@ static void cmdline_add_initrd(struct kimage *image, unsigned long *cmdline_tmpl
 }
 
 #ifdef CONFIG_CRASH_DUMP
-unsigned int arch_get_system_nr_ranges(void)
-{
-	int nr_ranges = 2; /* for exclusion of crashkernel region */
-	phys_addr_t start, end;
-	uint64_t i;
-
-	for_each_mem_range(i, &start, &end)
-		nr_ranges++;
-
-	return nr_ranges;
-}
-
-int arch_crash_populate_cmem(struct crash_mem *cmem)
-{
-	phys_addr_t start, end;
-	uint64_t i;
-
-	for_each_mem_range(i, &start, &end) {
-		cmem->ranges[cmem->nr_ranges].start = start;
-		cmem->ranges[cmem->nr_ranges].end = end - 1;
-		cmem->nr_ranges++;
-	}
-
-	return 0;
-}
-
 /*
  * Add the "mem=size@start" command line parameter to command line, indicating the
  * memory region the new kernel can use to boot into.

diff --git a/arch/riscv/kernel/machine_kexec_file.c b/arch/riscv/kernel/machine_kexec_file.c
index 808e872f4063..fdc6695e8588 100644
--- a/arch/riscv/kernel/machine_kexec_file.c
+++ b/arch/riscv/kernel/machine_kexec_file.c

@@ -37,32 +37,6 @@ int arch_kimage_file_post_load_cleanup(struct kimage *image)
 }
 
 #ifdef CONFIG_CRASH_DUMP
-unsigned int arch_get_system_nr_ranges(void)
-{
-	unsigned int nr_ranges = 2 + crashk_cma_cnt; /* For exclusion of crashkernel region */
-	u64 i;
-	phys_addr_t start, end;
-
-	for_each_mem_range(i, &start, &end)
-		nr_ranges++;
-
-	return nr_ranges;
-}
-
-int arch_crash_populate_cmem(struct crash_mem *cmem)
-{
-	u64 i;
-	phys_addr_t start, end;
-
-	for_each_mem_range(i, &start, &end) {
-		cmem->ranges[cmem->nr_ranges].start = start;
-		cmem->ranges[cmem->nr_ranges].end = end - 1;
-		cmem->nr_ranges++;
-	}
-
-	return 0;
-}
-
 static char *setup_kdump_cmdline(struct kimage *image, char *cmdline,
 				 unsigned long cmdline_len)
 {

diff --git a/kernel/crash_core.c b/kernel/crash_core.c
index d0bd2d0cf899..d201638d11f3 100644
--- a/kernel/crash_core.c
+++ b/kernel/crash_core.c

@@ -281,8 +281,29 @@ static struct crash_mem *alloc_cmem(unsigned int nr_ranges)
 	return cmem;
 }
 
-unsigned int __weak arch_get_system_nr_ranges(void) { return 0; }
-int __weak arch_crash_populate_cmem(struct crash_mem *cmem) { return -1; }
+unsigned int __weak arch_get_system_nr_ranges(void)
+{
+	unsigned int nr_ranges = 2 + crashk_cma_cnt; /* crashk_res + crashk_low_res, +CMA splits */
+	phys_addr_t start, end;
+	u64 i;
+
+	for_each_mem_range(i, &start, &end)
+		nr_ranges++;
+	return nr_ranges;
+}
+
+int __weak arch_crash_populate_cmem(struct crash_mem *cmem)
+{
+	phys_addr_t start, end;
+	u64 i;
+
+	for_each_mem_range(i, &start, &end) {
+		cmem->ranges[cmem->nr_ranges].start = start;
+		cmem->ranges[cmem->nr_ranges].end = end - 1;
+		cmem->nr_ranges++;
+	}
+	return 0;
+}
 int __weak arch_crash_exclude_ranges(struct crash_mem *cmem) { return 0; }
 
 int __weak arch_crash_exclude_mem_range(struct crash_mem **mem,

-- 
2.43.0

`h`	back out one level
`j`	next message in thread
`k`	previous message in thread
`l`	drill in
`Esc`	close help / fold thread tree
`?`	toggle this help