When load the kernel image and initramfs by kexec_file_load syscall, it can
not add exact e820 reserved type to kdump kernel e820 table.
Kdump uses walk_iomem_res_desc() to iterate io resources, then adds matched
desc to e820 table for kdump kernel. But, when convert the e820 type into
the iores descriptors, several e820 types are converted to 'IORES_DES_NONE'
in this function e820_type_to_iores_desc(). So the walk_iomem_res_desc()
will get these unnecessary types(E820_TYPE_RAM/E820_TYPE_UNUSABLE/E820_TYPE
_KERN) when iterate io resources by the 'IORES_DES_NONE'.
It needs filter out these redundant type(such as E820_TYPE_RAM/E820_TYPE_
UNUSABLE/E820_TYPE_KERN) in order to add exact e820 reserved type to kdump
kernel e820 table. Thus it also needs an extra checking in memmap_entry_
callback() to match the e820 type and resource name.
Suggested-by: Dave Young <dyoung@xxxxxxxxxx>
Signed-off-by: Lianbo Jiang <lijiang@xxxxxxxxxx>
---
Changes since v5:
1. Improve the patch log
arch/x86/include/asm/e820/api.h | 2 ++
arch/x86/kernel/crash.c | 6 +++++-
arch/x86/kernel/e820.c | 2 +-
kernel/resource.c | 1 +
4 files changed, 9 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/e820/api.h b/arch/x86/include/asm/e820/api.h
index 62be73b23d5c..6d5451b36e80 100644
--- a/arch/x86/include/asm/e820/api.h
+++ b/arch/x86/include/asm/e820/api.h
@@ -42,6 +42,8 @@ extern void e820__register_nosave_regions(unsigned long limit_pfn);
extern int e820__get_entry_type(u64 start, u64 end);
+extern const char *e820_type_to_string(struct e820_entry *entry);
+
/*
* Returns true iff the specified range [start,end) is completely contained inside
* the ISA region.
diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c
index f631a3f15587..ae724a6e0a5f 100644
--- a/arch/x86/kernel/crash.c
+++ b/arch/x86/kernel/crash.c
@@ -37,6 +37,7 @@
#include <asm/reboot.h>
#include <asm/virtext.h>
#include <asm/intel_pt.h>
+#include <asm/e820/api.h>
/* Used while preparing memory map entries for second kernel */
struct crash_memmap_data {
@@ -314,11 +315,14 @@ static int memmap_entry_callback(struct resource *res, void *arg)
struct crash_memmap_data *cmd = arg;
struct boot_params *params = cmd->params;
struct e820_entry ei;
+ const char *name;
ei.addr = res->start;
ei.size = resource_size(res);
ei.type = cmd->type;
- add_e820_entry(params, &ei);
+ name = e820_type_to_string(&ei);
+ if (res->name && !strcmp(name, res->name))
+ add_e820_entry(params, &ei);
return 0;
}
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index 50895c2f937d..4c1fe4f8db1e 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -1011,7 +1011,7 @@ void __init e820__finish_early_params(void)
}
}
-static const char *__init e820_type_to_string(struct e820_entry *entry)
+const char *e820_type_to_string(struct e820_entry *entry)
{
switch (entry->type) {
case E820_TYPE_RESERVED_KERN: /* Fall-through: */
diff --git a/kernel/resource.c b/kernel/resource.c
index b0fbf685c77a..4ac07717e2b1 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -373,6 +373,7 @@ static int find_next_iomem_res(resource_size_t start, resource_size_t end,
res->end = min(end, p->end);
res->flags = p->flags;
res->desc = p->desc;
+ res->name = p->name;
return 0;
}
--
2.17.1
_______________________________________________
kexec mailing list
kexec@xxxxxxxxxxxxxxxxxxx
http://lists.infradead.org/mailman/listinfo/kexec
