Below error was noticed when running makedumpfile on linux-next kernel
crash (linux-next tag next-20240121):
...
Checking for memory holes : [100.0 %] | readpage_elf: Attempt to
read non-existent page at 0xc000000000000.
[ 17.551718] kdump.sh[404]: readmem: type_addr: 0,
addr:c00c000000000000, size:16384
[ 17.551793] kdump.sh[404]: __exclude_unnecessary_pages: Can't
read the buffer of struct page.
[ 17.551864] kdump.sh[404]: create_2nd_bitmap: Can't exclude
unnecessary pages.
[ 17.562632] kdump.sh[404]: The kernel version is not supported.
[ 17.562708] kdump.sh[404]: The makedumpfile operation may be
incomplete.
[ 17.562773] kdump.sh[404]: makedumpfile Failed.
[ 17.564335] kdump[406]: saving vmcore failed, _exitcode:1
Above error was due to 'vmap_area_list' and 'vmlist' symbols missing
from the vmcore.
'vmap_area_list' was removed in the linux kernel with below commit:
commit 378eb24a0658dd922b29524e0ce35c6c43f56cba
mm/vmalloc: remove vmap_area_list
Subsequently the commit also introduced 'VMALLOC_START' in vmcoreinfo to
get base address of vmalloc area, instead of depending on
'vmap_area_list'
Hence if 'VMALLOC_START' symbol is there in vmcoreinfo:
1. Set vmalloc_start based on 'VMALLOC_START'
2. Don't error if vmap_area_list/vmlist are not defined
Reported-by: Sachin Sant <sachinp@xxxxxxxxxxxxx>
Signed-off-by: Aditya Gupta <adityag@xxxxxxxxxxxxx>
---
arch/ppc64.c | 19 +++++++++++++------
makedumpfile.c | 3 ++-
makedumpfile.h | 6 +++---
3 files changed, 18 insertions(+), 10 deletions(-)
diff --git a/arch/ppc64.c b/arch/ppc64.c
index 96c357cb0335..bb62e2cd199a 100644
--- a/arch/ppc64.c
+++ b/arch/ppc64.c
@@ -568,7 +568,9 @@ get_machdep_info_ppc64(void)
/*
* Get vmalloc_start value from either vmap_area_list or vmlist.
*/
- if ((SYMBOL(vmap_area_list) != NOT_FOUND_SYMBOL)
+ if (NUMBER(vmalloc_start) != NOT_FOUND_SYMBOL) {
+ vmalloc_start = NUMBER(vmalloc_start);
+ } else if ((SYMBOL(vmap_area_list) != NOT_FOUND_SYMBOL)
&& (OFFSET(vmap_area.va_start) != NOT_FOUND_STRUCTURE)
&& (OFFSET(vmap_area.list) != NOT_FOUND_STRUCTURE)) {
if (!readmem(VADDR, SYMBOL(vmap_area_list) +
OFFSET(list_head.next),
@@ -684,11 +686,16 @@ vaddr_to_paddr_ppc64(unsigned long vaddr)
if ((SYMBOL(vmap_area_list) == NOT_FOUND_SYMBOL)
|| (OFFSET(vmap_area.va_start) == NOT_FOUND_STRUCTURE)
|| (OFFSET(vmap_area.list) == NOT_FOUND_STRUCTURE)) {
- if ((SYMBOL(vmlist) == NOT_FOUND_SYMBOL)
- || (OFFSET(vm_struct.addr) == NOT_FOUND_STRUCTURE)) {
- ERRMSG("Can't get info for vmalloc translation.\n");
- return NOT_PADDR;
- }
+ /*
+ * Don't depend on vmap_area_list/vmlist if vmalloc_start is
set in
+ * vmcoreinfo, in that case proceed without error
+ */
+ if (NUMBER(vmalloc_start) == NOT_FOUND_NUMBER)
+ if ((SYMBOL(vmlist) == NOT_FOUND_SYMBOL)
+ || (OFFSET(vm_struct.addr) == NOT_FOUND_STRUCTURE)) {
+ ERRMSG("Can't get info for vmalloc translation.\n");
+ return NOT_PADDR;
+ }
}
return ppc64_vtop_level4(vaddr);
diff --git a/makedumpfile.c b/makedumpfile.c
index b004b93fecb7..b6c63fad15f3 100644
--- a/makedumpfile.c
+++ b/makedumpfile.c
@@ -2978,6 +2978,8 @@ read_vmcoreinfo(void)
READ_NUMBER("PAGE_OFFLINE_MAPCOUNT_VALUE",
PAGE_OFFLINE_MAPCOUNT_VALUE);
READ_NUMBER("phys_base", phys_base);
READ_NUMBER("KERNEL_IMAGE_SIZE", KERNEL_IMAGE_SIZE);
+
+ READ_NUMBER_UNSIGNED("VMALLOC_START", vmalloc_start);
#ifdef __aarch64__
READ_NUMBER("VA_BITS", VA_BITS);
READ_NUMBER("TCR_EL1_T1SZ", TCR_EL1_T1SZ);
@@ -2989,7 +2991,6 @@ read_vmcoreinfo(void)
READ_NUMBER("VA_BITS", va_bits);
READ_NUMBER_UNSIGNED("phys_ram_base", phys_ram_base);
READ_NUMBER_UNSIGNED("PAGE_OFFSET", page_offset);
- READ_NUMBER_UNSIGNED("VMALLOC_START", vmalloc_start);
READ_NUMBER_UNSIGNED("VMALLOC_END", vmalloc_end);
READ_NUMBER_UNSIGNED("VMEMMAP_START", vmemmap_start);
READ_NUMBER_UNSIGNED("VMEMMAP_END", vmemmap_end);
diff --git a/makedumpfile.h b/makedumpfile.h
index 59c83e1d9df3..4021c5af2a34 100644
--- a/makedumpfile.h
+++ b/makedumpfile.h
@@ -541,8 +541,6 @@ do { \
* The value of dependence on machine
*/
#define PAGE_OFFSET (info->page_offset)
-#define VMALLOC_START (info->vmalloc_start)
-#define VMALLOC_END (info->vmalloc_end)
#define VMEMMAP_START (info->vmemmap_start)
#define VMEMMAP_END (info->vmemmap_end)
#define PMASK (0x7ffffffffffff000UL)
@@ -2262,6 +2260,9 @@ struct number_table {
long HUGETLB_PAGE_DTOR;
long phys_base;
long KERNEL_IMAGE_SIZE;
+
+ unsigned long vmalloc_start;
+
#ifdef __aarch64__
long VA_BITS;
long TCR_EL1_T1SZ;
@@ -2272,7 +2273,6 @@ struct number_table {
long va_bits;
unsigned long phys_ram_base;
unsigned long page_offset;
- unsigned long vmalloc_start;
unsigned long vmalloc_end;
unsigned long vmemmap_start;
unsigned long vmemmap_end;
