From: Coiby Xu Subject: [PATCH] ppc64: get vmalloc start address from vmcoreinfo Bugzilla: https://bugzilla.redhat.com/2269991 commit 94241fd2feed059227a243618f2acc6aabf366e8 Author: Aditya Gupta Date: Sat Feb 24 00:33:42 2024 +0530 [PATCH] ppc64: get vmalloc start address from vmcoreinfo 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 6.9-rc1 by the commit below: commit 55c49fee57af99f3c663e69dedc5b85e691bbe50 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 Signed-off-by: Aditya Gupta Signed-off-by: Coiby Xu diff --git a/makedumpfile-1.7.4/arch/ppc64.c b/makedumpfile-1.7.4/arch/ppc64.c index 3b4f91981f71d035b94282f6c7e33323a4e4c1fd..a54f9a04db7f26eac2f1bd065b134a7e2fdaeb67 100644 --- a/makedumpfile-1.7.4/arch/ppc64.c +++ b/makedumpfile-1.7.4/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_NUMBER) { + 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), @@ -689,11 +691,16 @@ 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-1.7.4/makedumpfile.c b/makedumpfile-1.7.4/makedumpfile.c index 58c6639f289f19cdbf39ed3899be9893fdc317fe..d7f1dd41d2cab526d7d40e809ddccf656c586811 100644 --- a/makedumpfile-1.7.4/makedumpfile.c +++ b/makedumpfile-1.7.4/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-1.7.4/makedumpfile.h b/makedumpfile-1.7.4/makedumpfile.h index c04c330b69ecbe5fb232a2eabbd2d71f14b60cc0..c31f3a4371af8aae38dcba8cac4d6de1012b4cfd 100644 --- a/makedumpfile-1.7.4/makedumpfile.h +++ b/makedumpfile-1.7.4/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) @@ -2263,6 +2261,9 @@ 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; @@ -2273,7 +2274,6 @@ 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;