Subject: + vmcore-allocate-buffer-for-elf-headers-on-page-size-alignment.patch added to -mm tree
To: d.hatayama@xxxxxxxxxxxxxx,kosaki.motohiro@xxxxxxxxxxxxxx,kumagai-atsushi@xxxxxxxxxxxxxxxxx,lisa.mitchell@xxxxxx,vgoyal@xxxxxxxxxx,zhangyanfei@xxxxxxxxxxxxxx
From: akpm@xxxxxxxxxxxxxxxxxxxx
Date: Thu, 23 May 2013 15:25:01 -0700
The patch titled
Subject: vmcore: allocate buffer for ELF headers on page-size alignment
has been added to the -mm tree. Its filename is
vmcore-allocate-buffer-for-elf-headers-on-page-size-alignment.patch
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*** Remember to use Documentation/SubmitChecklist when testing your code ***
The -mm tree is included into linux-next and is updated
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------------------------------------------------------
From: HATAYAMA Daisuke <d.hatayama@xxxxxxxxxxxxxx>
Subject: vmcore: allocate buffer for ELF headers on page-size alignment
Allocate ELF headers on page-size boundary using __get_free_pages()
instead of kmalloc().
Later patch will merge PT_NOTE entries into a single unique one and
decrease the buffer size actually used. Keep original buffer size in
variable elfcorebuf_sz_orig to kfree the buffer later and actually used
buffer size with rounded up to page-size boundary in variable
elfcorebuf_sz separately.
The size of part of the ELF buffer exported from /proc/vmcore is
elfcorebuf_sz.
The merged, removed PT_NOTE entries, i.e. the range [elfcorebuf_sz,
elfcorebuf_sz_orig], is filled with 0.
Use size of the ELF headers as an initial offset value in
set_vmcore_list_offsets_elf{64,32} and
process_ptload_program_headers_elf{64,32} in order to indicate that the
offset includes the holes towards the page boundary.
As a result, both set_vmcore_list_offsets_elf{64,32} have the same
definition. Merge them as set_vmcore_list_offsets.
Signed-off-by: HATAYAMA Daisuke <d.hatayama@xxxxxxxxxxxxxx>
Acked-by: Vivek Goyal <vgoyal@xxxxxxxxxx>
Cc: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
Cc: Atsushi Kumagai <kumagai-atsushi@xxxxxxxxxxxxxxxxx>
Cc: Lisa Mitchell <lisa.mitchell@xxxxxx>
Cc: Zhang Yanfei <zhangyanfei@xxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/proc/vmcore.c | 94 ++++++++++++++++++++-------------------------
1 file changed, 42 insertions(+), 52 deletions(-)
diff -puN fs/proc/vmcore.c~vmcore-allocate-buffer-for-elf-headers-on-page-size-alignment fs/proc/vmcore.c
--- a/fs/proc/vmcore.c~vmcore-allocate-buffer-for-elf-headers-on-page-size-alignment
+++ a/fs/proc/vmcore.c
@@ -32,6 +32,7 @@ static LIST_HEAD(vmcore_list);
/* Stores the pointer to the buffer containing kernel elf core headers. */
static char *elfcorebuf;
static size_t elfcorebuf_sz;
+static size_t elfcorebuf_sz_orig;
/* Total size of vmcore file. */
static u64 vmcore_size;
@@ -186,7 +187,7 @@ static struct vmcore* __init get_new_ele
return kzalloc(sizeof(struct vmcore), GFP_KERNEL);
}
-static u64 __init get_vmcore_size_elf64(char *elfptr)
+static u64 __init get_vmcore_size_elf64(char *elfptr, size_t elfsz)
{
int i;
u64 size;
@@ -195,7 +196,7 @@ static u64 __init get_vmcore_size_elf64(
ehdr_ptr = (Elf64_Ehdr *)elfptr;
phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr));
- size = sizeof(Elf64_Ehdr) + ((ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr));
+ size = elfsz;
for (i = 0; i < ehdr_ptr->e_phnum; i++) {
size += phdr_ptr->p_memsz;
phdr_ptr++;
@@ -203,7 +204,7 @@ static u64 __init get_vmcore_size_elf64(
return size;
}
-static u64 __init get_vmcore_size_elf32(char *elfptr)
+static u64 __init get_vmcore_size_elf32(char *elfptr, size_t elfsz)
{
int i;
u64 size;
@@ -212,7 +213,7 @@ static u64 __init get_vmcore_size_elf32(
ehdr_ptr = (Elf32_Ehdr *)elfptr;
phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr));
- size = sizeof(Elf32_Ehdr) + ((ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr));
+ size = elfsz;
for (i = 0; i < ehdr_ptr->e_phnum; i++) {
size += phdr_ptr->p_memsz;
phdr_ptr++;
@@ -294,6 +295,8 @@ static int __init merge_note_headers_elf
i = (nr_ptnote - 1) * sizeof(Elf64_Phdr);
*elfsz = *elfsz - i;
memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf64_Ehdr)-sizeof(Elf64_Phdr)));
+ memset(elfptr + *elfsz, 0, i);
+ *elfsz = roundup(*elfsz, PAGE_SIZE);
/* Modify e_phnum to reflect merged headers. */
ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1;
@@ -375,6 +378,8 @@ static int __init merge_note_headers_elf
i = (nr_ptnote - 1) * sizeof(Elf32_Phdr);
*elfsz = *elfsz - i;
memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf32_Ehdr)-sizeof(Elf32_Phdr)));
+ memset(elfptr + *elfsz, 0, i);
+ *elfsz = roundup(*elfsz, PAGE_SIZE);
/* Modify e_phnum to reflect merged headers. */
ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1;
@@ -398,8 +403,7 @@ static int __init process_ptload_program
phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr)); /* PT_NOTE hdr */
/* First program header is PT_NOTE header. */
- vmcore_off = sizeof(Elf64_Ehdr) +
- (ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr) +
+ vmcore_off = elfsz +
phdr_ptr->p_memsz; /* Note sections */
for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
@@ -435,8 +439,7 @@ static int __init process_ptload_program
phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr)); /* PT_NOTE hdr */
/* First program header is PT_NOTE header. */
- vmcore_off = sizeof(Elf32_Ehdr) +
- (ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr) +
+ vmcore_off = elfsz +
phdr_ptr->p_memsz; /* Note sections */
for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
@@ -459,38 +462,14 @@ static int __init process_ptload_program
}
/* Sets offset fields of vmcore elements. */
-static void __init set_vmcore_list_offsets_elf64(char *elfptr,
- struct list_head *vc_list)
+static void __init set_vmcore_list_offsets(size_t elfsz,
+ struct list_head *vc_list)
{
loff_t vmcore_off;
- Elf64_Ehdr *ehdr_ptr;
struct vmcore *m;
- ehdr_ptr = (Elf64_Ehdr *)elfptr;
-
- /* Skip Elf header and program headers. */
- vmcore_off = sizeof(Elf64_Ehdr) +
- (ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr);
-
- list_for_each_entry(m, vc_list, list) {
- m->offset = vmcore_off;
- vmcore_off += m->size;
- }
-}
-
-/* Sets offset fields of vmcore elements. */
-static void __init set_vmcore_list_offsets_elf32(char *elfptr,
- struct list_head *vc_list)
-{
- loff_t vmcore_off;
- Elf32_Ehdr *ehdr_ptr;
- struct vmcore *m;
-
- ehdr_ptr = (Elf32_Ehdr *)elfptr;
-
/* Skip Elf header and program headers. */
- vmcore_off = sizeof(Elf32_Ehdr) +
- (ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr);
+ vmcore_off = elfsz;
list_for_each_entry(m, vc_list, list) {
m->offset = vmcore_off;
@@ -526,30 +505,35 @@ static int __init parse_crash_elf64_head
}
/* Read in all elf headers. */
- elfcorebuf_sz = sizeof(Elf64_Ehdr) + ehdr.e_phnum * sizeof(Elf64_Phdr);
- elfcorebuf = kmalloc(elfcorebuf_sz, GFP_KERNEL);
+ elfcorebuf_sz_orig = sizeof(Elf64_Ehdr) + ehdr.e_phnum * sizeof(Elf64_Phdr);
+ elfcorebuf_sz = elfcorebuf_sz_orig;
+ elfcorebuf = (void *) __get_free_pages(GFP_KERNEL | __GFP_ZERO,
+ get_order(elfcorebuf_sz_orig));
if (!elfcorebuf)
return -ENOMEM;
addr = elfcorehdr_addr;
- rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz, &addr, 0);
+ rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz_orig, &addr, 0);
if (rc < 0) {
- kfree(elfcorebuf);
+ free_pages((unsigned long)elfcorebuf,
+ get_order(elfcorebuf_sz_orig));
return rc;
}
/* Merge all PT_NOTE headers into one. */
rc = merge_note_headers_elf64(elfcorebuf, &elfcorebuf_sz, &vmcore_list);
if (rc) {
- kfree(elfcorebuf);
+ free_pages((unsigned long)elfcorebuf,
+ get_order(elfcorebuf_sz_orig));
return rc;
}
rc = process_ptload_program_headers_elf64(elfcorebuf, elfcorebuf_sz,
&vmcore_list);
if (rc) {
- kfree(elfcorebuf);
+ free_pages((unsigned long)elfcorebuf,
+ get_order(elfcorebuf_sz_orig));
return rc;
}
- set_vmcore_list_offsets_elf64(elfcorebuf, &vmcore_list);
+ set_vmcore_list_offsets(elfcorebuf_sz, &vmcore_list);
return 0;
}
@@ -581,30 +565,35 @@ static int __init parse_crash_elf32_head
}
/* Read in all elf headers. */
- elfcorebuf_sz = sizeof(Elf32_Ehdr) + ehdr.e_phnum * sizeof(Elf32_Phdr);
- elfcorebuf = kmalloc(elfcorebuf_sz, GFP_KERNEL);
+ elfcorebuf_sz_orig = sizeof(Elf32_Ehdr) + ehdr.e_phnum * sizeof(Elf32_Phdr);
+ elfcorebuf_sz = elfcorebuf_sz_orig;
+ elfcorebuf = (void *) __get_free_pages(GFP_KERNEL | __GFP_ZERO,
+ get_order(elfcorebuf_sz_orig));
if (!elfcorebuf)
return -ENOMEM;
addr = elfcorehdr_addr;
- rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz, &addr, 0);
+ rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz_orig, &addr, 0);
if (rc < 0) {
- kfree(elfcorebuf);
+ free_pages((unsigned long)elfcorebuf,
+ get_order(elfcorebuf_sz_orig));
return rc;
}
/* Merge all PT_NOTE headers into one. */
rc = merge_note_headers_elf32(elfcorebuf, &elfcorebuf_sz, &vmcore_list);
if (rc) {
- kfree(elfcorebuf);
+ free_pages((unsigned long)elfcorebuf,
+ get_order(elfcorebuf_sz_orig));
return rc;
}
rc = process_ptload_program_headers_elf32(elfcorebuf, elfcorebuf_sz,
&vmcore_list);
if (rc) {
- kfree(elfcorebuf);
+ free_pages((unsigned long)elfcorebuf,
+ get_order(elfcorebuf_sz_orig));
return rc;
}
- set_vmcore_list_offsets_elf32(elfcorebuf, &vmcore_list);
+ set_vmcore_list_offsets(elfcorebuf_sz, &vmcore_list);
return 0;
}
@@ -629,14 +618,14 @@ static int __init parse_crash_elf_header
return rc;
/* Determine vmcore size. */
- vmcore_size = get_vmcore_size_elf64(elfcorebuf);
+ vmcore_size = get_vmcore_size_elf64(elfcorebuf, elfcorebuf_sz);
} else if (e_ident[EI_CLASS] == ELFCLASS32) {
rc = parse_crash_elf32_headers();
if (rc)
return rc;
/* Determine vmcore size. */
- vmcore_size = get_vmcore_size_elf32(elfcorebuf);
+ vmcore_size = get_vmcore_size_elf32(elfcorebuf, elfcorebuf_sz);
} else {
pr_warn("Warning: Core image elf header is not sane\n");
return -EINVAL;
@@ -683,7 +672,8 @@ void vmcore_cleanup(void)
list_del(&m->list);
kfree(m);
}
- kfree(elfcorebuf);
+ free_pages((unsigned long)elfcorebuf,
+ get_order(elfcorebuf_sz_orig));
elfcorebuf = NULL;
}
EXPORT_SYMBOL_GPL(vmcore_cleanup);
_
Patches currently in -mm which might be from d.hatayama@xxxxxxxxxxxxxx are
include-linux-mmh-add-page_aligned-helper.patch
vmcore-clean-up-read_vmcore.patch
vmcore-allocate-buffer-for-elf-headers-on-page-size-alignment.patch
vmcore-allocate-buffer-for-elf-headers-on-page-size-alignment-fix.patch
vmcore-treat-memory-chunks-referenced-by-pt_load-program-header-entries-in-page-size-boundary-in-vmcore_list.patch
vmalloc-make-find_vm_area-check-in-range.patch
vmalloc-introduce-remap_vmalloc_range_partial.patch
vmalloc-introduce-remap_vmalloc_range_partial-fix.patch
vmcore-allocate-elf-note-segment-in-the-2nd-kernel-vmalloc-memory.patch
vmcore-allocate-elf-note-segment-in-the-2nd-kernel-vmalloc-memory-fix.patch
vmcore-allow-user-process-to-remap-elf-note-segment-buffer.patch
vmcore-allow-user-process-to-remap-elf-note-segment-buffer-fix.patch
vmcore-calculate-vmcore-file-size-from-buffer-size-and-total-size-of-vmcore-objects.patch
vmcore-support-mmap-on-proc-vmcore.patch
vmcore-support-mmap-on-proc-vmcore-fix.patch
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