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-rw-r--r--Documentation/filesystems/proc.txt15
-rw-r--r--fs/binfmt_elf.c12
-rw-r--r--include/linux/sched.h7
3 files changed, 25 insertions, 9 deletions
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index c032bf39e8b..02cb7faeed6 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -2412,24 +2412,29 @@ will be dumped when the <pid> process is dumped. coredump_filter is a bitmask
of memory types. If a bit of the bitmask is set, memory segments of the
corresponding memory type are dumped, otherwise they are not dumped.
-The following 4 memory types are supported:
+The following 7 memory types are supported:
- (bit 0) anonymous private memory
- (bit 1) anonymous shared memory
- (bit 2) file-backed private memory
- (bit 3) file-backed shared memory
- (bit 4) ELF header pages in file-backed private memory areas (it is
effective only if the bit 2 is cleared)
+ - (bit 5) hugetlb private memory
+ - (bit 6) hugetlb shared memory
Note that MMIO pages such as frame buffer are never dumped and vDSO pages
are always dumped regardless of the bitmask status.
-Default value of coredump_filter is 0x3; this means all anonymous memory
-segments are dumped.
+ Note bit 0-4 doesn't effect any hugetlb memory. hugetlb memory are only
+ effected by bit 5-6.
+
+Default value of coredump_filter is 0x23; this means all anonymous memory
+segments and hugetlb private memory are dumped.
If you don't want to dump all shared memory segments attached to pid 1234,
-write 1 to the process's proc file.
+write 0x21 to the process's proc file.
- $ echo 0x1 > /proc/1234/coredump_filter
+ $ echo 0x21 > /proc/1234/coredump_filter
When a new process is created, the process inherits the bitmask status from its
parent. It is useful to set up coredump_filter before the program runs.
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index c76afa26edf..e2159063198 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -1156,16 +1156,24 @@ static int dump_seek(struct file *file, loff_t off)
static unsigned long vma_dump_size(struct vm_area_struct *vma,
unsigned long mm_flags)
{
+#define FILTER(type) (mm_flags & (1UL << MMF_DUMP_##type))
+
/* The vma can be set up to tell us the answer directly. */
if (vma->vm_flags & VM_ALWAYSDUMP)
goto whole;
+ /* Hugetlb memory check */
+ if (vma->vm_flags & VM_HUGETLB) {
+ if ((vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_SHARED))
+ goto whole;
+ if (!(vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_PRIVATE))
+ goto whole;
+ }
+
/* Do not dump I/O mapped devices or special mappings */
if (vma->vm_flags & (VM_IO | VM_RESERVED))
return 0;
-#define FILTER(type) (mm_flags & (1UL << MMF_DUMP_##type))
-
/* By default, dump shared memory if mapped from an anonymous file. */
if (vma->vm_flags & VM_SHARED) {
if (vma->vm_file->f_path.dentry->d_inode->i_nlink == 0 ?
diff --git a/include/linux/sched.h b/include/linux/sched.h
index c226c7b8294..017cc914ef1 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -403,12 +403,15 @@ extern int get_dumpable(struct mm_struct *mm);
#define MMF_DUMP_MAPPED_PRIVATE 4
#define MMF_DUMP_MAPPED_SHARED 5
#define MMF_DUMP_ELF_HEADERS 6
+#define MMF_DUMP_HUGETLB_PRIVATE 7
+#define MMF_DUMP_HUGETLB_SHARED 8
#define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS
-#define MMF_DUMP_FILTER_BITS 5
+#define MMF_DUMP_FILTER_BITS 7
#define MMF_DUMP_FILTER_MASK \
(((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
#define MMF_DUMP_FILTER_DEFAULT \
- ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED))
+ ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\
+ (1 << MMF_DUMP_HUGETLB_PRIVATE))
struct sighand_struct {
atomic_t count;