diff options
| -rw-r--r-- | Documentation/filesystems/proc.txt | 22 | ||||
| -rw-r--r-- | fs/binfmt_elf.c | 10 | ||||
| -rw-r--r-- | include/linux/sched.h | 4 |
3 files changed, 25 insertions, 11 deletions
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index d411ca63c8b6..6f887cf873a1 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -1598,16 +1598,16 @@ Documentation/accounting. --------------------------------------------------------------- When a process is dumped, all anonymous memory is written to a core file as long as the size of the core file isn't limited. But sometimes we don't want -to dump some memory segments, for example, huge shared memory. Conversely, -sometimes we want to save file-backed memory segments into a core file, not -only the individual files. +to dump some memory segments, for example, huge shared memory or DAX. +Conversely, sometimes we want to save file-backed memory segments into a core +file, not only the individual files. /proc/<pid>/coredump_filter allows you to customize which memory segments 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 7 memory types are supported: +The following 9 memory types are supported: - (bit 0) anonymous private memory - (bit 1) anonymous shared memory - (bit 2) file-backed private memory @@ -1616,20 +1616,22 @@ The following 7 memory types are supported: effective only if the bit 2 is cleared) - (bit 5) hugetlb private memory - (bit 6) hugetlb shared memory + - (bit 7) DAX private memory + - (bit 8) DAX shared memory Note that MMIO pages such as frame buffer are never dumped and vDSO pages are always dumped regardless of the bitmask status. - Note bit 0-4 doesn't effect any hugetlb memory. hugetlb memory are only - effected by bit 5-6. + Note that bits 0-4 don't affect hugetlb or DAX memory. hugetlb memory is + only affected by bit 5-6, and DAX is only affected by bits 7-8. -Default value of coredump_filter is 0x23; this means all anonymous memory -segments and hugetlb private memory are dumped. +The default value of coredump_filter is 0x33; this means all anonymous memory +segments, ELF header pages and hugetlb private memory are dumped. If you don't want to dump all shared memory segments attached to pid 1234, -write 0x21 to the process's proc file. +write 0x31 to the process's proc file. - $ echo 0x21 > /proc/1234/coredump_filter + $ echo 0x31 > /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 6b659967898e..5f399ea1d20a 100644 --- a/fs/binfmt_elf.c +++ b/fs/binfmt_elf.c @@ -35,6 +35,7 @@ #include <linux/utsname.h> #include <linux/coredump.h> #include <linux/sched.h> +#include <linux/dax.h> #include <asm/uaccess.h> #include <asm/param.h> #include <asm/page.h> @@ -1236,6 +1237,15 @@ static unsigned long vma_dump_size(struct vm_area_struct *vma, if (vma->vm_flags & VM_DONTDUMP) return 0; + /* support for DAX */ + if (vma_is_dax(vma)) { + if ((vma->vm_flags & VM_SHARED) && FILTER(DAX_SHARED)) + goto whole; + if (!(vma->vm_flags & VM_SHARED) && FILTER(DAX_PRIVATE)) + goto whole; + return 0; + } + /* Hugetlb memory check */ if (vma->vm_flags & VM_HUGETLB) { if ((vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_SHARED)) diff --git a/include/linux/sched.h b/include/linux/sched.h index b7b9501b41af..3c02d92ed23b 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -483,9 +483,11 @@ static inline int get_dumpable(struct mm_struct *mm) #define MMF_DUMP_ELF_HEADERS 6 #define MMF_DUMP_HUGETLB_PRIVATE 7 #define MMF_DUMP_HUGETLB_SHARED 8 +#define MMF_DUMP_DAX_PRIVATE 9 +#define MMF_DUMP_DAX_SHARED 10 #define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS -#define MMF_DUMP_FILTER_BITS 7 +#define MMF_DUMP_FILTER_BITS 9 #define MMF_DUMP_FILTER_MASK \ (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT) #define MMF_DUMP_FILTER_DEFAULT \ |