diff options
| author | Jan Kara <jack@suse.cz> | 2018-10-09 12:19:17 +0200 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2018-10-09 11:44:58 -0700 |
| commit | 4628a64591e6cee181237060961e98c615c33966 (patch) | |
| tree | e838aba36f4d6dfaa70a3db24590b58269b6dc18 /arch/powerpc | |
| parent | d7782145e1ad537df4ce74e58c50f1f732a1462d (diff) | |
mm: Preserve _PAGE_DEVMAP across mprotect() calls
Currently _PAGE_DEVMAP bit is not preserved in mprotect(2) calls. As a
result we will see warnings such as:
BUG: Bad page map in process JobWrk0013 pte:800001803875ea25 pmd:7624381067
addr:00007f0930720000 vm_flags:280000f9 anon_vma: (null) mapping:ffff97f2384056f0 index:0
file:457-000000fe00000030-00000009-000000ca-00000001_2001.fileblock fault:xfs_filemap_fault [xfs] mmap:xfs_file_mmap [xfs] readpage: (null)
CPU: 3 PID: 15848 Comm: JobWrk0013 Tainted: G W 4.12.14-2.g7573215-default #1 SLE12-SP4 (unreleased)
Hardware name: Intel Corporation S2600WFD/S2600WFD, BIOS SE5C620.86B.01.00.0833.051120182255 05/11/2018
Call Trace:
dump_stack+0x5a/0x75
print_bad_pte+0x217/0x2c0
? enqueue_task_fair+0x76/0x9f0
_vm_normal_page+0xe5/0x100
zap_pte_range+0x148/0x740
unmap_page_range+0x39a/0x4b0
unmap_vmas+0x42/0x90
unmap_region+0x99/0xf0
? vma_gap_callbacks_rotate+0x1a/0x20
do_munmap+0x255/0x3a0
vm_munmap+0x54/0x80
SyS_munmap+0x1d/0x30
do_syscall_64+0x74/0x150
entry_SYSCALL_64_after_hwframe+0x3d/0xa2
...
when mprotect(2) gets used on DAX mappings. Also there is a wide variety
of other failures that can result from the missing _PAGE_DEVMAP flag
when the area gets used by get_user_pages() later.
Fix the problem by including _PAGE_DEVMAP in a set of flags that get
preserved by mprotect(2).
Fixes: 69660fd797c3 ("x86, mm: introduce _PAGE_DEVMAP")
Fixes: ebd31197931d ("powerpc/mm: Add devmap support for ppc64")
Cc: <stable@vger.kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'arch/powerpc')
| -rw-r--r-- | arch/powerpc/include/asm/book3s/64/pgtable.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h index 2fdc865ca374..2a2486526d1f 100644 --- a/arch/powerpc/include/asm/book3s/64/pgtable.h +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h @@ -114,7 +114,7 @@ */ #define _HPAGE_CHG_MASK (PTE_RPN_MASK | _PAGE_HPTEFLAGS | _PAGE_DIRTY | \ _PAGE_ACCESSED | H_PAGE_THP_HUGE | _PAGE_PTE | \ - _PAGE_SOFT_DIRTY) + _PAGE_SOFT_DIRTY | _PAGE_DEVMAP) /* * user access blocked by key */ @@ -132,7 +132,7 @@ */ #define _PAGE_CHG_MASK (PTE_RPN_MASK | _PAGE_HPTEFLAGS | _PAGE_DIRTY | \ _PAGE_ACCESSED | _PAGE_SPECIAL | _PAGE_PTE | \ - _PAGE_SOFT_DIRTY) + _PAGE_SOFT_DIRTY | _PAGE_DEVMAP) #define H_PTE_PKEY (H_PTE_PKEY_BIT0 | H_PTE_PKEY_BIT1 | H_PTE_PKEY_BIT2 | \ H_PTE_PKEY_BIT3 | H_PTE_PKEY_BIT4) |