diff options
| author | Kirill A. Shutemov <[email protected]> | 2015-11-30 11:10:33 +0100 |
|---|---|---|
| committer | Ingo Molnar <[email protected]> | 2015-12-04 09:14:27 +0100 |
| commit | 70f1528747651b20c7769d3516ade369f9963237 (patch) | |
| tree | cb16ea89652a77eceec7947d05607f39b42681f7 /net/lapb/lapb_iface.c | |
| parent | 656279a1f3b210cf48ccc572fd7c6b8e2250be77 (diff) | |
x86/mm: Fix regression with huge pages on PAE
Recent PAT patchset has caused issue on 32-bit PAE machines:
page:eea45000 count:0 mapcount:-128 mapping: (null) index:0x0 flags: 0x40000000()
page dumped because: VM_BUG_ON_PAGE(page_mapcount(page) < 0)
------------[ cut here ]------------
kernel BUG at /home/build/linux-boris/mm/huge_memory.c:1485!
invalid opcode: 0000 [#1] SMP
[...]
Call Trace:
unmap_single_vma
? __wake_up
unmap_vmas
unmap_region
do_munmap
vm_munmap
SyS_munmap
do_fast_syscall_32
? __do_page_fault
sysenter_past_esp
Code: ...
EIP: [<c11bde80>] zap_huge_pmd+0x240/0x260 SS:ESP 0068:f6459d98
The problem is in pmd_pfn_mask() and pmd_flags_mask(). These
helpers use PMD_PAGE_MASK to calculate resulting mask.
PMD_PAGE_MASK is 'unsigned long', not 'unsigned long long' as
phys_addr_t is on 32-bit PAE (ARCH_PHYS_ADDR_T_64BIT). As a
result, the upper bits of resulting mask get truncated.
pud_pfn_mask() and pud_flags_mask() aren't problematic since we
don't have PUD page table level on 32-bit systems, but it's
reasonable to keep them consistent with PMD counterpart.
Introduce PHYSICAL_PMD_PAGE_MASK and PHYSICAL_PUD_PAGE_MASK in
addition to existing PHYSICAL_PAGE_MASK and reworks helpers to
use them.
Reported-and-Tested-by: Boris Ostrovsky <[email protected]>
Signed-off-by: Kirill A. Shutemov <[email protected]>
[ Fix -Woverflow warnings from the realmode code. ]
Signed-off-by: Borislav Petkov <[email protected]>
Reviewed-by: Toshi Kani <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Brian Gerst <[email protected]>
Cc: Denys Vlasenko <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Jürgen Gross <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Mel Gorman <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: linux-mm <[email protected]>
Fixes: f70abb0fc3da ("x86/asm: Fix pud/pmd interfaces to handle large PAT bit")
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Diffstat (limited to 'net/lapb/lapb_iface.c')
0 files changed, 0 insertions, 0 deletions