diff options
| author | Ingo Molnar <mingo@kernel.org> | 2017-10-27 10:03:13 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-10-27 10:06:49 +0200 |
| commit | 90edaac62729d3b9cbb97756261a0049a7fdd6a0 (patch) | |
| tree | 819926797df844de9ae09fc211daf07390ca5a04 | |
| parent | 58c3862b521ead4f69a24ef009a679cb3c519620 (diff) | |
Revert "x86/mm: Limit mmap() of /dev/mem to valid physical addresses"
This reverts commit ce56a86e2ade45d052b3228cdfebe913a1ae7381.
There's unanticipated interaction with some boot parameters like 'mem=',
which now cause the new checks via valid_mmap_phys_addr_range() to be too
restrictive, crashing a Qemu bootup in fact, as reported by Fengguang Wu.
So while the motivation of the change is still entirely valid, we
need a few more rounds of testing to get it right - it's way too late
after -rc6, so revert it for now.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Craig Bergstrom <craigb@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: dsafonov@virtuozzo.com
Cc: kirill.shutemov@linux.intel.com
Cc: mhocko@suse.com
Cc: oleg@redhat.com
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
| -rw-r--r-- | arch/x86/include/asm/io.h | 4 | ||||
| -rw-r--r-- | arch/x86/mm/mmap.c | 12 |
2 files changed, 0 insertions, 16 deletions
diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h index 322d25ae23ab..c40a95c33bb8 100644 --- a/arch/x86/include/asm/io.h +++ b/arch/x86/include/asm/io.h @@ -110,10 +110,6 @@ build_mmio_write(__writeq, "q", unsigned long, "r", ) #endif -#define ARCH_HAS_VALID_PHYS_ADDR_RANGE -extern int valid_phys_addr_range(phys_addr_t addr, size_t size); -extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size); - /** * virt_to_phys - map virtual addresses to physical * @address: address to remap diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c index 320c6237e1d1..a99679826846 100644 --- a/arch/x86/mm/mmap.c +++ b/arch/x86/mm/mmap.c @@ -174,15 +174,3 @@ const char *arch_vma_name(struct vm_area_struct *vma) return "[mpx]"; return NULL; } - -int valid_phys_addr_range(phys_addr_t addr, size_t count) -{ - return addr + count <= __pa(high_memory); -} - -int valid_mmap_phys_addr_range(unsigned long pfn, size_t count) -{ - phys_addr_t addr = (phys_addr_t)pfn << PAGE_SHIFT; - - return valid_phys_addr_range(addr, count); -} |