diff options
author | Mel Gorman <mgorman@suse.de> | 2015-02-12 23:58:25 +0100 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-02-13 03:54:08 +0100 |
commit | 842915f56667f9eebd85932f08c79565148c26d6 (patch) | |
tree | 4d8f962c206f28965c8d94da40d6237b94ce8f66 /arch/powerpc/mm/copro_fault.c | |
parent | mm: convert p[te|md]_numa users to p[te|md]_protnone_numa (diff) | |
download | linux-842915f56667f9eebd85932f08c79565148c26d6.tar.xz linux-842915f56667f9eebd85932f08c79565148c26d6.zip |
ppc64: add paranoid warnings for unexpected DSISR_PROTFAULT
ppc64 should not be depending on DSISR_PROTFAULT and it's unexpected if
they are triggered. This patch adds warnings just in case they are being
accidentally depended upon.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Jones <davej@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/powerpc/mm/copro_fault.c')
-rw-r--r-- | arch/powerpc/mm/copro_fault.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/arch/powerpc/mm/copro_fault.c b/arch/powerpc/mm/copro_fault.c index 1b5305d4bdab..f031a47d7701 100644 --- a/arch/powerpc/mm/copro_fault.c +++ b/arch/powerpc/mm/copro_fault.c @@ -64,10 +64,14 @@ int copro_handle_mm_fault(struct mm_struct *mm, unsigned long ea, if (!(vma->vm_flags & VM_WRITE)) goto out_unlock; } else { - if (dsisr & DSISR_PROTFAULT) - goto out_unlock; if (!(vma->vm_flags & (VM_READ | VM_EXEC))) goto out_unlock; + /* + * protfault should only happen due to us + * mapping a region readonly temporarily. PROT_NONE + * is also covered by the VMA check above. + */ + WARN_ON_ONCE(dsisr & DSISR_PROTFAULT); } ret = 0; |