diff options
| author | Mika Penttilä <mika.penttila@nextfour.com> | 2016-01-26 15:47:25 +0000 |
|---|---|---|
| committer | Sasha Levin <sasha.levin@oracle.com> | 2016-02-15 15:45:23 -0500 |
| commit | daab58866c29c4e9af4d3df2175f2dc485057e46 (patch) | |
| tree | 8b4eaf83a2e034400b3973fc5da7b3c482f71927 /arch | |
| parent | 2c68386075ac61d3bedbc34491a0ed828ff832b9 (diff) | |
arm64: mm: avoid calling apply_to_page_range on empty range
[ Upstream commit 57adec866c0440976c96a4b8f5b59fb411b1cacb ]
Calling apply_to_page_range with an empty range results in a BUG_ON
from the core code. This can be triggered by trying to load the st_drv
module with CONFIG_DEBUG_SET_MODULE_RONX enabled:
kernel BUG at mm/memory.c:1874!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
Modules linked in:
CPU: 3 PID: 1764 Comm: insmod Not tainted 4.5.0-rc1+ #2
Hardware name: ARM Juno development board (r0) (DT)
task: ffffffc9763b8000 ti: ffffffc975af8000 task.ti: ffffffc975af8000
PC is at apply_to_page_range+0x2cc/0x2d0
LR is at change_memory_common+0x80/0x108
This patch fixes the issue by making change_memory_common (called by the
set_memory_* functions) a NOP when numpages == 0, therefore avoiding the
erroneous call to apply_to_page_range and bringing us into line with x86
and s390.
Cc: <stable@vger.kernel.org>
Reviewed-by: Laura Abbott <labbott@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Mika Penttilä <mika.penttila@nextfour.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm64/mm/pageattr.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c index e47ed1c5dce1..545710f854f8 100644 --- a/arch/arm64/mm/pageattr.c +++ b/arch/arm64/mm/pageattr.c @@ -57,6 +57,9 @@ static int change_memory_common(unsigned long addr, int numpages, if (end < MODULES_VADDR || end >= MODULES_END) return -EINVAL; + if (!numpages) + return 0; + data.set_mask = set_mask; data.clear_mask = clear_mask; |