@@ -97,7 +97,8 @@ radix__arch_get_unmapped_area(struct file *filp, unsigned long addr,
struct vm_area_struct *vma;
struct vm_unmapped_area_info info;
- if (unlikely(addr > mm->context.addr_limit && addr < TASK_SIZE))
+ if (unlikely(addr > mm->context.addr_limit &&
+ mm->context.addr_limit != TASK_SIZE))
mm->context.addr_limit = TASK_SIZE;
if (len > mm->context.addr_limit - mmap_min_addr)
@@ -139,7 +140,8 @@ radix__arch_get_unmapped_area_topdown(struct file *filp,
unsigned long addr = addr0;
struct vm_unmapped_area_info info;
- if (unlikely(addr > mm->context.addr_limit && addr < TASK_SIZE))
+ if (unlikely(addr > mm->context.addr_limit &&
+ mm->context.addr_limit != TASK_SIZE))
mm->context.addr_limit = TASK_SIZE;
/* requested length too big for entire address space */
@@ -419,7 +419,8 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
/*
* Check if we need to expland slice area.
*/
- if (unlikely(addr > mm->context.addr_limit && addr < TASK_SIZE)) {
+ if (unlikely(addr > mm->context.addr_limit &&
+ mm->context.addr_limit != TASK_SIZE)) {
mm->context.addr_limit = TASK_SIZE;
on_each_cpu(slice_flush_segments, mm, 1);
}
We added the addr < TASK_SIZE check to avoid updating addr_limit unnecessarily and also to avoid calling slice_flush_segments on all the cpus. This had the side effect of having different behaviour when using an addr value above TASK_SIZE before updating addr_limit and after updating addr_limit as show by below output: requesting with hint 0x0 Addr returned 0x7fff893a0000 requesting with hint 0xffffffffffffffff Addr returned 0x7fff891b0000 <===== 1st return requesting with hint 0x1000000000000 Addr returned 0x1000000000000 requesting with hint 0xffffffffffffffff Addr returned 0x1ffff89410000 <==== second return After fix: requesting with hint 0x0 Addr returned 0x7fff8bc00000 requesting with hint 0xffffffffffffffff Addr returned 0x1ffff8bc80000 <==== 1st return requesting with hint 0x1000000000000 Addr returned 0x1000000000000 requesting with hint 0xffffffffffffffff Addr returned 0x1ffff8bc60000 <==== second return Fixes: 1b49451ebd3e9 (powerpc/mm: Enable mappings above 128TB) Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> --- arch/powerpc/mm/mmap.c | 6 ++++-- arch/powerpc/mm/slice.c | 3 ++- 2 files changed, 6 insertions(+), 3 deletions(-)