On 11/20/2017 10:33 AM, Michal Hocko wrote:
On Mon 20-11-17 10:10:32, Florian Weimer wrote:
On 11/20/2017 09:55 AM, Michal Hocko wrote:
On Fri 17-11-17 08:30:48, Florian Weimer wrote:
On 11/16/2017 11:18 AM, Michal Hocko wrote:
+ if (flags & MAP_FIXED_SAFE) {
+ struct vm_area_struct *vma = find_vma(mm, addr);
+
+ if (vma && vma->vm_start <= addr)
+ return -ENOMEM;
+ }
Could you pick a different error code which cannot also be caused by a an
unrelated, possibly temporary condition? Maybe EBUSY or EEXIST?
Hmm, none of those are described in the man page. I am usually very
careful to not add new and potentially unexpected error codes but it is
I think this is a bad idea. It leads to bizarre behavior, like open failing
with EOVERFLOW with certain namespace configurations (which have nothing to
do with file sizes).
Ohh, I agree but breaking userspace is, you know, no-no. And an
unexpected error codes can break things terribly.
On the glibc side, we see a lot of changes in error codes depending on
kernel version, build and run-time configuration. It never occurred to
me that you guys think the precise error code is part of the userspace
ABI. Personally, I even assume that failure itself can disappear at any
time (evidence: the f* functions which accept O_PATH in their non-*at
variants).
Thanks,
Florian