Re: [PATCH] proc: fix proc-self-map-files selftest for arm
From: Rafael David Tinoco
Date: Mon Oct 15 2018 - 12:55:27 EST
On 10/11/18 7:00 PM, Cyrill Gorcunov wrote:
On Fri, Oct 12, 2018 at 12:30:06AM +0300, Alexey Dobriyan wrote:
On Fri, Oct 12, 2018 at 12:02:56AM +0300, Cyrill Gorcunov wrote:
On Thu, Oct 11, 2018 at 11:56:01PM +0300, Alexey Dobriyan wrote:
As the comment in the beginning says this test is specifically for addresss 0.
Maybe it should be ifdeffed with __arm__ then.
Is there some other reason than allocating non-mergable VMA?
IIRC the reason is to test address 0 as it is effectively banned
for userspace so if it will be broken, it will be broken silently
for a long time.
This is rather a side effect of the test because the primary reason
was to check procfs numbers conversion, right? Don't get me wrong,
I don't mind about __arm__ define or similar, this is fine for
one architecture, but if there comes more we will get a number
of #ifdefs which is unrelated to procfs numeric routines at all.
That is what I also had in mind, thus the patch. I just realized we had
another issue on LKFT (our functional tests tool) for
proc-self-map-files-001.c. Test 001 does pretty much the same as 002,
but without the MAP_FIXED mmap flag.
Is it okay to consolidate both tests into just 1, and focus in checking
procfs numbers conversion only, rather than if mapping 0 is allowed or
not ? Can I send a v2 with that in mind ?
As for "unmergeable" libc here doesn't map /dev/zero. I know how to
avoid even theoretical breakage by creating binaries by hand but it
will be probably too much.
Sure.