linux/tools/testing/selftests/proc, branch v4.19

proc: test /proc/thread-self symlink

2018-08-22T17:52:45Z

Same story: I have WIP patch to make it faster, so better have a test as well. Link: http://lkml.kernel.org/r/20180627195209.GC18113@avx2 Signed-off-by: Alexey Dobriyan Cc: Shuah Khan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

proc: test /proc/self symlink

2018-08-22T17:52:45Z

There are plans to change how /proc/self result is calculated, for that a test is necessary. Use direct system call because of this whole getpid caching story. Link: http://lkml.kernel.org/r/20180627195103.GB18113@avx2 Signed-off-by: Alexey Dobriyan Cc: Shuah Khan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

tools/testing/selftests/proc: test /proc/*/fd a bit (+ PF_KTHREAD is ABI!)

2018-06-08T00:34:38Z

* Test lookup in /proc/self/fd. "map_files" lookup story showed that lookup is not that simple. * Test that all those symlinks open the same file. Check with (st_dev, st_info). * Test that kernel threads do not have anything in their /proc/*/fd/ directory. Now this is where things get interesting. First, kernel threads aren't pinned by /proc/self or equivalent, thus some "atomicity" is required. Second, ->comm can contain whitespace and ')'. No, they are not escaped. Third, the only reliable way to check if process is kernel thread appears to be field #9 in /proc/*/stat. This field is struct task_struct::flags in decimal! Check is done by testing PF_KTHREAD flags like we do in kernel. PF_KTREAD value is a part of userspace ABI !!! Other methods for determining kernel threadness are not reliable: * RSS can be 0 if everything is swapped, even while reading from /proc/self. * ->total_vm CAN BE ZERO if process is finishing munmap(NULL, whole address space); * /proc/*/maps and similar files can be empty because unmapping everything works. Read returning 0 can't distinguish between kernel thread and such suicide process. Link: http://lkml.kernel.org/r/20180505000414.GA15090@avx2 Signed-off-by: Alexey Dobriyan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

proc: fixup copyright sign

2018-04-13T03:52:25Z

Add copyright in two files before they get autorubberstamped. Signed-off-by: Alexey Dobriyan Signed-off-by: Linus Torvalds

proc: selftests: test /proc/uptime

2018-04-11T17:28:34Z

The only tests I could come up with for /proc/uptime are: - test that values increase monotonically for 1 second, - bounce around CPUs and test the same thing. Avoid glibc like plague for affinity given patches like this: https://marc.info/?l=linux-kernel&m=152130031912594&w=4 Link: http://lkml.kernel.org/r/20180317165235.GB3445@avx2 Signed-off-by: Alexey Dobriyan Cc: Shuah Khan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

proc: selftests: shotgun testing of read/readdir/readlink/write

2018-04-11T17:28:34Z

Perform reads with nearly everything in /proc, and some writing as well. Hopefully memleak checkers and KASAN will find something. [adobriyan@gmail.com: /proc/kmsg can and will block if read under root] Link: http://lkml.kernel.org/r/20180316232147.GA20146@avx2 Signed-off-by: Alexey Dobriyan [adobriyan@gmail.com: /proc/sysrq-trigger lives on the ground floor] Link: http://lkml.kernel.org/r/20180317164911.GA3445@avx2 Link: http://lkml.kernel.org/r/20180315201251.GA12396@avx2 Signed-off-by: Alexey Dobriyan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

proc: add selftest for last field of /proc/loadavg

2018-04-11T17:28:34Z

Test fork counter formerly known as ->last_pid, the only part of /proc/loadavg which can be tested. Testing in init pid namespace is not reliable because of background activity. Link: http://lkml.kernel.org/r/20180311152241.GA26247@avx2 Signed-off-by: Alexey Dobriyan Cc: Shuah Khan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

proc: fix /proc/*/map_files lookup some more

2018-04-11T17:28:34Z

I totally forgot that _parse_integer() accepts arbitrary amount of leading zeroes leading to the following lookups: OK # readlink /proc/1/map_files/56427ecba000-56427eddc000 /lib/systemd/systemd bogus # readlink /proc/1/map_files/00000000000056427ecba000-56427eddc000 /lib/systemd/systemd # readlink /proc/1/map_files/56427ecba000-00000000000056427eddc000 /lib/systemd/systemd Link: http://lkml.kernel.org/r/20180303215130.GA23480@avx2 Signed-off-by: Alexey Dobriyan Reviewed-by: Cyrill Gorcunov Reviewed-by: Andrew Morton Cc: Pavel Emelyanov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

proc: test /proc/self/syscall

2018-04-11T17:28:34Z

Read from /proc/self/syscall should yield read system call and correct args in the output as current is reading /proc/self/syscall. Link: http://lkml.kernel.org/r/20180226212145.GB742@avx2 Signed-off-by: Alexey Dobriyan Cc: Shuah Khan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

proc: test /proc/self/wchan

2018-04-11T17:28:34Z

This patch starts testing /proc. Many more tests to come (I promise). Read from /proc/self/wchan should always return "0" as current is in TASK_RUNNING state while reading /proc/self/wchan. Link: http://lkml.kernel.org/r/20180226212006.GA742@avx2 Signed-off-by: Alexey Dobriyan Cc: Shuah Khan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds