linux/tools/testing/selftests/proc, branch v6.4

selftests/proc: Assert clock_gettime(CLOCK_BOOTTIME) VS /proc/uptime monotonicity

2023-04-18T14:35:13Z

The first field of /proc/uptime relies on the CLOCK_BOOTTIME clock which can also be fetched from clock_gettime() API. Improve the test coverage while verifying the monotonicity of CLOCK_BOOTTIME accross both interfaces. Suggested-by: Thomas Gleixner Signed-off-by: Frederic Weisbecker Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20230222144649.624380-9-frederic@kernel.org

selftests/proc: Remove idle time monotonicity assertions

2023-04-18T14:35:13Z

Due to broken iowait task counting design (cf: comments above get_cpu_idle_time_us() and nr_iowait()), it is not possible to provide the guarantee that /proc/stat or /proc/uptime display monotonic idle time values. Remove the assertions that verify the related wrong assumption so that testers and maintainers don't spend more time on that. Reported-by: Yu Liao Reported-by: Thomas Gleixner Signed-off-by: Frederic Weisbecker Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20230222144649.624380-8-frederic@kernel.org

proc: fix PIE proc-empty-vm, proc-pid-vm tests

2023-01-12T00:14:22Z

vsyscall detection code uses direct call to the beginning of the vsyscall page: asm ("call %P0" :: "i" (0xffffffffff600000)) It generates "call rel32" instruction but it is not relocated if binary is PIE, so binary segfaults into random userspace address and vsyscall page status is detected incorrectly. Do more direct: asm ("call *%rax") which doesn't do need any relocaltions. Mark g_vsyscall as volatile for a good measure, I didn't find instruction setting it to 0. Now the code is obviously correct: xor eax, eax mov rdi, rbp mov rsi, rbp mov DWORD PTR [rip+0x2d15], eax # g_vsyscall = 0 mov rax, 0xffffffffff600000 call rax mov DWORD PTR [rip+0x2d02], 1 # g_vsyscall = 1 mov eax, DWORD PTR ds:0xffffffffff600000 mov DWORD PTR [rip+0x2cf1], 2 # g_vsyscall = 2 mov edi, [rip+0x2ceb] # exit(g_vsyscall) call exit Note: fixed proc-empty-vm test oopses 5.19.0-28-generic kernel but this is separate story. Link: https://lkml.kernel.org/r/Y7h2xvzKLg36DSq8@p183 Fixes: 5bc73bb3451b9 ("proc: test how it holds up with mapping'less process") Signed-off-by: Alexey Dobriyan Reported-by: Mirsad Goran Todorovac Tested-by: Mirsad Goran Todorovac Cc: Signed-off-by: Andrew Morton

proc: fixup uptime selftest

2022-11-18T21:55:08Z

syscall(3) returns -1 and sets errno on error, unlike "syscall" instruction. Systems which have <= 32/64 CPUs are unaffected. Test won't bounce to all CPUs before completing if there are more of them. Link: https://lkml.kernel.org/r/Y1bUiT7VRXlXPQa1@p183 Fixes: 1f5bd0547654 ("proc: selftests: test /proc/uptime") Signed-off-by: Alexey Dobriyan Signed-off-by: Andrew Morton

proc: test how it holds up with mapping'less process

2022-10-12T01:51:11Z

Create process without mappings and check /proc/*/maps /proc/*/numa_maps /proc/*/smaps /proc/*/smaps_rollup They must be empty (excluding vsyscall page) or full of zeroes. Retroactively this test should've caught embarassing /proc/*/smaps_rollup oops: [17752.703567] BUG: kernel NULL pointer dereference, address: 0000000000000000 [17752.703580] #PF: supervisor read access in kernel mode [17752.703583] #PF: error_code(0x0000) - not-present page [17752.703587] PGD 0 P4D 0 [17752.703593] Oops: 0000 [#1] PREEMPT SMP PTI [17752.703598] CPU: 0 PID: 60649 Comm: cat Tainted: G W 5.19.9-100.fc35.x86_64 #1 [17752.703603] Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./X99 Extreme6/3.1, BIOS P3.30 08/05/2016 [17752.703607] RIP: 0010:show_smaps_rollup+0x159/0x2e0 Note 1: ProtectionKey field in /proc/*/smaps is optional, so check most of its contents, not everything. Note 2: due to the nature of this test, child process hardly can signal its readiness (after unmapping everything!) to parent. I feel like "sleep(1)" is justified. If you know how to do it without sleep please tell me. Note 3: /proc/*/statm is not tested but can be. Link: https://lkml.kernel.org/r/Yz3liL6Dn+n2SD8Q@localhost.localdomain Signed-off-by: Alexey Dobriyan Signed-off-by: Andrew Morton

proc: save LOC in vsyscall test

2022-09-12T04:55:06Z

Do one fork in vsyscall detection code and let SIGSEGV handler exit and carry information to the parent saving LOC. [adobriyan@gmail.com: redo original patch, delete unnecessary variables, minimise code changes] Link: https://lkml.kernel.org/r/YvoWzAn5dlhF75xa@localhost.localdomain Signed-off-by: Alexey Dobriyan Signed-off-by: Brian Foster Reviewed-by: Brian Foster Tested-by: Brian Foster Signed-off-by: Andrew Morton

proc: fix test for "vsyscall=xonly" boot option

2022-07-18T00:31:43Z

Booting with vsyscall=xonly results in the following vsyscall VMA: ffffffffff600000-ffffffffff601000 --xp ... [vsyscall] Test does read from fixed vsyscall address to determine if kernel supports vsyscall page but it doesn't work because, well, vsyscall page is execute only. Fix test by trying to execute from the first byte of the page which contains gettimeofday() stub. This should work because vsyscall entry points have stable addresses by design. Alexey, avoiding parsing .config, /proc/config.gz and /proc/cmdline at all costs. Link: https://lkml.kernel.org/r/Ys2KgeiEMboU8Ytu@localhost.localdomain Signed-off-by: Alexey Dobriyan Cc: Shuah Khan Cc: Signed-off-by: Andrew Morton

selftests/proc: fix array_size.cocci warning

2022-04-04T19:27:21Z

Fix the following coccicheck warning: tools/testing/selftests/proc/proc-pid-vm.c:371:26-27: WARNING: Use ARRAY_SIZE tools/testing/selftests/proc/proc-pid-vm.c:420:26-27: WARNING: Use ARRAY_SIZE It has been tested with gcc (Debian 8.3.0-6) 8.3.0 on x86_64. Signed-off-by: Guo Zhengkui Signed-off-by: Shuah Khan

procfs: do not list TID 0 in /proc//task

2021-11-09T18:02:48Z

If a task exits concurrently, task_pid_nr_ns may return 0. [akpm@linux-foundation.org: coding style tweaks] [adobriyan@gmail.com: test that /proc/*/task doesn't contain "0"] Link: https://lkml.kernel.org/r/YV88AnVzHxPafQ9o@localhost.localdomain Link: https://lkml.kernel.org/r/8735pn5dx7.fsf@oldenburg.str.redhat.com Signed-off-by: Florian Weimer Signed-off-by: Alexey Dobriyan Acked-by: Christian Brauner Reviewed-by: Alexey Dobriyan Cc: Kees Cook Cc: "Eric W. Biederman" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

proc: add .gitignore for proc-subset-pid selftest

2021-06-05T15:58:11Z

This new selftest needs an entry in the .gitignore file otherwise git will try to track the binary. Link: https://lkml.kernel.org/r/20210601164305.11776-1-dmatlack@google.com Fixes: 268af17ada5855 ("selftests: proc: test subset=pid") Signed-off-by: David Matlack Acked-by: Christian Brauner Cc: Shuah Khan Cc: Alexey Dobriyan Cc: Alexey Gladkov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds