kernel/linux.git/tools/testing/selftests/proc/proc-empty-vm.c, branch v6.6.131

selftests/proc: fixup proc-empty-vm test after KSM changes

2023-09-19T20:21:33+00:00

/proc/${pid}/smaps_rollup is not empty file even if process's address space is empty, update the test. Link: https://lkml.kernel.org/r/725e041f-e9df-4f3d-b267-d4cd2774a78d@p183 Signed-off-by: Alexey Dobriyan Cc: David Hildenbrand Cc: Stefan Roesch Signed-off-by: Andrew Morton

Merge tag 'mm-nonmm-stable-2023-08-28-22-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2023-08-29T21:53:51+00:00

Pull non-MM updates from Andrew Morton: - An extensive rework of kexec and crash Kconfig from Eric DeVolder ("refactor Kconfig to consolidate KEXEC and CRASH options") - kernel.h slimming work from Andy Shevchenko ("kernel.h: Split out a couple of macros to args.h") - gdb feature work from Kuan-Ying Lee ("Add GDB memory helper commands") - vsprintf inclusion rationalization from Andy Shevchenko ("lib/vsprintf: Rework header inclusions") - Switch the handling of kdump from a udev scheme to in-kernel handling, by Eric DeVolder ("crash: Kernel handling of CPU and memory hot un/plug") - Many singleton patches to various parts of the tree * tag 'mm-nonmm-stable-2023-08-28-22-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (81 commits) document while_each_thread(), change first_tid() to use for_each_thread() drivers/char/mem.c: shrink character device's devlist[] array x86/crash: optimize CPU changes crash: change crash_prepare_elf64_headers() to for_each_possible_cpu() crash: hotplug support for kexec_load() x86/crash: add x86 crash hotplug support crash: memory and CPU hotplug sysfs attributes kexec: exclude elfcorehdr from the segment digest crash: add generic infrastructure for crash hotplug support crash: move a few code bits to setup support of crash hotplug kstrtox: consistently use _tolower() kill do_each_thread() nilfs2: fix WARNING in mark_buffer_dirty due to discarded buffer reuse scripts/bloat-o-meter: count weak symbol sizes treewide: drop CONFIG_EMBEDDED lockdep: fix static memory detection even more lib/vsprintf: declare no_hash_pointers in sprintf.h lib/vsprintf: split out sprintf() and friends kernel/fork: stop playing lockless games for exe_file replacement adfs: delete unused "union adfs_dirtail" definition ...

mm,thp: fix smaps THPeligible output alignment

2023-08-21T20:38:01+00:00

Extract from current /proc/self/smaps output: Swap: 0 kB SwapPss: 0 kB Locked: 0 kB THPeligible: 0 ProtectionKey: 0 That's not the alignment shown in Documentation/filesystems/proc.rst: it's an ugly artifact from missing out the %8 other fields are using; but there's even one selftest which expects it to look that way. Hoping no other smaps parsers depend on THPeligible to look so ugly, fix these. Link: https://lkml.kernel.org/r/cfb81f7a-f448-5bc2-b0e1-8136fcd1dd8c@google.com Signed-off-by: Hugh Dickins Cc: Alexey Dobriyan Signed-off-by: Andrew Morton

proc: skip proc-empty-vm on anything but amd64 and i386

2023-08-18T17:18:50+00:00

This test is arch specific, requires "munmap everything" primitive. Link: https://lkml.kernel.org/r/20230630183434.17434-2-adobriyan@gmail.com Signed-off-by: Alexey Dobriyan Cc: Björn Töpel Signed-off-by: Andrew Morton

proc: support proc-empty-vm test on i386

2023-08-18T17:18:49+00:00

Unmap everything starting from 4GB length until it unmaps, otherwise test has to detect which virtual memory split kernel is using. Link: https://lkml.kernel.org/r/20230630183434.17434-1-adobriyan@gmail.com Signed-off-by: Alexey Dobriyan Cc: Björn Töpel Signed-off-by: Andrew Morton

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

2023-01-12T00:14:22+00:00

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: test how it holds up with mapping'less process

2022-10-12T01:51:11+00:00

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