10 Commits

Author SHA1 Message Date
Swarup Laxman Kotiaklapudi
bf5add391e proc: test ProtectionKey in proc-empty-vm test
Check ProtectionKey field in /proc/*/smaps output, if system supports
protection keys feature.

[adobriyan@gmail.com: test support in the beginning of the program, use syscall, not glibc pkey_alloc(3) which may not compile]

Link: https://lkml.kernel.org/r/ac05efa7-d2a0-48ad-b704-ffdd5450582e@p183
Signed-off-by: Swarup Laxman Kotiaklapudi <swarupkotikalapudi@gmail.com>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Swarup Laxman Kotikalapudi<swarupkotikalapudi@gmail.com>
Tested-by: Swarup Laxman Kotikalapudi<swarupkotikalapudi@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-11-01 12:46:59 -07:00
Alexey Dobriyan
20e34aa7e0 proc: fix proc-empty-vm test with vsyscall
* fix embarassing /proc/*/smaps test bug due to a typo in variable name
  it tested only the first line of the output if vsyscall is enabled:

  	ffffffffff600000-ffffffffff601000 r-xp ...

  so test passed but tested only VMA location and permissions.

* add "KSM" entry, unnoticed because (1)

* swap "r-xp" and "--xp" vsyscall test strings,
  also unnoticed because (1)

Link: https://lkml.kernel.org/r/76f42cce-b1ab-45ec-b6b2-4c64f0dccb90@p183
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Tested-by: Swarup Laxman Kotikalapudi<swarupkotikalapudi@mail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-11-01 12:46:59 -07:00
Swarup Laxman Kotiaklapudi
6e79b375ad proc: test /proc/${pid}/statm
My original comment lied, output can be "0 A A B 0 0 0\n"
(see comment in the code).

I don't quite understand why

	get_mm_counter(mm, MM_FILEPAGES) + get_mm_counter(mm, MM_SHMEMPAGES)

can stay positive but get_mm_counter(mm, MM_ANONPAGES) is always 0 after
everything is unmapped but that's just me.

[adobriyan@gmail.com: more or less rewritten]
Link: https://lkml.kernel.org/r/0721ca69-7bb4-40aa-8d01-0c5f91e5f363@p183
Signed-off-by: Swarup Laxman Kotiaklapudi <swarupkotikalapudi@gmail.com>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-18 14:43:22 -07:00
Alexey Dobriyan
9d1be94df5 selftests/proc: fixup proc-empty-vm test after KSM changes
/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 <adobriyan@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Stefan Roesch <shr@devkernel.io>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-09-19 13:21:33 -07:00
Linus Torvalds
d68b4b6f30 - 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
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Merge tag 'mm-nonmm-stable-2023-08-28-22-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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
  ...
2023-08-29 14:53:51 -07:00
Hugh Dickins
daa60ae64c mm,thp: fix smaps THPeligible output alignment
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 <hughd@google.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-21 13:38:01 -07:00
Alexey Dobriyan
f58a2dd8d5 proc: skip proc-empty-vm on anything but amd64 and i386
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 <adobriyan@gmail.com>
Cc: Björn Töpel <bjorn@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18 10:18:50 -07:00
Alexey Dobriyan
4356b11ec0 proc: support proc-empty-vm test on i386
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 <adobriyan@gmail.com>
Cc: Björn Töpel <bjorn@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18 10:18:49 -07:00
Alexey Dobriyan
5316a017d0 proc: fix PIE proc-empty-vm, proc-pid-vm tests
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 <adobriyan@gmail.com>
Reported-by: Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr>
Tested-by: Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-11 16:14:22 -08:00
Alexey Dobriyan
5bc73bb345 proc: test how it holds up with mapping'less process
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 <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-11 18:51:11 -07:00