linux.git/mm/vmalloc.c, branch v5.15-rc2

Merge branch 'akpm' (patches from Andrew)

2021-09-08T19:55:35+00:00

Merge more updates from Andrew Morton:
 "147 patches, based on 7d2a07b769330c34b4deabeed939325c77a7ec2f.

  Subsystems affected by this patch series: mm (memory-hotplug, rmap,
  ioremap, highmem, cleanups, secretmem, kfence, damon, and vmscan),
  alpha, percpu, procfs, misc, core-kernel, MAINTAINERS, lib,
  checkpatch, epoll, init, nilfs2, coredump, fork, pids, criu, kconfig,
  selftests, ipc, and scripts"

* emailed patches from Andrew Morton : (94 commits)
  scripts: check_extable: fix typo in user error message
  mm/workingset: correct kernel-doc notations
  ipc: replace costly bailout check in sysvipc_find_ipc()
  selftests/memfd: remove unused variable
  Kconfig.debug: drop selecting non-existing HARDLOCKUP_DETECTOR_ARCH
  configs: remove the obsolete CONFIG_INPUT_POLLDEV
  prctl: allow to setup brk for et_dyn executables
  pid: cleanup the stale comment mentioning pidmap_init().
  kernel/fork.c: unexport get_{mm,task}_exe_file
  coredump: fix memleak in dump_vma_snapshot()
  fs/coredump.c: log if a core dump is aborted due to changed file permissions
  nilfs2: use refcount_dec_and_lock() to fix potential UAF
  nilfs2: fix memory leak in nilfs_sysfs_delete_snapshot_group
  nilfs2: fix memory leak in nilfs_sysfs_create_snapshot_group
  nilfs2: fix memory leak in nilfs_sysfs_delete_##name##_group
  nilfs2: fix memory leak in nilfs_sysfs_create_##name##_group
  nilfs2: fix NULL pointer in nilfs_##name##_attr_release
  nilfs2: fix memory leak in nilfs_sysfs_create_device_group
  trap: cleanup trap_init()
  init: move usermodehelper_enable() to populate_rootfs()
  ...

mm: don't allow executable ioremap mappings

2021-09-08T18:50:24+00:00

There is no need to execute from iomem (and most platforms it is
impossible anyway), so add the pgprot_nx() call similar to vmap.

Link: https://lkml.kernel.org/r/20210824091259.1324527-3-hch@lst.de
Signed-off-by: Christoph Hellwig 
Cc: Nicholas Piggin 
Cc: Peter Zijlstra 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: move ioremap_page_range to vmalloc.c

2021-09-08T18:50:24+00:00

Patch series "small ioremap cleanups".

The first patch moves a little code around the vmalloc/ioremap boundary
following a bigger move by Nick earlier.  The second enforces
non-executable mapping on ioremap just like we do for vmap.  No driver
currently uses executable mappings anyway, as they should.

This patch (of 2):

This keeps it together with the implementation, and to remove the
vmap_range wrapper.

Link: https://lkml.kernel.org/r/20210824091259.1324527-1-hch@lst.de
Link: https://lkml.kernel.org/r/20210824091259.1324527-2-hch@lst.de
Signed-off-by: Christoph Hellwig 
Reviewed-by: Nicholas Piggin 
Cc: Peter Zijlstra 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/vmalloc: fix wrong behavior in vread

2021-09-03T16:58:14+00:00

commit f608788cd2d6 ("mm/vmalloc: use rb_tree instead of list for vread()
lookups") use rb_tree instread of list to speed up lookup, but function
__find_vmap_area is try to find a vmap_area that include target address,
if target address is smaller than the leftmost node in vmap_area_root, it
will return NULL, then vread will read nothing.  This behavior is
different from the primitive semantics.

The correct way is find the first vmap_are that bigger than target addr,
that is what function find_vmap_area_exceed_addr does.

Link: https://lkml.kernel.org/r/20210714015959.3204871-1-chenwandun@huawei.com
Fixes: f608788cd2d6 ("mm/vmalloc: use rb_tree instead of list for vread() lookups")
Signed-off-by: Chen Wandun 
Reported-by: Hulk Robot 
Cc: Serapheim Dimitropoulos 
Cc: Uladzislau Rezki (Sony) 
Cc: Kefeng Wang 
Cc: Wei Yongjun 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/vmalloc: remove gfpflags_allow_blocking() check

2021-09-03T16:58:14+00:00

Get rid of gfpflags_allow_blocking() check from the vmalloc() path as it
is supposed to be sleepable anyway.  Thus remove it from the
alloc_vmap_area() as well as from the vm_area_alloc_pages().

Link: https://lkml.kernel.org/r/20210707182639.31282-2-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) 
Acked-by: Michal Hocko 
Cc: Mel Gorman 
Cc: Christoph Hellwig 
Cc: Matthew Wilcox 
Cc: Nicholas Piggin 
Cc: Hillf Danton 
Cc: Oleksiy Avramchenko 
Cc: Steven Rostedt 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/vmalloc: use batched page requests in bulk-allocator

2021-09-03T16:58:14+00:00

In case of simultaneous vmalloc allocations, for example it is 1GB and 12
CPUs my system is able to hit "BUG: soft lockup" for !CONFIG_PREEMPT
kernel.

  RIP: 0010:__alloc_pages_bulk+0xa9f/0xbb0
  Call Trace:
   __vmalloc_node_range+0x11c/0x2d0
   __vmalloc_node+0x4b/0x70
   fix_size_alloc_test+0x44/0x60 [test_vmalloc]
   test_func+0xe7/0x1f0 [test_vmalloc]
   kthread+0x11a/0x140
   ret_from_fork+0x22/0x30

To address this issue invoke a bulk-allocator many times until all pages
are obtained, i.e.  do batched page requests adding cond_resched()
meanwhile to reschedule.  Batched value is hard-coded and is 100 pages per
call.

Link: https://lkml.kernel.org/r/20210707182639.31282-1-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) 
Acked-by: Michal Hocko 
Cc: Christoph Hellwig 
Cc: Hillf Danton 
Cc: Matthew Wilcox 
Cc: Mel Gorman 
Cc: Nicholas Piggin 
Cc: Oleksiy Avramchenko 
Cc: Steven Rostedt 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/vmalloc: include header for prototype of set_iounmap_nonlazy

2021-07-01T18:06:02+00:00

make W=1 generates the following warning for mm/vmalloc.c

  mm/vmalloc.c:1599:6: warning: no previous prototype for `set_iounmap_nonlazy' [-Wmissing-prototypes]
   void set_iounmap_nonlazy(void)
        ^~~~~~~~~~~~~~~~~~~

This is an arch-generic function only used by x86.  On other arches, it's
dead code.  Include the header with the definition and make it x86-64
specific.

Link: https://lkml.kernel.org/r/20210520084809.8576-3-mgorman@techsingularity.net
Signed-off-by: Mel Gorman 
Reviewed-by: Yang Shi 
Acked-by: Vlastimil Babka 
Cc: Dan Streetman 
Cc: David Hildenbrand 
Cc: Michal Hocko 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/vmalloc: enable mapping of huge pages at pte level in vmalloc

2021-07-01T03:47:26+00:00

On some architectures like powerpc, there are huge pages that are mapped
at pte level.

Enable it in vmalloc.

For that, architectures can provide arch_vmap_pte_supported_shift() that
returns the shift for pages to map at pte level.

Link: https://lkml.kernel.org/r/2c717e3b1fba1894d890feb7669f83025bfa314d.1620795204.git.christophe.leroy@csgroup.eu
Signed-off-by: Christophe Leroy 
Cc: Benjamin Herrenschmidt 
Cc: Michael Ellerman 
Cc: Mike Kravetz 
Cc: Mike Rapoport 
Cc: Nicholas Piggin 
Cc: Paul Mackerras 
Cc: Uladzislau Rezki 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/vmalloc: enable mapping of huge pages at pte level in vmap

2021-07-01T03:47:26+00:00

On some architectures like powerpc, there are huge pages that are mapped
at pte level.

Enable it in vmap.

For that, architectures can provide arch_vmap_pte_range_map_size() that
returns the size of pages to map at pte level.

Link: https://lkml.kernel.org/r/fb3ccc73377832ac6708181ec419128a2f98ce36.1620795204.git.christophe.leroy@csgroup.eu
Signed-off-by: Christophe Leroy 
Cc: Benjamin Herrenschmidt 
Cc: Michael Ellerman 
Cc: Mike Kravetz 
Cc: Mike Rapoport 
Cc: Nicholas Piggin 
Cc: Paul Mackerras 
Cc: Uladzislau Rezki 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: vmalloc: add cond_resched() in __vunmap()

2021-06-29T17:53:52+00:00

On non-preemptible kernel builds the watchdog can complain about soft
lockups when vfree() is called against large vmalloc areas:

[  210.851798] kvmalloc-test: vmalloc(2199023255552) succeeded
[  238.654842] watchdog: BUG: soft lockup - CPU#181 stuck for 26s! [rmmod:5203]
[  238.662716] Modules linked in: kvmalloc_test(OE-) ...
[  238.772671] CPU: 181 PID: 5203 Comm: rmmod Tainted: G S         OE     5.13.0-rc7+ #1
[  238.781413] Hardware name: Intel Corporation PURLEY/PURLEY, BIOS PLYXCRB1.86B.0553.D01.1809190614 09/19/2018
[  238.792383] RIP: 0010:free_unref_page+0x52/0x60
[  238.797447] Code: 48 c1 fd 06 48 89 ee e8 9c d0 ff ff 84 c0 74 19 9c 41 5c fa 48 89 ee 48 89 df e8 b9 ea ff ff 41 f7 c4 00 02 00 00 74 01 fb 5b <5d> 41 5c c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 f0 29 77
[  238.818406] RSP: 0018:ffffb4d87868fe98 EFLAGS: 00000206
[  238.824236] RAX: 0000000000000000 RBX: 000000001da0c945 RCX: ffffb4d87868fe40
[  238.832200] RDX: ffffd79d3beed108 RSI: ffffd7998501dc08 RDI: ffff9c6fbffd7010
[  238.840166] RBP: 000000000d518cbd R08: ffffd7998501dc08 R09: 0000000000000001
[  238.848131] R10: 0000000000000000 R11: ffffd79d3beee088 R12: 0000000000000202
[  238.856095] R13: ffff9e5be3eceec0 R14: 0000000000000000 R15: 0000000000000000
[  238.864059] FS:  00007fe082c2d740(0000) GS:ffff9f4c69b40000(0000) knlGS:0000000000000000
[  238.873089] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  238.879503] CR2: 000055a000611128 CR3: 000000f6094f6006 CR4: 00000000007706e0
[  238.887467] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  238.895433] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  238.903397] PKRU: 55555554
[  238.906417] Call Trace:
[  238.909149]  __vunmap+0x17c/0x220
[  238.912851]  __x64_sys_delete_module+0x13a/0x250
[  238.918008]  ? syscall_trace_enter.isra.20+0x13c/0x1b0
[  238.923746]  do_syscall_64+0x39/0x80
[  238.927740]  entry_SYSCALL_64_after_hwframe+0x44/0xae

Like in other range zapping routines that iterate over a large list, lets
just add cond_resched() within __vunmap()'s page-releasing loop in order
to avoid the watchdog splats.

Link: https://lkml.kernel.org/r/20210622225030.478384-1-aquini@redhat.com
Signed-off-by: Rafael Aquini 
Acked-by: Nicholas Piggin 
Reviewed-by: Uladzislau Rezki (Sony) 
Reviewed-by: Aaron Tomlin 
Acked-by: Michal Hocko 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds