Pull memblock fix from Mike Rapoport:
"Use kfree() to release kmalloced memblock regions
memblock.{reserved,memory}.regions may be allocated using kmalloc()
in memblock_double_array(). Use kfree() to release these kmalloced
regions"
* tag 'fixes-2022-02-26' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock:
memblock: use kfree() to release kmalloced memblock regions
When we specify a large number for node in hugepages parameter, it may
be parsed to another number due to truncation in this statement:
node = tmp;
For example, add following parameter in command line:
hugepagesz=1G hugepages=4294967297:5
and kernel will allocate 5 hugepages for node 1 instead of ignoring it.
I move the validation check earlier to fix this issue, and slightly
simplifies the condition here.
Link: https://lkml.kernel.org/r/20220209134018.8242-1-liuyuntao10@huawei.com
Fixes: b5389086ad ("hugetlbfs: extend the definition of hugepages parameter to support node allocation")
Signed-off-by: Liu Yuntao <liuyuntao10@huawei.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This fixes the below crash:
kernel BUG at include/linux/mm.h:2373!
cpu 0x5d: Vector: 700 (Program Check) at [c00000003c6e76e0]
pc: c000000000581a54: pmd_to_page+0x54/0x80
lr: c00000000058d184: move_hugetlb_page_tables+0x4e4/0x5b0
sp: c00000003c6e7980
msr: 9000000000029033
current = 0xc00000003bd8d980
paca = 0xc000200fff610100 irqmask: 0x03 irq_happened: 0x01
pid = 9349, comm = hugepage-mremap
kernel BUG at include/linux/mm.h:2373!
move_hugetlb_page_tables+0x4e4/0x5b0 (link register)
move_hugetlb_page_tables+0x22c/0x5b0 (unreliable)
move_page_tables+0xdbc/0x1010
move_vma+0x254/0x5f0
sys_mremap+0x7c0/0x900
system_call_exception+0x160/0x2c0
the kernel can't use huge_pte_offset before it set the pte entry because
a page table lookup check for huge PTE bit in the page table to
differentiate between a huge pte entry and a pointer to pte page. A
huge_pte_alloc won't mark the page table entry huge and hence kernel
should not use huge_pte_offset after a huge_pte_alloc.
Link: https://lkml.kernel.org/r/20220211063221.99293-1-aneesh.kumar@linux.ibm.com
Fixes: 550a7d60bd ("mm, hugepages: add mremap() support for hugepage backed vma")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
memblock.{reserved,memory}.regions may be allocated using kmalloc() in
memblock_double_array(). Use kfree() to release these kmalloced regions
indicated by memblock_{reserved,memory}_in_slab.
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Fixes: 3010f87650 ("mm: discard memblock data later")
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Oded Gabbay reports that enabling NUMA balancing causes corruption with
his Gaudi accelerator test load:
"All the details are in the bug, but the bottom line is that somehow,
this patch causes corruption when the numa balancing feature is
enabled AND we don't use process affinity AND we use GUP to pin pages
so our accelerator can DMA to/from system memory.
Either disabling numa balancing, using process affinity to bind to
specific numa-node or reverting this patch causes the bug to
disappear"
and Oded bisected the issue to commit 09854ba94c ("mm: do_wp_page()
simplification").
Now, the NUMA balancing shouldn't actually be changing the writability
of a page, and as such shouldn't matter for COW. But it appears it
does. Suspicious.
However, regardless of that, the condition for enabling NUMA faults in
change_pte_range() is nonsensical. It uses "page_mapcount(page)" to
decide if a COW page should be NUMA-protected or not, and that makes
absolutely no sense.
The number of mappings a page has is irrelevant: not only does GUP get a
reference to a page as in Oded's case, but the other mappings migth be
paged out and the only reference to them would be in the page count.
Since we should never try to NUMA-balance a page that we can't move
anyway due to other references, just fix the code to use 'page_count()'.
Oded confirms that that fixes his issue.
Now, this does imply that something in NUMA balancing ends up changing
page protections (other than the obvious one of making the page
inaccessible to get the NUMA faulting information). Otherwise the COW
simplification wouldn't matter - since doing the GUP on the page would
make sure it's writable.
The cause of that permission change would be good to figure out too,
since it clearly results in spurious COW events - but fixing the
nonsensical test that just happened to work before is obviously the
CorrectThing(tm) to do regardless.
Fixes: 09854ba94c ("mm: do_wp_page() simplification")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215616
Link: https://lore.kernel.org/all/CAFCwf10eNmwq2wD71xjUhqkvv5+_pJMR1nPug2RqNDcFT4H86Q@mail.gmail.com/
Reported-and-tested-by: Oded Gabbay <oded.gabbay@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alexander reported a circular lock dependency revealed by the mmap1 ltp
test:
LOCKDEP_CIRCULAR (suite: ltp, case: mtest06 (mmap1))
WARNING: possible circular locking dependency detected
5.17.0-20220113.rc0.git0.f2211f194038.300.fc35.s390x+debug #1 Not tainted
------------------------------------------------------
mmap1/202299 is trying to acquire lock:
00000001892c0188 (css_set_lock){..-.}-{2:2}, at: obj_cgroup_release+0x4a/0xe0
but task is already holding lock:
00000000ca3b3818 (&sighand->siglock){-.-.}-{2:2}, at: force_sig_info_to_task+0x38/0x180
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&sighand->siglock){-.-.}-{2:2}:
__lock_acquire+0x604/0xbd8
lock_acquire.part.0+0xe2/0x238
lock_acquire+0xb0/0x200
_raw_spin_lock_irqsave+0x6a/0xd8
__lock_task_sighand+0x90/0x190
cgroup_freeze_task+0x2e/0x90
cgroup_migrate_execute+0x11c/0x608
cgroup_update_dfl_csses+0x246/0x270
cgroup_subtree_control_write+0x238/0x518
kernfs_fop_write_iter+0x13e/0x1e0
new_sync_write+0x100/0x190
vfs_write+0x22c/0x2d8
ksys_write+0x6c/0xf8
__do_syscall+0x1da/0x208
system_call+0x82/0xb0
-> #0 (css_set_lock){..-.}-{2:2}:
check_prev_add+0xe0/0xed8
validate_chain+0x736/0xb20
__lock_acquire+0x604/0xbd8
lock_acquire.part.0+0xe2/0x238
lock_acquire+0xb0/0x200
_raw_spin_lock_irqsave+0x6a/0xd8
obj_cgroup_release+0x4a/0xe0
percpu_ref_put_many.constprop.0+0x150/0x168
drain_obj_stock+0x94/0xe8
refill_obj_stock+0x94/0x278
obj_cgroup_charge+0x164/0x1d8
kmem_cache_alloc+0xac/0x528
__sigqueue_alloc+0x150/0x308
__send_signal+0x260/0x550
send_signal+0x7e/0x348
force_sig_info_to_task+0x104/0x180
force_sig_fault+0x48/0x58
__do_pgm_check+0x120/0x1f0
pgm_check_handler+0x11e/0x180
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&sighand->siglock);
lock(css_set_lock);
lock(&sighand->siglock);
lock(css_set_lock);
*** DEADLOCK ***
2 locks held by mmap1/202299:
#0: 00000000ca3b3818 (&sighand->siglock){-.-.}-{2:2}, at: force_sig_info_to_task+0x38/0x180
#1: 00000001892ad560 (rcu_read_lock){....}-{1:2}, at: percpu_ref_put_many.constprop.0+0x0/0x168
stack backtrace:
CPU: 15 PID: 202299 Comm: mmap1 Not tainted 5.17.0-20220113.rc0.git0.f2211f194038.300.fc35.s390x+debug #1
Hardware name: IBM 3906 M04 704 (LPAR)
Call Trace:
dump_stack_lvl+0x76/0x98
check_noncircular+0x136/0x158
check_prev_add+0xe0/0xed8
validate_chain+0x736/0xb20
__lock_acquire+0x604/0xbd8
lock_acquire.part.0+0xe2/0x238
lock_acquire+0xb0/0x200
_raw_spin_lock_irqsave+0x6a/0xd8
obj_cgroup_release+0x4a/0xe0
percpu_ref_put_many.constprop.0+0x150/0x168
drain_obj_stock+0x94/0xe8
refill_obj_stock+0x94/0x278
obj_cgroup_charge+0x164/0x1d8
kmem_cache_alloc+0xac/0x528
__sigqueue_alloc+0x150/0x308
__send_signal+0x260/0x550
send_signal+0x7e/0x348
force_sig_info_to_task+0x104/0x180
force_sig_fault+0x48/0x58
__do_pgm_check+0x120/0x1f0
pgm_check_handler+0x11e/0x180
INFO: lockdep is turned off.
In this example a slab allocation from __send_signal() caused a
refilling and draining of a percpu objcg stock, resulted in a releasing
of another non-related objcg. Objcg release path requires taking the
css_set_lock, which is used to synchronize objcg lists.
This can create a circular dependency with the sighandler lock, which is
taken with the locked css_set_lock by the freezer code (to freeze a
task).
In general it seems that using css_set_lock to synchronize objcg lists
makes any slab allocations and deallocation with the locked css_set_lock
and any intervened locks risky.
To fix the problem and make the code more robust let's stop using
css_set_lock to synchronize objcg lists and use a new dedicated spinlock
instead.
Link: https://lkml.kernel.org/r/Yfm1IHmoGdyUR81T@carbon.dhcp.thefacebook.com
Fixes: bf4f059954 ("mm: memcg/slab: obj_cgroup API")
Signed-off-by: Roman Gushchin <guro@fb.com>
Reported-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Tested-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Reviewed-by: Waiman Long <longman@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Jeremy Linton <jeremy.linton@arm.com>
Tested-by: Jeremy Linton <jeremy.linton@arm.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A soft lockup bug in kcompactd was reported in a private bugzilla with
the following visible in dmesg;
watchdog: BUG: soft lockup - CPU#33 stuck for 26s! [kcompactd0:479]
watchdog: BUG: soft lockup - CPU#33 stuck for 52s! [kcompactd0:479]
watchdog: BUG: soft lockup - CPU#33 stuck for 78s! [kcompactd0:479]
watchdog: BUG: soft lockup - CPU#33 stuck for 104s! [kcompactd0:479]
The machine had 256G of RAM with no swap and an earlier failed
allocation indicated that node 0 where kcompactd was run was potentially
unreclaimable;
Node 0 active_anon:29355112kB inactive_anon:2913528kB active_file:0kB
inactive_file:0kB unevictable:64kB isolated(anon):0kB isolated(file):0kB
mapped:8kB dirty:0kB writeback:0kB shmem:26780kB shmem_thp:
0kB shmem_pmdmapped: 0kB anon_thp: 23480320kB writeback_tmp:0kB
kernel_stack:2272kB pagetables:24500kB all_unreclaimable? yes
Vlastimil Babka investigated a crash dump and found that a task
migrating pages was trying to drain PCP lists;
PID: 52922 TASK: ffff969f820e5000 CPU: 19 COMMAND: "kworker/u128:3"
Call Trace:
__schedule
schedule
schedule_timeout
wait_for_completion
__flush_work
__drain_all_pages
__alloc_pages_slowpath.constprop.114
__alloc_pages
alloc_migration_target
migrate_pages
migrate_to_node
do_migrate_pages
cpuset_migrate_mm_workfn
process_one_work
worker_thread
kthread
ret_from_fork
This failure is specific to CONFIG_PREEMPT=n builds. The root of the
problem is that kcompact0 is not rescheduling on a CPU while a task that
has isolated a large number of the pages from the LRU is waiting on
kcompact0 to reschedule so the pages can be released. While
shrink_inactive_list() only loops once around too_many_isolated, reclaim
can continue without rescheduling if sc->skipped_deactivate == 1 which
could happen if there was no file LRU and the inactive anon list was not
low.
Link: https://lkml.kernel.org/r/20220203100326.GD3301@suse.de
Fixes: d818fca1ca ("mm/vmscan: throttle reclaim and compaction when too may pages are isolated")
Signed-off-by: Mel Gorman <mgorman@suse.de>
Debugged-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When using devm_request_free_mem_region() and devm_memremap_pages() to
add ZONE_DEVICE memory, if requested free mem region's end pfn were
huge(e.g., 0x400000000), the node_end_pfn() will be also huge (see
move_pfn_range_to_zone()). Thus it creates a huge hole between
node_start_pfn() and node_end_pfn().
We found on some AMD APUs, amdkfd requested such a free mem region and
created a huge hole. In such a case, following code snippet was just
doing busy test_bit() looping on the huge hole.
for (pfn = start_pfn; pfn < end_pfn; pfn++) {
struct page *page = pfn_to_online_page(pfn);
if (!page)
continue;
...
}
So we got a soft lockup:
watchdog: BUG: soft lockup - CPU#6 stuck for 26s! [bash:1221]
CPU: 6 PID: 1221 Comm: bash Not tainted 5.15.0-custom #1
RIP: 0010:pfn_to_online_page+0x5/0xd0
Call Trace:
? kmemleak_scan+0x16a/0x440
kmemleak_write+0x306/0x3a0
? common_file_perm+0x72/0x170
full_proxy_write+0x5c/0x90
vfs_write+0xb9/0x260
ksys_write+0x67/0xe0
__x64_sys_write+0x1a/0x20
do_syscall_64+0x3b/0xc0
entry_SYSCALL_64_after_hwframe+0x44/0xae
I did some tests with the patch.
(1) amdgpu module unloaded
before the patch:
real 0m0.976s
user 0m0.000s
sys 0m0.968s
after the patch:
real 0m0.981s
user 0m0.000s
sys 0m0.973s
(2) amdgpu module loaded
before the patch:
real 0m35.365s
user 0m0.000s
sys 0m35.354s
after the patch:
real 0m1.049s
user 0m0.000s
sys 0m1.042s
Link: https://lkml.kernel.org/r/20211108140029.721144-1-lang.yu@amd.com
Signed-off-by: Lang Yu <lang.yu@amd.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
syzbot detected a case where the page table counters were not properly
updated.
syzkaller login: ------------[ cut here ]------------
kernel BUG at mm/page_table_check.c:162!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 3099 Comm: pasha Not tainted 5.16.0+ #48
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIO4
RIP: 0010:__page_table_check_zero+0x159/0x1a0
Call Trace:
free_pcp_prepare+0x3be/0xaa0
free_unref_page+0x1c/0x650
free_compound_page+0xec/0x130
free_transhuge_page+0x1be/0x260
__put_compound_page+0x90/0xd0
release_pages+0x54c/0x1060
__pagevec_release+0x7c/0x110
shmem_undo_range+0x85e/0x1250
...
The repro involved having a huge page that is split due to uprobe event
temporarily replacing one of the pages in the huge page. Later the huge
page was combined again, but the counters were off, as the PTE level was
not properly updated.
Make sure that when PMD is cleared and prior to freeing the level the
PTEs are updated.
Link: https://lkml.kernel.org/r/20220131203249.2832273-5-pasha.tatashin@soleen.com
Fixes: df4e817b71 ("mm: page table check")
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Paul Turner <pjt@google.com>
Cc: Wei Xu <weixugc@google.com>
Cc: Will Deacon <will@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit 54d516b1d6
That commit did a refactoring that effectively combined fast and slow
gup paths (again). And that was again incorrect, for two reasons:
a) Fast gup and slow gup get reference counts on pages in different
ways and with different goals: see Linus' writeup in commit
cd1adf1b63 ("Revert "mm/gup: remove try_get_page(), call
try_get_compound_head() directly""), and
b) try_grab_compound_head() also has a specific check for
"FOLL_LONGTERM && !is_pinned(page)", that assumes that the caller
can fall back to slow gup. This resulted in new failures, as
recently report by Will McVicker [1].
But (a) has problems too, even though they may not have been reported
yet. So just revert this.
Link: https://lore.kernel.org/r/20220131203504.3458775-1-willmcvicker@google.com [1]
Fixes: 54d516b1d6 ("mm/gup: small refactoring: simplify try_grab_page()")
Reported-and-tested-by: Will McVicker <willmcvicker@google.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Minchan Kim <minchan@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: stable@vger.kernel.org # 5.15
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull bitmap updates from Yury Norov:
- introduce for_each_set_bitrange()
- use find_first_*_bit() instead of find_next_*_bit() where possible
- unify for_each_bit() macros
* tag 'bitmap-5.17-rc1' of git://github.com/norov/linux:
vsprintf: rework bitmap_list_string
lib: bitmap: add performance test for bitmap_print_to_pagebuf
bitmap: unify find_bit operations
mm/percpu: micro-optimize pcpu_is_populated()
Replace for_each_*_bit_from() with for_each_*_bit() where appropriate
find: micro-optimize for_each_{set,clear}_bit()
include/linux: move for_each_bit() macros from bitops.h to find.h
cpumask: replace cpumask_next_* with cpumask_first_* where appropriate
tools: sync tools/bitmap with mother linux
all: replace find_next{,_zero}_bit with find_first{,_zero}_bit where appropriate
cpumask: use find_first_and_bit()
lib: add find_first_and_bit()
arch: remove GENERIC_FIND_FIRST_BIT entirely
include: move find.h from asm_generic to linux
bitops: move find_bit_*_le functions from le.h to find.h
bitops: protect find_first_{,zero}_bit properly
Merge yet more updates from Andrew Morton:
"This is the post-linux-next queue. Material which was based on or
dependent upon material which was in -next.
69 patches.
Subsystems affected by this patch series: mm (migration and zsmalloc),
sysctl, proc, and lib"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (69 commits)
mm: hide the FRONTSWAP Kconfig symbol
frontswap: remove support for multiple ops
mm: mark swap_lock and swap_active_head static
frontswap: simplify frontswap_register_ops
frontswap: remove frontswap_test
mm: simplify try_to_unuse
frontswap: remove the frontswap exports
frontswap: simplify frontswap_init
frontswap: remove frontswap_curr_pages
frontswap: remove frontswap_shrink
frontswap: remove frontswap_tmem_exclusive_gets
frontswap: remove frontswap_writethrough
mm: remove cleancache
lib/stackdepot: always do filter_irq_stacks() in stack_depot_save()
lib/stackdepot: allow optional init and stack_table allocation by kvmalloc()
proc: remove PDE_DATA() completely
fs: proc: store PDE()->data into inode->i_private
zsmalloc: replace get_cpu_var with local_lock
zsmalloc: replace per zpage lock with pool->migrate_lock
locking/rwlocks: introduce write_lock_nested
...
Pull more folio updates from Matthew Wilcox:
"Three small folio patches.
One bug fix, one patch pulled forward from the patches destined for
5.18 and then a patch to make use of that functionality"
* tag 'folio-5.17a' of git://git.infradead.org/users/willy/pagecache:
filemap: Use folio_put_refs() in filemap_free_folio()
mm: Add folio_put_refs()
pagevec: Initialise folio_batch->percpu_pvec_drained
Currently, enabling CONFIG_STACKDEPOT means its stack_table will be
allocated from memblock, even if stack depot ends up not actually used.
The default size of stack_table is 4MB on 32-bit, 8MB on 64-bit.
This is fine for use-cases such as KASAN which is also a config option
and has overhead on its own. But it's an issue for functionality that
has to be actually enabled on boot (page_owner) or depends on hardware
(GPU drivers) and thus the memory might be wasted. This was raised as
an issue [1] when attempting to add stackdepot support for SLUB's debug
object tracking functionality. It's common to build kernels with
CONFIG_SLUB_DEBUG and enable slub_debug on boot only when needed, or
create only specific kmem caches with debugging for testing purposes.
It would thus be more efficient if stackdepot's table was allocated only
when actually going to be used. This patch thus makes the allocation
(and whole stack_depot_init() call) optional:
- Add a CONFIG_STACKDEPOT_ALWAYS_INIT flag to keep using the current
well-defined point of allocation as part of mem_init(). Make
CONFIG_KASAN select this flag.
- Other users have to call stack_depot_init() as part of their own init
when it's determined that stack depot will actually be used. This may
depend on both config and runtime conditions. Convert current users
which are page_owner and several in the DRM subsystem. Same will be
done for SLUB later.
- Because the init might now be called after the boot-time memblock
allocation has given all memory to the buddy allocator, change
stack_depot_init() to allocate stack_table with kvmalloc() when
memblock is no longer available. Also handle allocation failure by
disabling stackdepot (could have theoretically happened even with
memblock allocation previously), and don't unnecessarily align the
memblock allocation to its own size anymore.
[1] https://lore.kernel.org/all/CAMuHMdW=eoVzM1Re5FVoEN87nKfiLmM2+Ah7eNu2KXEhCvbZyA@mail.gmail.com/
Link: https://lkml.kernel.org/r/20211013073005.11351-1-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Marco Elver <elver@google.com> # stackdepot
Cc: Marco Elver <elver@google.com>
Cc: Vijayanand Jitta <vjitta@codeaurora.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Oliver Glitta <glittao@gmail.com>
Cc: Imran Khan <imran.f.khan@oracle.com>
From: Colin Ian King <colin.king@canonical.com>
Subject: lib/stackdepot: fix spelling mistake and grammar in pr_err message
There is a spelling mistake of the work allocation so fix this and
re-phrase the message to make it easier to read.
Link: https://lkml.kernel.org/r/20211015104159.11282-1-colin.king@canonical.com
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
From: Vlastimil Babka <vbabka@suse.cz>
Subject: lib/stackdepot: allow optional init and stack_table allocation by kvmalloc() - fixup
On FLATMEM, we call page_ext_init_flatmem_late() just before
kmem_cache_init() which means stack_depot_init() (called by page owner
init) will not recognize properly it should use kvmalloc() and not
memblock_alloc(). memblock_alloc() will also not issue a warning and
return a block memory that can be invalid and cause kernel page fault when
saving stacks, as reported by the kernel test robot [1].
Fix this by moving page_ext_init_flatmem_late() below kmem_cache_init() so
that slab_is_available() is true during stack_depot_init(). SPARSEMEM
doesn't have this issue, as it doesn't do page_ext_init_flatmem_late(),
but a different page_ext_init() even later in the boot process.
Thanks to Mike Rapoport for pointing out the FLATMEM init ordering issue.
While at it, also actually resolve a checkpatch warning in stack_depot_init()
from DRM CI, which was supposed to be in the original patch already.
[1] https://lore.kernel.org/all/20211014085450.GC18719@xsang-OptiPlex-9020/
Link: https://lkml.kernel.org/r/6abd9213-19a9-6d58-cedc-2414386d2d81@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: kernel test robot <oliver.sang@intel.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
From: Vlastimil Babka <vbabka@suse.cz>
Subject: lib/stackdepot: allow optional init and stack_table allocation by kvmalloc() - fixup3
Due to cd06ab2fd4 ("drm/locking: add backtrace for locking contended
locks without backoff") landing recently to -next adding a new stack depot
user in drivers/gpu/drm/drm_modeset_lock.c we need to add an appropriate
call to stack_depot_init() there as well.
Link: https://lkml.kernel.org/r/2a692365-cfa1-64f2-34e0-8aa5674dce5e@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Naresh Kamboju <naresh.kamboju@linaro.org>
Cc: Marco Elver <elver@google.com>
Cc: Vijayanand Jitta <vjitta@codeaurora.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Oliver Glitta <glittao@gmail.com>
Cc: Imran Khan <imran.f.khan@oracle.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
From: Vlastimil Babka <vbabka@suse.cz>
Subject: lib/stackdepot: allow optional init and stack_table allocation by kvmalloc() - fixup4
Due to 4e66934eaa ("lib: add reference counting tracking
infrastructure") landing recently to net-next adding a new stack depot
user in lib/ref_tracker.c we need to add an appropriate call to
stack_depot_init() there as well.
Link: https://lkml.kernel.org/r/45c1b738-1a2f-5b5f-2f6d-86fab206d01c@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Cc: Jiri Slab <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The zsmalloc has used a bit for spin_lock in zpage handle to keep zpage
object alive during several operations. However, it causes the problem
for PREEMPT_RT as well as introducing too complicated.
This patch replaces the bit spin_lock with pool->migrate_lock rwlock.
It could make the code simple as well as zsmalloc work under PREEMPT_RT.
The drawback is the pool->migrate_lock is bigger granuarity than per
zpage lock so the contention would be higher than old when both
IO-related operations(i.e., zsmalloc, zsfree, zs_[map|unmap]) and
compaction(page/zpage migration) are going in parallel(*, the
migrate_lock is rwlock and IO related functions are all read side lock
so there is no contention). However, the write-side is fast
enough(dominant overhead is just page copy) so it wouldn't affect much.
If the lock granurity becomes more problem later, we could introduce
table locks based on handle as a hash value.
Link: https://lkml.kernel.org/r/20211115185909.3949505-9-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "zsmalloc: remove bit_spin_lock", v2.
zsmalloc uses bit_spin_lock to minimize space overhead since it's zpage
granularity lock. However, it causes zsmalloc non-working under
PREEMPT_RT as well as adding too much complication.
This patchset tries to replace the bit_spin_lock with per-pool rwlock.
It also removes unnecessary zspage isolation logic from class, which was
the other part too much complication added into zsmalloc.
Last patch changes the get_cpu_var to local_lock to make it work in
PREEMPT_RT.
This patch (of 9):
get_zspage_mapping returns fullness as well as class_idx. However, the
fullness is usually not used since it could be stale in some contexts.
It causes misleading as well as unnecessary instructions so this patch
introduces zspage_class.
obj_to_location also produces page and index but we don't need always
the index, either so this patch introduces obj_to_page.
Link: https://lkml.kernel.org/r/20211115185909.3949505-1-minchan@kernel.org
Link: https://lkml.kernel.org/r/20211115185909.3949505-2-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This fixes the FIXME in migrate_vma_check_page().
Before migrating a page migration code will take a reference and check
there are no unexpected page references, failing the migration if there
are. When a thread faults on a migration entry it will take a temporary
reference to the page to wait for the page to become unlocked signifying
the migration entry has been removed.
This reference is dropped just prior to waiting on the page lock,
however the extra reference can cause migration failures so it is
desirable to avoid taking it.
As migration code already has a reference to the migrating page an extra
reference to wait on PG_locked is unnecessary so long as the reference
can't be dropped whilst setting up the wait.
When faulting on a migration entry the ptl is taken to check the
migration entry. Removing a migration entry also requires the ptl, and
migration code won't drop its page reference until after the migration
entry has been removed. Therefore retaining the ptl of a migration
entry is sufficient to ensure the page has a reference. Reworking
migration_entry_wait() to hold the ptl until the wait setup is complete
means the extra page reference is no longer needed.
[apopple@nvidia.com: v5]
Link: https://lkml.kernel.org/r/20211213033848.1973946-1-apopple@nvidia.com
Link: https://lkml.kernel.org/r/20211118020754.954425-1-apopple@nvidia.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge more updates from Andrew Morton:
"55 patches.
Subsystems affected by this patch series: percpu, procfs, sysctl,
misc, core-kernel, get_maintainer, lib, checkpatch, binfmt, nilfs2,
hfs, fat, adfs, panic, delayacct, kconfig, kcov, and ubsan"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (55 commits)
lib: remove redundant assignment to variable ret
ubsan: remove CONFIG_UBSAN_OBJECT_SIZE
kcov: fix generic Kconfig dependencies if ARCH_WANTS_NO_INSTR
lib/Kconfig.debug: make TEST_KMOD depend on PAGE_SIZE_LESS_THAN_256KB
btrfs: use generic Kconfig option for 256kB page size limit
arch/Kconfig: split PAGE_SIZE_LESS_THAN_256KB from PAGE_SIZE_LESS_THAN_64KB
configs: introduce debug.config for CI-like setup
delayacct: track delays from memory compact
Documentation/accounting/delay-accounting.rst: add thrashing page cache and direct compact
delayacct: cleanup flags in struct task_delay_info and functions use it
delayacct: fix incomplete disable operation when switch enable to disable
delayacct: support swapin delay accounting for swapping without blkio
panic: remove oops_id
panic: use error_report_end tracepoint on warnings
fs/adfs: remove unneeded variable make code cleaner
FAT: use io_schedule_timeout() instead of congestion_wait()
hfsplus: use struct_group_attr() for memcpy() region
nilfs2: remove redundant pointer sbufs
fs/binfmt_elf: use PT_LOAD p_align values for static PIE
const_structs.checkpatch: add frequently used ops structs
...
Delay accounting does not track the delay of memory compact. When there
is not enough free memory, tasks can spend a amount of their time
waiting for compact.
To get the impact of tasks in direct memory compact, measure the delay
when allocating memory through memory compact.
Also update tools/accounting/getdelays.c:
/ # ./getdelays_next -di -p 304
print delayacct stats ON
printing IO accounting
PID 304
CPU count real total virtual total delay total delay average
277 780000000 849039485 18877296 0.068ms
IO count delay total delay average
0 0 0ms
SWAP count delay total delay average
0 0 0ms
RECLAIM count delay total delay average
5 11088812685 2217ms
THRASHING count delay total delay average
0 0 0ms
COMPACT count delay total delay average
3 72758 0ms
watch: read=0, write=0, cancelled_write=0
Link: https://lkml.kernel.org/r/1638619795-71451-1-git-send-email-wang.yong12@zte.com.cn
Signed-off-by: wangyong <wang.yong12@zte.com.cn>
Reviewed-by: Jiang Xuexin <jiang.xuexin@zte.com.cn>
Reviewed-by: Zhang Wenya <zhang.wenya1@zte.com.cn>
Reviewed-by: Yang Yang <yang.yang29@zte.com.cn>
Reviewed-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
