Currently, the code responsible for initializing and poisoning memory in
post_alloc_hook() is scattered across two locations: kasan_alloc_pages()
hook for HW_TAGS KASAN and post_alloc_hook() itself. This is confusing.
This and a few following patches combine the code from these two
locations. Along the way, these patches do a step-by-step restructure the
many performed checks to make them easier to follow.
Replace the only caller of kasan_alloc_pages() with its implementation.
As kasan_has_integrated_init() is only true when CONFIG_KASAN_HW_TAGS is
enabled, moving the code does no functional changes.
Also move init and init_tags variables definitions out of
kasan_has_integrated_init() clause in post_alloc_hook(), as they have the
same values regardless of what the if condition evaluates to.
This patch is not useful by itself but makes the simplifications in the
following patches easier to follow.
Link: https://lkml.kernel.org/r/5ac7e0b30f5cbb177ec363ddd7878a3141289592.1643047180.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "kasan, vmalloc, arm64: add vmalloc tagging support for SW/HW_TAGS", v6.
This patchset adds vmalloc tagging support for SW_TAGS and HW_TAGS
KASAN modes.
About half of patches are cleanups I went for along the way. None of them
seem to be important enough to go through stable, so I decided not to
split them out into separate patches/series.
The patchset is partially based on an early version of the HW_TAGS
patchset by Vincenzo that had vmalloc support. Thus, I added a
Co-developed-by tag into a few patches.
SW_TAGS vmalloc tagging support is straightforward. It reuses all of the
generic KASAN machinery, but uses shadow memory to store tags instead of
magic values. Naturally, vmalloc tagging requires adding a few
kasan_reset_tag() annotations to the vmalloc code.
HW_TAGS vmalloc tagging support stands out. HW_TAGS KASAN is based on Arm
MTE, which can only assigns tags to physical memory. As a result, HW_TAGS
KASAN only tags vmalloc() allocations, which are backed by page_alloc
memory. It ignores vmap() and others.
This patch (of 39):
Currently, should_skip_kasan_poison() has two definitions: one for when
CONFIG_DEFERRED_STRUCT_PAGE_INIT is enabled, one for when it's not.
Instead of duplicating the checks, add a deferred_pages_enabled() helper
and use it in a single should_skip_kasan_poison() definition.
Also move should_skip_kasan_poison() closer to its caller and clarify all
conditions in the comment.
Link: https://lkml.kernel.org/r/cover.1643047180.git.andreyknvl@google.com
Link: https://lkml.kernel.org/r/658b79f5fb305edaf7dc16bc52ea870d3220d4a8.1643047180.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
NR_FILE_MAPPED accounting in mm/rmap.c (for /proc/meminfo "Mapped" and
/proc/vmstat "nr_mapped" and the memcg's memory.stat "mapped_file") is
slightly flawed for file or shmem huge pages.
It is well thought out, and looks convincing, but there's a racy case when
the careful counting in page_remove_file_rmap() (without page lock) gets
discarded. So that in a workload like two "make -j20" kernel builds under
memory pressure, with cc1 on hugepage text, "Mapped" can easily grow by a
spurious 5MB or more on each iteration, ending up implausibly bigger than
most other numbers in /proc/meminfo. And, hypothetically, might grow to
the point of seriously interfering in mm/vmscan.c's heuristics, which do
take NR_FILE_MAPPED into some consideration.
Fixed by moving the __mod_lruvec_page_state() down to where it will not be
missed before return (and I've grown a bit tired of that oft-repeated
but-not-everywhere comment on the __ness: it gets lost in the move here).
Does page_add_file_rmap() need the same change? I suspect not, because
page lock is held in all relevant cases, and its skipping case looks safe;
but it's much easier to be sure, if we do make the same change.
Link: https://lkml.kernel.org/r/e02e52a1-8550-a57c-ed29-f51191ea2375@google.com
Fixes: dd78fedde4 ("rmap: support file thp")
Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The PG_waiters bit is not included in PAGE_FLAGS_CHECK_AT_FREE, and
vmscan.c's free_unref_page_list() callers rely on that not to generate
bad_page() alerts. So __page_cache_release(), put_pages_list() and
release_pages() (and presumably copy-and-pasted free_zone_device_page())
are redundant and misleading to make a special point of clearing it (as
the "__" implies, it could only safely be used on the freeing path).
Delete __ClearPageWaiters(). Remark on this in one of the "possible"
comments in folio_wake_bit(), and delete the superfluous comments.
Link: https://lkml.kernel.org/r/3eafa969-5b1a-accf-88fe-318784c791a@google.com
Signed-off-by: Hugh Dickins <hughd@google.com>
Tested-by: Yu Zhao <yuzhao@google.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When viewing page owner information, we may want to cull blocks of
information with our own rules. So it is important to enhance culling
function to provide the support for customizing culling rules.
Therefore, following adjustments are made:
1. Add --cull option to support the culling of blocks of information
with user-defined culling rules.
./page_owner_sort <input> <output> --cull=<rules>
./page_owner_sort <input> <output> --cull <rules>
<rules> is a single argument in the form of a comma-separated list to
specify individual culling rules, by the sequence of keys k1,k2, ....
Mixed use of abbreviated and complete-form of keys is allowed.
For reference, please see the document(Documentation/vm/page_owner.rst).
Now, assuming two blocks in the input file are as follows:
Page allocated via order 0, mask xxxx, pid 1, tgid 1 (task_name_demo)
PFN xxxx
prep_new_page+0xd0/0xf8
get_page_from_freelist+0x4a0/0x1290
__alloc_pages+0x168/0x340
alloc_pages+0xb0/0x158
Page allocated via order 0, mask xxxx, pid 32, tgid 32 (task_name_demo)
PFN xxxx
prep_new_page+0xd0/0xf8
get_page_from_freelist+0x4a0/0x1290
__alloc_pages+0x168/0x340
alloc_pages+0xb0/0x158
If we want to cull the blocks by stacktrace and task command name, we can
use this command:
./page_owner_sort <input> <output> --cull=stacktrace,name
The output would be like:
2 times, 2 pages, task_comm_name: task_name_demo
prep_new_page+0xd0/0xf8
get_page_from_freelist+0x4a0/0x1290
__alloc_pages+0x168/0x340
alloc_pages+0xb0/0x158
As we can see, these two blocks are culled successfully, for they share
the same pid and task command name.
However, if we want to cull the blocks by pid, stacktrace and task command
name, we can this command:
./page_owner_sort <input> <output> --cull=stacktrace,name,pid
The output would be like:
1 times, 1 pages, PID 1, task_comm_name: task_name_demo
prep_new_page+0xd0/0xf8
get_page_from_freelist+0x4a0/0x1290
__alloc_pages+0x168/0x340
alloc_pages+0xb0/0x158
1 times, 1 pages, PID 32, task_comm_name: task_name_demo
prep_new_page+0xd0/0xf8
get_page_from_freelist+0x4a0/0x1290
__alloc_pages+0x168/0x340
alloc_pages+0xb0/0x158
As we can see, these two blocks are failed to cull, for their PIDs are
different.
2. Add explanations of --cull options to the document.
This work is coauthored by
Yixuan Cao
Shenghong Han
Yinan Zhang
Chongxi Zhao
Yuhong Feng
Link: https://lkml.kernel.org/r/20220312145834.624-1-yejiajian2018@email.szu.edu.cn
Signed-off-by: Jiajian Ye <yejiajian2018@email.szu.edu.cn>
Cc: Yixuan Cao <caoyixuan2019@email.szu.edu.cn>
Cc: Shenghong Han <hanshenghong2019@email.szu.edu.cn>
Cc: Yinan Zhang <zhangyinan2019@email.szu.edu.cn>
Cc: Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn>
Cc: Yuhong Feng <yuhongf@szu.edu.cn>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Sean Anderson <seanga2@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When viewing page owner information, we may also need to select the blocks
by PID, TGID or task command name, which helps to get more accurate page
allocation information as needed.
Therefore, following adjustments are made:
1. Add three new options, including --pid, --tgid and --name, to support
the selection of information blocks by a specific pid, tgid and task
command name. In addtion, multiple options are allowed to be used at
the same time.
./page_owner_sort [input] [output] --pid <PID>
./page_owner_sort [input] [output] --tgid <TGID>
./page_owner_sort [input] [output] --name <TASK_COMMAND_NAME>
Assuming a scenario when a multi-threaded program, ./demo (PID =
5280), is running, and ./demo creates a child process (PID = 5281).
$ps
PID TTY TIME CMD
5215 pts/0 00:00:00 bash
5280 pts/0 00:00:00 ./demo
5281 pts/0 00:00:00 ./demo
5282 pts/0 00:00:00 ps
It would be better to filter out the records with tgid=5280 and the
task name "demo" when debugging the parent process, and the specific
usage is
./page_owner_sort [input] [output] --tgid 5280 --name demo
2. Add explanations of three new options, including --pid, --tgid and
--name, to the document.
This work is coauthored by
Shenghong Han <hanshenghong2019@email.szu.edu.cn>,
Yixuan Cao <caoyixuan2019@email.szu.edu.cn>,
Yinan Zhang <zhangyinan2019@email.szu.edu.cn>,
Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn>,
Yuhong Feng <yuhongf@szu.edu.cn>.
Link: https://lkml.kernel.org/r/1646835223-7584-1-git-send-email-yejiajian2018@email.szu.edu.cn
Signed-off-by: Jiajian Ye <yejiajian2018@email.szu.edu.cn>
Cc: Sean Anderson <seanga2@gmail.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Zhenliang Wei <weizhenliang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In a single-threaded process, the pid in kernel task_struct is the same
as the tgid, which can mark the process of page allocation. But in a
multithreaded process, only the task_struct of the thread leader has the
same pid as tgid, and the pids of other threads are different from tgid.
Therefore, tgid is recorded to provide effective information for
debugging and data statistics of multithreaded programs.
This can also be achieved by observing the task name (executable file
name) for a specific process. However, when the same program is started
multiple times, the task name is the same and the tgid is different.
Therefore, in the debugging of multi-threaded programs, combined with
the task name and tgid, more accurate runtime information of a certain
run of the program can be obtained.
Link: https://lkml.kernel.org/r/20220219180450.2399-1-caoyixuan2019@email.szu.edu.cn
Signed-off-by: Yixuan Cao <caoyixuan2019@email.szu.edu.cn>
Cc: Waiman Long <longman@redhat.com>
Cc: Rafael Aquini <aquini@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "mm/page_owner: Extend page_owner to show memcg information", v4.
While debugging the constant increase in percpu memory consumption on a
system that spawned large number of containers, it was found that a lot
of offline mem_cgroup structures remained in place without being freed.
Further investigation indicated that those mem_cgroup structures were
pinned by some pages.
In order to find out what those pages are, the existing page_owner
debugging tool is extended to show memory cgroup information and whether
those memcgs are offline or not. With the enhanced page_owner tool, the
following is a typical page that pinned the mem_cgroup structure in my
test case:
Page allocated via order 0, mask 0x1100cca(GFP_HIGHUSER_MOVABLE), pid 162970 (podman), ts 1097761405537 ns, free_ts 1097760838089 ns
PFN 1925700 type Movable Block 3761 type Movable Flags 0x17ffffc00c001c(uptodate|dirty|lru|reclaim|swapbacked|node=0|zone=2|lastcpupid=0x1fffff)
prep_new_page+0xac/0xe0
get_page_from_freelist+0x1327/0x14d0
__alloc_pages+0x191/0x340
alloc_pages_vma+0x84/0x250
shmem_alloc_page+0x3f/0x90
shmem_alloc_and_acct_page+0x76/0x1c0
shmem_getpage_gfp+0x281/0x940
shmem_write_begin+0x36/0xe0
generic_perform_write+0xed/0x1d0
__generic_file_write_iter+0xdc/0x1b0
generic_file_write_iter+0x5d/0xb0
new_sync_write+0x11f/0x1b0
vfs_write+0x1ba/0x2a0
ksys_write+0x59/0xd0
do_syscall_64+0x37/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xae
Charged to offline memcg libpod-conmon-15e4f9c758422306b73b2dd99f9d50a5ea53cbb16b4a13a2c2308a4253cc0ec8.
So the page was not freed because it was part of a shmem segment. That
is useful information that can help users to diagnose similar problems.
With cgroup v1, /proc/cgroups can be read to find out the total number
of memory cgroups (online + offline). With cgroup v2, the cgroup.stat
of the root cgroup can be read to find the number of dying cgroups (most
likely pinned by dying memcgs).
The page_owner feature is not supposed to be enabled for production
system due to its memory overhead. However, if it is suspected that
dying memcgs are increasing over time, a test environment with
page_owner enabled can then be set up with appropriate workload for
further analysis on what may be causing the increasing number of dying
memcgs.
This patch (of 4):
For *scnprintf(), vsnprintf() is always called even if the input size is
0. That is a waste of time, so just return 0 in this case.
Note that vsnprintf() will never return -1 to indicate an error. So
skipping the call to vsnprintf() when size is 0 will have no functional
impact at all.
Link: https://lkml.kernel.org/r/20220202203036.744010-1-longman@redhat.com
Link: https://lkml.kernel.org/r/20220202203036.744010-2-longman@redhat.com
Signed-off-by: Waiman Long <longman@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Acked-by: Roman Gushchin <guro@fb.com>
Acked-by: Rafael Aquini <aquini@redhat.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When viewing the page owner information, we expect that the information
can be sorted by PID, so that we can quickly combine PID with the program
to check the information together.
We also expect that the information can be sorted by time. Time sorting
helps to view the running status of the program according to the time
interval when the program hangs up.
Finally, we hope to pass the page_ owner_ Sort. C can reduce part of the
output and only output the plate information whose memory has not been
released, which can make us locate the problem of the program faster.
Therefore, the following adjustments have been made:
1. Add the static functions search_pattern and check_regcomp to
improve the cleanliness.
2. Add member attributes and their corresponding sorting methods. In
terms of comparison time, int will overflow because the data of ull is
too large, so the ternary operator is used
3. Add the -f parameter to filter out the information of blocks whose
memory has not been released
Link: https://lkml.kernel.org/r/20211206165653.5093-1-zhaochongxi2019@email.szu.edu.cn
Signed-off-by: Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn>
Reviewed-by: Sean Anderson <seanga2@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Culling by comparing stacktrace would casue loss of some information. For
example, if there exists 2 blocks which have the same stacktrace and the
different head info
Page allocated via order 0, mask 0x108c48(...), pid 73696,
ts 1578829190639010 ns, free_ts 1576583851324450 ns
prep_new_page+0x80/0xb8
get_page_from_freelist+0x924/0xee8
__alloc_pages+0x138/0xc18
alloc_pages+0x80/0xf0
__page_cache_alloc+0x90/0xc8
Page allocated via order 0, mask 0x108c48(...), pid 61806,
ts 1354113726046100 ns, free_ts 1354104926841400 ns
prep_new_page+0x80/0xb8
get_page_from_freelist+0x924/0xee8
__alloc_pages+0x138/0xc18
alloc_pages+0x80/0xf0
__page_cache_alloc+0x90/0xc8
After culling, it would be like this
2 times, 2 pages:
Page allocated via order 0, mask 0x108c48(...), pid 73696,
ts 1578829190639010 ns, free_ts 1576583851324450 ns
prep_new_page+0x80/0xb8
get_page_from_freelist+0x924/0xee8
__alloc_pages+0x138/0xc18
alloc_pages+0x80/0xf0
__page_cache_alloc+0x90/0xc8
The info of second block missed. So, add -c to turn on culling by
stacktrace. By default, it will cull by txt.
Link: https://lkml.kernel.org/r/20211129145658.2491-1-zhangyinan2019@email.szu.edu.cn
Signed-off-by: Yinan Zhang <zhangyinan2019@email.szu.edu.cn>
Cc: Changhee Han <ch0.han@lge.com>
Cc: Sean Anderson <seanga2@gmail.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Tang Bin <tangbin@cmss.chinamobile.com>
Cc: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Cc: Zhenliang Wei <weizhenliang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
virtio spec requires drivers to set DRIVER_OK before using VQs.
This is set automatically after probe returns, but virtio-vsock
driver uses VQs in the probe function to fill rx and event VQs
with new buffers.
Let's fix this, calling virtio_device_ready() before using VQs
in the probe function.
Fixes: 0ea9e1d3a9 ("VSOCK: Introduce virtio_transport.ko")
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Complete the driver configuration, reading the negotiated features,
before using the VQs in the virtio_vsock_probe().
Fixes: 53efbba12c ("virtio/vsock: enable SEQPACKET for transport")
Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When we fill VQs with empty buffers and kick the host, it may send
an interrupt. `vdev->priv` must be initialized before this since it
is used in the virtqueue callbacks.
Fixes: 0deab087b1 ("vsock/virtio: use RCU to avoid use-after-free on the_virtio_vsock")
Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Pull ceph updates from Ilya Dryomov:
"The highlights are:
- several changes to how snap context and snap realms are tracked
(Xiubo Li). In particular, this should resolve a long-standing
issue of high kworker CPU usage and various stalls caused by
needless iteration over all inodes in the snap realm.
- async create fixes to address hangs in some edge cases (Jeff
Layton)
- support for getvxattr MDS op for querying server-side xattrs, such
as file/directory layouts and ephemeral pins (Milind Changire)
- average latency is now maintained for all metrics (Venky Shankar)
- some tweaks around handling inline data to make it fit better with
netfs helper library (David Howells)
Also a couple of memory leaks got plugged along with a few assorted
fixups. Last but not least, Xiubo has stepped up to serve as a CephFS
co-maintainer"
* tag 'ceph-for-5.18-rc1' of https://github.com/ceph/ceph-client: (27 commits)
ceph: fix memory leak in ceph_readdir when note_last_dentry returns error
ceph: uninitialized variable in debug output
ceph: use tracked average r/w/m latencies to display metrics in debugfs
ceph: include average/stdev r/w/m latency in mds metrics
ceph: track average r/w/m latency
ceph: use ktime_to_timespec64() rather than jiffies_to_timespec64()
ceph: assign the ci only when the inode isn't NULL
ceph: fix inode reference leakage in ceph_get_snapdir()
ceph: misc fix for code style and logs
ceph: allocate capsnap memory outside of ceph_queue_cap_snap()
ceph: do not release the global snaprealm until unmounting
ceph: remove incorrect and unused CEPH_INO_DOTDOT macro
MAINTAINERS: add Xiubo Li as cephfs co-maintainer
ceph: eliminate the recursion when rebuilding the snap context
ceph: do not update snapshot context when there is no new snapshot
ceph: zero the dir_entries memory when allocating it
ceph: move to a dedicated slabcache for ceph_cap_snap
ceph: add getvxattr op
libceph: drop else branches in prepare_read_data{,_cont}
ceph: fix comments mentioning i_mutex
...