fuse_simple_request() is converted to return length of last (instead of
single) out arg, since FUSE_IOCTL_OUT has two out args, the second of which
is variable length.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
fuse_req_pages_alloc() is moved to file.c, since its internal use by the
device code will eventually be removed.
Rename to fuse_pages_alloc() to signify that it's not only usable for
fuse_req page array.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Derive fuse_args_pages from fuse_args. This is used to handle requests
which use pages for input or output. The related flags are added to
fuse_args.
New FR_ALLOC_PAGES flags is added to indicate whether the page arrays in
fuse_req need to be freed by fuse_put_request() or not.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
We can use the "force" flag to make sure the DESTROY request is always sent
to userspace. So no need to keep it allocated during the lifetime of the
filesystem.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
In some cases it makes no sense to set pid/uid/gid fields in the request
header. Allow fuse_simple_background() to omit these. This is only
required in the "force" case, so for now just WARN if set otherwise.
Fold fuse_get_req_nofail_nopages() into its only caller. Comment is
obsolete anyway.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
This will be used by fuse_force_forget().
We can expand fuse_request_send() into fuse_simple_request(). The
FR_WAITING bit has already been set, no need to check.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Add 'force' to fuse_args and use fuse_get_req_nofail_nopages() to allocate
the request in that case.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Instead of complex games with a reserved request, just use __GFP_NOFAIL.
Both calers (flush, readdir) guarantee that connection was already
initialized, so no need to wait for fc->initialized.
Also remove unneeded clearing of FR_BACKGROUND flag.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
...to make future expansion simpler. The hiearachical structure is a
historical thing that does not serve any practical purpose.
The generated code is excatly the same before and after the patch.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
When IOCB_CMD_POLL is used on the FUSE device, aio_poll() disables IRQs
and takes kioctx::ctx_lock, then fuse_iqueue::waitq.lock.
This may have to wait for fuse_iqueue::waitq.lock to be released by one
of many places that take it with IRQs enabled. Since the IRQ handler
may take kioctx::ctx_lock, lockdep reports that a deadlock is possible.
Fix it by protecting the state of struct fuse_iqueue with a separate
spinlock, and only accessing fuse_iqueue::waitq using the versions of
the waitqueue functions which do IRQ-safe locking internally.
Reproducer:
#include <fcntl.h>
#include <stdio.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <unistd.h>
#include <linux/aio_abi.h>
int main()
{
char opts[128];
int fd = open("/dev/fuse", O_RDWR);
aio_context_t ctx = 0;
struct iocb cb = { .aio_lio_opcode = IOCB_CMD_POLL, .aio_fildes = fd };
struct iocb *cbp = &cb;
sprintf(opts, "fd=%d,rootmode=040000,user_id=0,group_id=0", fd);
mkdir("mnt", 0700);
mount("foo", "mnt", "fuse", 0, opts);
syscall(__NR_io_setup, 1, &ctx);
syscall(__NR_io_submit, ctx, 1, &cbp);
}
Beginning of lockdep output:
=====================================================
WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected
5.3.0-rc5 #9 Not tainted
-----------------------------------------------------
syz_fuse/135 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
000000003590ceda (&fiq->waitq){+.+.}, at: spin_lock include/linux/spinlock.h:338 [inline]
000000003590ceda (&fiq->waitq){+.+.}, at: aio_poll fs/aio.c:1751 [inline]
000000003590ceda (&fiq->waitq){+.+.}, at: __io_submit_one.constprop.0+0x203/0x5b0 fs/aio.c:1825
and this task is already holding:
0000000075037284 (&(&ctx->ctx_lock)->rlock){..-.}, at: spin_lock_irq include/linux/spinlock.h:363 [inline]
0000000075037284 (&(&ctx->ctx_lock)->rlock){..-.}, at: aio_poll fs/aio.c:1749 [inline]
0000000075037284 (&(&ctx->ctx_lock)->rlock){..-.}, at: __io_submit_one.constprop.0+0x1f4/0x5b0 fs/aio.c:1825
which would create a new lock dependency:
(&(&ctx->ctx_lock)->rlock){..-.} -> (&fiq->waitq){+.+.}
but this new dependency connects a SOFTIRQ-irq-safe lock:
(&(&ctx->ctx_lock)->rlock){..-.}
[...]
Reported-by: syzbot+af05535bb79520f95431@syzkaller.appspotmail.com
Reported-by: syzbot+d86c4426a01f60feddc7@syzkaller.appspotmail.com
Fixes: bfe4037e72 ("aio: implement IOCB_CMD_POLL")
Cc: <stable@vger.kernel.org> # v4.19+
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
The unused vfs code can be removed. Don't pass empty subtype (same as if
->parse callback isn't called).
The bits that are left involve determining whether it's permitted to split the
filesystem type string passed in to mount(2). Consequently, this means that we
cannot get rid of the FS_HAS_SUBTYPE flag unless we define that a type string
with a dot in it always indicates a subtype specification.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Convert the fuse filesystem to the new internal mount API as the old
one will be obsoleted and removed. This allows greater flexibility in
communication of mount parameters between userspace, the VFS and the
filesystem.
See Documentation/filesystems/mount_api.txt for more information.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Provide a function, get_tree_mtd(), to replace mount_mtd(), using an
fs_context struct to hold the parameters.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: David Woodhouse <dwmw2@infradead.org>
cc: Brian Norris <computersforpeace@gmail.com>
cc: Boris Brezillon <bbrezillon@kernel.org>
cc: Marek Vasut <marek.vasut@gmail.com>
cc: Richard Weinberger <richard@nod.at>
cc: linux-mtd@lists.infradead.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Create a function, get_tree_bdev(), that is fs_context-aware and a
->get_tree() counterpart of mount_bdev().
It caches the block device pointer in the fs_context struct so that this
information can be passed into sget_fc()'s test and set functions.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Jens Axboe <axboe@kernel.dk>
cc: linux-block@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The inode parameter in cuse_release() is likely *not* a fuse inode. It's a
small wonder it didn't blow up until now.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
[ This retries commit d4b13963f2 ("fuse: require /dev/fuse reads to have
enough buffer capacity"), which was reverted. In this version we require
only `sizeof(fuse_in_header) + sizeof(fuse_write_in)` instead of 4K for
FUSE request header room, because, contrary to libfuse and kernel client
behaviour, GlusterFS actually provides only so much room for request
header. ]
A FUSE filesystem server queues /dev/fuse sys_read calls to get filesystem
requests to handle. It does not know in advance what would be that request
as it can be anything that client issues - LOOKUP, READ, WRITE, ... Many
requests are short and retrieve data from the filesystem. However WRITE and
NOTIFY_REPLY write data into filesystem.
Before getting into operation phase, FUSE filesystem server and kernel
client negotiate what should be the maximum write size the client will ever
issue. After negotiation the contract in between server/client is that the
filesystem server then should queue /dev/fuse sys_read calls with enough
buffer capacity to receive any client request - WRITE in particular, while
FUSE client should not, in particular, send WRITE requests with >
negotiated max_write payload. FUSE client in kernel and libfuse
historically reserve 4K for request header. However an existing filesystem
server - GlusterFS - was found which reserves only 80 bytes for header room
(= `sizeof(fuse_in_header) + sizeof(fuse_write_in)`).
Since
`sizeof(fuse_in_header) + sizeof(fuse_write_in)` ==
`sizeof(fuse_in_header) + sizeof(fuse_read_in)` ==
`sizeof(fuse_in_header) + sizeof(fuse_notify_retrieve_in)`
is the absolute minimum any sane filesystem should be using for header
room, the contract is that filesystem server should queue sys_reads with
`sizeof(fuse_in_header) + sizeof(fuse_write_in)` + max_write buffer.
If the filesystem server does not follow this contract, what can happen
is that fuse_dev_do_read will see that request size is > buffer size,
and then it will return EIO to client who issued the request but won't
indicate in any way that there is a problem to filesystem server.
This can be hard to diagnose because for some requests, e.g. for
NOTIFY_REPLY which mimics WRITE, there is no client thread that is
waiting for request completion and that EIO goes nowhere, while on
filesystem server side things look like the kernel is not replying back
after successful NOTIFY_RETRIEVE request made by the server.
We can make the problem easy to diagnose if we indicate via error return to
filesystem server when it is violating the contract. This should not
practically cause problems because if a filesystem server is using shorter
buffer, writes to it were already very likely to cause EIO, and if the
filesystem is read-only it should be too following FUSE_MIN_READ_BUFFER
minimum buffer size.
Please see [1] for context where the problem of stuck filesystem was hit
for real (because kernel client was incorrectly sending more than
max_write data with NOTIFY_REPLY; see also previous patch), how the
situation was traced and for more involving patch that did not make it
into the tree.
[1] https://marc.info/?l=linux-fsdevel&m=155057023600853&w=2
Signed-off-by: Kirill Smelkov <kirr@nexedi.com>
Tested-by: Sander Eikelenboom <linux@eikelenboom.it>
Cc: Han-Wen Nienhuys <hanwen@google.com>
Cc: Jakob Unterwurzacher <jakobunt@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
UBIFS:
- Don't block too long in writeback_inodes_sb()
- Fix for a possible overrun of the log head
- Fix double unlock in orphan_delete()
JFFS2:
- Remove C++ style from UAPI header and unbreak picky toolchains
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Merge tag 'for-linus-5.3-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs
Pull UBIFS and JFFS2 fixes from Richard Weinberger:
"UBIFS:
- Don't block too long in writeback_inodes_sb()
- Fix for a possible overrun of the log head
- Fix double unlock in orphan_delete()
JFFS2:
- Remove C++ style from UAPI header and unbreak picky toolchains"
* tag 'for-linus-5.3-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
ubifs: Limit the number of pages in shrink_liability
ubifs: Correctly initialize c->min_log_bytes
ubifs: Fix double unlock around orphan_delete()
jffs2: Remove C++ style comments from uapi header
Pull x86 fixes from Thomas Gleixner:
"A few fixes for x86:
- Fix a boot regression caused by the recent bootparam sanitizing
change, which escaped the attention of all people who reviewed that
code.
- Address a boot problem on machines with broken E820 tables caused
by an underflow which ended up placing the trampoline start at
physical address 0.
- Handle machines which do not advertise a legacy timer of any form,
but need calibration of the local APIC timer gracefully by making
the calibration routine independent from the tick interrupt. Marked
for stable as well as there seems to be quite some new laptops
rolled out which expose this.
- Clear the RDRAND CPUID bit on AMD family 15h and 16h CPUs which are
affected by broken firmware which does not initialize RDRAND
correctly after resume. Add a command line parameter to override
this for machine which either do not use suspend/resume or have a
fixed BIOS. Unfortunately there is no way to detect this on boot,
so the only safe decision is to turn it off by default.
- Prevent RFLAGS from being clobbers in CALL_NOSPEC on 32bit which
caused fast KVM instruction emulation to break.
- Explain the Intel CPU model naming convention so that the repeating
discussions come to an end"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/retpoline: Don't clobber RFLAGS during CALL_NOSPEC on i386
x86/boot: Fix boot regression caused by bootparam sanitizing
x86/CPU/AMD: Clear RDRAND CPUID bit on AMD family 15h/16h
x86/boot/compressed/64: Fix boot on machines with broken E820 table
x86/apic: Handle missing global clockevent gracefully
x86/cpu: Explain Intel model naming convention
Pull timekeeping fix from Thomas Gleixner:
"A single fix for a regression caused by the generic VDSO
implementation where a math overflow causes CLOCK_BOOTTIME to become a
random number generator"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timekeeping/vsyscall: Prevent math overflow in BOOTTIME update
Pull scheduler fix from Thomas Gleixner:
"Handle the worker management in situations where a task is scheduled
out on a PI lock contention correctly and schedule a new worker if
possible"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/core: Schedule new worker even if PI-blocked
Pull perf fixes from Thomas Gleixner:
"Two small fixes for kprobes and perf:
- Prevent a deadlock in kprobe_optimizer() causes by reverse lock
ordering
- Fix a comment typo"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
kprobes: Fix potential deadlock in kprobe_optimizer()
perf/x86: Fix typo in comment
Pull irq fix from Thomas Gleixner:
"A single fix for a imbalanced kobject operation in the irq decriptor
code which was unearthed by the new warnings in the kobject code"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq: Properly pair kobject_del() with kobject_add()
Mergr misc fixes from Andrew Morton:
"11 fixes"
Mostly VM fixes, one psi polling fix, and one parisc build fix.
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm/kasan: fix false positive invalid-free reports with CONFIG_KASAN_SW_TAGS=y
mm/zsmalloc.c: fix race condition in zs_destroy_pool
mm/zsmalloc.c: migration can leave pages in ZS_EMPTY indefinitely
mm, page_owner: handle THP splits correctly
userfaultfd_release: always remove uffd flags and clear vm_userfaultfd_ctx
psi: get poll_work to run when calling poll syscall next time
mm: memcontrol: flush percpu vmevents before releasing memcg
mm: memcontrol: flush percpu vmstats before releasing memcg
parisc: fix compilation errrors
mm, page_alloc: move_freepages should not examine struct page of reserved memory
mm/z3fold.c: fix race between migration and destruction
Two fixes for regressions in this merge window:
- select the Kconfig symbols for the noncoherent dma arch helpers
on arm if swiotlb is selected, not just for LPAE to not break then
Xen build, that uses swiotlb indirectly through swiotlb-xen
- fix the page allocator fallback in dma_alloc_contiguous if the CMA
allocation fails
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Merge tag 'dma-mapping-5.3-5' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping fixes from Christoph Hellwig:
"Two fixes for regressions in this merge window:
- select the Kconfig symbols for the noncoherent dma arch helpers on
arm if swiotlb is selected, not just for LPAE to not break then Xen
build, that uses swiotlb indirectly through swiotlb-xen
- fix the page allocator fallback in dma_alloc_contiguous if the CMA
allocation fails"
* tag 'dma-mapping-5.3-5' of git://git.infradead.org/users/hch/dma-mapping:
dma-direct: fix zone selection after an unaddressable CMA allocation
arm: select the dma-noncoherent symbols for all swiotlb builds
The code like this:
ptr = kmalloc(size, GFP_KERNEL);
page = virt_to_page(ptr);
offset = offset_in_page(ptr);
kfree(page_address(page) + offset);
may produce false-positive invalid-free reports on the kernel with
CONFIG_KASAN_SW_TAGS=y.
In the example above we lose the original tag assigned to 'ptr', so
kfree() gets the pointer with 0xFF tag. In kfree() we check that 0xFF
tag is different from the tag in shadow hence print false report.
Instead of just comparing tags, do the following:
1) Check that shadow doesn't contain KASAN_TAG_INVALID. Otherwise it's
double-free and it doesn't matter what tag the pointer have.
2) If pointer tag is different from 0xFF, make sure that tag in the
shadow is the same as in the pointer.
Link: http://lkml.kernel.org/r/20190819172540.19581-1-aryabinin@virtuozzo.com
Fixes: 7f94ffbc4c ("kasan: add hooks implementation for tag-based mode")
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reported-by: Walter Wu <walter-zh.wu@mediatek.com>
Reported-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In zs_destroy_pool() we call flush_work(&pool->free_work). However, we
have no guarantee that migration isn't happening in the background at
that time.
Since migration can't directly free pages, it relies on free_work being
scheduled to free the pages. But there's nothing preventing an
in-progress migrate from queuing the work *after*
zs_unregister_migration() has called flush_work(). Which would mean
pages still pointing at the inode when we free it.
Since we know at destroy time all objects should be free, no new
migrations can come in (since zs_page_isolate() fails for fully-free
zspages). This means it is sufficient to track a "# isolated zspages"
count by class, and have the destroy logic ensure all such pages have
drained before proceeding. Keeping that state under the class spinlock
keeps the logic straightforward.
In this case a memory leak could lead to an eventual crash if compaction
hits the leaked page. This crash would only occur if people are
changing their zswap backend at runtime (which eventually starts
destruction).
Link: http://lkml.kernel.org/r/20190809181751.219326-2-henryburns@google.com
Fixes: 48b4800a1c ("zsmalloc: page migration support")
Signed-off-by: Henry Burns <henryburns@google.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Henry Burns <henrywolfeburns@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Jonathan Adams <jwadams@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>
In zs_page_migrate() we call putback_zspage() after we have finished
migrating all pages in this zspage. However, the return value is
ignored. If a zs_free() races in between zs_page_isolate() and
zs_page_migrate(), freeing the last object in the zspage,
putback_zspage() will leave the page in ZS_EMPTY for potentially an
unbounded amount of time.
To fix this, we need to do the same thing as zs_page_putback() does:
schedule free_work to occur.
To avoid duplicated code, move the sequence to a new
putback_zspage_deferred() function which both zs_page_migrate() and
zs_page_putback() call.
Link: http://lkml.kernel.org/r/20190809181751.219326-1-henryburns@google.com
Fixes: 48b4800a1c ("zsmalloc: page migration support")
Signed-off-by: Henry Burns <henryburns@google.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Henry Burns <henrywolfeburns@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Jonathan Adams <jwadams@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>
THP splitting path is missing the split_page_owner() call that
split_page() has.
As a result, split THP pages are wrongly reported in the page_owner file
as order-9 pages. Furthermore when the former head page is freed, the
remaining former tail pages are not listed in the page_owner file at
all. This patch fixes that by adding the split_page_owner() call into
__split_huge_page().
Link: http://lkml.kernel.org/r/20190820131828.22684-2-vbabka@suse.cz
Fixes: a9627bc5e3 ("mm/page_owner: introduce split_page_owner and replace manual handling")
Reported-by: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
userfaultfd_release() should clear vm_flags/vm_userfaultfd_ctx even if
mm->core_state != NULL.
Otherwise a page fault can see userfaultfd_missing() == T and use an
already freed userfaultfd_ctx.
Link: http://lkml.kernel.org/r/20190820160237.GB4983@redhat.com
Fixes: 04f5866e41 ("coredump: fix race condition between mmget_not_zero()/get_task_mm() and core dumping")
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Tested-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Jann Horn <jannh@google.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Only when calling the poll syscall the first time can user receive
POLLPRI correctly. After that, user always fails to acquire the event
signal.
Reproduce case:
1. Get the monitor code in Documentation/accounting/psi.txt
2. Run it, and wait for the event triggered.
3. Kill and restart the process.
The question is why we can end up with poll_scheduled = 1 but the work
not running (which would reset it to 0). And the answer is because the
scheduling side sees group->poll_kworker under RCU protection and then
schedules it, but here we cancel the work and destroy the worker. The
cancel needs to pair with resetting the poll_scheduled flag.
Link: http://lkml.kernel.org/r/1566357985-97781-1-git-send-email-joseph.qi@linux.alibaba.com
Signed-off-by: Jason Xing <kerneljasonxing@linux.alibaba.com>
Signed-off-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Caspar Zhang <caspar@linux.alibaba.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Similar to vmstats, percpu caching of local vmevents leads to an
accumulation of errors on non-leaf levels. This happens because some
leftovers may remain in percpu caches, so that they are never propagated
up by the cgroup tree and just disappear into nonexistence with on
releasing of the memory cgroup.
To fix this issue let's accumulate and propagate percpu vmevents values
before releasing the memory cgroup similar to what we're doing with
vmstats.
Since on cpu hotplug we do flush percpu vmstats anyway, we can iterate
only over online cpus.
Link: http://lkml.kernel.org/r/20190819202338.363363-4-guro@fb.com
Fixes: 42a3003535 ("mm: memcontrol: fix recursive statistics correctness & scalabilty")
Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Percpu caching of local vmstats with the conditional propagation by the
cgroup tree leads to an accumulation of errors on non-leaf levels.
Let's imagine two nested memory cgroups A and A/B. Say, a process
belonging to A/B allocates 100 pagecache pages on the CPU 0. The percpu
cache will spill 3 times, so that 32*3=96 pages will be accounted to A/B
and A atomic vmstat counters, 4 pages will remain in the percpu cache.
Imagine A/B is nearby memory.max, so that every following allocation
triggers a direct reclaim on the local CPU. Say, each such attempt will
free 16 pages on a new cpu. That means every percpu cache will have -16
pages, except the first one, which will have 4 - 16 = -12. A/B and A
atomic counters will not be touched at all.
Now a user removes A/B. All percpu caches are freed and corresponding
vmstat numbers are forgotten. A has 96 pages more than expected.
As memory cgroups are created and destroyed, errors do accumulate. Even
1-2 pages differences can accumulate into large numbers.
To fix this issue let's accumulate and propagate percpu vmstat values
before releasing the memory cgroup. At this point these numbers are
stable and cannot be changed.
Since on cpu hotplug we do flush percpu vmstats anyway, we can iterate
only over online cpus.
Link: http://lkml.kernel.org/r/20190819202338.363363-2-guro@fb.com
Fixes: 42a3003535 ("mm: memcontrol: fix recursive statistics correctness & scalabilty")
Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 0cfaee2af3 ("include/asm-generic/5level-fixup.h: fix variable
'p4d' set but not used") converted a few functions from macros to static
inline, which causes parisc to complain,
In file included from include/asm-generic/4level-fixup.h:38:0,
from arch/parisc/include/asm/pgtable.h:5,
from arch/parisc/include/asm/io.h:6,
from include/linux/io.h:13,
from sound/core/memory.c:9:
include/asm-generic/5level-fixup.h:14:18: error: unknown type name 'pgd_t'; did you mean 'pid_t'?
#define p4d_t pgd_t
^
include/asm-generic/5level-fixup.h:24:28: note: in expansion of macro 'p4d_t'
static inline int p4d_none(p4d_t p4d)
^~~~~
It is because "4level-fixup.h" is included before "asm/page.h" where
"pgd_t" is defined.
Link: http://lkml.kernel.org/r/20190815205305.1382-1-cai@lca.pw
Fixes: 0cfaee2af3 ("include/asm-generic/5level-fixup.h: fix variable 'p4d' set but not used")
Signed-off-by: Qian Cai <cai@lca.pw>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After commit 907ec5fca3 ("mm: zero remaining unavailable struct
pages"), struct page of reserved memory is zeroed. This causes
page->flags to be 0 and fixes issues related to reading
/proc/kpageflags, for example, of reserved memory.
The VM_BUG_ON() in move_freepages_block(), however, assumes that
page_zone() is meaningful even for reserved memory. That assumption is
no longer true after the aforementioned commit.
There's no reason why move_freepages_block() should be testing the
legitimacy of page_zone() for reserved memory; its scope is limited only
to pages on the zone's freelist.
Note that pfn_valid() can be true for reserved memory: there is a
backing struct page. The check for page_to_nid(page) is also buggy but
reserved memory normally only appears on node 0 so the zeroing doesn't
affect this.
Move the debug checks to after verifying PageBuddy is true. This
isolates the scope of the checks to only be for buddy pages which are on
the zone's freelist which move_freepages_block() is operating on. In
this case, an incorrect node or zone is a bug worthy of being warned
about (and the examination of struct page is acceptable bcause this
memory is not reserved).
Why does move_freepages_block() gets called on reserved memory? It's
simply math after finding a valid free page from the per-zone free area
to use as fallback. We find the beginning and end of the pageblock of
the valid page and that can bring us into memory that was reserved per
the e820. pfn_valid() is still true (it's backed by a struct page), but
since it's zero'd we shouldn't make any inferences here about comparing
its node or zone. The current node check just happens to succeed most
of the time by luck because reserved memory typically appears on node 0.
The fix here is to validate that we actually have buddy pages before
testing if there's any type of zone or node strangeness going on.
We noticed it almost immediately after bringing 907ec5fca3 in on
CONFIG_DEBUG_VM builds. It depends on finding specific free pages in
the per-zone free area where the math in move_freepages() will bring the
start or end pfn into reserved memory and wanting to claim that entire
pageblock as a new migratetype. So the path will be rare, require
CONFIG_DEBUG_VM, and require fallback to a different migratetype.
Some struct pages were already zeroed from reserve pages before
907ec5fca3c so it theoretically could trigger before this commit. I
think it's rare enough under a config option that most people don't run
that others may not have noticed. I wouldn't argue against a stable tag
and the backport should be easy enough, but probably wouldn't single out
a commit that this is fixing.
Mel said:
: The overhead of the debugging check is higher with this patch although
: it'll only affect debug builds and the path is not particularly hot.
: If this was a concern, I think it would be reasonable to simply remove
: the debugging check as the zone boundaries are checked in
: move_freepages_block and we never expect a zone/node to be smaller than
: a pageblock and stuck in the middle of another zone.
Link: http://lkml.kernel.org/r/alpine.DEB.2.21.1908122036560.10779@chino.kir.corp.google.com
Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pavel Tatashin <pavel.tatashin@microsoft.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In z3fold_destroy_pool() we call destroy_workqueue(&pool->compact_wq).
However, we have no guarantee that migration isn't happening in the
background at that time.
Migration directly calls queue_work_on(pool->compact_wq), if destruction
wins that race we are using a destroyed workqueue.
Link: http://lkml.kernel.org/r/20190809213828.202833-1-henryburns@google.com
Signed-off-by: Henry Burns <henryburns@google.com>
Cc: Vitaly Wool <vitalywool@gmail.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Jonathan Adams <jwadams@google.com>
Cc: Henry Burns <henrywolfeburns@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Fix not reporting open drain/source lines to userspace as "input"
- Fix a minor build error found in randconfigs
- Fix a chip select quirk on the Freescale SPI
- Fix the irqchip initialization semantic order to reflect what
it was using the old API
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Merge tag 'gpio-v5.3-4' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull GPIO fixes from Linus Walleij:
"Here is a (hopefully last) set of GPIO fixes for the v5.3 kernel
cycle. Two are pretty core:
- Fix not reporting open drain/source lines to userspace as "input"
- Fix a minor build error found in randconfigs
- Fix a chip select quirk on the Freescale SPI
- Fix the irqchip initialization semantic order to reflect what it
was using the old API"
* tag 'gpio-v5.3-4' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
gpio: Fix irqchip initialization order
gpio: of: fix Freescale SPI CS quirk handling
gpio: Fix build error of function redefinition
gpiolib: never report open-drain/source lines as 'input' to user-space
- Fix of a memory leak (and related cleanups) in the hyper-v keyboard
driver by Dexuan Cui.
- Code cleanups for hyper-v clocksource driver during the merge window
by Dexuan Cui.
- Fix for a false positive warning in the userspace hyper-v KVP store by
Vitaly Kuznetsov.
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Merge tag 'hyperv-fixes-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux
Pull Hyper-V fixes from Sasha Levin:
- Fix for panics and network failures on PAE guests by Dexuan Cui.
- Fix of a memory leak (and related cleanups) in the hyper-v keyboard
driver by Dexuan Cui.
- Code cleanups for hyper-v clocksource driver during the merge window
by Dexuan Cui.
- Fix for a false positive warning in the userspace hyper-v KVP store
by Vitaly Kuznetsov.
* tag 'hyperv-fixes-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
Drivers: hv: vmbus: Fix virt_to_hvpfn() for X86_PAE
Tools: hv: kvp: eliminate 'may be used uninitialized' warning
Input: hyperv-keyboard: Use in-place iterator API in the channel callback
Drivers: hv: vmbus: Remove the unused "tsc_page" from struct hv_context
- Two KVM fixes for MMIO emulation and UBSAN
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Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Will Deacon:
"Two KVM/arm fixes for MMIO emulation and UBSAN.
Unusually, we're routing them via the arm64 tree as per Paolo's
request on the list:
https://lore.kernel.org/kvm/21ae69a2-2546-29d0-bff6-2ea825e3d968@redhat.com/
We don't actually have any other arm64 fixes pending at the moment
(touch wood), so I've pulled from Marc, written a merge commit, tagged
the result and run it through my build/boot/bisect scripts"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
KVM: arm/arm64: VGIC: Properly initialise private IRQ affinity
KVM: arm/arm64: Only skip MMIO insn once
Four fixes, three for edge conditions which don't occur very often.
The lpfc fix mitigates memory exhaustion for some high CPU systems.
Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"Four fixes, three for edge conditions which don't occur very often.
The lpfc fix mitigates memory exhaustion for some high CPU systems"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: lpfc: Mitigate high memory pre-allocation by SCSI-MQ
scsi: ufs: Fix NULL pointer dereference in ufshcd_config_vreg_hpm()
scsi: target: tcmu: avoid use-after-free after command timeout
scsi: qla2xxx: Fix gnl.l memory leak on adapter init failure
- Fix a forgotten inode unlock when chown/chgrp fail due to quota.
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Merge tag 'xfs-5.3-fixes-6' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs fix from Darrick Wong:
"A single patch that fixes a xfs lockup problem when a chown/chgrp
operation fails due to running out of quota. It has survived the usual
xfstests runs and merges cleanly with this morning's master:
- Fix a forgotten inode unlock when chown/chgrp fail due to quota"
* tag 'xfs-5.3-fixes-6' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: fix missing ILOCK unlock when xfs_setattr_nonsize fails due to EDQUOT
Miklos Szeredi
Eric Biggers
David Howells
Al Viro
Maxim Patlasov
Kirill Smelkov
Linus Torvalds
Andrey Ryabinin
Henry Burns
Vlastimil Babka
Oleg Nesterov
Jason Xing
Roman Gushchin
Qian Cai
David Rientjes