If the first request allocated and issued by a process is a passhthrough
request, we don't set up an IO context for it. Ensure that
blk_mq_sched_assign_ioc() ignores a NULL io_context.
Fixes: e2b3fa5af7 ("block: Remove bio->bi_ioc")
Reported-by: Ming Lei <ming.lei@redhat.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
For the synchronous I/O path case (read(), write() etc system calls), a
BIO I/O priority is not initialized until the execution of
blk_init_request_from_bio() when the BIO is submitted and a request
initialized for the BIO execution. This is due to the ki_ioprio field of
the struct kiocb defined on stack being always initialized to
IOPRIO_CLASS_NONE, regardless of the calling process I/O context ioprio
value set with ioprio_set(). This late initialization can result in the
BIO being merged to pending requests even when the I/O priorities
differ.
Fix this by initializing the ki_iopriority field of on stack struct
kiocb using the get_current_ioprio() helper, ensuring that all BIOs
allocated and submitted for the system call execution see the correct
intended I/O priority early. With this, since a BIO I/O priority is
always set to the intended effective value for both the sync and async
path, blk_init_request_from_bio() can be simplified.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Adam Manzanares <adam.manzanares@wdc.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Growing in size a high priority request by merging it with a lower
priority BIO or request will increase the request execution time. This
is the opposite result of the desired effect of high I/O priorities,
namely getting low I/O latencies. Prevent merging of requests and BIOs
that have different I/O priorities to fix this.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
For cases when the application does not specify aio_reqprio for an aio,
fallback to use get_current_ioprio() to obtain the task I/O priority
last set using ioprio_set() rather than the hardcoded IOPRIO_CLASS_NONE
value.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Adam Manzanares <adam.manzanares@wdc.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Define get_current_ioprio() as an inline helper to obtain the caller
I/O priority from its task I/O context. Use this helper in
blk_init_request_from_bio() to set a request ioprio.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
bio->bi_ioc is never set so always NULL. Remove references to it in
bio_disassociate_task() and in rq_ioc() and delete this field from
struct bio. With this change, rq_ioc() always returns
current->io_context without the need for a bio argument. Further
simplify the code and make it more readable by also removing this
helper, which also allows to simplify blk_mq_sched_assign_ioc() by
removing its bio argument.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Adam Manzanares <adam.manzanares@wdc.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Comment the use of the IOCB_FLAG_IOPRIO aio flag similarly to the
IOCB_FLAG_RESFD flag.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
It's specifically looking for a given request, which we will not be
supporting going forward. Also kill the qla2xxx poll implementation
as that's the only user of the nvme-fc poll, and the now unused
->poll_queue() hook.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We currently only really support sync poll, ie poll with 1 IO in flight.
This prepares us for supporting async poll.
Note that the returned value isn't necessarily 100% accurate. If poll
races with IRQ completion, we assume that the fact that the task is now
runnable means we found at least one entry. In reality it could be more
than 1, or not even 1. This is fine, the caller will just need to take
this into account.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
For the core poll helper, the task state setting don't need to imply any
atomics, as it's the current task itself that is being modified and
we're not going to sleep.
For IRQ driven, the wakeup path have the necessary barriers to not need
us using the heavy handed version of the task state setting.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We need a better way of configuring this, and given that polling is
(still) a bit niche, let's default to using 0 poll queues. That way
we'll have the same read/write/poll behavior as 4.20, and users that
want to test/use polling are required to do manual configuration of the
number of poll queues.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'v4.20-rc3' into for-4.21/block
Merge in -rc3 to resolve a few conflicts, but also to get a few
important fixes that have gone into mainline since the block
4.21 branch was forked off (most notably the SCSI queue issue,
which is both a conflict AND needed fix).
Signed-off-by: Jens Axboe <axboe@kernel.dk>
With the locking removed, it's unused. Kill it.
Fixes: 503f620f0c ("floppy: remove queue_lock around floppy_end_request")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
- Address Range Scrub overflow continuation handling has been broken
since it was initially merged. It was only recently that error injection
and platform-BIOS support enabled this corner case to be exercised.
- The recent attempt to provide more isolation for the kernel Address
Range Scrub state machine from userapace initiated sessions triggers a
lockdep report. Revert and try again at the next merge window.
- Fix a kasan reported buffer overflow in libnvdimm unit test
infrastrucutre (nfit_test)
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Merge tag 'libnvdimm-fixes-4.20-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm fixes from Dan Williams:
"A small batch of fixes for v4.20-rc3.
The overflow continuation fix addresses something that has been broken
for several releases. Arguably it could wait even longer, but it's a
one line fix and this finishes the last of the known address range
scrub bug reports. The revert addresses a lockdep regression. The unit
tests are not critical to fix, but no reason to hold this fix back.
Summary:
- Address Range Scrub overflow continuation handling has been broken
since it was initially merged. It was only recently that error
injection and platform-BIOS support enabled this corner case to be
exercised.
- The recent attempt to provide more isolation for the kernel Address
Range Scrub state machine from userapace initiated sessions
triggers a lockdep report. Revert and try again at the next merge
window.
- Fix a kasan reported buffer overflow in libnvdimm unit test
infrastrucutre (nfit_test)"
* tag 'libnvdimm-fixes-4.20-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
Revert "acpi, nfit: Further restrict userspace ARS start requests"
acpi, nfit: Fix ARS overflow continuation
tools/testing/nvdimm: Fix the array size for dimm devices.
Merge misc fixes from Andrew Morton:
"16 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm/memblock.c: fix a typo in __next_mem_pfn_range() comments
mm, page_alloc: check for max order in hot path
scripts/spdxcheck.py: make python3 compliant
tmpfs: make lseek(SEEK_DATA/SEK_HOLE) return ENXIO with a negative offset
lib/ubsan.c: don't mark __ubsan_handle_builtin_unreachable as noreturn
mm/vmstat.c: fix NUMA statistics updates
mm/gup.c: fix follow_page_mask() kerneldoc comment
ocfs2: free up write context when direct IO failed
scripts/faddr2line: fix location of start_kernel in comment
mm: don't reclaim inodes with many attached pages
mm, memory_hotplug: check zone_movable in has_unmovable_pages
mm/swapfile.c: use kvzalloc for swap_info_struct allocation
MAINTAINERS: update OMAP MMC entry
hugetlbfs: fix kernel BUG at fs/hugetlbfs/inode.c:444!
kernel/sched/psi.c: simplify cgroup_move_task()
z3fold: fix possible reclaim races
Pull scheduler fix from Ingo Molnar:
"Fix an exec() related scalability/performance regression, which was
caused by incorrectly calculating load and migrating tasks on exec()
when they shouldn't be"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Fix cpu_util_wake() for 'execl' type workloads
Pull perf fixes from Ingo Molnar:
"Fix uncore PMU enumeration for CofeeLake CPUs"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel/uncore: Support CoffeeLake 8th CBOX
perf/x86/intel/uncore: Add more IMC PCI IDs for KabyLake and CoffeeLake CPUs
Pull EFI fixes from Ingo Molnar:
"Misc fixes: two warning splat fixes, a leak fix and persistent memory
allocation fixes for ARM"
* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efi: Permit calling efi_mem_reserve_persistent() from atomic context
efi/arm: Defer persistent reservations until after paging_init()
efi/arm/libstub: Pack FDT after populating it
efi/arm: Revert deferred unmap of early memmap mapping
efi: Fix debugobjects warning on 'efi_rts_work'
Pull ARM spectre updates from Russell King:
"These are the currently known final bits that resolve the Spectre
issues. big.Little systems used to be sufficiently identical in that
there were no differences between individual CPUs in the system that
mattered to the kernel. With the advent of the Spectre problem, the
CPUs now have differences in how the workaround is applied.
As a result of previous Spectre patches, these systems ended up
reporting quite a lot of:
"CPUx: Spectre v2: incorrect context switching function, system vulnerable"
messages due to the action of the big.Little switcher causing the CPUs
to be re-initialised regularly. This series resolves that issue by
making the CPU vtable unique to each CPU.
However, since this is used very early, before per-cpu is setup,
per-cpu can't be used. We also have a problem that two of the methods
are not called from preempt-safe paths, but thankfully these remain
identical between all CPUs in the system. To make sure, we validate
that these are identical during boot"
* 'spectre' of git://git.armlinux.org.uk/~rmk/linux-arm:
ARM: spectre-v2: per-CPU vtables to work around big.Little systems
ARM: add PROC_VTABLE and PROC_TABLE macros
ARM: clean up per-processor check_bugs method call
ARM: split out processor lookup
ARM: make lookup_processor_type() non-__init
Konstantin has noticed that kvmalloc might trigger the following
warning:
WARNING: CPU: 0 PID: 6676 at mm/vmstat.c:986 __fragmentation_index+0x54/0x60
[...]
Call Trace:
fragmentation_index+0x76/0x90
compaction_suitable+0x4f/0xf0
shrink_node+0x295/0x310
node_reclaim+0x205/0x250
get_page_from_freelist+0x649/0xad0
__alloc_pages_nodemask+0x12a/0x2a0
kmalloc_large_node+0x47/0x90
__kmalloc_node+0x22b/0x2e0
kvmalloc_node+0x3e/0x70
xt_alloc_table_info+0x3a/0x80 [x_tables]
do_ip6t_set_ctl+0xcd/0x1c0 [ip6_tables]
nf_setsockopt+0x44/0x60
SyS_setsockopt+0x6f/0xc0
do_syscall_64+0x67/0x120
entry_SYSCALL_64_after_hwframe+0x3d/0xa2
the problem is that we only check for an out of bound order in the slow
path and the node reclaim might happen from the fast path already. This
is fixable by making sure that kvmalloc doesn't ever use kmalloc for
requests that are larger than KMALLOC_MAX_SIZE but this also shows that
the code is rather fragile. A recent UBSAN report just underlines that
by the following report
UBSAN: Undefined behaviour in mm/page_alloc.c:3117:19
shift exponent 51 is too large for 32-bit type 'int'
CPU: 0 PID: 6520 Comm: syz-executor1 Not tainted 4.19.0-rc2 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0xd2/0x148 lib/dump_stack.c:113
ubsan_epilogue+0x12/0x94 lib/ubsan.c:159
__ubsan_handle_shift_out_of_bounds+0x2b6/0x30b lib/ubsan.c:425
__zone_watermark_ok+0x2c7/0x400 mm/page_alloc.c:3117
zone_watermark_fast mm/page_alloc.c:3216 [inline]
get_page_from_freelist+0xc49/0x44c0 mm/page_alloc.c:3300
__alloc_pages_nodemask+0x21e/0x640 mm/page_alloc.c:4370
alloc_pages_current+0xcc/0x210 mm/mempolicy.c:2093
alloc_pages include/linux/gfp.h:509 [inline]
__get_free_pages+0x12/0x60 mm/page_alloc.c:4414
dma_mem_alloc+0x36/0x50 arch/x86/include/asm/floppy.h:156
raw_cmd_copyin drivers/block/floppy.c:3159 [inline]
raw_cmd_ioctl drivers/block/floppy.c:3206 [inline]
fd_locked_ioctl+0xa00/0x2c10 drivers/block/floppy.c:3544
fd_ioctl+0x40/0x60 drivers/block/floppy.c:3571
__blkdev_driver_ioctl block/ioctl.c:303 [inline]
blkdev_ioctl+0xb3c/0x1a30 block/ioctl.c:601
block_ioctl+0x105/0x150 fs/block_dev.c:1883
vfs_ioctl fs/ioctl.c:46 [inline]
do_vfs_ioctl+0x1c0/0x1150 fs/ioctl.c:687
ksys_ioctl+0x9e/0xb0 fs/ioctl.c:702
__do_sys_ioctl fs/ioctl.c:709 [inline]
__se_sys_ioctl fs/ioctl.c:707 [inline]
__x64_sys_ioctl+0x7e/0xc0 fs/ioctl.c:707
do_syscall_64+0xc4/0x510 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Note that this is not a kvmalloc path. It is just that the fast path
really depends on having sanitzed order as well. Therefore move the
order check to the fast path.
Link: http://lkml.kernel.org/r/20181113094305.GM15120@dhcp22.suse.cz
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reported-by: Kyungtae Kim <kt0755@gmail.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Pavel Tatashin <pavel.tatashin@microsoft.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Aaron Lu <aaron.lu@intel.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Byoungyoung Lee <lifeasageek@gmail.com>
Cc: "Dae R. Jeong" <threeearcat@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Without this change the following happens when using Python3 (3.6.6):
$ echo "GPL-2.0" | python3 scripts/spdxcheck.py -
FAIL: 'str' object has no attribute 'decode'
Traceback (most recent call last):
File "scripts/spdxcheck.py", line 253, in <module>
parser.parse_lines(sys.stdin, args.maxlines, '-')
File "scripts/spdxcheck.py", line 171, in parse_lines
line = line.decode(locale.getpreferredencoding(False), errors='ignore')
AttributeError: 'str' object has no attribute 'decode'
So as the line is already a string, there is no need to decode it and
the line can be dropped.
/usr/bin/python on Arch is Python 3. So this would indeed be worth
going into 4.19.
Link: http://lkml.kernel.org/r/20181023070802.22558-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Joe Perches <joe@perches.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Other filesystems such as ext4, f2fs and ubifs all return ENXIO when
lseek (SEEK_DATA or SEEK_HOLE) requests a negative offset.
man 2 lseek says
: EINVAL whence is not valid. Or: the resulting file offset would be
: negative, or beyond the end of a seekable device.
:
: ENXIO whence is SEEK_DATA or SEEK_HOLE, and the file offset is beyond
: the end of the file.
Make tmpfs return ENXIO under these circumstances as well. After this,
tmpfs also passes xfstests's generic/448.
[akpm@linux-foundation.org: rewrite changelog]
Link: http://lkml.kernel.org/r/1540434176-14349-1-git-send-email-yuyufen@huawei.com
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Hugh Dickins <hughd@google.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
gcc-8 complains about the prototype for this function:
lib/ubsan.c:432:1: error: ignoring attribute 'noreturn' in declaration of a built-in function '__ubsan_handle_builtin_unreachable' because it conflicts with attribute 'const' [-Werror=attributes]
This is actually a GCC's bug. In GCC internals
__ubsan_handle_builtin_unreachable() declared with both 'noreturn' and
'const' attributes instead of only 'noreturn':
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84210
Workaround this by removing the noreturn attribute.
[aryabinin: add information about GCC bug in changelog]
Link: http://lkml.kernel.org/r/20181107144516.4587-1-aryabinin@virtuozzo.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Acked-by: Olof Johansson <olof@lixom.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Scan through the whole array to see if an update is needed. While we're
at it, use sizeof() to be safe against any possible type changes in the
future.
The bug here is that we wouldn't sync per-cpu counters into global ones
if there was an update of numa_stats for higher cpus. Highly
theoretical one though because it is much more probable that zone_stats
are updated so we would refresh anyway. So I wouldn't bother to mark
this for stable, yet something nice to fix.
[mhocko@suse.com: changelog enhancement]
Link: http://lkml.kernel.org/r/1541601517-17282-1-git-send-email-janne.huttunen@nokia.com
Fixes: 1d90ca897c ("mm: update NUMA counter threshold size")
Signed-off-by: Janne Huttunen <janne.huttunen@nokia.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit df06b37ffe ("mm/gup: cache dev_pagemap while pinning pages")
modified the signature of follow_page_mask() but left the parameter
description behind.
Update the description to make the code and comments agree again.
While at it, update formatting of the return value description to match
Documentation/doc-guide/kernel-doc.rst guidelines.
Link: http://lkml.kernel.org/r/1541603316-27832-1-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The write context should also be freed even when direct IO failed.
Otherwise a memory leak is introduced and entries remain in
oi->ip_unwritten_list causing the following BUG later in unlink path:
ERROR: bug expression: !list_empty(&oi->ip_unwritten_list)
ERROR: Clear inode of 215043, inode has unwritten extents
...
Call Trace:
? __set_current_blocked+0x42/0x68
ocfs2_evict_inode+0x91/0x6a0 [ocfs2]
? bit_waitqueue+0x40/0x33
evict+0xdb/0x1af
iput+0x1a2/0x1f7
do_unlinkat+0x194/0x28f
SyS_unlinkat+0x1b/0x2f
do_syscall_64+0x79/0x1ae
entry_SYSCALL_64_after_hwframe+0x151/0x0
This patch also logs, with frequency limit, direct IO failures.
Link: http://lkml.kernel.org/r/20181102170632.25921-1-wen.gang.wang@oracle.com
Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com>
Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Changwei Ge <ge.changwei@h3c.com>
Reviewed-by: Joseph Qi <jiangqi903@gmail.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Spock reported that commit 172b06c32b ("mm: slowly shrink slabs with a
relatively small number of objects") leads to a regression on his setup:
periodically the majority of the pagecache is evicted without an obvious
reason, while before the change the amount of free memory was balancing
around the watermark.
The reason behind is that the mentioned above change created some
minimal background pressure on the inode cache. The problem is that if
an inode is considered to be reclaimed, all belonging pagecache page are
stripped, no matter how many of them are there. So, if a huge
multi-gigabyte file is cached in the memory, and the goal is to reclaim
only few slab objects (unused inodes), we still can eventually evict all
gigabytes of the pagecache at once.
The workload described by Spock has few large non-mapped files in the
pagecache, so it's especially noticeable.
To solve the problem let's postpone the reclaim of inodes, which have
more than 1 attached page. Let's wait until the pagecache pages will be
evicted naturally by scanning the corresponding LRU lists, and only then
reclaim the inode structure.
Link: http://lkml.kernel.org/r/20181023164302.20436-1-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Reported-by: Spock <dairinin@gmail.com>
Tested-by: Spock <dairinin@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: <stable@vger.kernel.org> [4.19.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Page state checks are racy. Under a heavy memory workload (e.g. stress
-m 200 -t 2h) it is quite easy to hit a race window when the page is
allocated but its state is not fully populated yet. A debugging patch to
dump the struct page state shows
has_unmovable_pages: pfn:0x10dfec00, found:0x1, count:0x0
page:ffffea0437fb0000 count:1 mapcount:1 mapping:ffff880e05239841 index:0x7f26e5000 compound_mapcount: 1
flags: 0x5fffffc0090034(uptodate|lru|active|head|swapbacked)
Note that the state has been checked for both PageLRU and PageSwapBacked
already. Closing this race completely would require some sort of retry
logic. This can be tricky and error prone (think of potential endless
or long taking loops).
Workaround this problem for movable zones at least. Such a zone should
only contain movable pages. Commit 15c30bc090 ("mm, memory_hotplug:
make has_unmovable_pages more robust") has told us that this is not
strictly true though. Bootmem pages should be marked reserved though so
we can move the original check after the PageReserved check. Pages from
other zones are still prone to races but we even do not pretend that
memory hotremove works for those so pre-mature failure doesn't hurt that
much.
Link: http://lkml.kernel.org/r/20181106095524.14629-1-mhocko@kernel.org
Fixes: 15c30bc090 ("mm, memory_hotplug: make has_unmovable_pages more robust")
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Baoquan He <bhe@redhat.com>
Tested-by: Baoquan He <bhe@redhat.com>
Acked-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit a2468cc9bf ("swap: choose swap device according to numa node")
changed 'avail_lists' field of 'struct swap_info_struct' to an array.
In popular linux distros it increased size of swap_info_struct up to 40
Kbytes and now swap_info_struct allocation requires order-4 page.
Switch to kvzmalloc allows to avoid unexpected allocation failures.
Link: http://lkml.kernel.org/r/fc23172d-3c75-21e2-d551-8b1808cbe593@virtuozzo.com
Fixes: a2468cc9bf ("swap: choose swap device according to numa node")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Acked-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Huang Ying <ying.huang@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jarkko's e-mail address hasn't worked for a long time. We still want to
keep this driver working as it is critical for some of the OMAP boards.
I use and test this driver frequently, so change myself as a maintainer
with "Odd Fixes" status.
Link: http://lkml.kernel.org/r/20181106222750.12939-1-aaro.koskinen@iki.fi
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This bug has been experienced several times by the Oracle DB team. The
BUG is in remove_inode_hugepages() as follows:
/*
* If page is mapped, it was faulted in after being
* unmapped in caller. Unmap (again) now after taking
* the fault mutex. The mutex will prevent faults
* until we finish removing the page.
*
* This race can only happen in the hole punch case.
* Getting here in a truncate operation is a bug.
*/
if (unlikely(page_mapped(page))) {
BUG_ON(truncate_op);
In this case, the elevated map count is not the result of a race.
Rather it was incorrectly incremented as the result of a bug in the huge
pmd sharing code. Consider the following:
- Process A maps a hugetlbfs file of sufficient size and alignment
(PUD_SIZE) that a pmd page could be shared.
- Process B maps the same hugetlbfs file with the same size and
alignment such that a pmd page is shared.
- Process B then calls mprotect() to change protections for the mapping
with the shared pmd. As a result, the pmd is 'unshared'.
- Process B then calls mprotect() again to chage protections for the
mapping back to their original value. pmd remains unshared.
- Process B then forks and process C is created. During the fork
process, we do dup_mm -> dup_mmap -> copy_page_range to copy page
tables. Copying page tables for hugetlb mappings is done in the
routine copy_hugetlb_page_range.
In copy_hugetlb_page_range(), the destination pte is obtained by:
dst_pte = huge_pte_alloc(dst, addr, sz);
If pmd sharing is possible, the returned pointer will be to a pte in an
existing page table. In the situation above, process C could share with
either process A or process B. Since process A is first in the list,
the returned pte is a pointer to a pte in process A's page table.
However, the check for pmd sharing in copy_hugetlb_page_range is:
/* If the pagetables are shared don't copy or take references */
if (dst_pte == src_pte)
continue;
Since process C is sharing with process A instead of process B, the
above test fails. The code in copy_hugetlb_page_range which follows
assumes dst_pte points to a huge_pte_none pte. It copies the pte entry
from src_pte to dst_pte and increments this map count of the associated
page. This is how we end up with an elevated map count.
To solve, check the dst_pte entry for huge_pte_none. If !none, this
implies PMD sharing so do not copy.
Link: http://lkml.kernel.org/r/20181105212315.14125-1-mike.kravetz@oracle.com
Fixes: c5c99429fa ("fix hugepages leak due to pagetable page sharing")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Prakash Sangappa <prakash.sangappa@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>
The existing code triggered an invalid warning about 'rq' possibly being
used uninitialized. Instead of doing the silly warning suppression by
initializa it to NULL, refactor the code to bail out early instead.
Warning was:
kernel/sched/psi.c: In function `cgroup_move_task':
kernel/sched/psi.c:639:13: warning: `rq' may be used uninitialized in this function [-Wmaybe-uninitialized]
Link: http://lkml.kernel.org/r/20181103183339.8669-1-olof@lixom.net
Fixes: 2ce7135adc ("psi: cgroup support")
Signed-off-by: Olof Johansson <olof@lixom.net>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Reclaim and free can race on an object which is basically fine but in
order for reclaim to be able to map "freed" object we need to encode
object length in the handle. handle_to_chunks() is then introduced to
extract object length from a handle and use it during mapping.
Moreover, to avoid racing on a z3fold "headless" page release, we should
not try to free that page in z3fold_free() if the reclaim bit is set.
Also, in the unlikely case of trying to reclaim a page being freed, we
should not proceed with that page.
While at it, fix the page accounting in reclaim function.
This patch supersedes "[PATCH] z3fold: fix reclaim lock-ups".
Link: http://lkml.kernel.org/r/20181105162225.74e8837d03583a9b707cf559@gmail.com
Signed-off-by: Vitaly Wool <vitaly.vul@sony.com>
Signed-off-by: Jongseok Kim <ks77sj@gmail.com>
Reported-by-by: Jongseok Kim <ks77sj@gmail.com>
Reviewed-by: Snild Dolkow <snild@sony.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace the lock in mmc_blk_data that is only used through a pointer
in struct mmc_queue and to protect fields in that structure with
an actual lock in struct mmc_queue.
Suggested-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'fsnotify_for_v4.20-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull fsnotify fix from Jan Kara:
"One small fsnotify fix for duplicate events"
* tag 'fsnotify_for_v4.20-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
fanotify: fix handling of events on child sub-directory
Pull bfs2 fixes from Andreas Gruenbacher:
"Fix two bugs leading to leaked buffer head references:
- gfs2: Put bitmap buffers in put_super
- gfs2: Fix iomap buffer head reference counting bug
And one bug leading to significant slow-downs when deleting large
files:
- gfs2: Fix metadata read-ahead during truncate (2)"
* tag 'gfs2-4.20.fixes3' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
gfs2: Fix iomap buffer head reference counting bug
gfs2: Fix metadata read-ahead during truncate (2)
gfs2: Put bitmap buffers in put_super
GFS2 passes the inode buffer head (dibh) from gfs2_iomap_begin to
gfs2_iomap_end in iomap->private. It sets that private pointer in
gfs2_iomap_get. Users of gfs2_iomap_get other than gfs2_iomap_begin
would have to release iomap->private, but this isn't done correctly,
leading to a leak of buffer head references.
To fix this, move the code for setting iomap->private from
gfs2_iomap_get to gfs2_iomap_begin.
Fixes: 64bc06bb32 ("gfs2: iomap buffered write support")
Cc: stable@vger.kernel.org # v4.19+
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull crypto fixes from Herbert Xu:
"This fixes the following issues:
- Potential memory overwrite in simd
- Kernel info leaks in crypto_user
- NULL dereference and use-after-free in hisilicon"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: user - Zeroize whole structure given to user space
crypto: user - fix leaking uninitialized memory to userspace
crypto: simd - correctly take reqsize of wrapped skcipher into account
crypto: hisilicon - Fix reference after free of memories on error path
crypto: hisilicon - Fix NULL dereference for same dst and src
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Merge tag 'drm-fixes-2018-11-16' of git://anongit.freedesktop.org/drm/drm
Pull drm fixes from Dave Airlie:
"Live from Vancouver, SoC maintainer talk, this weeks drm fixes pull
for rc3:
omapdrm:
- regression fixes for the reordering bridge stuff that went into rc1
i915:
- incorrect EU count fix
- HPD storm fix
- MST fix
- relocation fix for gen4/5
amdgpu:
- huge page handling fix
- IH ring setup
- XGMI aperture setup
- watermark setup fix
misc:
- docs and MST fix"
* tag 'drm-fixes-2018-11-16' of git://anongit.freedesktop.org/drm/drm: (23 commits)
drm/i915: Account for scale factor when calculating initial phase
drm/i915: Clean up skl_program_scaler()
drm/i915: Move programming plane scaler to its own function.
drm/i915/icl: Drop spurious register read from icl_dbuf_slices_update
drm/i915: fix broadwell EU computation
drm/amdgpu: fix huge page handling on Vega10
drm/amd/pp: Fix truncated clock value when set watermark
drm/amdgpu: fix bug with IH ring setup
drm/meson: venc: dmt mode must use encp
drm/amdgpu: set system aperture to cover whole FB region
drm/i915: Fix hpd handling for pins with two encoders
drm/i915/execlists: Force write serialisation into context image vs execution
drm/i915/icl: Fix power well 2 wrt. DC-off toggling order
drm/i915: Fix NULL deref when re-enabling HPD IRQs on systems with MST
drm/i915: Fix possible race in intel_dp_add_mst_connector()
drm/i915/ringbuffer: Delay after EMIT_INVALIDATE for gen4/gen5
drm/omap: dsi: Fix missing of_platform_depopulate()
drm/omap: Move DISPC runtime PM handling to omapdrm
drm/omap: dsi: Ensure the device is active during probe
drm/omap: hdmi4: Ensure the device is active during bind
...
blk_mq_stop_hw_queues doesn't need any locking, and the ide
dev_flags field isn't protected by it either.
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There is nothing we can synchronize against over a call to
blk_queue_dying.
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk_queue_max_hw_sectors can't do anything with queue_lock protection
so don't hold it.
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There is nothing the queue_lock could protect inside floppy_end_request,
so remove it.
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Two weeks worth of fixes since rc1.
- I broke 16-byte alignment of the stack when we moved PPR into pt_regs.
Despite being required by the ABI this broke almost nothing, we eventually
hit it in code where GCC does arithmetic on the stack pointer assuming the
bottom 4 bits are clear. Fix it by padding the in-kernel pt_regs by 8 bytes.
- A couple of commits fixing minor bugs in the recent SLB rewrite.
- A build fix related to tracepoints in KVM in some configurations.
- Our old "IO workarounds" code written for Cell couldn't coexist in a kernel
that runs on Power9 with the Radix MMU, fix that.
- Remove the NPU DMA ops, these just printed a warning and should never have
been called.
- Suppress an overly chatty message triggered by CPU hotplug in some configs.
- Two small selftest fixes.
Thanks to:
Alistair Popple, Gustavo Romero, Nicholas Piggin, Satheesh Rajendran, Scott Wood.
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Merge tag 'powerpc-4.20-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
"Two weeks worth of fixes since rc1.
- I broke 16-byte alignment of the stack when we moved PPR into
pt_regs. Despite being required by the ABI this broke almost
nothing, we eventually hit it in code where GCC does arithmetic on
the stack pointer assuming the bottom 4 bits are clear. Fix it by
padding the in-kernel pt_regs by 8 bytes.
- A couple of commits fixing minor bugs in the recent SLB rewrite.
- A build fix related to tracepoints in KVM in some configurations.
- Our old "IO workarounds" code written for Cell couldn't coexist in
a kernel that runs on Power9 with the Radix MMU, fix that.
- Remove the NPU DMA ops, these just printed a warning and should
never have been called.
- Suppress an overly chatty message triggered by CPU hotplug in some
configs.
- Two small selftest fixes.
Thanks to: Alistair Popple, Gustavo Romero, Nicholas Piggin, Satheesh
Rajendran, Scott Wood"
* tag 'powerpc-4.20-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
selftests/powerpc: Adjust wild_bctr to build with old binutils
powerpc/64: Fix kernel stack 16-byte alignment
powerpc/numa: Suppress "VPHN is not supported" messages
selftests/powerpc: Fix wild_bctr test to work on ppc64
powerpc/io: Fix the IO workarounds code to work with Radix
powerpc/mm/64s: Fix preempt warning in slb_allocate_kernel()
KVM: PPC: Move and undef TRACE_INCLUDE_PATH/FILE
powerpc/mm/64s: Only use slbfee on CPUs that support it
powerpc/mm/64s: Use PPC_SLBFEE macro
powerpc/mm/64s: Consolidate SLB assertions
powerpc/powernv/npu: Remove NPU DMA ops
Those will go straight to issue inside blk-mq, so don't bother
setting up a block plug for them.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Jens Axboe