[ Upstream commit 7c09c03091 ]
Deleting a subvolume on a full filesystem leads to ENOSPC followed by a
forced read-only. This is not a transaction abort and the filesystem is
otherwise ok, so the error should be just propagated to the callers.
This is caused by unnecessary call to btrfs_handle_fs_error for all
errors, except EAGAIN. This does not make sense as the standard
transaction abort mechanism is in btrfs_drop_snapshot so all relevant
failures are handled.
Originally in commit cb1b69f450 ("Btrfs: forced readonly when
btrfs_drop_snapshot() fails") there was no return value at all, so the
btrfs_std_error made some sense but once the error handling and
propagation has been implemented we don't need it anymore.
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 1c0e69ae1b ]
If the SS PHY is in P3, there is no pipe_clk, HW may use suspend_clk
for function, as suspend_clk is slow so EP command need more time to
complete, e.g, imx8M suspend_clk is 32K, set ep configuration will
take about 380us per below trace time stamp(44.286278 - 44.285897
= 0.000381):
configfs_acm.sh-822 [000] d..1 44.285896: dwc3_writel: addr
000000006d59aae1 value 00000401
configfs_acm.sh-822 [000] d..1 44.285897: dwc3_readl: addr
000000006d59aae1 value 00000401
... ...
configfs_acm.sh-822 [000] d..1 44.286278: dwc3_readl: addr
000000006d59aae1 value 00000001
configfs_acm.sh-822 [000] d..1 44.286279: dwc3_gadget_ep_cmd:
ep0out: cmd 'Set Endpoint Configuration' [401] params 00001000
00000500 00000000 --> status: Successful
This was originally found on Hisilicon Kirin Soc that need more time
for the device controller to clear the CmdAct of DEPCMD.
Signed-off-by: Yu Chen <chenyu56@huawei.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Li Jun <jun.li@nxp.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 48021f9813 ]
If uboot passes a blank string to console_setup then it results in
a trashed memory. Ultimately, the kernel crashes during freeing up
the memory.
This fix checks if there is a blank parameter being
passed to console_setup from uboot. In case it detects that
the console parameter is blank then it doesn't setup the serial
device and it gracefully exits.
Link: https://lore.kernel.org/r/20200522065306.83-1-shreyas.joshi@biamp.com
Signed-off-by: Shreyas Joshi <shreyas.joshi@biamp.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
[pmladek@suse.com: Better format the commit message and code, remove unnecessary brackets.]
Signed-off-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit dc455f4c88 ]
pm_runtime_get_sync() increments the runtime PM usage counter even
the call returns an error code. Thus a pairing decrement is needed
on the error handling path to keep the counter balanced.
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d7372dfb3f ]
pm_runtime_get_sync() increments the runtime PM usage counter even
the call returns an error code. Thus a pairing decrement is needed
on the error handling path to keep the counter balanced.
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 00583fbe80 ]
pm_runtime_get_sync() increments the runtime PM usage counter even
the call returns an error code. Thus a pairing decrement is needed
on the error handling path to keep the counter balanced.
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 49ee3c2ab5 ]
We are seeing a deadlock in e1000 down when NAPI is being disabled. Looking
over the kernel function trace of the system it appears that the interface
is being closed and then a reset is hitting which deadlocks the interface
as the NAPI interface is already disabled.
To prevent this from happening I am disabling the reset task when
__E1000_DOWN is already set. In addition code has been added so that we set
the __E1000_DOWN while holding the __E1000_RESET flag in e1000_close in
order to guarantee that the reset task will not run after we have started
the close call.
Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Tested-by: Maxim Zhukov <mussitantesmortem@gmail.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit a7f40c233a ]
The comparison of hcd->irq to less than zero for an error check will
never be true because hcd->irq is an unsigned int. Fix this by
assigning the int retval to the return of platform_get_irq and checking
this for the -ve error condition and assigning hcd->irq to retval.
Addresses-Coverity: ("Unsigned compared against 0")
Fixes: c856b4b0fd ("USB: EHCI: ehci-mv: fix error handling in mv_ehci_probe()")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20200515165453.104028-1-colin.king@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 32f98877c5 ]
page_count() is unstable. Unless there has been an RCU grace period
between when the page was removed from the page cache and now, a
speculative reference may exist from the page cache.
Reported-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c637fa1512 ]
The unsol event handling code has a loop retrieving the read/write
indices and the arrays without locking while the append to the array
may happen concurrently. This may lead to some inconsistency.
Although there hasn't been any proof of this bad results, it's still
safer to protect the racy accesses.
This patch adds the spinlock protection around the unsol handling loop
for addressing it. Here we take bus->reg_lock as the writer side
snd_hdac_bus_queue_event() is also protected by that lock.
Link: https://lore.kernel.org/r/20200516062556.30951-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7d31676a8d ]
Some variants of the samsung tty driver can pick which clock
to use for their baud rate generation. In the DT conversion,
a default clock was selected to be used if a specific one wasn't
assigned and then a comparison of which clock rate worked better
was done. Unfortunately, the comparison was implemented in such
a way that only the default clock was ever actually compared.
Fix this by iterating through all possible clocks, except when a
specific clock has already been picked via clk_sel (which is
only possible via board files).
Signed-off-by: Jonathan Bakker <xc-racer2@live.ca>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/BN6PR04MB06604E63833EA41837EBF77BA3A30@BN6PR04MB0660.namprd04.prod.outlook.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0771d7df81 ]
Upon receipt of a service subscription request from user via a topology
connection, one 'sub' object will be allocated in kernel, so it will be
able to send an event of the service if any to the user correspondingly
then. Also, in case of any failure, the connection will be shutdown and
all the pertaining 'sub' objects will be freed.
However, there is a race condition as follows resulting in memory leak:
receive-work connection send-work
| | |
sub-1 |<------//-------| |
sub-2 |<------//-------| |
| |<---------------| evt for sub-x
sub-3 |<------//-------| |
: : :
: : :
| /--------| |
| | * peer closed |
| | | |
| | |<-------X-------| evt for sub-y
| | |<===============|
sub-n |<------/ X shutdown |
-> orphan | |
That is, the 'receive-work' may get the last subscription request while
the 'send-work' is shutting down the connection due to peer close.
We had a 'lock' on the connection, so the two actions cannot be carried
out simultaneously. If the last subscription is allocated e.g. 'sub-n',
before the 'send-work' closes the connection, there will be no issue at
all, the 'sub' objects will be freed. In contrast the last subscription
will become orphan since the connection was closed, and we released all
references.
This commit fixes the issue by simply adding one test if the connection
remains in 'connected' state right after we obtain the connection lock,
then a subscription object can be created as usual, otherwise we ignore
it.
Acked-by: Ying Xue <ying.xue@windriver.com>
Acked-by: Jon Maloy <jmaloy@redhat.com>
Reported-by: Thang Ngo <thang.h.ngo@dektech.com.au>
Signed-off-by: Tuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit adf1d69264 ]
After sending Inquiry Cancel command to the controller, it is possible
that Inquiry Complete event comes before Inquiry Cancel command complete
event. In this case the Inquiry Cancel command will have status of
Command Disallowed since there is no Inquiry session to be cancelled.
This case should not be treated as error, otherwise we can reach an
inconsistent state.
Example of a btmon trace when this happened:
< HCI Command: Inquiry Cancel (0x01|0x0002) plen 0
> HCI Event: Inquiry Complete (0x01) plen 1
Status: Success (0x00)
> HCI Event: Command Complete (0x0e) plen 4
Inquiry Cancel (0x01|0x0002) ncmd 1
Status: Command Disallowed (0x0c)
Signed-off-by: Sonny Sasaka <sonnysasaka@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 05942b8c36 ]
The USB phy takes some time to reset, so make sure we give it to it. The
delay length was taken from the 4x12 phy driver.
This manifested in issues with the DWC2 driver since commit fe369e1826
("usb: dwc2: Make dwc2_readl/writel functions endianness-agnostic.")
where the endianness check would read the DWC ID as 0 due to the phy still
resetting, resulting in the wrong endian mode being chosen.
Signed-off-by: Jonathan Bakker <xc-racer2@live.ca>
Link: https://lore.kernel.org/r/BN6PR04MB06605D52502816E500683553A3D10@BN6PR04MB0660.namprd04.prod.outlook.com
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 266150c94c ]
Realloc of size zero is a free not an error, avoid this causing a double
free. Caught by clang's address sanitizer:
==2634==ERROR: AddressSanitizer: attempting double-free on 0x6020000015f0 in thread T0:
#0 0x5649659297fd in free llvm/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:123:3
#1 0x5649659e9251 in __zfree tools/lib/zalloc.c:13:2
#2 0x564965c0f92c in mem2node__exit tools/perf/util/mem2node.c:114:2
#3 0x564965a08b4c in perf_c2c__report tools/perf/builtin-c2c.c:2867:2
#4 0x564965a0616a in cmd_c2c tools/perf/builtin-c2c.c:2989:10
#5 0x564965944348 in run_builtin tools/perf/perf.c:312:11
#6 0x564965943235 in handle_internal_command tools/perf/perf.c:364:8
#7 0x5649659440c4 in run_argv tools/perf/perf.c:408:2
#8 0x564965942e41 in main tools/perf/perf.c:538:3
0x6020000015f0 is located 0 bytes inside of 1-byte region [0x6020000015f0,0x6020000015f1)
freed by thread T0 here:
#0 0x564965929da3 in realloc third_party/llvm/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:164:3
#1 0x564965c0f55e in mem2node__init tools/perf/util/mem2node.c:97:16
#2 0x564965a08956 in perf_c2c__report tools/perf/builtin-c2c.c:2803:8
#3 0x564965a0616a in cmd_c2c tools/perf/builtin-c2c.c:2989:10
#4 0x564965944348 in run_builtin tools/perf/perf.c:312:11
#5 0x564965943235 in handle_internal_command tools/perf/perf.c:364:8
#6 0x5649659440c4 in run_argv tools/perf/perf.c:408:2
#7 0x564965942e41 in main tools/perf/perf.c:538:3
previously allocated by thread T0 here:
#0 0x564965929c42 in calloc third_party/llvm/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:154:3
#1 0x5649659e9220 in zalloc tools/lib/zalloc.c:8:9
#2 0x564965c0f32d in mem2node__init tools/perf/util/mem2node.c:61:12
#3 0x564965a08956 in perf_c2c__report tools/perf/builtin-c2c.c:2803:8
#4 0x564965a0616a in cmd_c2c tools/perf/builtin-c2c.c:2989:10
#5 0x564965944348 in run_builtin tools/perf/perf.c:312:11
#6 0x564965943235 in handle_internal_command tools/perf/perf.c:364:8
#7 0x5649659440c4 in run_argv tools/perf/perf.c:408:2
#8 0x564965942e41 in main tools/perf/perf.c:538:3
v2: add a WARN_ON_ONCE when the free condition arises.
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: clang-built-linux@googlegroups.com
Link: http://lore.kernel.org/lkml/20200320182347.87675-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 98448cdfe7 ]
We don't need to be quite as strict about mismatched AArch32 support,
which is good because the friendly hardware folks have been busy
mismatching this to their hearts' content.
* We don't care about EL2 or EL3 (there are silly comments concerning
the latter, so remove those)
* EL1 support is gated by the ARM64_HAS_32BIT_EL1 capability and handled
gracefully when a mismatch occurs
* EL0 support is gated by the ARM64_HAS_32BIT_EL0 capability and handled
gracefully when a mismatch occurs
Relax the AArch32 checks to FTR_NONSTRICT.
Tested-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20200421142922.18950-8-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 44b8fb6eaa ]
After registering character device the file operation callbacks can be
called. The open callback registers interrupt handler.
Therefore interrupt handler can execute in parallel with rest of the init
function. To avoid such data race initialize telclk_interrupt variable
and struct alarm_events before registering character device.
Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Link: https://lore.kernel.org/r/20200417153451.1551-1-madhuparnabhowmik10@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b849dd84b6 ]
While trying to "dd" to the block device for a USB stick, I
encountered a hung task warning (blocked for > 120 seconds). I
managed to come up with an easy way to reproduce this on my system
(where /dev/sdb is the block device for my USB stick) with:
while true; do dd if=/dev/zero of=/dev/sdb bs=4M; done
With my reproduction here are the relevant bits from the hung task
detector:
INFO: task udevd:294 blocked for more than 122 seconds.
...
udevd D 0 294 1 0x00400008
Call trace:
...
mutex_lock_nested+0x40/0x50
__blkdev_get+0x7c/0x3d4
blkdev_get+0x118/0x138
blkdev_open+0x94/0xa8
do_dentry_open+0x268/0x3a0
vfs_open+0x34/0x40
path_openat+0x39c/0xdf4
do_filp_open+0x90/0x10c
do_sys_open+0x150/0x3c8
...
...
Showing all locks held in the system:
...
1 lock held by dd/2798:
#0: ffffff814ac1a3b8 (&bdev->bd_mutex){+.+.}, at: __blkdev_put+0x50/0x204
...
dd D 0 2798 2764 0x00400208
Call trace:
...
schedule+0x8c/0xbc
io_schedule+0x1c/0x40
wait_on_page_bit_common+0x238/0x338
__lock_page+0x5c/0x68
write_cache_pages+0x194/0x500
generic_writepages+0x64/0xa4
blkdev_writepages+0x24/0x30
do_writepages+0x48/0xa8
__filemap_fdatawrite_range+0xac/0xd8
filemap_write_and_wait+0x30/0x84
__blkdev_put+0x88/0x204
blkdev_put+0xc4/0xe4
blkdev_close+0x28/0x38
__fput+0xe0/0x238
____fput+0x1c/0x28
task_work_run+0xb0/0xe4
do_notify_resume+0xfc0/0x14bc
work_pending+0x8/0x14
The problem appears related to the fact that my USB disk is terribly
slow and that I have a lot of RAM in my system to cache things.
Specifically my writes seem to be happening at ~15 MB/s and I've got
~4 GB of RAM in my system that can be used for buffering. To write 4
GB of buffer to disk thus takes ~4000 MB / ~15 MB/s = ~267 seconds.
The 267 second number is a problem because in __blkdev_put() we call
sync_blockdev() while holding the bd_mutex. Any other callers who
want the bd_mutex will be blocked for the whole time.
The problem is made worse because I believe blkdev_put() specifically
tells other tasks (namely udev) to go try to access the device at right
around the same time we're going to hold the mutex for a long time.
Putting some traces around this (after disabling the hung task detector),
I could confirm:
dd: 437.608600: __blkdev_put() right before sync_blockdev() for sdb
udevd: 437.623901: blkdev_open() right before blkdev_get() for sdb
dd: 661.468451: __blkdev_put() right after sync_blockdev() for sdb
udevd: 663.820426: blkdev_open() right after blkdev_get() for sdb
A simple fix for this is to realize that sync_blockdev() works fine if
you're not holding the mutex. Also, it's not the end of the world if
you sync a little early (though it can have performance impacts).
Thus we can make a guess that we're going to need to do the sync and
then do it without holding the mutex. We still do one last sync with
the mutex but it should be much, much faster.
With this, my hung task warnings for my test case are gone.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7289fdb5dc ]
Fixes a NULL pointer dereference, caused by the PIT firing an interrupt
before the interrupt table has been initialized.
SET_PIT2 can race with the creation of the IRQchip. In particular,
if SET_PIT2 is called with a low PIT timer period (after the creation of
the IOAPIC, but before the instantiation of the irq routes), the PIT can
fire an interrupt at an uninitialized table.
Signed-off-by: Steve Rutherford <srutherford@google.com>
Signed-off-by: Jon Cargille <jcargill@google.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Message-Id: <20200416191152.259434-1-jcargill@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 09ef5283fd ]
On passing requirement to vm_unmapped_area, arch_get_unmapped_area and
arch_get_unmapped_area_topdown did not set align_offset. Internally on
both unmapped_area and unmapped_area_topdown, if info->align_mask is 0,
then info->align_offset was meaningless.
But commit df529cabb7 ("mm: mmap: add trace point of
vm_unmapped_area") always prints info->align_offset even though it is
uninitialized.
Fix this uninitialized value issue by setting it to 0 explicitly.
Before:
vm_unmapped_area: addr=0x755b155000 err=0 total_vm=0x15aaf0 flags=0x1 len=0x109000 lo=0x8000 hi=0x75eed48000 mask=0x0 ofs=0x4022
After:
vm_unmapped_area: addr=0x74a4ca1000 err=0 total_vm=0x168ab1 flags=0x1 len=0x9000 lo=0x8000 hi=0x753d94b000 mask=0x0 ofs=0x0
Signed-off-by: Jaewon Kim <jaewon31.kim@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michel Lespinasse <walken@google.com>
Cc: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/20200409094035.19457-1-jaewon31.kim@samsung.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 21f9024355 ]
In case rdma accept fails at nvmet_rdma_queue_connect(), release work is
scheduled. Later on, a new RDMA CM event may arrive since we didn't
destroy the cm-id and call nvmet_rdma_queue_connect_fail(), which
schedule another release work. This will cause calling
nvmet_rdma_free_queue twice. To fix this we implicitly destroy the cm_id
with non-zero ret code, which guarantees that new rdma_cm events will
not arrive afterwards. Also add a qp pointer to nvmet_rdma_queue
structure, so we can use it when the cm_id pointer is NULL or was
destroyed.
Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Suggested-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 5644e1fbbf ]
pgdat->kswapd_classzone_idx could be accessed concurrently in
wakeup_kswapd(). Plain writes and reads without any lock protection
result in data races. Fix them by adding a pair of READ|WRITE_ONCE() as
well as saving a branch (compilers might well optimize the original code
in an unintentional way anyway). While at it, also take care of
pgdat->kswapd_order and non-kswapd threads in allow_direct_reclaim(). The
data races were reported by KCSAN,
BUG: KCSAN: data-race in wakeup_kswapd / wakeup_kswapd
write to 0xffff9f427ffff2dc of 4 bytes by task 7454 on cpu 13:
wakeup_kswapd+0xf1/0x400
wakeup_kswapd at mm/vmscan.c:3967
wake_all_kswapds+0x59/0xc0
wake_all_kswapds at mm/page_alloc.c:4241
__alloc_pages_slowpath+0xdcc/0x1290
__alloc_pages_slowpath at mm/page_alloc.c:4512
__alloc_pages_nodemask+0x3bb/0x450
alloc_pages_vma+0x8a/0x2c0
do_anonymous_page+0x16e/0x6f0
__handle_mm_fault+0xcd5/0xd40
handle_mm_fault+0xfc/0x2f0
do_page_fault+0x263/0x6f9
page_fault+0x34/0x40
1 lock held by mtest01/7454:
#0: ffff9f425afe8808 (&mm->mmap_sem#2){++++}, at:
do_page_fault+0x143/0x6f9
do_user_addr_fault at arch/x86/mm/fault.c:1405
(inlined by) do_page_fault at arch/x86/mm/fault.c:1539
irq event stamp: 6944085
count_memcg_event_mm+0x1a6/0x270
count_memcg_event_mm+0x119/0x270
__do_softirq+0x34c/0x57c
irq_exit+0xa2/0xc0
read to 0xffff9f427ffff2dc of 4 bytes by task 7472 on cpu 38:
wakeup_kswapd+0xc8/0x400
wake_all_kswapds+0x59/0xc0
__alloc_pages_slowpath+0xdcc/0x1290
__alloc_pages_nodemask+0x3bb/0x450
alloc_pages_vma+0x8a/0x2c0
do_anonymous_page+0x16e/0x6f0
__handle_mm_fault+0xcd5/0xd40
handle_mm_fault+0xfc/0x2f0
do_page_fault+0x263/0x6f9
page_fault+0x34/0x40
1 lock held by mtest01/7472:
#0: ffff9f425a9ac148 (&mm->mmap_sem#2){++++}, at:
do_page_fault+0x143/0x6f9
irq event stamp: 6793561
count_memcg_event_mm+0x1a6/0x270
count_memcg_event_mm+0x119/0x270
__do_softirq+0x34c/0x57c
irq_exit+0xa2/0xc0
BUG: KCSAN: data-race in kswapd / wakeup_kswapd
write to 0xffff90973ffff2dc of 4 bytes by task 820 on cpu 6:
kswapd+0x27c/0x8d0
kthread+0x1e0/0x200
ret_from_fork+0x27/0x50
read to 0xffff90973ffff2dc of 4 bytes by task 6299 on cpu 0:
wakeup_kswapd+0xf3/0x450
wake_all_kswapds+0x59/0xc0
__alloc_pages_slowpath+0xdcc/0x1290
__alloc_pages_nodemask+0x3bb/0x450
alloc_pages_vma+0x8a/0x2c0
do_anonymous_page+0x170/0x700
__handle_mm_fault+0xc9f/0xd00
handle_mm_fault+0xfc/0x2f0
do_page_fault+0x263/0x6f9
page_fault+0x34/0x40
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Marco Elver <elver@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Link: http://lkml.kernel.org/r/1582749472-5171-1-git-send-email-cai@lca.pw
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit faffdfa04f ]
Mount failure issue happens under the scenario: Application forked dozens
of threads to mount the same number of cramfs images separately in docker,
but several mounts failed with high probability. Mount failed due to the
checking result of the page(read from the superblock of loop dev) is not
uptodate after wait_on_page_locked(page) returned in function cramfs_read:
wait_on_page_locked(page);
if (!PageUptodate(page)) {
...
}
The reason of the checking result of the page not uptodate: systemd-udevd
read the loopX dev before mount, because the status of loopX is Lo_unbound
at this time, so loop_make_request directly trigger the calling of io_end
handler end_buffer_async_read, which called SetPageError(page). So It
caused the page can't be set to uptodate in function
end_buffer_async_read:
if(page_uptodate && !PageError(page)) {
SetPageUptodate(page);
}
Then mount operation is performed, it used the same page which is just
accessed by systemd-udevd above, Because this page is not uptodate, it
will launch a actual read via submit_bh, then wait on this page by calling
wait_on_page_locked(page). When the I/O of the page done, io_end handler
end_buffer_async_read is called, because no one cleared the page
error(during the whole read path of mount), which is caused by
systemd-udevd reading, so this page is still in "PageError" status, which
can't be set to uptodate in function end_buffer_async_read, then caused
mount failure.
But sometimes mount succeed even through systemd-udeved read loopX dev
just before, The reason is systemd-udevd launched other loopX read just
between step 3.1 and 3.2, the steps as below:
1, loopX dev default status is Lo_unbound;
2, systemd-udved read loopX dev (page is set to PageError);
3, mount operation
1) set loopX status to Lo_bound;
==>systemd-udevd read loopX dev<==
2) read loopX dev(page has no error)
3) mount succeed
As the loopX dev status is set to Lo_bound after step 3.1, so the other
loopX dev read by systemd-udevd will go through the whole I/O stack, part
of the call trace as below:
SYS_read
vfs_read
do_sync_read
blkdev_aio_read
generic_file_aio_read
do_generic_file_read:
ClearPageError(page);
mapping->a_ops->readpage(filp, page);
here, mapping->a_ops->readpage() is blkdev_readpage. In latest kernel,
some function name changed, the call trace as below:
blkdev_read_iter
generic_file_read_iter
generic_file_buffered_read:
/*
* A previous I/O error may have been due to temporary
* failures, eg. mutipath errors.
* Pg_error will be set again if readpage fails.
*/
ClearPageError(page);
/* Start the actual read. The read will unlock the page*/
error=mapping->a_ops->readpage(flip, page);
We can see ClearPageError(page) is called before the actual read,
then the read in step 3.2 succeed.
This patch is to add the calling of ClearPageError just before the actual
read of read path of cramfs mount. Without the patch, the call trace as
below when performing cramfs mount:
do_mount
cramfs_read
cramfs_blkdev_read
read_cache_page
do_read_cache_page:
filler(data, page);
or
mapping->a_ops->readpage(data, page);
With the patch, the call trace as below when performing mount:
do_mount
cramfs_read
cramfs_blkdev_read
read_cache_page:
do_read_cache_page:
ClearPageError(page); <== new add
filler(data, page);
or
mapping->a_ops->readpage(data, page);
With the patch, mount operation trigger the calling of
ClearPageError(page) before the actual read, the page has no error if no
additional page error happen when I/O done.
Signed-off-by: Xianting Tian <xianting_tian@126.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Jan Kara <jack@suse.cz>
Cc: <yubin@h3c.com>
Link: http://lkml.kernel.org/r/1583318844-22971-1-git-send-email-xianting_tian@126.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b0d14fc43d ]
Clang warns:
mm/kmemleak.c:1955:28: warning: array comparison always evaluates to a constant [-Wtautological-compare]
if (__start_ro_after_init < _sdata || __end_ro_after_init > _edata)
^
mm/kmemleak.c:1955:60: warning: array comparison always evaluates to a constant [-Wtautological-compare]
if (__start_ro_after_init < _sdata || __end_ro_after_init > _edata)
These are not true arrays, they are linker defined symbols, which are just
addresses. Using the address of operator silences the warning and does
not change the resulting assembly with either clang/ld.lld or gcc/ld
(tested with diff + objdump -Dr).
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://github.com/ClangBuiltLinux/linux/issues/895
Link: http://lkml.kernel.org/r/20200220051551.44000-1-natechancellor@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 08ca8b21f7 ]
When a subrequest is being detached from the subgroup, we want to
ensure that it is not holding the group lock, or in the process
of waiting for the group lock.
Fixes: 5b2b5187fa ("NFS: Fix nfs_page_group_destroy() and nfs_lock_and_join_requests() race cases")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
