[ Upstream commit c749d9b7ebbc5716af7a95f7768634b30d9446ec ]
generic/077 on x86_32 CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP=y with highmem,
on huge=always tmpfs, issues a warning and then hangs (interruptibly):
WARNING: CPU: 5 PID: 3517 at mm/highmem.c:622 kunmap_local_indexed+0x62/0xc9
CPU: 5 UID: 0 PID: 3517 Comm: cp Not tainted 6.12.0-rc4 #2
...
copy_page_from_iter_atomic+0xa6/0x5ec
generic_perform_write+0xf6/0x1b4
shmem_file_write_iter+0x54/0x67
Fix copy_page_from_iter_atomic() by limiting it in that case
(include/linux/skbuff.h skb_frag_must_loop() does similar).
But going forward, perhaps CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP is too
surprising, has outlived its usefulness, and should just be removed?
Fixes: 908a1ad894 ("iov_iter: Handle compound highmem pages in copy_page_from_iter_atomic()")
Signed-off-by: Hugh Dickins <hughd@google.com>
Link: https://lore.kernel.org/r/dd5f0c89-186e-18e1-4f43-19a60f5a9774@google.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9c70b2a33cd2aa6a5a59c5523ef053bd42265209 ]
When running stress-ng-vm-segv test, we found a null pointer dereference
error in task_numa_work(). Here is the backtrace:
[323676.066985] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020
......
[323676.067108] CPU: 35 PID: 2694524 Comm: stress-ng-vm-se
......
[323676.067113] pstate: 23401009 (nzCv daif +PAN -UAO +TCO +DIT +SSBS BTYPE=--)
[323676.067115] pc : vma_migratable+0x1c/0xd0
[323676.067122] lr : task_numa_work+0x1ec/0x4e0
[323676.067127] sp : ffff8000ada73d20
[323676.067128] x29: ffff8000ada73d20 x28: 0000000000000000 x27: 000000003e89f010
[323676.067130] x26: 0000000000080000 x25: ffff800081b5c0d8 x24: ffff800081b27000
[323676.067133] x23: 0000000000010000 x22: 0000000104d18cc0 x21: ffff0009f7158000
[323676.067135] x20: 0000000000000000 x19: 0000000000000000 x18: ffff8000ada73db8
[323676.067138] x17: 0001400000000000 x16: ffff800080df40b0 x15: 0000000000000035
[323676.067140] x14: ffff8000ada73cc8 x13: 1fffe0017cc72001 x12: ffff8000ada73cc8
[323676.067142] x11: ffff80008001160c x10: ffff000be639000c x9 : ffff8000800f4ba4
[323676.067145] x8 : ffff000810375000 x7 : ffff8000ada73974 x6 : 0000000000000001
[323676.067147] x5 : 0068000b33e26707 x4 : 0000000000000001 x3 : ffff0009f7158000
[323676.067149] x2 : 0000000000000041 x1 : 0000000000004400 x0 : 0000000000000000
[323676.067152] Call trace:
[323676.067153] vma_migratable+0x1c/0xd0
[323676.067155] task_numa_work+0x1ec/0x4e0
[323676.067157] task_work_run+0x78/0xd8
[323676.067161] do_notify_resume+0x1ec/0x290
[323676.067163] el0_svc+0x150/0x160
[323676.067167] el0t_64_sync_handler+0xf8/0x128
[323676.067170] el0t_64_sync+0x17c/0x180
[323676.067173] Code: d2888001 910003fd f9000bf3 aa0003f3 (f9401000)
[323676.067177] SMP: stopping secondary CPUs
[323676.070184] Starting crashdump kernel...
stress-ng-vm-segv in stress-ng is used to stress test the SIGSEGV error
handling function of the system, which tries to cause a SIGSEGV error on
return from unmapping the whole address space of the child process.
Normally this program will not cause kernel crashes. But before the
munmap system call returns to user mode, a potential task_numa_work()
for numa balancing could be added and executed. In this scenario, since the
child process has no vma after munmap, the vma_next() in task_numa_work()
will return a null pointer even if the vma iterator restarts from 0.
Recheck the vma pointer before dereferencing it in task_numa_work().
Fixes: 214dbc4281 ("sched: convert to vma iterator")
Signed-off-by: Shawn Wang <shawnwang@linux.alibaba.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org # v6.2+
Link: https://lkml.kernel.org/r/20241025022208.125527-1-shawnwang@linux.alibaba.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3d6ebf16438de5d712030fefbb4182b46373d677 ]
It turns out since its original introduction, pre-2.6.12,
bus_rescan_devices() has skipped devices that might be in the process of
attaching or detaching from their driver. For CXL this behavior is
unwanted and expects that cxl_bus_rescan() is a probe barrier.
That behavior is simple enough to achieve with bus_for_each_dev() paired
with call to device_attach(), and it is unclear why bus_rescan_devices()
took the position of lockless consumption of dev->driver which is racy.
The "Fixes:" but no "Cc: stable" on this patch reflects that the issue
is merely by inspection since the bug that triggered the discovery of
this potential problem [1] is fixed by other means. However, a stable
backport should do no harm.
Fixes: 8dd2bc0f8e ("cxl/mem: Add the cxl_mem driver")
Link: http://lore.kernel.org/20241004212504.1246-1-gourry@gourry.net [1]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Gregory Price <gourry@gourry.net>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Link: https://patch.msgid.link/172964781104.81806.4277549800082443769.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit bffdf9d7e51a7be8eeaac2ccf9e54a5fde01ff65 ]
The driver neglects to free the instance of I2C regmap constructed at
the beginning of the edt_ft5x06_ts_probe() method when probe fails.
Additionally edt_ft5x06_ts_remove() is freeing the regmap too early,
before the rest of the device resources that are managed by devm are
released.
Fix this by installing a custom devm action that will ensure that the
regmap is released at the right time during normal teardown as well as
in case of probe failure.
Note that devm_regmap_init_i2c() could not be used because the driver
may replace the original regmap with a regmap specific for M06 devices
in the middle of the probe, and using devm_regmap_init_i2c() would
result in releasing the M06 regmap too early.
Reported-by: Li Zetao <lizetao1@huawei.com>
Fixes: 9dfd9708ff ("Input: edt-ft5x06 - convert to use regmap API")
Cc: stable@vger.kernel.org
Reviewed-by: Oliver Graute <oliver.graute@kococonnector.com>
Link: https://lore.kernel.org/r/ZxL6rIlVlgsAu-Jv@google.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f89263b69731e0144d275fff777ee0dd92069200 ]
When enable initcall_debug together with higher debug level below.
CONFIG_CONSOLE_LOGLEVEL_DEFAULT=9
CONFIG_CONSOLE_LOGLEVEL_QUIET=9
CONFIG_MESSAGE_LOGLEVEL_DEFAULT=7
The initialization of i.MX8MP PCIe PHY might be timeout failed randomly.
To fix this issue, adjust the sequence of the resets refer to the power
up sequence listed below.
i.MX8MP PCIe PHY power up sequence:
/---------------------------------------------
1.8v supply ---------/
/---------------------------------------------------
0.8v supply ---/
---\ /--------------------------------------------------
X REFCLK Valid
Reference Clock ---/ \--------------------------------------------------
-------------------------------------------
|
i_init_restn --------------
------------------------------------
|
i_cmn_rstn ---------------------
-------------------------------
|
o_pll_lock_done --------------------------
Logs:
imx6q-pcie 33800000.pcie: host bridge /soc@0/pcie@33800000 ranges:
imx6q-pcie 33800000.pcie: IO 0x001ff80000..0x001ff8ffff -> 0x0000000000
imx6q-pcie 33800000.pcie: MEM 0x0018000000..0x001fefffff -> 0x0018000000
probe of clk_imx8mp_audiomix.reset.0 returned 0 after 1052 usecs
probe of 30e20000.clock-controller returned 0 after 32971 usecs
phy phy-32f00000.pcie-phy.4: phy poweron failed --> -110
probe of 30e10000.dma-controller returned 0 after 10235 usecs
imx6q-pcie 33800000.pcie: waiting for PHY ready timeout!
dwhdmi-imx 32fd8000.hdmi: Detected HDMI TX controller v2.13a with HDCP (samsung_dw_hdmi_phy2)
imx6q-pcie 33800000.pcie: probe with driver imx6q-pcie failed with error -110
Fixes: dce9edff16 ("phy: freescale: imx8m-pcie: Add i.MX8MP PCIe PHY support")
Cc: stable@vger.kernel.org
Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
v2 changes:
- Rebase to latest fixes branch of linux-phy git repo.
- Richard's environment have problem and can't sent out patch. So I help
post this fix patch.
Link: https://lore.kernel.org/r/20241021155241.943665-1-Frank.Li@nxp.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 117932eea99b729ee5d12783601a4f7f5fd58a23 ]
A hung_task problem shown below was found:
INFO: task kworker/0:0:8 blocked for more than 327 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Workqueue: events cgroup_bpf_release
Call Trace:
<TASK>
__schedule+0x5a2/0x2050
? find_held_lock+0x33/0x100
? wq_worker_sleeping+0x9e/0xe0
schedule+0x9f/0x180
schedule_preempt_disabled+0x25/0x50
__mutex_lock+0x512/0x740
? cgroup_bpf_release+0x1e/0x4d0
? cgroup_bpf_release+0xcf/0x4d0
? process_scheduled_works+0x161/0x8a0
? cgroup_bpf_release+0x1e/0x4d0
? mutex_lock_nested+0x2b/0x40
? __pfx_delay_tsc+0x10/0x10
mutex_lock_nested+0x2b/0x40
cgroup_bpf_release+0xcf/0x4d0
? process_scheduled_works+0x161/0x8a0
? trace_event_raw_event_workqueue_execute_start+0x64/0xd0
? process_scheduled_works+0x161/0x8a0
process_scheduled_works+0x23a/0x8a0
worker_thread+0x231/0x5b0
? __pfx_worker_thread+0x10/0x10
kthread+0x14d/0x1c0
? __pfx_kthread+0x10/0x10
ret_from_fork+0x59/0x70
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1b/0x30
</TASK>
This issue can be reproduced by the following pressuse test:
1. A large number of cpuset cgroups are deleted.
2. Set cpu on and off repeatly.
3. Set watchdog_thresh repeatly.
The scripts can be obtained at LINK mentioned above the signature.
The reason for this issue is cgroup_mutex and cpu_hotplug_lock are
acquired in different tasks, which may lead to deadlock.
It can lead to a deadlock through the following steps:
1. A large number of cpusets are deleted asynchronously, which puts a
large number of cgroup_bpf_release works into system_wq. The max_active
of system_wq is WQ_DFL_ACTIVE(256). Consequently, all active works are
cgroup_bpf_release works, and many cgroup_bpf_release works will be put
into inactive queue. As illustrated in the diagram, there are 256 (in
the acvtive queue) + n (in the inactive queue) works.
2. Setting watchdog_thresh will hold cpu_hotplug_lock.read and put
smp_call_on_cpu work into system_wq. However step 1 has already filled
system_wq, 'sscs.work' is put into inactive queue. 'sscs.work' has
to wait until the works that were put into the inacvtive queue earlier
have executed (n cgroup_bpf_release), so it will be blocked for a while.
3. Cpu offline requires cpu_hotplug_lock.write, which is blocked by step 2.
4. Cpusets that were deleted at step 1 put cgroup_release works into
cgroup_destroy_wq. They are competing to get cgroup_mutex all the time.
When cgroup_metux is acqured by work at css_killed_work_fn, it will
call cpuset_css_offline, which needs to acqure cpu_hotplug_lock.read.
However, cpuset_css_offline will be blocked for step 3.
5. At this moment, there are 256 works in active queue that are
cgroup_bpf_release, they are attempting to acquire cgroup_mutex, and as
a result, all of them are blocked. Consequently, sscs.work can not be
executed. Ultimately, this situation leads to four processes being
blocked, forming a deadlock.
system_wq(step1) WatchDog(step2) cpu offline(step3) cgroup_destroy_wq(step4)
...
2000+ cgroups deleted asyn
256 actives + n inactives
__lockup_detector_reconfigure
P(cpu_hotplug_lock.read)
put sscs.work into system_wq
256 + n + 1(sscs.work)
sscs.work wait to be executed
warting sscs.work finish
percpu_down_write
P(cpu_hotplug_lock.write)
...blocking...
css_killed_work_fn
P(cgroup_mutex)
cpuset_css_offline
P(cpu_hotplug_lock.read)
...blocking...
256 cgroup_bpf_release
mutex_lock(&cgroup_mutex);
..blocking...
To fix the problem, place cgroup_bpf_release works on a dedicated
workqueue which can break the loop and solve the problem. System wqs are
for misc things which shouldn't create a large number of concurrent work
items. If something is going to generate >WQ_DFL_ACTIVE(256) concurrent
work items, it should use its own dedicated workqueue.
Fixes: 4bfc0bb2c6 ("bpf: decouple the lifetime of cgroup_bpf from cgroup itself")
Cc: stable@vger.kernel.org # v5.3+
Link: https://lore.kernel.org/cgroups/e90c32d2-2a85-4f28-9154-09c7d320cb60@huawei.com/T/#t
Tested-by: Vishal Chourasia <vishalc@linux.ibm.com>
Signed-off-by: Chen Ridong <chenridong@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2ff949441802a8d076d9013c7761f63e8ae5a9bd ]
blk_rq_map_user_bvec contains a check bytes + bv->bv_len > nr_iter which
causes unnecessary failures in NVMe passthrough I/O, reproducible as
follows:
- register a 2 page, page-aligned buffer against a ring
- use that buffer to do a 1 page io_uring NVMe passthrough read
The second (i = 1) iteration of the loop in blk_rq_map_user_bvec will
then have nr_iter == 1 page, bytes == 1 page, bv->bv_len == 1 page, so
the check bytes + bv->bv_len > nr_iter will succeed, causing the I/O to
fail. This failure is unnecessary, as when the check succeeds, it means
we've checked the entire buffer that will be used by the request - i.e.
blk_rq_map_user_bvec should complete successfully. Therefore, terminate
the loop early and return successfully when the check bytes + bv->bv_len
> nr_iter succeeds.
While we're at it, also remove the check that all segments in the bvec
are single-page. While this seems to be true for all users of the
function, it doesn't appear to be required anywhere downstream.
CC: stable@vger.kernel.org
Signed-off-by: Xinyu Zhang <xizhang@purestorage.com>
Co-developed-by: Uday Shankar <ushankar@purestorage.com>
Signed-off-by: Uday Shankar <ushankar@purestorage.com>
Fixes: 3798754793 ("block: extend functionality to map bvec iterator")
Link: https://lore.kernel.org/r/20241023211519.4177873-1-ushankar@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 8c68b5656e55e9324875881f1000eb4ee3603a87 upstream.
On sdhci_gl9767_set_clock(), the vendor header space(VHS) is read-only
after calling gl9767_disable_ssc_pll() and gl9767_set_ssc_pll_205mhz().
So the low power negotiation mode cannot be enabled again.
Introduce gl9767_set_low_power_negotiation() function to fix it.
The explanation process is as below.
static void sdhci_gl9767_set_clock()
{
...
gl9767_vhs_write();
...
value |= PCIE_GLI_9767_CFG_LOW_PWR_OFF;
pci_write_config_dword(pdev, PCIE_GLI_9767_CFG, value); <--- (a)
gl9767_disable_ssc_pll(); <--- (b)
sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
if (clock == 0)
return; <-- (I)
...
if (clock == 200000000 && ios->timing == MMC_TIMING_UHS_SDR104) {
...
gl9767_set_ssc_pll_205mhz(); <--- (c)
}
...
value &= ~PCIE_GLI_9767_CFG_LOW_PWR_OFF;
pci_write_config_dword(pdev, PCIE_GLI_9767_CFG, value); <-- (II)
gl9767_vhs_read();
}
(a) disable low power negotiation mode. When return on (I), the low power
mode is disabled. After (b) and (c), VHS is read-only, the low power mode
cannot be enabled on (II).
Reported-by: Georg Gottleuber <ggo@tuxedocomputers.com>
Fixes: d275435551 ("mmc: sdhci-pci-gli: Set SDR104's clock to 205MHz and enable SSC for GL9767")
Signed-off-by: Ben Chuang <ben.chuang@genesyslogic.com.tw>
Tested-by: Georg Gottleuber <ggo@tuxedocomputers.com>
Cc: stable@vger.kernel.org
Message-ID: <20241025060017.1663697-1-benchuanggli@gmail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 101c268bd2f37e965a5468353e62d154db38838e upstream.
In support of investigating an initialization failure report [1],
cxl_test was updated to register mock memory-devices after the mock
root-port/bus device had been registered. That led to cxl_test crashing
with a use-after-free bug with the following signature:
cxl_port_attach_region: cxl region3: cxl_host_bridge.0:port3 decoder3.0 add: mem0:decoder7.0 @ 0 next: cxl_switch_uport.0 nr_eps: 1 nr_targets: 1
cxl_port_attach_region: cxl region3: cxl_host_bridge.0:port3 decoder3.0 add: mem4:decoder14.0 @ 1 next: cxl_switch_uport.0 nr_eps: 2 nr_targets: 1
cxl_port_setup_targets: cxl region3: cxl_switch_uport.0:port6 target[0] = cxl_switch_dport.0 for mem0:decoder7.0 @ 0
1) cxl_port_setup_targets: cxl region3: cxl_switch_uport.0:port6 target[1] = cxl_switch_dport.4 for mem4:decoder14.0 @ 1
[..]
cxld_unregister: cxl decoder14.0:
cxl_region_decode_reset: cxl_region region3:
mock_decoder_reset: cxl_port port3: decoder3.0 reset
2) mock_decoder_reset: cxl_port port3: decoder3.0: out of order reset, expected decoder3.1
cxl_endpoint_decoder_release: cxl decoder14.0:
[..]
cxld_unregister: cxl decoder7.0:
3) cxl_region_decode_reset: cxl_region region3:
Oops: general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6bc3: 0000 [#1] PREEMPT SMP PTI
[..]
RIP: 0010:to_cxl_port+0x8/0x60 [cxl_core]
[..]
Call Trace:
<TASK>
cxl_region_decode_reset+0x69/0x190 [cxl_core]
cxl_region_detach+0xe8/0x210 [cxl_core]
cxl_decoder_kill_region+0x27/0x40 [cxl_core]
cxld_unregister+0x5d/0x60 [cxl_core]
At 1) a region has been established with 2 endpoint decoders (7.0 and
14.0). Those endpoints share a common switch-decoder in the topology
(3.0). At teardown, 2), decoder14.0 is the first to be removed and hits
the "out of order reset case" in the switch decoder. The effect though
is that region3 cleanup is aborted leaving it in-tact and
referencing decoder14.0. At 3) the second attempt to teardown region3
trips over the stale decoder14.0 object which has long since been
deleted.
The fix here is to recognize that the CXL specification places no
mandate on in-order shutdown of switch-decoders, the driver enforces
in-order allocation, and hardware enforces in-order commit. So, rather
than fail and leave objects dangling, always remove them.
In support of making cxl_region_decode_reset() always succeed,
cxl_region_invalidate_memregion() failures are turned into warnings.
Crashing the kernel is ok there since system integrity is at risk if
caches cannot be managed around physical address mutation events like
CXL region destruction.
A new device_for_each_child_reverse_from() is added to cleanup
port->commit_end after all dependent decoders have been disabled. In
other words if decoders are allocated 0->1->2 and disabled 1->2->0 then
port->commit_end only decrements from 2 after 2 has been disabled, and
it decrements all the way to zero since 1 was disabled previously.
Link: http://lore.kernel.org/20241004212504.1246-1-gourry@gourry.net [1]
Cc: stable@vger.kernel.org
Fixes: 176baefb2e ("cxl/hdm: Commit decoder state to hardware")
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Alison Schofield <alison.schofield@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Zijun Hu <quic_zijuhu@quicinc.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Link: https://patch.msgid.link/172964782781.81806.17902885593105284330.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3cea8af2d1a9ae5869b47c3dabe3b20f331f3bbd upstream.
Currently, when configuring TMU (Time Management Unit) mode of a given
router, we take into account only its own TMU requirements ignoring
other routers in the domain. This is problematic if the router we are
configuring has lower TMU requirements than what is already configured
in the domain.
In the scenario below, we have a host router with two USB4 ports: A and
B. Port A connected to device router #1 (which supports CL states) and
existing DisplayPort tunnel, thus, the TMU mode is HiFi uni-directional.
1. Initial topology
[Host]
A/
/
[Device #1]
/
Monitor
2. Plug in device #2 (that supports CL states) to downstream port B of
the host router
[Host]
A/ B\
/ \
[Device #1] [Device #2]
/
Monitor
The TMU mode on port B and port A will be configured to LowRes which is
not what we want and will cause monitor to start flickering.
To address this we first scan the domain and search for any router
configured to HiFi uni-directional mode, and if found, configure TMU
mode of the given router to HiFi uni-directional as well.
Cc: stable@vger.kernel.org
Signed-off-by: Gil Fine <gil.fine@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ece5897e5a10fcd56a317e32f2dc7219f366a5a8 upstream.
Commit e6d2c436ff ("tools/mm: allow users to provide additional
cflags/ldflags") passes now CFLAGS to Makefile. With this, build systems
with default -Werror enabled found:
slabinfo.c:1300:25: error: ignoring return value of 'chdir'
declared with attribute 'warn_unused_result' [-Werror=unused-result]
chdir("..");
^~~~~~~~~~~
page-types.c:397:35: error: format '%lu' expects argument of type
'long unsigned int', but argument 2 has type 'uint64_t'
{aka 'long long unsigned int'} [-Werror=format=]
printf("%lu\t", mapcnt0);
~~^ ~~~~~~~
..
Fix page-types by using PRIu64 for uint64_t prints and check in slabinfo
for return code on chdir("..").
Link: https://lkml.kernel.org/r/c1ceb507-94bc-461c-934d-c19b77edd825@gmail.com
Fixes: e6d2c436ff ("tools/mm: allow users to provide additional cflags/ldflags")
Signed-off-by: Wladislav Wiebe <wladislav.kw@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Herton R. Krzesinski <herton@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d949d1d14fa281ace388b1de978e8f2cd52875cf upstream.
I got the following KCSAN report during syzbot testing:
==================================================================
BUG: KCSAN: data-race in generic_fillattr / inode_set_ctime_current
write to 0xffff888102eb3260 of 4 bytes by task 6565 on cpu 1:
inode_set_ctime_to_ts include/linux/fs.h:1638 [inline]
inode_set_ctime_current+0x169/0x1d0 fs/inode.c:2626
shmem_mknod+0x117/0x180 mm/shmem.c:3443
shmem_create+0x34/0x40 mm/shmem.c:3497
lookup_open fs/namei.c:3578 [inline]
open_last_lookups fs/namei.c:3647 [inline]
path_openat+0xdbc/0x1f00 fs/namei.c:3883
do_filp_open+0xf7/0x200 fs/namei.c:3913
do_sys_openat2+0xab/0x120 fs/open.c:1416
do_sys_open fs/open.c:1431 [inline]
__do_sys_openat fs/open.c:1447 [inline]
__se_sys_openat fs/open.c:1442 [inline]
__x64_sys_openat+0xf3/0x120 fs/open.c:1442
x64_sys_call+0x1025/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:258
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x54/0x120 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
read to 0xffff888102eb3260 of 4 bytes by task 3498 on cpu 0:
inode_get_ctime_nsec include/linux/fs.h:1623 [inline]
inode_get_ctime include/linux/fs.h:1629 [inline]
generic_fillattr+0x1dd/0x2f0 fs/stat.c:62
shmem_getattr+0x17b/0x200 mm/shmem.c:1157
vfs_getattr_nosec fs/stat.c:166 [inline]
vfs_getattr+0x19b/0x1e0 fs/stat.c:207
vfs_statx_path fs/stat.c:251 [inline]
vfs_statx+0x134/0x2f0 fs/stat.c:315
vfs_fstatat+0xec/0x110 fs/stat.c:341
__do_sys_newfstatat fs/stat.c:505 [inline]
__se_sys_newfstatat+0x58/0x260 fs/stat.c:499
__x64_sys_newfstatat+0x55/0x70 fs/stat.c:499
x64_sys_call+0x141f/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:263
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x54/0x120 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
value changed: 0x2755ae53 -> 0x27ee44d3
Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3498 Comm: udevd Not tainted 6.11.0-rc6-syzkaller-00326-gd1f2d51b711a-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
==================================================================
When calling generic_fillattr(), if you don't hold read lock, data-race
will occur in inode member variables, which can cause unexpected
behavior.
Since there is no special protection when shmem_getattr() calls
generic_fillattr(), data-race occurs by functions such as shmem_unlink()
or shmem_mknod(). This can cause unexpected results, so commenting it out
is not enough.
Therefore, when calling generic_fillattr() from shmem_getattr(), it is
appropriate to protect the inode using inode_lock_shared() and
inode_unlock_shared() to prevent data-race.
Link: https://lkml.kernel.org/r/20240909123558.70229-1-aha310510@gmail.com
Fixes: 44a30220bc ("shmem: recalculate file inode when fstat")
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
Reported-by: syzbot <syzkaller@googlegroup.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1966db682f064172891275cb951aa8c98a0a809b upstream.
When SVPBMT is enabled, __acpi_map_table() will directly access the
data in DDR through the IO attribute, rather than through hardware
cache consistency, resulting in incorrect data in the obtained ACPI
table.
The log: ACPI: [ACPI:0x18] Invalid zero length.
We do not assume whether the bootloader flushes or not. We should
access in a cacheable way instead of maintaining cache consistency
by software.
Fixes: 3b426d4b5b ("RISC-V: ACPI : Fix for usage of pointers in different address space")
Cc: stable@vger.kernel.org
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: Yunhui Cui <cuiyunhui@bytedance.com>
Reviewed-by: Sunil V L <sunilvl@ventanamicro.com>
Link: https://lore.kernel.org/r/20241014130141.86426-1-cuiyunhui@bytedance.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b3a033e3ecd3471248d474ef263aadc0059e516a upstream.
Syzbot reported that page_symlink(), called by nilfs_symlink(), triggers
memory reclamation involving the filesystem layer, which can result in
circular lock dependencies among the reader/writer semaphore
nilfs->ns_segctor_sem, s_writers percpu_rwsem (intwrite) and the
fs_reclaim pseudo lock.
This is because after commit 21fc61c73c ("don't put symlink bodies in
pagecache into highmem"), the gfp flags of the page cache for symbolic
links are overwritten to GFP_KERNEL via inode_nohighmem().
This is not a problem for symlinks read from the backing device, because
the __GFP_FS flag is dropped after inode_nohighmem() is called. However,
when a new symlink is created with nilfs_symlink(), the gfp flags remain
overwritten to GFP_KERNEL. Then, memory allocation called from
page_symlink() etc. triggers memory reclamation including the FS layer,
which may call nilfs_evict_inode() or nilfs_dirty_inode(). And these can
cause a deadlock if they are called while nilfs->ns_segctor_sem is held:
Fix this issue by dropping the __GFP_FS flag from the page cache GFP flags
of newly created symlinks in the same way that nilfs_new_inode() and
__nilfs_read_inode() do, as a workaround until we adopt nofs allocation
scope consistently or improve the locking constraints.
Link: https://lkml.kernel.org/r/20241020050003.4308-1-konishi.ryusuke@gmail.com
Fixes: 21fc61c73c ("don't put symlink bodies in pagecache into highmem")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+9ef37ac20608f4836256@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=9ef37ac20608f4836256
Tested-by: syzbot+9ef37ac20608f4836256@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 63dd163cd61dda6f38343776b42331cc6b7e56e0 upstream.
The raw value conversion to obtain a measurement in lux as
INT_PLUS_MICRO does not calculate the decimal part properly to display
it as micro (in this case microlux). It only calculates the module to
obtain the decimal part from a resolution that is 10000 times the
provided in the datasheet (0.5376 lux/cnt for the veml6030). The
resulting value must still be multiplied by 100 to make it micro.
This bug was introduced with the original implementation of the driver.
Only the illuminance channel is fixed becuase the scale is non sensical
for the intensity channels anyway.
Cc: stable@vger.kernel.org
Fixes: 7b779f573c ("iio: light: add driver for veml6030 ambient light sensor")
Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
Link: https://patch.msgid.link/20241016-veml6030-fix-processed-micro-v1-1-4a5644796437@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit efa353ae1b0541981bc96dbf2e586387d0392baa upstream.
In the ad7124_write_raw() function, parameter val can potentially
be zero. This may lead to a division by zero when DIV_ROUND_CLOSEST()
is called within ad7124_set_channel_odr(). The ad7124_write_raw()
function is invoked through the sequence: iio_write_channel_raw() ->
iio_write_channel_attribute() -> iio_channel_write(), with no checks
in place to ensure val is non-zero.
Cc: stable@vger.kernel.org
Fixes: 7b8d045e49 ("iio: adc: ad7124: allow more than 8 channels")
Signed-off-by: Zicheng Qu <quzicheng@huawei.com>
Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Link: https://patch.msgid.link/20241022134330.574601-1-quzicheng@huawei.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e15d84b3bba187aa372dff7c58ce1fd5cb48a076 upstream.
In the current logic, memory is allocated for storing the MSDU context
during management packet TX but this memory is not being freed during
management TX completion. Similar leaks are seen in the management TX
cleanup logic.
Kmemleak reports this problem as below,
unreferenced object 0xffffff80b64ed250 (size 16):
comm "kworker/u16:7", pid 148, jiffies 4294687130 (age 714.199s)
hex dump (first 16 bytes):
00 2b d8 d8 80 ff ff ff c4 74 e9 fd 07 00 00 00 .+.......t......
backtrace:
[<ffffffe6e7b245dc>] __kmem_cache_alloc_node+0x1e4/0x2d8
[<ffffffe6e7adde88>] kmalloc_trace+0x48/0x110
[<ffffffe6bbd765fc>] ath10k_wmi_tlv_op_gen_mgmt_tx_send+0xd4/0x1d8 [ath10k_core]
[<ffffffe6bbd3eed4>] ath10k_mgmt_over_wmi_tx_work+0x134/0x298 [ath10k_core]
[<ffffffe6e78d5974>] process_scheduled_works+0x1ac/0x400
[<ffffffe6e78d60b8>] worker_thread+0x208/0x328
[<ffffffe6e78dc890>] kthread+0x100/0x1c0
[<ffffffe6e78166c0>] ret_from_fork+0x10/0x20
Free the memory during completion and cleanup to fix the leak.
Protect the mgmt_pending_tx idr_remove() operation in
ath10k_wmi_tlv_op_cleanup_mgmt_tx_send() using ar->data_lock similar to
other instances.
Tested-on: WCN3990 hw1.0 SNOC WLAN.HL.2.0-01387-QCAHLSWMTPLZ-1
Fixes: dc405152bb ("ath10k: handle mgmt tx completion event")
Fixes: c730c47717 ("ath10k: Remove msdu from idr when management pkt send fails")
Cc: stable@vger.kernel.org
Signed-off-by: Manikanta Pubbisetty <quic_mpubbise@quicinc.com>
Link: https://patch.msgid.link/20241015064103.6060-1-quic_mpubbise@quicinc.com
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5bb1f4c9340e01003b00b94d539eadb0da88f48e upstream.
Patch series "selftests/mm: revert pthread_barrier change"
On Android arm, pthread_create followed by a fork caused a deadlock in
the case where the fork required work to be completed by the created
thread.
The previous patches incorrectly assumed that the parent would
always initialize the pthread_barrier for the child thread. This
reverts the change and replaces the fix for wp-fork-with-event with the
original use of atomic_bool.
This patch (of 3):
This reverts commit e142cc87ac4ec618f2ccf5f68aedcd6e28a59d9d.
fork_event_consumer may be called by other tests that do not initialize
the pthread_barrier, so this approach is not correct. The subsequent
patch will revert to using atomic_bool instead.
Link: https://lkml.kernel.org/r/20241018171734.2315053-1-edliaw@google.com
Link: https://lkml.kernel.org/r/20241018171734.2315053-2-edliaw@google.com
Fixes: e142cc87ac4e ("fix deadlock for fork after pthread_create on ARM")
Signed-off-by: Edward Liaw <edliaw@google.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 31004740e42846a6f0bb255e6348281df3eb8032 upstream.
Use pm_runtime_put in the remove function and pm_runtime_get to disable
RPM on platforms that don't support runtime D3, as re-enabling it through
sysfs auto power control may cause the controller to malfunction. This
can lead to issues such as hotplug devices not being detected due to
failed interrupt generation.
Fixes: a5d6264b638e ("xhci: Enable RPM on controllers that support low-power states")
Cc: stable <stable@kernel.org>
Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Link: https://lore.kernel.org/r/20241024133718.723846-1-Basavaraj.Natikar@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 075919f6df5dd82ad0b1894898b315fbb3c29b84 upstream.
During the aborting of a command, the software receives a command
completion event for the command ring stopped, with the TRB pointing
to the next TRB after the aborted command.
If the command we abort is located just before the Link TRB in the
command ring, then during the 'command ring stopped' completion event,
the xHC gives the Link TRB in the event's cmd DMA, which causes a
mismatch in handling command completion event.
To address this situation, move the 'command ring stopped' completion
event check slightly earlier, since the specific command it stopped
on isn't of significant concern.
Fixes: 7f84eef0da ("USB: xhci: No-op command queueing and irq handler.")
Cc: stable@vger.kernel.org
Signed-off-by: Faisal Hassan <quic_faisalh@quicinc.com>
Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20241022155631.1185-1-quic_faisalh@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 29240130ab77c80bea1464317ae2a5fd29c16a0c upstream.
Commit 413db06c05 ("phy: qcom-qmp-usb: clean up probe initialisation")
removed most users of the platform device driver data from the
qcom-qmp-usb driver, but mistakenly also removed the initialisation
despite the data still being used in the runtime PM callbacks. This bug
was later reproduced when the driver was copied to create the
qmp-usb-legacy driver.
Restore the driver data initialisation at probe to avoid a NULL-pointer
dereference on runtime suspend.
Apparently no one uses runtime PM, which currently needs to be enabled
manually through sysfs, with these drivers.
Fixes: e464a3180a ("phy: qcom-qmp-usb: split off the legacy USB+dp_com support")
Cc: stable@vger.kernel.org # 6.6
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20240911115253.10920-3-johan+linaro@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bd9e4d4a3b127686efc60096271b0a44c3100061 upstream.
Commit 413db06c05 ("phy: qcom-qmp-usb: clean up probe initialisation")
removed most users of the platform device driver data, but mistakenly
also removed the initialisation despite the data still being used in the
runtime PM callbacks.
Restore the driver data initialisation at probe to avoid a NULL-pointer
dereference on runtime suspend.
Apparently no one uses runtime PM, which currently needs to be enabled
manually through sysfs, with this driver.
Fixes: 413db06c05 ("phy: qcom-qmp-usb: clean up probe initialisation")
Cc: stable@vger.kernel.org # 6.2
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20240911115253.10920-2-johan+linaro@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fdce49b5da6e0fb6d077986dec3e90ef2b094b50 upstream.
For devm_usb_put_phy(), its comment says it needs to invoke usb_put_phy()
to release the phy, but it does not do that actually, so it can not fully
undo what the API devm_usb_get_phy() does, that is wrong, fixed by using
devres_release() instead of devres_destroy() within the API.
Fixes: cedf860237 ("usb: phy: move bulk of otg/otg.c to phy/phy.c")
Cc: stable@vger.kernel.org
Signed-off-by: Zijun Hu <quic_zijuhu@quicinc.com>
Link: https://lore.kernel.org/r/20241020-usb_phy_fix-v1-1-7f79243b8e1e@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4413665dd6c528b31284119e3571c25f371e1c36 upstream.
The WD19 family of docks has the same audio chipset as the WD15. This
change enables jack detection on the WD19.
We don't need the dell_dock_mixer_init quirk for the WD19. It is only
needed because of the dell_alc4020_map quirk for the WD15 in
mixer_maps.c, which disables the volume controls. Even for the WD15,
this quirk was apparently only needed when the dock firmware was not
updated.
Signed-off-by: Jan Schär <jan@jschaer.ch>
Cc: <stable@vger.kernel.org>
Link: https://patch.msgid.link/20241029221249.15661-1-jan@jschaer.ch
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit fd70e9f1d85f5323096ad313ba73f5fe3d15ea41 ]
For kernels built with CONFIG_FORCE_NR_CPUS=y, the nr_cpu_ids is
defined as NR_CPUS instead of the number of possible cpus, this
will cause the following system panic:
smpboot: Allowing 4 CPUs, 0 hotplug CPUs
...
setup_percpu: NR_CPUS:512 nr_cpumask_bits:512 nr_cpu_ids:512 nr_node_ids:1
...
BUG: unable to handle page fault for address: ffffffff9911c8c8
Oops: 0000 [#1] PREEMPT SMP PTI
CPU: 0 PID: 15 Comm: rcu_tasks_trace Tainted: G W
6.6.21 #1 5dc7acf91a5e8e9ac9dcfc35bee0245691283ea6
RIP: 0010:rcu_tasks_need_gpcb+0x25d/0x2c0
RSP: 0018:ffffa371c00a3e60 EFLAGS: 00010082
CR2: ffffffff9911c8c8 CR3: 000000040fa20005 CR4: 00000000001706f0
Call Trace:
<TASK>
? __die+0x23/0x80
? page_fault_oops+0xa4/0x180
? exc_page_fault+0x152/0x180
? asm_exc_page_fault+0x26/0x40
? rcu_tasks_need_gpcb+0x25d/0x2c0
? __pfx_rcu_tasks_kthread+0x40/0x40
rcu_tasks_one_gp+0x69/0x180
rcu_tasks_kthread+0x94/0xc0
kthread+0xe8/0x140
? __pfx_kthread+0x40/0x40
ret_from_fork+0x34/0x80
? __pfx_kthread+0x40/0x40
ret_from_fork_asm+0x1b/0x80
</TASK>
Considering that there may be holes in the CPU numbers, use the
maximum possible cpu number, instead of nr_cpu_ids, for configuring
enqueue and dequeue limits.
[ neeraj.upadhyay: Fix htmldocs build error reported by Stephen Rothwell ]
Closes: https://lore.kernel.org/linux-input/CALMA0xaTSMN+p4xUXkzrtR5r6k7hgoswcaXx7baR_z9r5jjskw@mail.gmail.com/T/#u
Reported-by: Zhixu Liu <zhixu.liu@gmail.com>
Signed-off-by: Zqiang <qiang.zhang1211@gmail.com>
Signed-off-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 46faf9d8e1d52e4a91c382c6c72da6bd8e68297b ]
Holding a mutex across synchronize_rcu_tasks() and acquiring
that same mutex in code called from do_exit() after its call to
exit_tasks_rcu_start() but before its call to exit_tasks_rcu_stop()
results in deadlock. This is by design, because tasks that are far
enough into do_exit() are no longer present on the tasks list, making
it a bit difficult for RCU Tasks to find them, let alone wait on them
to do a voluntary context switch. However, such deadlocks are becoming
more frequent. In addition, lockdep currently does not detect such
deadlocks and they can be difficult to reproduce.
In addition, if a task voluntarily context switches during that time
(for example, if it blocks acquiring a mutex), then this task is in an
RCU Tasks quiescent state. And with some adjustments, RCU Tasks could
just as well take advantage of that fact.
This commit therefore initializes the data structures that will be needed
to rely on these quiescent states and to eliminate these deadlocks.
Link: https://lore.kernel.org/all/20240118021842.290665-1-chenzhongjin@huawei.com/
Reported-by: Chen Zhongjin <chenzhongjin@huawei.com>
Reported-by: Yang Jihong <yangjihong1@huawei.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Tested-by: Yang Jihong <yangjihong1@huawei.com>
Tested-by: Chen Zhongjin <chenzhongjin@huawei.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Stable-dep-of: fd70e9f1d85f ("rcu-tasks: Fix access non-existent percpu rtpcp variable in rcu_tasks_need_gpcb()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit bfe93930ea1ea3c6c115a7d44af6e4fea609067e ]
Holding a mutex across synchronize_rcu_tasks() and acquiring
that same mutex in code called from do_exit() after its call to
exit_tasks_rcu_start() but before its call to exit_tasks_rcu_stop()
results in deadlock. This is by design, because tasks that are far
enough into do_exit() are no longer present on the tasks list, making
it a bit difficult for RCU Tasks to find them, let alone wait on them
to do a voluntary context switch. However, such deadlocks are becoming
more frequent. In addition, lockdep currently does not detect such
deadlocks and they can be difficult to reproduce.
In addition, if a task voluntarily context switches during that time
(for example, if it blocks acquiring a mutex), then this task is in an
RCU Tasks quiescent state. And with some adjustments, RCU Tasks could
just as well take advantage of that fact.
This commit therefore adds the data structures that will be needed
to rely on these quiescent states and to eliminate these deadlocks.
Link: https://lore.kernel.org/all/20240118021842.290665-1-chenzhongjin@huawei.com/
Reported-by: Chen Zhongjin <chenzhongjin@huawei.com>
Reported-by: Yang Jihong <yangjihong1@huawei.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Tested-by: Yang Jihong <yangjihong1@huawei.com>
Tested-by: Chen Zhongjin <chenzhongjin@huawei.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Stable-dep-of: fd70e9f1d85f ("rcu-tasks: Fix access non-existent percpu rtpcp variable in rcu_tasks_need_gpcb()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e62d8ae4620865411d1b2347980aa28ccf891a3d ]
The rcu_tasks_need_gpcb() samples ->percpu_dequeue_lim as part of the
condition clause of a "for" loop, which is a bit confusing. This commit
therefore hoists this sampling out of the loop, using the result loaded
in the condition clause.
So why does this work in the face of a concurrent switch from single-CPU
queueing to per-CPU queueing?
o The call_rcu_tasks_generic() that makes the change has already
enqueued its callback, which means that all of the other CPU's
callback queues are empty.
o For the call_rcu_tasks_generic() that first notices
the switch to per-CPU queues, the smp_store_release()
used to update ->percpu_enqueue_lim pairs with the
raw_spin_trylock_rcu_node()'s full barrier that is
between the READ_ONCE(rtp->percpu_enqueue_shift) and the
rcu_segcblist_enqueue() that enqueues the callback.
o Because this CPU's queue is empty (unless it happens to
be the original single queue, in which case there is no
need for synchronization), this call_rcu_tasks_generic()
will do an irq_work_queue() to schedule a handler for the
needed rcuwait_wake_up() call. This call will be ordered
after the first call_rcu_tasks_generic() function's change to
->percpu_dequeue_lim.
o This rcuwait_wake_up() will either happen before or after the
set_current_state() in rcuwait_wait_event(). If it happens
before, the "condition" argument's call to rcu_tasks_need_gpcb()
will be ordered after the original change, and all callbacks on
all CPUs will be visible. Otherwise, if it happens after, then
the grace-period kthread's state will be set back to running,
which will result in a later call to rcuwait_wait_event() and
thus to rcu_tasks_need_gpcb(), which will again see the change.
So it all works out.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Stable-dep-of: fd70e9f1d85f ("rcu-tasks: Fix access non-existent percpu rtpcp variable in rcu_tasks_need_gpcb()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 5189df7b8088268012882c220d6aca4e64981348 ]
The syzbot fuzzer has been encountering "task hung" problems ever
since the dummy-hcd driver was changed to use hrtimers instead of
regular timers. It turns out that the problems are caused by a subtle
difference between the timer_pending() and hrtimer_active() APIs.
The changeover blindly replaced the first by the second. However,
timer_pending() returns True when the timer is queued but not when its
callback is running, whereas hrtimer_active() returns True when the
hrtimer is queued _or_ its callback is running. This difference
occasionally caused dummy_urb_enqueue() to think that the callback
routine had not yet started when in fact it was almost finished. As a
result the hrtimer was not restarted, which made it impossible for the
driver to dequeue later the URB that was just enqueued. This caused
usb_kill_urb() to hang, and things got worse from there.
Since hrtimers have no API for telling when they are queued and the
callback isn't running, the driver must keep track of this for itself.
That's what this patch does, adding a new "timer_pending" flag and
setting or clearing it at the appropriate times.
Reported-by: syzbot+f342ea16c9d06d80b585@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-usb/6709234e.050a0220.3e960.0011.GAE@google.com/
Tested-by: syzbot+f342ea16c9d06d80b585@syzkaller.appspotmail.com
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Fixes: a7f3813e589f ("usb: gadget: dummy_hcd: Switch to hrtimer transfer scheduler")
Cc: Marcello Sylvester Bauer <sylv@sylv.io>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/2dab644e-ef87-4de8-ac9a-26f100b2c609@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
