[ Upstream commit 755915fc28 ]
For a 75 Byte request, it would send the first 64 separately, then detect
that the remaining 11 Byte fit into a single DMA, but due to this bug set
the length to the original 75 Bytes. This leads to a DMA failure (which is
ignored...) and the request completes without the remaining bytes having
been sent.
Fixes: b84a8dee23 ("usb: gadget: add Faraday fotg210_udc driver")
Signed-off-by: Fabian Vogt <fabian@ritter-vogt.de>
Link: https://lore.kernel.org/r/20210324141115.9384-2-fabian@ritter-vogt.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8609f5cfdc ]
ADF_STATUS_PF_RUNNING is (only) used and checked by adf_vf2pf_shutdown()
before calling adf_iov_putmsg()->mutex_lock(vf2pf_lock), however the
vf2pf_lock is initialized in adf_dev_init(), which can fail and when it
fail, the vf2pf_lock is either not initialized or destroyed, a subsequent
use of vf2pf_lock will cause issue.
To fix this issue, only set this flag if adf_dev_init() returns 0.
[ 7.178404] BUG: KASAN: user-memory-access in __mutex_lock.isra.0+0x1ac/0x7c0
[ 7.180345] Call Trace:
[ 7.182576] mutex_lock+0xc9/0xd0
[ 7.183257] adf_iov_putmsg+0x118/0x1a0 [intel_qat]
[ 7.183541] adf_vf2pf_shutdown+0x4d/0x7b [intel_qat]
[ 7.183834] adf_dev_shutdown+0x172/0x2b0 [intel_qat]
[ 7.184127] adf_probe+0x5e9/0x600 [qat_dh895xccvf]
Signed-off-by: Tong Zhang <ztong0001@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Fixes: 25c6ffb249 ("crypto: qat - check if PF is running")
Acked-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit fbdbbe6d3e ]
Since we have a separate routine for VBUS sense, the interrupt may occur
before gadget driver is present. Hence, ->setup() call may oops the kernel:
[ 55.245843] BUG: kernel NULL pointer dereference, address: 00000010
...
[ 55.245843] EIP: pch_udc_isr.cold+0x162/0x33f
...
[ 55.245843] <IRQ>
[ 55.245843] ? pch_udc_svc_data_out+0x160/0x160
Check if driver is present before calling ->setup().
Fixes: f646cf9452 ("USB device driver of Topcliff PCH")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210323153626.54908-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7189b3c119 ]
Currently, the late microcode loading mechanism checks whether any CPUs
are offlined, and, in such a case, aborts the load attempt.
However, this must be done before the kernel caches new microcode from
the filesystem. Otherwise, when offlined CPUs are onlined later, those
cores are going to be updated through the CPU hotplug notifier callback
with the new microcode, while CPUs previously onine will continue to run
with the older microcode.
For example:
Turn off one core (2 threads):
echo 0 > /sys/devices/system/cpu/cpu3/online
echo 0 > /sys/devices/system/cpu/cpu1/online
Install the ucode fails because a primary SMT thread is offline:
cp intel-ucode/06-8e-09 /lib/firmware/intel-ucode/
echo 1 > /sys/devices/system/cpu/microcode/reload
bash: echo: write error: Invalid argument
Turn the core back on
echo 1 > /sys/devices/system/cpu/cpu3/online
echo 1 > /sys/devices/system/cpu/cpu1/online
cat /proc/cpuinfo |grep microcode
microcode : 0x30
microcode : 0xde
microcode : 0x30
microcode : 0xde
The rationale for why the update is aborted when at least one primary
thread is offline is because even if that thread is soft-offlined
and idle, it will still have to participate in broadcasted MCE's
synchronization dance or enter SMM, and in both examples it will execute
instructions so it better have the same microcode revision as the other
cores.
[ bp: Heavily edit and extend commit message with the reasoning behind all
this. ]
Fixes: 30ec26da99 ("x86/microcode: Do not upload microcode if CPUs are offline")
Signed-off-by: Otavio Pontes <otavio.pontes@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Acked-by: Ashok Raj <ashok.raj@intel.com>
Link: https://lkml.kernel.org/r/20210319165515.9240-2-otavio.pontes@intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 55fbb9ba4f ]
In qcom_probe_nand_devices() function, the error code returned by
qcom_nand_host_init_and_register() is converted to -ENODEV in the case
of failure. This poses issue if -EPROBE_DEFER is returned when the
dependency is not available for a component like parser.
So let's restructure the error handling logic a bit and return the
actual error code in case of qcom_nand_host_init_and_register() failure.
Fixes: c76b78d8ec ("mtd: nand: Qualcomm NAND controller driver")
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 08608adb52 ]
There are chances that the parse_mtd_partitions() function will return
-EPROBE_DEFER in mtd_device_parse_register(). This might happen when
the dependency is not available for the parser. For instance, on SDX55
the MTD_QCOMSMEM_PARTS parser depends on the QCOM_SMEM driver to parse
the partitions defined in the shared memory region. With the current
flow, the error returned from parse_mtd_partitions() will be discarded
in favor of trying to add the fallback partition.
This will prevent the driver to end up in probe deferred pool and the
partitions won't be parsed even after the QCOM_SMEM driver is available.
Fix this issue by bailing out of mtd_device_parse_register() when
-EPROBE_DEFER error is returned from parse_mtd_partitions() function and
propagate the error code to the driver core for probing later.
Fixes: 5ac67ce36c ("mtd: move code adding (registering) partitions to the parse_mtd_partitions()")
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f5200c1424 ]
Hamming ECC doesn't cover the OOB data, so reading or writing OOB shall
always be done without ECC enabled.
This is a problem when adding JFFS2 cleanmarkers to erased blocks. If JFFS2
clenmarkers are added to the OOB with ECC enabled, OOB bytes will be changed
from ff ff ff to 00 00 00, reporting incorrect ECC errors.
Fixes: 27c5b17cd1 ("mtd: nand: add NAND driver "library" for Broadcom STB NAND controller")
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20210224080210.23686-1-noltari@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e41a962f82 ]
There is a upstream commit cffa4b2122f5("regmap:debugfs:
Fix a memory leak when calling regmap_attach_dev") that
adds a if condition when create name for debugfs_name.
With below function invoking logical, debugfs_name is
freed in regmap_debugfs_exit(), but it is not created again
because of the if condition introduced by above commit.
regmap_reinit_cache()
regmap_debugfs_exit()
...
regmap_debugfs_init()
So, set debugfs_name to NULL after it is freed.
Fixes: cffa4b2122 ("regmap: debugfs: Fix a memory leak when calling regmap_attach_dev")
Signed-off-by: Meng Li <Meng.Li@windriver.com>
Link: https://lore.kernel.org/r/20210226021737.7690-1-Meng.Li@windriver.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 19c234a14e ]
While interpreting CC_STATUS, ROLE_CONTROL has to be read to make
sure that CC1/CC2 is not forced presenting Rp/Rd.
>From the TCPCI spec:
4.4.5.2 ROLE_CONTROL (Normative):
The TCPM shall write B6 (DRP) = 0b and B3..0 (CC1/CC2) if it wishes
to control the Rp/Rd directly instead of having the TCPC perform
DRP toggling autonomously. When controlling Rp/Rd directly, the
TCPM writes to B3..0 (CC1/CC2) each time it wishes to change the
CC1/CC2 values. This control is used for TCPM-TCPC implementing
Source or Sink only as well as when a connection has been detected
via DRP toggling but the TCPM wishes to attempt Try.Src or Try.Snk.
Table 4-22. CC_STATUS Register Definition:
If (ROLE_CONTROL.CC1 = Rd) or ConnectResult=1)
00b: SNK.Open (Below maximum vRa)
01b: SNK.Default (Above minimum vRd-Connect)
10b: SNK.Power1.5 (Above minimum vRd-Connect) Detects Rp-1.5A
11b: SNK.Power3.0 (Above minimum vRd-Connect) Detects Rp-3.0A
If (ROLE_CONTROL.CC2=Rd) or (ConnectResult=1)
00b: SNK.Open (Below maximum vRa)
01b: SNK.Default (Above minimum vRd-Connect)
10b: SNK.Power1.5 (Above minimum vRd-Connect) Detects Rp 1.5A
11b: SNK.Power3.0 (Above minimum vRd-Connect) Detects Rp 3.0A
Fixes: 74e656d6b0 ("staging: typec: Type-C Port Controller Interface driver (tcpci)")
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Badhri Jagan Sridharan <badhri@google.com>
Link: https://lore.kernel.org/r/20210304070931.1947316-1-badhri@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3db1d52466 ]
In "tx_empty", we should poll TC bit in both DMA and PIO modes (instead of
TXE) to check transmission data register has been transmitted independently
of the FIFO mode. TC indicates that both transmit register and shift
register are empty. When shift register is empty, tx_empty should return
TIOCSER_TEMT instead of TC value.
Cleans the USART_CR_TC TCCF register define (transmission complete clear
flag) as it is duplicate of USART_ICR_TCCF.
Fixes: 48a6092fb4 ("serial: stm32-usart: Add STM32 USART Driver")
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20210304162308.8984-13-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f264c6f6ae ]
Incorrect characters are observed on console during boot. This issue occurs
when init/main.c is modifying termios settings to open /dev/console on the
rootfs.
This patch adds a waiting loop in set_termios to wait for TX shift register
empty (and TX FIFO if any) before stopping serial port.
Fixes: 48a6092fb4 ("serial: stm32-usart: Add STM32 USART Driver")
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20210304162308.8984-4-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8987efbb17 ]
The Maxim PMIC datasheets describe the interrupt line as active low
with a requirement of acknowledge from the CPU. Without specifying the
interrupt type in Devicetree, kernel might apply some fixed
configuration, not necessarily working for this hardware.
Additionally, the interrupt line is shared so using level sensitive
interrupt is here especially important to avoid races.
Fixes: c61248afa8 ("ARM: dts: Add max77686 RTC interrupt to cros5250-common")
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20201210212534.216197-9-krzk@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f6368c6056 ]
The Maxim PMIC datasheets describe the interrupt line as active low
with a requirement of acknowledge from the CPU. Without specifying the
interrupt type in Devicetree, kernel might apply some fixed
configuration, not necessarily working for this hardware.
Additionally, the interrupt line is shared so using level sensitive
interrupt is here especially important to avoid races.
Fixes: 47580e8d94 ("ARM: dts: Specify MAX77686 pmic interrupt for exynos5250-smdk5250")
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20201210212534.216197-8-krzk@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 6503c568e9 ]
The Maxim PMIC datasheets describe the interrupt line as active low
with a requirement of acknowledge from the CPU. Without specifying the
interrupt type in Devicetree, kernel might apply some fixed
configuration, not necessarily working for this hardware.
Additionally, the interrupt line is shared so using level sensitive
interrupt is here especially important to avoid races.
Fixes: eea6653aae ("ARM: dts: Enable PMIC interrupts for exynos4412-odroid-common")
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20201210212534.216197-6-krzk@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e52dcd6e70 ]
The Maxim PMIC datasheets describe the interrupt line as active low
with a requirement of acknowledge from the CPU. Without specifying the
interrupt type in Devicetree, kernel might apply some fixed
configuration, not necessarily working for this hardware.
Additionally, the interrupt line is shared so using level sensitive
interrupt is here especially important to avoid races.
Fixes: 15dfdfad2d ("ARM: dts: Add basic dts for Exynos4412-based Trats 2 board")
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20201210212534.216197-5-krzk@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 15107e443a ]
The Maxim MUIC datasheets describe the interrupt line as active low
with a requirement of acknowledge from the CPU. Without specifying the
interrupt type in Devicetree, kernel might apply some fixed
configuration, not necessarily working for this hardware.
Additionally, the interrupt line is shared so using level sensitive
interrupt is here especially important to avoid races.
Fixes: 7eec126675 ("ARM: dts: Add Maxim 77693 PMIC to exynos4412-trats2")
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20201210212534.216197-4-krzk@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8a45f33bd3 ]
The Maxim fuel gauge datasheets describe the interrupt line as active
low with a requirement of acknowledge from the CPU. The falling edge
interrupt will mostly work but it's not correct.
Fixes: e8614292cd ("ARM: dts: Add Maxim 77693 fuel gauge node for exynos4412-trats2")
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20201210212534.216197-3-krzk@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e004c3e67b ]
Currently the array gpmc_cs is indexed by cs before it cs is range checked
and the pointer read from this out-of-index read is dereferenced. Fix this
by performing the range check on cs before the read and the following
pointer dereference.
Addresses-Coverity: ("Negative array index read")
Fixes: 9ed7a776eb ("ARM: OMAP2+: Fix support for multiple devices on a GPMC chip select")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20210223193821.17232-1-colin.king@canonical.com
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 50a318cc9b upstream.
The commit d3cb25a121 ("usb: gadget: udc: fix spin_lock in pch_udc")
obviously was not thought through and had made the situation even worse
than it was before. Two changes after almost reverted it. but a few
leftovers have been left as it. With this revert d3cb25a121 completely.
While at it, narrow down the scope of unlocked section to prevent
potential race when prot_stall is assigned.
Fixes: d3cb25a121 ("usb: gadget: udc: fix spin_lock in pch_udc")
Fixes: 9903b6bedd ("usb: gadget: pch-udc: fix lock")
Fixes: 1d23d16a88 ("usb: gadget: pch_udc: reorder spin_[un]lock to avoid deadlock")
Cc: Iago Abal <mail@iagoabal.eu>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210323153626.54908-5-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7b279bbfd2 upstream.
Smatch complains about missing that the ovl_override_creds() doesn't
have a matching revert_creds() if the dentry is disconnected. Fix this
by moving the ovl_override_creds() until after the disconnected check.
Fixes: aa3ff3c152 ("ovl: copy up of disconnected dentries")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 44bada2821 upstream.
store_regs_fmt2() has an ordering problem: first the guarded storage
facility is enabled on the local cpu, then preemption disabled, and
then the STGSC (store guarded storage controls) instruction is
executed.
If the process gets scheduled away between enabling the guarded
storage facility and before preemption is disabled, this might lead to
a special operation exception and therefore kernel crash as soon as
the process is scheduled back and the STGSC instruction is executed.
Fixes: 4e0b1ab72b ("KVM: s390: gs support for kvm guests")
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Cc: <stable@vger.kernel.org> # 4.12
Link: https://lore.kernel.org/r/20210415080127.1061275-1-hca@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b6b4fbd90b upstream.
Initialize MSR_TSC_AUX with CPU node information if RDTSCP or RDPID is
supported. This fixes a bug where vdso_read_cpunode() will read garbage
via RDPID if RDPID is supported but RDTSCP is not. While no known CPU
supports RDPID but not RDTSCP, both Intel's SDM and AMD's APM allow for
RDPID to exist without RDTSCP, e.g. it's technically a legal CPU model
for a virtual machine.
Note, technically MSR_TSC_AUX could be initialized if and only if RDPID
is supported since RDTSCP is currently not used to retrieve the CPU node.
But, the cost of the superfluous WRMSR is negigible, whereas leaving
MSR_TSC_AUX uninitialized is just asking for future breakage if someone
decides to utilize RDTSCP.
Fixes: a582c540ac ("x86/vdso: Use RDPID in preference to LSL when available")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210504225632.1532621-2-seanjc@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit defce244b0 upstream.
The quirk entry for Uniwill ECS M31EI is with the PCI SSID device 0,
which means matching with all. That is, it's essentially equivalent
with SND_PCI_QUIRK_VENDOR(0x1584), which also matches with the
previous entry for Haier W18 applying the very same quirk.
Let's unify them with the single vendor-quirk entry.
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210428112704.23967-13-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 45461e3b55 upstream.
Just re-order the alc269_fixup_tbl[] entries for HP devices for
avoiding the oversight of the duplicated or unapplied item in future.
No functional changes.
Formerly, some entries were grouped for the actual codec, but this
doesn't seem reasonable to keep in that way. So now we simply keep
the PCI SSID order for the whole.
Also Cc-to-stable for the further patch applications.
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210428112704.23967-5-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8dbc2ccac5 upstream.
Currently the ioctl command RADEON_INFO_SI_BACKEND_ENABLED_MASK can
copy back uninitialised data in value_tmp that pointer *value points
to. This can occur when rdev->family is less than CHIP_BONAIRE and
less than CHIP_TAHITI. Fix this by adding in a missing -EINVAL
so that no invalid value is copied back to userspace.
Addresses-Coverity: ("Uninitialized scalar variable)
Cc: stable@vger.kernel.org # 3.13+
Fixes: 439a1cfffe ("drm/radeon: expose render backend mask to the userspace")
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7abfabaf5f upstream.
Reading /proc/mdstat with a read buffer size that would not
fit the unused status line in the first read will skip this
line from the output.
So 'dd if=/proc/mdstat bs=64 2>/dev/null' will not print something
like: unused devices: <none>
Don't return NULL immediately in start() for v=2 but call
show() once to print the status line also for multiple reads.
Cc: stable@vger.kernel.org
Fixes: 1f4aace60b ("fs/seq_file.c: simplify seq_file iteration code and interface")
Signed-off-by: Jan Glauber <jglauber@digitalocean.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6a4db2a603 upstream.
commit d3374825ce ("md: make devices disappear when they are no longer
needed.") introduced protection between mddev creating & removing. The
md_open shouldn't create mddev when all_mddevs list doesn't contain
mddev. With currently code logic, there will be very easy to trigger
soft lockup in non-preempt env.
This patch changes md_open returning from -ERESTARTSYS to -EBUSY, which
will break the infinitely retry when md_open enter racing area.
This patch is partly fix soft lockup issue, full fix needs mddev_find
is split into two functions: mddev_find & mddev_find_or_alloc. And
md_open should call new mddev_find (it only does searching job).
For more detail, please refer with Christoph's "split mddev_find" patch
in later commits.
commit 65aa97c4d2 upstream.
Split mddev_find into a simple mddev_find that just finds an existing
mddev by the unit number, and a more complicated mddev_find that deals
with find or allocating a mddev.
This turns out to fix this bug reported by Zhao Heming.
----------------------------- snip ------------------------------
commit d3374825ce ("md: make devices disappear when they are no longer
needed.") introduced protection between mddev creating & removing. The
md_open shouldn't create mddev when all_mddevs list doesn't contain
mddev. With currently code logic, there will be very easy to trigger
soft lockup in non-preempt env.
commit 404a8ef512 upstream.
NULL pointer dereference was observed in super_written() when it tries
to access the mddev structure.
[The below stack trace is from an older kernel, but the problem described
in this patch applies to the mainline kernel.]
[ 1194.474861] task: ffff8fdd20858000 task.stack: ffffb99d40790000
[ 1194.488000] RIP: 0010:super_written+0x29/0xe1
[ 1194.499688] RSP: 0018:ffff8ffb7fcc3c78 EFLAGS: 00010046
[ 1194.512477] RAX: 0000000000000000 RBX: ffff8ffb7bf4a000 RCX: ffff8ffb78991048
[ 1194.527325] RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff8ffb56b8a200
[ 1194.542576] RBP: ffff8ffb7fcc3c90 R08: 000000000000000b R09: 0000000000000000
[ 1194.558001] R10: ffff8ffb56b8a298 R11: 0000000000000000 R12: ffff8ffb56b8a200
[ 1194.573070] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
[ 1194.588117] FS: 0000000000000000(0000) GS:ffff8ffb7fcc0000(0000) knlGS:0000000000000000
[ 1194.604264] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1194.617375] CR2: 00000000000002b8 CR3: 00000021e040a002 CR4: 00000000007606e0
[ 1194.632327] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1194.647865] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 1194.663316] PKRU: 55555554
[ 1194.674090] Call Trace:
[ 1194.683735] <IRQ>
[ 1194.692948] bio_endio+0xae/0x135
[ 1194.703580] blk_update_request+0xad/0x2fa
[ 1194.714990] blk_update_bidi_request+0x20/0x72
[ 1194.726578] __blk_end_bidi_request+0x2c/0x4d
[ 1194.738373] __blk_end_request_all+0x31/0x49
[ 1194.749344] blk_flush_complete_seq+0x377/0x383
[ 1194.761550] flush_end_io+0x1dd/0x2a7
[ 1194.772910] blk_finish_request+0x9f/0x13c
[ 1194.784544] scsi_end_request+0x180/0x25c
[ 1194.796149] scsi_io_completion+0xc8/0x610
[ 1194.807503] scsi_finish_command+0xdc/0x125
[ 1194.818897] scsi_softirq_done+0x81/0xde
[ 1194.830062] blk_done_softirq+0xa4/0xcc
[ 1194.841008] __do_softirq+0xd9/0x29f
[ 1194.851257] irq_exit+0xe6/0xeb
[ 1194.861290] do_IRQ+0x59/0xe3
[ 1194.871060] common_interrupt+0x1c6/0x382
[ 1194.881988] </IRQ>
[ 1194.890646] RIP: 0010:cpuidle_enter_state+0xdd/0x2a5
[ 1194.902532] RSP: 0018:ffffb99d40793e68 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff43
[ 1194.917317] RAX: ffff8ffb7fce27c0 RBX: ffff8ffb7fced800 RCX: 000000000000001f
[ 1194.932056] RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000000
[ 1194.946428] RBP: ffffb99d40793ea0 R08: 0000000000000004 R09: 0000000000002ed2
[ 1194.960508] R10: 0000000000002664 R11: 0000000000000018 R12: 0000000000000003
[ 1194.974454] R13: 000000000000000b R14: ffffffff925715a0 R15: 0000011610120d5a
[ 1194.988607] ? cpuidle_enter_state+0xcc/0x2a5
[ 1194.999077] cpuidle_enter+0x17/0x19
[ 1195.008395] call_cpuidle+0x23/0x3a
[ 1195.017718] do_idle+0x172/0x1d5
[ 1195.026358] cpu_startup_entry+0x73/0x75
[ 1195.035769] start_secondary+0x1b9/0x20b
[ 1195.044894] secondary_startup_64+0xa5/0xa5
[ 1195.084921] RIP: super_written+0x29/0xe1 RSP: ffff8ffb7fcc3c78
[ 1195.096354] CR2: 00000000000002b8
bio in the above stack is a bitmap write whose completion is invoked after
the tear down sequence sets the mddev structure to NULL in rdev.
During tear down, there is an attempt to flush the bitmap writes, but for
external bitmaps, there is no explicit wait for all the bitmap writes to
complete. For instance, md_bitmap_flush() is called to flush the bitmap
writes, but the last call to md_bitmap_daemon_work() in md_bitmap_flush()
could generate new bitmap writes for which there is no explicit wait to
complete those writes. The call to md_bitmap_update_sb() will return
simply for external bitmaps and the follow-up call to md_update_sb() is
conditional and may not get called for external bitmaps. This results in a
kernel panic when the completion routine, super_written() is called which
tries to reference mddev in the rdev that has been set to
NULL(in unbind_rdev_from_array() by tear down sequence).
The solution is to call md_super_wait() for external bitmaps after the
last call to md_bitmap_daemon_work() in md_bitmap_flush() to ensure there
are no pending bitmap writes before proceeding with the tear down.
Cc: stable@vger.kernel.org
Signed-off-by: Sudhakar Panneerselvam <sudhakar.panneerselvam@oracle.com>
Reviewed-by: Zhao Heming <heming.zhao@suse.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
