commit f5eff5591b upstream.
In 2013, commits
2e35afaefe ("PCI: pciehp: Add reset_slot() method")
608c388122 ("PCI: Add slot reset option to pci_dev_reset()")
amended PCIe hotplug to mask Presence Detect Changed events during a
Secondary Bus Reset. The reset thus no longer causes gratuitous slot
bringdown and bringup.
However the commits neglected to serialize reset with code paths reading
slot registers. For instance, a slot bringup due to an earlier hotplug
event may see the Presence Detect State bit cleared during a concurrent
Secondary Bus Reset.
In 2018, commit
5b3f7b7d06 ("PCI: pciehp: Avoid slot access during reset")
retrofitted the missing locking. It introduced a reset_lock which
serializes a Secondary Bus Reset with other parts of pciehp.
Unfortunately the locking turns out to be overzealous: reset_lock is
held for the entire enumeration and de-enumeration of hotplugged devices,
including driver binding and unbinding.
Driver binding and unbinding acquires device_lock while the reset_lock
of the ancestral hotplug port is held. A concurrent Secondary Bus Reset
acquires the ancestral reset_lock while already holding the device_lock.
The asymmetric locking order in the two code paths can lead to AB-BA
deadlocks.
Michael Haeuptle reports such deadlocks on simultaneous hot-removal and
vfio release (the latter implies a Secondary Bus Reset):
pciehp_ist() # down_read(reset_lock)
pciehp_handle_presence_or_link_change()
pciehp_disable_slot()
__pciehp_disable_slot()
remove_board()
pciehp_unconfigure_device()
pci_stop_and_remove_bus_device()
pci_stop_bus_device()
pci_stop_dev()
device_release_driver()
device_release_driver_internal()
__device_driver_lock() # device_lock()
SYS_munmap()
vfio_device_fops_release()
vfio_device_group_close()
vfio_device_close()
vfio_device_last_close()
vfio_pci_core_close_device()
vfio_pci_core_disable() # device_lock()
__pci_reset_function_locked()
pci_reset_bus_function()
pci_dev_reset_slot_function()
pci_reset_hotplug_slot()
pciehp_reset_slot() # down_write(reset_lock)
Ian May reports the same deadlock on simultaneous hot-removal and an
AER-induced Secondary Bus Reset:
aer_recover_work_func()
pcie_do_recovery()
aer_root_reset()
pci_bus_error_reset()
pci_slot_reset()
pci_slot_lock() # device_lock()
pci_reset_hotplug_slot()
pciehp_reset_slot() # down_write(reset_lock)
Fix by releasing the reset_lock during driver binding and unbinding,
thereby splitting and shrinking the critical section.
Driver binding and unbinding is protected by the device_lock() and thus
serialized with a Secondary Bus Reset. There's no need to additionally
protect it with the reset_lock. However, pciehp does not bind and
unbind devices directly, but rather invokes PCI core functions which
also perform certain enumeration and de-enumeration steps.
The reset_lock's purpose is to protect slot registers, not enumeration
and de-enumeration of hotplugged devices. That would arguably be the
job of the PCI core, not the PCIe hotplug driver. After all, an
AER-induced Secondary Bus Reset may as well happen during boot-time
enumeration of the PCI hierarchy and there's no locking to prevent that
either.
Exempting *de-enumeration* from the reset_lock is relatively harmless:
A concurrent Secondary Bus Reset may foil config space accesses such as
PME interrupt disablement. But if the device is physically gone, those
accesses are pointless anyway. If the device is physically present and
only logically removed through an Attention Button press or the sysfs
"power" attribute, PME interrupts as well as DMA cannot come through
because pciehp_unconfigure_device() disables INTx and Bus Master bits.
That's still protected by the reset_lock in the present commit.
Exempting *enumeration* from the reset_lock also has limited impact:
The exempted call to pci_bus_add_device() may perform device accesses
through pcibios_bus_add_device() and pci_fixup_device() which are now
no longer protected from a concurrent Secondary Bus Reset. Otherwise
there should be no impact.
In essence, the present commit seeks to fix the AB-BA deadlocks while
still retaining a best-effort reset protection for enumeration and
de-enumeration of hotplugged devices -- until a general solution is
implemented in the PCI core.
Link: https://lore.kernel.org/linux-pci/CS1PR8401MB0728FC6FDAB8A35C22BD90EC95F10@CS1PR8401MB0728.NAMPRD84.PROD.OUTLOOK.COM
Link: https://lore.kernel.org/linux-pci/20200615143250.438252-1-ian.may@canonical.com
Link: https://lore.kernel.org/linux-pci/ce878dab-c0c4-5bd0-a725-9805a075682d@amd.com
Link: https://lore.kernel.org/linux-pci/ed831249-384a-6d35-0831-70af191e9bce@huawei.com
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215590
Fixes: 5b3f7b7d06 ("PCI: pciehp: Avoid slot access during reset")
Link: https://lore.kernel.org/r/fef2b2e9edf245c049a8c5b94743c0f74ff5008a.1681191902.git.lukas@wunner.de
Reported-by: Michael Haeuptle <michael.haeuptle@hpe.com>
Reported-by: Ian May <ian.may@canonical.com>
Reported-by: Andrey Grodzovsky <andrey2805@gmail.com>
Reported-by: Rahul Kumar <rahul.kumar1@amd.com>
Reported-by: Jialin Zhang <zhangjialin11@huawei.com>
Tested-by: Anatoli Antonovitch <Anatoli.Antonovitch@amd.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org # v4.19+
Cc: Dan Stein <dstein@hpe.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Alex Michon <amichon@kalrayinc.com>
Cc: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Sathyanarayanan Kuppuswamy <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3a2776e8a0 upstream.
pcie-kirin uses regmaps, and needs to pull them in; otherwise, with
CONFIG_PCIE_KIRIN=y and without CONFIG_REGMAP_MMIO pcie-kirin produces
a linker failure looking for __devm_regmap_init_mmio_clk().
Fixes: d19afe7be1 ("PCI: kirin: Use regmap for APB registers")
Link: https://lore.kernel.org/r/04636141da1d6d592174eefb56760511468d035d.1668410580.git.josh@joshtriplett.org
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
[lpieralisi@kernel.org: commit log and removed REGMAP select]
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Cc: stable@vger.kernel.org # 5.16+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 59b37fe52f upstream.
Instead of reloading the shadow call stack pointer from the ordinary
stack, which may be vulnerable to the kind of gadget based attacks
shadow call stacks were designed to prevent, let's store a task's shadow
call stack pointer in the task struct when switching to the shadow IRQ
stack.
Given that currently, the task_struct::scs_sp field is only used to
preserve the shadow call stack pointer while a task is scheduled out or
running in user space, reusing this field to preserve and restore it
while running off the IRQ stack must be safe, as those occurrences are
guaranteed to never overlap. (The stack switching logic only switches
stacks when running from the task stack, and so the value being saved
here always corresponds to the task mode shadow stack)
While at it, fold a mov/add/mov sequence into a single add.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20230109174800.3286265-3-ardb@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2198d07c50 upstream.
All occurrences of the scs_load macro load the value of the shadow call
stack pointer from the task which is current at that point. So instead
of taking a task struct register argument in the scs_load macro to
specify the task struct to load from, let's always reference the current
task directly. This should make it much harder to exploit any
instruction sequences reloading the shadow call stack pointer register
from memory.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230109174800.3286265-2-ardb@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 09d4d6da1b upstream.
When the BIOS has been configured for Fast Boot, systems with mt7921e
have non-functional wifi. Turning on Fast boot caused both bus master
enable and memory space enable bits in PCI_COMMAND not to get configured.
The mt7921 driver already sets bus master enable, but explicitly check
and set memory access enable as well to fix this problem.
Tested-by: Anson Tsao <anson.tsao@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Acked-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit f82e7ca019 ]
A __field() in the TRACE_EVENT() macro is used to set up the fields of the
trace event data. It is for single storage units (word, char, int,
pointer, etc) and not for complex structures or arrays. Unfortunately,
there's nothing preventing the build from accepting:
__field(int, arr[5]);
from building. It will turn into a array value. This use to work fine, as
the offset and size use to be determined by the macro using the field name,
but things have changed and the offset and size are now determined by the
type. So the above would only be size 4, and the next field will be
located 4 bytes from it (instead of 20).
The proper way to declare static arrays is to use the __array() macro.
Instead of __field(int, arr[5]) it should be __array(int, arr, 5).
Add some macro tricks to the building of a trace event from the
TRACE_EVENT() macro such that __field(int, arr[5]) will fail to build. A
comment by the failure will explain why the build failed.
Link: https://lore.kernel.org/lkml/20230306122549.236561-1-douglas.raillard@arm.com/
Link: https://lore.kernel.org/linux-trace-kernel/20230309221302.642e82d9@gandalf.local.home
Reported-by: Douglas RAILLARD <douglas.raillard@arm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit cf5fa3ca05 ]
Currently ath11k breaks after hibernation, the reason being that ath11k expects
that the wireless device will have power during suspend and the firmware will
continue running. But of course during hibernation the power from the device is
cut off and firmware is not running when resuming, so ath11k will fail.
(The reason why ath11k needs the firmware running is the interaction between
mac80211 and MHI stack, it's a long story and more info in the bugzilla report.)
In SUSE kernels the watchdog timeout is reduced from the default 120 to 60 seconds:
CONFIG_DPM_WATCHDOG_TIMEOUT=60
But as the ath11k MHI timeout is 90 seconds the kernel will crash before will
ath11k will recover in resume callback. To avoid the crash reduce the MHI
timeout to just 20 seconds.
Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.9
Link: https://bugzilla.kernel.org/show_bug.cgi?id=214649
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20230329162038.8637-1-kvalo@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit a3d27dfdcf ]
The driver is exiting from the fault watchdog thread if it sees the 0xF002
(Soft reset in progress) fault code.
If the driver initiates the soft reset, then the driver restarts the
watchdog at the end of the soft reset completion. However, if the soft
reset is initiated by the firmware asynchronously, then the driver will
never restart the watchdog and never re-initialize the controller after the
asynchronous soft reset completion.
Signed-off-by: Ranjan Kumar <ranjan.kumar@broadcom.com>
Link: https://lore.kernel.org/r/20230331122317.11391-1-ranjan.kumar@broadcom.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f1594bc676 ]
When compiling selftests with target mount_setattr I encountered some errors with the below messages:
mount_setattr_test.c: In function ‘mount_setattr_thread’:
mount_setattr_test.c:343:16: error: variable ‘attr’ has initializer but incomplete type
343 | struct mount_attr attr = {
| ^~~~~~~~~~
These errors might be because of linux/mount.h is not included. This patch resolves that issue.
Signed-off-by: Anh Tuan Phan <tuananhlfc@gmail.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f8acb24aaf ]
Hyper-V should never specify a VM that is a Confidential VM and also
running in the root partition. Nonetheless, explicitly block such a
combination to guard against a compromised Hyper-V maliciously trying to
exploit root partition functionality in a Confidential VM to expose
Confidential VM secrets. No known bug is being fixed, but the attack
surface for Confidential VMs on Hyper-V is reduced.
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/1678894453-95392-1-git-send-email-mikelley@microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 083a25b18d ]
The hw->formats may be set by snd_dmaengine_pcm_refine_runtime_hwparams()
in component's startup()/open(), but soc_pcm_hw_init() will init
hw->formats in dpcm_runtime_setup_fe() after component's startup()/open(),
which causes the valuable hw->formats to be cleared.
So need to store the hw->formats before initialization, then restore
it after initialization.
Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Link: https://lore.kernel.org/r/1678346017-3660-1-git-send-email-shengjiu.wang@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit ef69d2559f upstream.
riscv establishes 2 virtual mappings:
- early_pg_dir maps the kernel which allows to discover the system
memory
- swapper_pg_dir installs the final mapping (linear mapping included)
We used to map the dtb in early_pg_dir using DTB_EARLY_BASE_VA, and this
mapping was not carried over in swapper_pg_dir. It happens that
early_init_fdt_scan_reserved_mem() must be called before swapper_pg_dir is
setup otherwise we could allocate reserved memory defined in the dtb.
And this function initializes reserved_mem variable with addresses that
lie in the early_pg_dir dtb mapping: when those addresses are reused
with swapper_pg_dir, this mapping does not exist and then we trap.
The previous "fix" was incorrect as early_init_fdt_scan_reserved_mem()
must be called before swapper_pg_dir is set up otherwise we could
allocate in reserved memory defined in the dtb.
So move the dtb mapping in the fixmap region which is established in
early_pg_dir and handed over to swapper_pg_dir.
This patch had to be backported because:
- the documentation for sv57 is not present here (as sv48/57 are not
present)
Fixes: 922b0375fc ("riscv: Fix memblock reservation for device tree blob")
Fixes: 8f3a2b4a96 ("RISC-V: Move DT mapping outof fixmap")
Fixes: 50e63dd8ed ("riscv: fix reserved memory setup")
Reported-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/all/f8e67f82-103d-156c-deb0-d6d6e2756f5e@microchip.com/
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230329081932.79831-2-alexghiti@rivosinc.com
Cc: stable@vger.kernel.org # 6.1.x
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8ba7d5f5ba upstream.
There are some warnings on older compilers (gcc 10, 7) or non-x86_64
architectures (aarch64). As btrfs wants to enable -Wmaybe-uninitialized
by default, fix the warnings even though it's not necessary on recent
compilers (gcc 12+).
../fs/btrfs/volumes.c: In function ‘btrfs_init_new_device’:
../fs/btrfs/volumes.c:2703:3: error: ‘seed_devices’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
2703 | btrfs_setup_sprout(fs_info, seed_devices);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../fs/btrfs/send.c: In function ‘get_cur_inode_state’:
../include/linux/compiler.h:70:32: error: ‘right_gen’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
70 | (__if_trace.miss_hit[1]++,1) : \
| ^
../fs/btrfs/send.c:1878:6: note: ‘right_gen’ was declared here
1878 | u64 right_gen;
| ^~~~~~~~~
Reported-by: k2ci <kernel-bot@kylinos.cn>
Signed-off-by: Genjian Zhang <zhanggenjian@kylinos.cn>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
Cc: Ammar Faizi <ammarfaizi2@gnuweeb.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 25c150ac10 upstream.
Previously, capability was checked using capable(), which verified that the
caller of the ioctl system call had the required capability. In addition,
the result of the check would be stored in the HCI_SOCK_TRUSTED flag,
making it persistent for the socket.
However, malicious programs can abuse this approach by deliberately sharing
an HCI socket with a privileged task. The HCI socket will be marked as
trusted when the privileged task occasionally makes an ioctl call.
This problem can be solved by using sk_capable() to check capability, which
ensures that not only the current task but also the socket opener has the
specified capability, thus reducing the risk of privilege escalation
through the previously identified vulnerability.
Cc: stable@vger.kernel.org
Fixes: f81f5b2db8 ("Bluetooth: Send control open and close messages for HCI raw sockets")
Signed-off-by: Ruihan Li <lrh2000@pku.edu.cn>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 782eea0c89 upstream.
commit 1796f808e4 ("HID: i2c-hid: acpi: Stop setting wakeup_capable")
changed the policy such that I2C touchpads may be able to wake up the
system by default if the system is configured as such.
However on Clevo NL5xNU there is a mistake in the ACPI tables that the
TP_ATTN# signal connected to GPIO 9 is configured as ActiveLow and level
triggered but connected to a pull up. As soon as the system suspends the
touchpad loses power and then the system wakes up.
To avoid this problem, introduce a quirk for this model that will prevent
the wakeup capability for being set for GPIO 9.
This patch is analoge to a very similar patch for NL5xRU, just the DMI
string changed.
Signed-off-by: Werner Sembach <wse@tuxedocomputers.com>
Cc: stable@vger.kernel.org
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f4e9e0e694 upstream.
set_mempolicy_home_node() iterates over a list of VMAs and calls
mbind_range() on each VMA, which also iterates over the singular list of
the VMA passed in and potentially splits the VMA. Since the VMA iterator
is not passed through, set_mempolicy_home_node() may now point to a stale
node in the VMA tree. This can result in a UAF as reported by syzbot.
Avoid the stale maple tree node by passing the VMA iterator through to the
underlying call to split_vma().
mbind_range() is also overly complicated, since there are two calling
functions and one already handles iterating over the VMAs. Simplify
mbind_range() to only handle merging and splitting of the VMAs.
Align the new loop in do_mbind() and existing loop in
set_mempolicy_home_node() to use the reduced mbind_range() function. This
allows for a single location of the range calculation and avoids
constantly looking up the previous VMA (since this is a loop over the
VMAs).
Link: https://lore.kernel.org/linux-mm/000000000000c93feb05f87e24ad@google.com/
Fixes: 66850be55e ("mm/mempolicy: use vma iterator & maple state instead of vma linked list")
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reported-by: syzbot+a7c1ec5b1d71ceaa5186@syzkaller.appspotmail.com
Link: https://lkml.kernel.org/r/20230410152205.2294819-1-Liam.Howlett@oracle.com
Tested-by: syzbot+a7c1ec5b1d71ceaa5186@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 13ec9308a8 upstream.
Read mmu_invalidate_seq before dropping the mmap_lock so that KVM can
detect if the results of vma_lookup() (e.g. vma_shift) become stale
before it acquires kvm->mmu_lock. This fixes a theoretical bug where a
VMA could be changed by userspace after vma_lookup() and before KVM
reads the mmu_invalidate_seq, causing KVM to install page table entries
based on a (possibly) no-longer-valid vma_shift.
Re-order the MMU cache top-up to earlier in user_mem_abort() so that it
is not done after KVM has read mmu_invalidate_seq (i.e. so as to avoid
inducing spurious fault retries).
This bug has existed since KVM/ARM's inception. It's unlikely that any
sane userspace currently modifies VMAs in such a way as to trigger this
race. And even with directed testing I was unable to reproduce it. But a
sufficiently motivated host userspace might be able to exploit this
race.
Fixes: 94f8e6418d ("KVM: ARM: Handle guest faults in KVM")
Cc: stable@vger.kernel.org
Reported-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230313235454.2964067-1-dmatlack@google.com
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
[will: Use FSC_PERM instead of ESR_ELx_FSC_PERM]
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 86a24e99c9 upstream.
dma_request_slave_channel() may return NULL which will lead to
NULL pointer dereference error in 'tmp_chan->private'.
Correct this behaviour by, first, switching from deprecated function
dma_request_slave_channel() to dma_request_chan(). Secondly, enable
sanity check for the resuling value of dma_request_chan().
Also, fix description that follows the enacted changes and that
concerns the use of dma_request_slave_channel().
Fixes: 706e2c8811 ("ASoC: fsl_asrc_dma: Reuse the dma channel if available in Back-End")
Co-developed-by: Natalia Petrova <n.petrova@fintech.ru>
Signed-off-by: Nikita Zhandarovich <n.zhandarovich@fintech.ru>
Acked-by: Shengjiu Wang <shengjiu.wang@gmail.com>
Link: https://lore.kernel.org/r/20230417133242.53339-1-n.zhandarovich@fintech.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0b186bb061 upstream.
With PCI if the device was suspended it is brought back to full
power and then suspended again.
This doesn't happen when device is described via DT.
We need to make sure that we tear down pipelines only if the device
was previously active (thus the pipelines were setup).
Otherwise, we can break the use_count:
[ 219.009743] sof-audio-of-imx8m 3b6e8000.dsp:
sof_ipc3_tear_down_all_pipelines: widget PIPELINE.2.SAI3.IN is still in use: count -1
and after this everything stops working.
Fixes: d185e0689a ("ASoC: SOF: pm: Always tear down pipelines before DSP suspend")
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
Link: https://lore.kernel.org/r/20230405092655.19587-1-daniel.baluta@oss.nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1007843a91 upstream.
syzbot is reporting circular locking dependency which involves
zonelist_update_seq seqlock [1], for this lock is checked by memory
allocation requests which do not need to be retried.
One deadlock scenario is kmalloc(GFP_ATOMIC) from an interrupt handler.
CPU0
----
__build_all_zonelists() {
write_seqlock(&zonelist_update_seq); // makes zonelist_update_seq.seqcount odd
// e.g. timer interrupt handler runs at this moment
some_timer_func() {
kmalloc(GFP_ATOMIC) {
__alloc_pages_slowpath() {
read_seqbegin(&zonelist_update_seq) {
// spins forever because zonelist_update_seq.seqcount is odd
}
}
}
}
// e.g. timer interrupt handler finishes
write_sequnlock(&zonelist_update_seq); // makes zonelist_update_seq.seqcount even
}
This deadlock scenario can be easily eliminated by not calling
read_seqbegin(&zonelist_update_seq) from !__GFP_DIRECT_RECLAIM allocation
requests, for retry is applicable to only __GFP_DIRECT_RECLAIM allocation
requests. But Michal Hocko does not know whether we should go with this
approach.
Another deadlock scenario which syzbot is reporting is a race between
kmalloc(GFP_ATOMIC) from tty_insert_flip_string_and_push_buffer() with
port->lock held and printk() from __build_all_zonelists() with
zonelist_update_seq held.
CPU0 CPU1
---- ----
pty_write() {
tty_insert_flip_string_and_push_buffer() {
__build_all_zonelists() {
write_seqlock(&zonelist_update_seq);
build_zonelists() {
printk() {
vprintk() {
vprintk_default() {
vprintk_emit() {
console_unlock() {
console_flush_all() {
console_emit_next_record() {
con->write() = serial8250_console_write() {
spin_lock_irqsave(&port->lock, flags);
tty_insert_flip_string() {
tty_insert_flip_string_fixed_flag() {
__tty_buffer_request_room() {
tty_buffer_alloc() {
kmalloc(GFP_ATOMIC | __GFP_NOWARN) {
__alloc_pages_slowpath() {
zonelist_iter_begin() {
read_seqbegin(&zonelist_update_seq); // spins forever because zonelist_update_seq.seqcount is odd
spin_lock_irqsave(&port->lock, flags); // spins forever because port->lock is held
}
}
}
}
}
}
}
}
spin_unlock_irqrestore(&port->lock, flags);
// message is printed to console
spin_unlock_irqrestore(&port->lock, flags);
}
}
}
}
}
}
}
}
}
write_sequnlock(&zonelist_update_seq);
}
}
}
This deadlock scenario can be eliminated by
preventing interrupt context from calling kmalloc(GFP_ATOMIC)
and
preventing printk() from calling console_flush_all()
while zonelist_update_seq.seqcount is odd.
Since Petr Mladek thinks that __build_all_zonelists() can become a
candidate for deferring printk() [2], let's address this problem by
disabling local interrupts in order to avoid kmalloc(GFP_ATOMIC)
and
disabling synchronous printk() in order to avoid console_flush_all()
.
As a side effect of minimizing duration of zonelist_update_seq.seqcount
being odd by disabling synchronous printk(), latency at
read_seqbegin(&zonelist_update_seq) for both !__GFP_DIRECT_RECLAIM and
__GFP_DIRECT_RECLAIM allocation requests will be reduced. Although, from
lockdep perspective, not calling read_seqbegin(&zonelist_update_seq) (i.e.
do not record unnecessary locking dependency) from interrupt context is
still preferable, even if we don't allow calling kmalloc(GFP_ATOMIC)
inside
write_seqlock(&zonelist_update_seq)/write_sequnlock(&zonelist_update_seq)
section...
Link: https://lkml.kernel.org/r/8796b95c-3da3-5885-fddd-6ef55f30e4d3@I-love.SAKURA.ne.jp
Fixes: 3d36424b3b ("mm/page_alloc: fix race condition between build_all_zonelists and page allocation")
Link: https://lkml.kernel.org/r/ZCrs+1cDqPWTDFNM@alley [2]
Reported-by: syzbot <syzbot+223c7461c58c58a4cb10@syzkaller.appspotmail.com>
Link: https://syzkaller.appspot.com/bug?extid=223c7461c58c58a4cb10 [1]
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Petr Mladek <pmladek@suse.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Patrick Daly <quic_pdaly@quicinc.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
