Link: https://lore.kernel.org/r/20230515161722.146344674@linuxfoundation.org Tested-by: Chris Paterson (CIP) <chris.paterson2@renesas.com> Tested-by: Shuah Khan <skhan@linuxfoundation.org> Tested-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk> Tested-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com> Tested-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit da5e14909776edea4462672fb4a3007802d262e7 upstream. [Why&How] When skipping full modeset since the only state change was a front porch change, the DC commit sequence requires extra checks to handle non existant plane states being asked to be removed from context. Reviewed-by: Alvin Lee <Alvin.Lee2@amd.com> Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com> Signed-off-by: Aurabindo Pillai <aurabindo.pillai@amd.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1007843a91909a4995ee78a538f62d8665705b66 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: 3d36424b3b58 ("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>
commit a4e5eed2c6a689ef2b6ad8d7ae86665c69039379 upstream. After this patch cbe16f35bee68 genirq: Add IRQF_NO_AUTOEN for request_irq/nmi() is merged. request_irq() after setting IRQ_NOAUTOEN as below irq_set_status_flags(irq, IRQ_NOAUTOEN); request_irq(dev, irq...); can be replaced by request_irq() with IRQF_NO_AUTOEN flag. v2: Fix the problem of using wrong flags Signed-off-by: Tian Tao <tiantao6@hisilicon.com> Signed-off-by: Inki Dae <inki.dae@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dbeedbcb268d055d8895aceca427f897e12c2b50 upstream.
Fix the below kernel panic due to null pointer access:
[ 18.504431] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000048
[ 18.513464] Mem abort info:
[ 18.516346] ESR = 0x0000000096000005
[ 18.520204] EC = 0x25: DABT (current EL), IL = 32 bits
[ 18.525706] SET = 0, FnV = 0
[ 18.528878] EA = 0, S1PTW = 0
[ 18.532117] FSC = 0x05: level 1 translation fault
[ 18.537138] Data abort info:
[ 18.540110] ISV = 0, ISS = 0x00000005
[ 18.544060] CM = 0, WnR = 0
[ 18.547109] user pgtable: 4k pages, 39-bit VAs, pgdp=0000000112826000
[ 18.553738] [0000000000000048] pgd=0000000000000000, p4d=0000000000000000, pud=0000000000000000
[ 18.562690] Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
**Snip**
[ 18.696758] Call trace:
[ 18.699278] adreno_gpu_cleanup+0x30/0x88
[ 18.703396] a6xx_destroy+0xc0/0x130
[ 18.707066] a6xx_gpu_init+0x308/0x424
[ 18.710921] adreno_bind+0x178/0x288
[ 18.714590] component_bind_all+0xe0/0x214
[ 18.718797] msm_drm_bind+0x1d4/0x614
[ 18.722566] try_to_bring_up_aggregate_device+0x16c/0x1b8
[ 18.728105] __component_add+0xa0/0x158
[ 18.732048] component_add+0x20/0x2c
[ 18.735719] adreno_probe+0x40/0xc0
[ 18.739300] platform_probe+0xb4/0xd4
[ 18.743068] really_probe+0xfc/0x284
[ 18.746738] __driver_probe_device+0xc0/0xec
[ 18.751129] driver_probe_device+0x48/0x110
[ 18.755421] __device_attach_driver+0xa8/0xd0
[ 18.759900] bus_for_each_drv+0x90/0xdc
[ 18.763843] __device_attach+0xfc/0x174
[ 18.767786] device_initial_probe+0x20/0x2c
[ 18.772090] bus_probe_device+0x40/0xa0
[ 18.776032] deferred_probe_work_func+0x94/0xd0
[ 18.780686] process_one_work+0x190/0x3d0
[ 18.784805] worker_thread+0x280/0x3d4
[ 18.788659] kthread+0x104/0x1c0
[ 18.791981] ret_from_fork+0x10/0x20
[ 18.795654] Code: f9400408 aa0003f3 aa1f03f4 91142015 (f9402516)
[ 18.801913] ---[ end trace 0000000000000000 ]---
[ 18.809039] Kernel panic - not syncing: Oops: Fatal exception
Fixes: 17e822f7591f ("drm/msm: fix unbalanced pm_runtime_enable in adreno_gpu_{init, cleanup}")
Signed-off-by: Akhil P Oommen <quic_akhilpo@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/515605/
Link: https://lore.kernel.org/r/20221221203925.v2.1.Ib978de92c4bd000b515486aad72e96c2481f84d0@changeid
Signed-off-by: Rob Clark <robdclark@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7b51161696e803fd5f9ad55b20a64c2df313f95c upstream.
In rpi_firmware_probe(), if mbox_request_channel() fails, the 'fw' will
not be freed through rpi_firmware_delete(), fix this leak by calling
kfree() in the error path.
Fixes: 1e7c57355a3b ("firmware: raspberrypi: Keep count of all consumers")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20221117070636.3849773-1-yangyingliang@huawei.com
Acked-by: Joel Savitz <jsavitz@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ce0db505bc0c51ef5e9ba446c660de7e26f78f29 upstream.
Following commit 17e822f7591f ("drm/msm: fix unbalanced
pm_runtime_enable in adreno_gpu_{init, cleanup}"), any call to
adreno_unbind() will disable runtime PM twice, as indicated by the call
trees below:
adreno_unbind()
-> pm_runtime_force_suspend()
-> pm_runtime_disable()
adreno_unbind()
-> gpu->funcs->destroy() [= aNxx_destroy()]
-> adreno_gpu_cleanup()
-> pm_runtime_disable()
Note that pm_runtime_force_suspend() is called right before
gpu->funcs->destroy() and both functions are called unconditionally.
With recent addition of the eDP AUX bus code, this problem manifests
itself when the eDP panel cannot be found yet and probing is deferred.
On the first probe attempt, we disable runtime PM twice as described
above. This then causes any later probe attempt to fail with
[drm:adreno_load_gpu [msm]] *ERROR* Couldn't power up the GPU: -13
preventing the driver from loading.
As there seem to be scenarios where the aNxx_destroy() functions are not
called from adreno_unbind(), simply removing pm_runtime_disable() from
inside adreno_unbind() does not seem to be the proper fix. This is what
commit 17e822f7591f ("drm/msm: fix unbalanced pm_runtime_enable in
adreno_gpu_{init, cleanup}") intended to fix. Therefore, instead check
whether runtime PM is still enabled, and only disable it in that case.
Fixes: 17e822f7591f ("drm/msm: fix unbalanced pm_runtime_enable in adreno_gpu_{init, cleanup}")
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Tested-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Link: https://lore.kernel.org/r/20220606211305.189585-1-luzmaximilian@gmail.com
Signed-off-by: Rob Clark <robdclark@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit afb0367a80553e795e7ad055299096544454f3f6 upstream.
The rename of generic_pm_domain.slave_links to
generic_pm_domain.child_links accidentally dropped the TAB to align the
member's comment. Re-add the lost TAB to restore indentation.
Fixes: 8d87ae48ced2dffd ("PM: domains: Fix up terminology with parent/child")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
[ rjw: Minor subject edit ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 85e3e7fbbb720b9897fba9a99659e31cbd1c082e upstream.
[This patch implements subset of original commit 85e3e7fbbb72 ("printk:
remove NMI tracking") where commit 1007843a9190 ("mm/page_alloc: fix
potential deadlock on zonelist_update_seq seqlock") depends on, for
commit 3d36424b3b58 ("mm/page_alloc: fix race condition between
build_all_zonelists and page allocation") was backported to stable.]
All NMI contexts are handled the same as the safe context: store the
message and defer printing. There is no need to have special NMI
context tracking for this. Using in_nmi() is enough.
There are several parts of the kernel that are manually calling into
the printk NMI context tracking in order to cause general printk
deferred printing:
arch/arm/kernel/smp.c
arch/powerpc/kexec/crash.c
kernel/trace/trace.c
For arm/kernel/smp.c and powerpc/kexec/crash.c, provide a new
function pair printk_deferred_enter/exit that explicitly achieves the
same objective.
For ftrace, remove the printk context manipulation completely. It was
added in commit 03fc7f9c99c1 ("printk/nmi: Prevent deadlock when
accessing the main log buffer in NMI"). The purpose was to enforce
storing messages directly into the ring buffer even in NMI context.
It really should have only modified the behavior in NMI context.
There is no need for a special behavior any longer. All messages are
always stored directly now. The console deferring is handled
transparently in vprintk().
Signed-off-by: John Ogness <john.ogness@linutronix.de>
[pmladek@suse.com: Remove special handling in ftrace.c completely.
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210715193359.25946-5-john.ogness@linutronix.de
[penguin-kernel: Copy only printk_deferred_{enter,safe}() definition ]
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f5eff5591b8f9c5effd25c92c758a127765f74c1 upstream.
In 2013, commits
2e35afaefe64 ("PCI: pciehp: Add reset_slot() method")
608c388122c7 ("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
5b3f7b7d062b ("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: 5b3f7b7d062b ("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>