Use a u64 instead of a u8 when taking a snapshot of pmu->fixed_ctr_ctrl
when reprogramming fixed counters, as truncating the value results in KVM
thinking fixed counter 2 is already disabled (the bug also affects fixed
counters 3+, but KVM doesn't yet support those). As a result, if the
guest disables fixed counter 2, KVM will get a false negative and fail to
reprogram/disable emulation of the counter, which can leads to incorrect
counts and spurious PMIs in the guest.
Fixes: 76d287b2342e ("KVM: x86/pmu: Drop "u8 ctrl, int idx" for reprogram_fixed_counter()") Cc: stable@vger.kernel.org Signed-off-by: Mingwei Zhang <mizhang@google.com> Link: https://lore.kernel.org/r/20240123221220.3911317-1-mizhang@google.com
[sean: rewrite changelog to call out the effects of the bug] Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kvm_vcpu_ioctl_x86_set_vcpu_events() routine makes 'KVM_REQ_NMI'
request for a vcpu even when its 'events->nmi.pending' is zero.
Ex:
qemu_thread_start
kvm_vcpu_thread_fn
qemu_wait_io_event
qemu_wait_io_event_common
process_queued_cpu_work
do_kvm_cpu_synchronize_post_init/_reset
kvm_arch_put_registers
kvm_put_vcpu_events (cpu, level=[2|3])
This leads vCPU threads in QEMU to constantly acquire & release the
global mutex lock, delaying the guest boot due to lock contention.
Add check to make KVM_REQ_NMI request only if vcpu has NMI pending.
Fixes: bdedff263132 ("KVM: x86: Route pending NMIs from userspace through process_nmi()") Cc: stable@vger.kernel.org Signed-off-by: Prasad Pandit <pjp@fedoraproject.org> Link: https://lore.kernel.org/r/20240103075343.549293-1-ppandit@redhat.com Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Before this change, the expected size of the user space buffer was
taken from fx_sw->xstate_size. fx_sw->xstate_size can be changed
from user-space, so it is possible construct a sigreturn frame where:
* fx_sw->xstate_size is smaller than the size required by valid bits in
fx_sw->xfeatures.
* user-space unmaps parts of the sigrame fpu buffer so that not all of
the buffer required by xrstor is accessible.
In this case, xrstor tries to restore and accesses the unmapped area
which results in a fault. But fault_in_readable succeeds because buf +
fx_sw->xstate_size is within the still mapped area, so it goes back and
tries xrstor again. It will spin in this loop forever.
Instead, fault in the maximum size which can be touched by XRSTOR (taken
from fpstate->user_size).
[ dhansen: tweak subject / changelog ]
Fixes: fcb3635f5018 ("x86/fpu/signal: Handle #PF in the direct restore path") Reported-by: Konstantin Bogomolov <bogomolov@google.com> Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrei Vagin <avagin@google.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc:stable@vger.kernel.org Link: https://lore.kernel.org/all/20240130063603.3392627-1-avagin%40google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The kernel built with MCRUSOE is unbootable on Transmeta Crusoe. It shows
the following error message:
This kernel requires an i686 CPU, but only detected an i586 CPU.
Unable to boot - please use a kernel appropriate for your CPU.
Remove MCRUSOE from the condition introduced in commit in Fixes, effectively
changing X86_MINIMUM_CPU_FAMILY back to 5 on that machine, which matches the
CPU family given by CPUID.
[ bp: Massage commit message. ]
Fixes: 25d76ac88821 ("x86/Kconfig: Explicitly enumerate i686-class CPUs in Kconfig") Signed-off-by: Aleksander Mazur <deweloper@wp.pl> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: H. Peter Anvin <hpa@zytor.com> Cc: <stable@kernel.org> Link: https://lore.kernel.org/r/20240123134309.1117782-1-deweloper@wp.pl Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Emil reports:
After updating Linux on an i.MX28 board, serial communication over
AUART broke. When I TX from the board and measure on the TX pin, it
seems like the HW fifo is not emptied before the transmission is
stopped.
MXS performs weird things with stop_tx(). The driver makes it
conditional on uart_tx_stopped().
So the driver needs special handling. Pass the brand new UART_TX_NOSTOP
to uart_port_tx_flags() and handle the stop on its own.
Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org> Reported-by: Emil Kronborg <emil.kronborg@protonmail.com> Cc: stable <stable@kernel.org> Fixes: 2d141e683e9a ("tty: serial: use uart_port_tx() helper") Closes: https://lore.kernel.org/all/miwgbnvy3hjpnricubg76ytpn7xoceehwahupy25bubbduu23s@om2lptpa26xw/ Tested-by: Stefan Wahren <wahrenst@gmx.net> Tested-by: Emil Kronborg <emil.kronborg@protonmail.com> Link: https://lore.kernel.org/r/20240201105557.28043-2-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
And an enum with a flag: UART_TX_NOSTOP. To NOT call
__port->ops->stop_tx() when the circular buffer is empty. mxs-uart needs
this (see the next patch).
powerVM hypervisor updates the VPA fields with stolen time data.
It currently reports enqueue_dispatch_tb and ready_enqueue_tb for
this purpose. In linux these two fields are used to report the stolen time.
The VPA fields are updated at the TB frequency. On powerPC its mostly
set at 512Mhz. Hence this needs a conversion to ns when reporting it
back as rest of the kernel timings are in ns. This conversion is already
handled in tb_to_ns function. So use that function to report accurate
stolen time.
Observed this issue and used an Capped Shared Processor LPAR(SPLPAR) to
simplify the experiments. In all these cases, 100% VP Load is run using
stress-ng workload. Values of stolen time is in percentages as reported
by mpstat. With the patch values are close to expected.
Commit e320a76db4b0 ("powerpc/cputable: Split cpu_specs[] out of
cputable.h") moved the cpu_specs to separate header files. Previously
PPC_FEATURE_BOOKE was enabled by CONFIG_PPC_BOOK3E_64. The definition in
cpu_specs_e500mc.h for PPC64 no longer enables PPC_FEATURE_BOOKE.
This breaks user space reading the ELF hwcaps and expect
PPC_FEATURE_BOOKE. Debugging an application with gdb is no longer
working on e5500/e6500 because the 64-bit detection relies on
PPC_FEATURE_BOOKE for Book-E.
Fixes: e320a76db4b0 ("powerpc/cputable: Split cpu_specs[] out of cputable.h") Cc: stable@vger.kernel.org # v6.1+ Signed-off-by: David Engraf <david.engraf@sysgo.com> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20240207092758.1058893-1-david.engraf@sysgo.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Nysal reported that userspace backtraces are missing in offcputime bcc
tool. As an example:
$ sudo ./bcc/tools/offcputime.py -uU
Tracing off-CPU time (us) of user threads by user stack... Hit Ctrl-C to end.
The offcputime bcc tool attaches a bpf program to a kprobe on
finish_task_switch(), which is usually hit on a syscall from userspace.
With the switch to system call vectored, we started setting
pt_regs->link to zero. This is because system call vectored behaves like
a function call with LR pointing to the system call return address, and
with no modification to SRR0/SRR1. The LR value does indicate our next
instruction, so it is being saved as pt_regs->nip, and pt_regs->link is
being set to zero. This is not a problem by itself, but BPF uses perf
callchain infrastructure for capturing stack traces, and that stores LR
as the second entry in the stack trace. perf has code to cope with the
second entry being zero, and skips over it. However, generic userspace
unwinders assume that a zero entry indicates end of the stack trace,
resulting in a truncated userspace stack trace.
Rather than fixing all userspace unwinders to ignore/skip past the
second entry, store the real LR value in pt_regs->link so that there
continues to be a valid, though duplicate entry in the stack trace.
With this change:
$ sudo ./bcc/tools/offcputime.py -uU
Tracing off-CPU time (us) of user threads by user stack... Hit Ctrl-C to end.
The commit 60c8971899f3 ("ftrace: Make DIRECT_CALLS work WITH_ARGS
and !WITH_REGS") changed DIRECT_CALLS to use SAVE_ARGS when there
are multiple ftrace_ops at the same function, but since the x86 only
support to jump to direct_call from ftrace_regs_caller, when we set
the function tracer on the same target function on x86, ftrace-direct
does not work as below (this actually works on arm64.)
At first, insmod ftrace-direct.ko to put a direct_call on
'wake_up_process()'.
# insmod kernel/samples/ftrace/ftrace-direct.ko
# less trace
...
<idle>-0 [006] ..s1. 564.686958: my_direct_func: waking up rcu_preempt-17
<idle>-0 [007] ..s1. 564.687836: my_direct_func: waking up kcompactd0-63
<idle>-0 [006] ..s1. 564.690926: my_direct_func: waking up rcu_preempt-17
<idle>-0 [006] ..s1. 564.696872: my_direct_func: waking up rcu_preempt-17
<idle>-0 [007] ..s1. 565.191982: my_direct_func: waking up kcompactd0-63
Setup a function filter to the 'wake_up_process' too, and enable it.
Then, only function tracer is shown on x86.
But if you enable 'kprobe on ftrace' event (which uses SAVE_REGS flag)
on the same function, it is shown again.
If there is a problem after resetting a port, the do/while() loop that
checks the default value of DIVLSB register may run forever and spam the
I2C bus.
Add a delay before each read of DIVLSB, and a maximum number of tries to
prevent that situation from happening.
Some people are seeing a warning similar to this when using a crystal:
max310x 11-006c: clock is not stable yet
The datasheet doesn't mention the maximum time to wait for the clock to be
stable when using a crystal, and it seems that the 10ms delay in the driver
is not always sufficient.
Jan Kundrát reported that it took three tries (each separated by 10ms) to
get a stable clock.
Modify behavior to check stable clock ready bit multiple times (20), and
waiting 10ms between each try.
Note: the first draft of the driver originally used a 50ms delay, without
checking the clock stable bit.
Then a loop with 1000 retries was implemented, each time reading the clock
stable bit.
In uart_tiocmget():
result = uport->mctrl;
uart_port_lock_irq(uport);
result |= uport->ops->get_mctrl(uport);
uart_port_unlock_irq(uport);
...
return result;
An atomicity violation is identified due to the concurrent execution of
uart_tiocmget() and uart_update_mctrl(). After assigning
result = uport->mctrl, the mctrl value may change in uart_update_mctrl(),
leading to a mismatch between the value returned by
uport->ops->get_mctrl(uport) and the mctrl value previously read.
This can result in uart_tiocmget() returning an incorrect value.
This possible bug is found by an experimental static analysis tool
developed by our team, BassCheck[1]. This tool analyzes the locking APIs
to extract function pairs that can be concurrently executed, and then
analyzes the instructions in the paired functions to identify possible
concurrency bugs including data races and atomicity violations. The above
possible bug is reported when our tool analyzes the source code of
Linux 5.17.
To address this issue, it is suggested to move the line
result = uport->mctrl inside the uart_port_lock block to ensure atomicity
and prevent the mctrl value from being altered during the execution of
uart_tiocmget(). With this patch applied, our tool no longer reports the
bug, with the kernel configuration allyesconfig for x86_64. Due to the
absence of the requisite hardware, we are unable to conduct runtime
testing of the patch. Therefore, our verification is solely based on code
logic analysis.
[1] https://sites.google.com/view/basscheck/
Fixes: c5f4644e6c8b ("[PATCH] Serial: Adjust serial locking") Cc: stable@vger.kernel.org Signed-off-by: Gui-Dong Han <2045gemini@gmail.com> Link: https://lore.kernel.org/r/20240112113624.17048-1-2045gemini@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The nfp driver will merge the tp source port and tp destination port
into one dword which the offset must be zero to do hardware offload.
However, the mangle action for the tp source port and tp destination
port is separated for tc ct action. Modify the mangle action for the
FLOW_ACT_MANGLE_HDR_TYPE_TCP and FLOW_ACT_MANGLE_HDR_TYPE_UDP to
satisfy the nfp driver offload check for the tp port.
The mangle action provides a 4B value for source, and a 4B value for
the destination, but only 2B of each contains the useful information.
For offload the 2B of each is combined into a single 4B word. Since the
incoming mask for the source is '0xFFFF<mask>' the shift-left will
throw away the 0xFFFF part. When this gets combined together in the
offload it will clear the destination field. Fix this by setting the
lower bits back to 0xFFFF, effectively doing a rotate-left operation on
the mask.
Fixes: 5cee92c6f57a ("nfp: flower: support hw offload for ct nat action") CC: stable@vger.kernel.org # 6.1+ Signed-off-by: Hui Zhou <hui.zhou@corigine.com> Signed-off-by: Louis Peens <louis.peens@corigine.com> Link: https://lore.kernel.org/r/20240124151909.31603-3-louis.peens@corigine.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The nfp offload flow pay will not allocate a mask id when the out port
is openvswitch internal port. This is because these flows are used to
configure the pre_tun table and are never actually send to the firmware
as an add-flow message. When a tc rule which action contains ct and
the post ct entry's out port is openvswitch internal port, the merge
offload flow pay with the wrong mask id of 0 will be send to the
firmware. Actually, the nfp can not support hardware offload for this
situation, so return EOPNOTSUPP.
Fixes: bd0fe7f96a3c ("nfp: flower-ct: add zone table entry when handling pre/post_ct flows") CC: stable@vger.kernel.org # 5.14+ Signed-off-by: Hui Zhou <hui.zhou@corigine.com> Signed-off-by: Louis Peens <louis.peens@corigine.com> Link: https://lore.kernel.org/r/20240124151909.31603-2-louis.peens@corigine.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Not all mv88e6xxx device support C45 read/write operations. Those
which do not return -EOPNOTSUPP. However, when phylib scans the bus,
it considers this fatal, and the probe of the MDIO bus fails, which in
term causes the mv88e6xxx probe as a whole to fail.
When there is no device on the bus for a given address, the pull up
resistor on the data line results in the read returning 0xffff. The
phylib core code understands this when scanning for devices on the
bus. C45 allows multiple devices to be supported at one address, so
phylib will perform a few reads at each address, so although thought
not the most efficient solution, it is a way to avoid fatal
errors. Make use of this as a minimal fix for stable to fix the
probing problems.
Follow up patches will rework how C45 operates to make it similar to
C22 which considers -ENODEV as a none-fatal, and swap mv88e6xxx to
using this.
Cc: stable@vger.kernel.org Fixes: 743a19e38d02 ("net: dsa: mv88e6xxx: Separate C22 and C45 transactions") Reported-by: Tim Menninger <tmenninger@purestorage.com> Signed-off-by: Andrew Lunn <andrew@lunn.ch> Link: https://lore.kernel.org/r/20240129224948.1531452-1-andrew@lunn.ch Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The return type for ring_buffer_poll_wait() is __poll_t. This is behind
the scenes an unsigned where we can set event bits. In case of a
non-allocated CPU, we do return instead -EINVAL (0xffffffea). Lucky us,
this ends up setting few error bits (EPOLLERR | EPOLLHUP | EPOLLNVAL), so
user-space at least is aware something went wrong.
Nonetheless, this is an incorrect code. Replace that -EINVAL with a
proper EPOLLERR to clean that output. As this doesn't change the
behaviour, there's no need to treat this change as a bug fix.
Link: https://lore.kernel.org/linux-trace-kernel/20240131140955.3322792-1-vdonnefort@google.com Cc: stable@vger.kernel.org Fixes: 6721cb6002262 ("ring-buffer: Do not poll non allocated cpu buffers") Signed-off-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In commit ac5047671758 ("hv_netvsc: Disable NAPI before closing the
VMBus channel"), napi_disable was getting called for all channels,
including all subchannels without confirming if they are enabled or not.
This caused hv_netvsc getting hung at napi_disable, when netvsc_probe()
has finished running but nvdev->subchan_work has not started yet.
netvsc_subchan_work() -> rndis_set_subchannel() has not created the
sub-channels and because of that netvsc_sc_open() is not running.
netvsc_remove() calls cancel_work_sync(&nvdev->subchan_work), for which
netvsc_subchan_work did not run.
netif_napi_add() sets the bit NAPI_STATE_SCHED because it ensures NAPI
cannot be scheduled. Then netvsc_sc_open() -> napi_enable will clear the
NAPIF_STATE_SCHED bit, so it can be scheduled. napi_disable() does the
opposite.
Now during netvsc_device_remove(), when napi_disable is called for those
subchannels, napi_disable gets stuck on infinite msleep.
This fix addresses this problem by ensuring that napi_disable() is not
getting called for non-enabled NAPI struct.
But netif_napi_del() is still necessary for these non-enabled NAPI struct
for cleanup purpose.
[Why]
The original picture aspect ratio in mode struct may have chance be
overwritten with wrong aspect ratio data in create_stream_for_sink().
It will create a different VIC output and cause HDMI compliance test
failed.
[How]
Preserve the original picture aspect ratio data during create the
stream.
Cc: Mario Limonciello <mario.limonciello@amd.com> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: stable@vger.kernel.org Reviewed-by: Aurabindo Pillai <aurabindo.pillai@amd.com> Signed-off-by: Tom Chung <chiahsuan.chung@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>
[Why]
There is a potential memory access violation while
iterating through array of dcn35 clks.
[How]
Limit iteration per array size.
Cc: Mario Limonciello <mario.limonciello@amd.com> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: stable@vger.kernel.org Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com> Acked-by: Aurabindo Pillai <aurabindo.pillai@amd.com> Signed-off-by: Roman Li <roman.li@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>
After a recent change in LLVM, allmodconfig (which has CONFIG_KCSAN=y
and CONFIG_WERROR=y enabled) has a few new instances of
-Wframe-larger-than for the mode support and system configuration
functions:
Without the sanitizers enabled, there are no warnings.
This was the catalyst for commit 6740ec97bcdb ("drm/amd/display:
Increase frame warning limit with KASAN or KCSAN in dml2") and that same
change was made to dml in commit 5b750b22530f ("drm/amd/display:
Increase frame warning limit with KASAN or KCSAN in dml") but the
frame_warn_flag variable was not applied to all files. Do so now to
clear up the warnings and make all these files consistent.
With a second DP monitor connected, drm_atomic_state in dm atomic check
sequence does not include the connector state for the old/existing/first
DP monitor. In such case, dsc determination policy would hit a null ptr
when it tries to iterate the old/existing stream that does not have a
valid connector state attached to it. When that happens, dm atomic check
should call drm_atomic_get_connector_state for a new connector state.
Existing dm has already done that, except for RV due to it does not have
official support of dsc where .num_dsc is not defined in dcn10 resource
cap, that prevent from getting drm_atomic_get_connector_state called.
So, skip dsc determination policy for ASICs that don't have DSC support.
Cc: stable@vger.kernel.org # 6.1+ Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2314 Reviewed-by: Wayne Lin <wayne.lin@amd.com> Acked-by: Hamza Mahfooz <hamza.mahfooz@amd.com> Signed-off-by: Fangzhi Zuo <jerry.zuo@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Without unsigned long typecast, the size is passed in as zero if page
array size >= 4GB, nr_pages >= 0x100000, then sg list converted will
have the first and the last chunk lost.
Signed-off-by: Philip Yang <Philip.Yang@amd.com> Acked-by: Felix Kuehling <Felix.Kuehling@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com> CC: stable@vger.kernel.org Signed-off-by: Christian König <christian.koenig@amd.com> Link: https://patchwork.freedesktop.org/patch/msgid/20230821200201.24685-1-Philip.Yang@amd.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Limit the link rate to HBR3 or below (<=8.1Gbps) in SST mode.
UHBR (10Gbps+) link rates require 128b/132b channel encoding
which we have not yet hooked up into the SST/no-sideband codepaths.
The brute force iommu_flush_iotlb_all() was good enough for unmap, but
in some cases a map operation could require removing a table pte entry
to replace with a block entry. This also requires tlb invalidation.
Missing this was resulting an obscure iova fault on what should be a
valid buffer address.
Thanks to Robin Murphy for helping me understand the cause of the fault.
Cc: Robin Murphy <robin.murphy@arm.com> Cc: stable@vger.kernel.org Fixes: b145c6e65eb0 ("drm/msm: Add support to create a local pagetable") Signed-off-by: Rob Clark <robdclark@chromium.org>
Patchwork: https://patchwork.freedesktop.org/patch/578117/ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Few users have observed display corruption when they boot
the machine to KDE Plasma or playing games. We have root
caused the problem that whenever alloc_range() couldn't
find the required memory blocks the function was returning
SUCCESS in some of the corner cases.
The right approach would be if the total allocated size
is less than the required size, the function should
return -ENOSPC.
Nouveau manages GSP-RM DMA buffers with nvkm_gsp_mem objects. Several of
these buffers are never dealloced. Some of them can be deallocated
right after GSP-RM is initialized, but the rest need to stay until the
driver unloads.
Also futher bullet-proof these objects by poisoning the buffer and
clearing the nvkm_gsp_mem object when it is deallocated. Poisoning
the buffer should trigger an error (or crash) from GSP-RM if it tries
to access the buffer after we've deallocated it, because we were wrong
about when it is safe to deallocate.
Finally, change the mem->size field to a size_t because that's the same
type that dma_alloc_coherent expects.
Cc: <stable@vger.kernel.org> # v6.7 Fixes: 176fdcbddfd2 ("drm/nouveau/gsp/r535: add support for booting GSP-RM") Signed-off-by: Timur Tabi <ttabi@nvidia.com> Signed-off-by: Danilo Krummrich <dakr@redhat.com> Link: https://patchwork.freedesktop.org/patch/msgid/20240202230608.1981026-1-ttabi@nvidia.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
lock_task_sighand() can trigger a hard lockup. If NR_CPUS threads call
getrusage() at the same time and the process has NR_THREADS, spin_lock_irq
will spin with irqs disabled O(NR_CPUS * NR_THREADS) time.
Change getrusage() to use sig->stats_lock, it was specifically designed
for this type of use. This way it runs lockless in the likely case.
TODO:
- Change do_task_stat() to use sig->stats_lock too, then we can
remove spin_lock_irq(siglock) in wait_task_zombie().
- Turn sig->stats_lock into seqcount_rwlock_t, this way the
readers in the slow mode won't exclude each other. See
https://lore.kernel.org/all/20230913154907.GA26210@redhat.com/
- stats_lock has to disable irqs because ->siglock can be taken
in irq context, it would be very nice to change __exit_signal()
to avoid the siglock->stats_lock dependency.
Link: https://lkml.kernel.org/r/20240122155053.GA26214@redhat.com Signed-off-by: Oleg Nesterov <oleg@redhat.com> Reported-by: Dylan Hatch <dylanbhatch@google.com> Tested-by: Dylan Hatch <dylanbhatch@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Patch series "getrusage: use sig->stats_lock", v2.
This patch (of 2):
thread_group_cputime() does its own locking, we can safely shift
thread_group_cputime_adjusted() which does another for_each_thread loop
outside of ->siglock protected section.
This is also preparation for the next patch which changes getrusage() to
use stats_lock instead of siglock, thread_group_cputime() takes the same
lock. With the current implementation recursive read_seqbegin_or_lock()
is fine, thread_group_cputime() can't enter the slow mode if the caller
holds stats_lock, yet this looks more safe and better performance-wise.
The directory link count in eventfs was somewhat bogus. It was only being
updated when a directory child was being looked up and not on creation.
One solution would be to update in get_attr() the link count by iterating
the ei->children list and then adding 2. But that could slow down simple
stat() calls, especially if it's done on all directories in eventfs.
Another solution would be to add a parent pointer to the eventfs_inode
and keep track of the number of sub directories it has on creation. But
this adds overhead for something not really worthwhile.
The solution decided upon is to keep all directory links in eventfs as 1.
This tells user space not to rely on the hard links of directories. Which
in this case it shouldn't.
Link: https://lore.kernel.org/linux-trace-kernel/20240201002719.GS2087318@ZenIV/ Link: https://lore.kernel.org/linux-trace-kernel/20240201161617.339968298@goodmis.org Cc: stable@vger.kernel.org Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Ajay Kaher <ajay.kaher@broadcom.com> Fixes: c1504e510238 ("eventfs: Implement eventfs dir creation functions") Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The dentries and inodes are created when referenced in the lookup code.
There's no reason to call fsnotify_*() functions when they are created by
a reference. It doesn't make any sense.
Link: https://lore.kernel.org/linux-trace-kernel/20240201002719.GS2087318@ZenIV/ Link: https://lore.kernel.org/linux-trace-kernel/20240201161617.166973329@goodmis.org Cc: stable@vger.kernel.org Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Ajay Kaher <ajay.kaher@broadcom.com> Fixes: a376007917776 ("eventfs: Implement functions to create files and dirs when accessed"); Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There should never be a case where an evenfs_inode is being freed without
is_freed being set. Add a WARN_ON_ONCE() if it ever happens. That would
mean there was one too many put_ei()s.
Link: https://lore.kernel.org/linux-trace-kernel/20240201161616.843551963@goodmis.org Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Ajay Kaher <ajay.kaher@broadcom.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The eventfs inode had pointers to dentries (and child dentries) without
actually holding a refcount on said pointer. That is fundamentally
broken, and while eventfs tried to then maintain coherence with dentries
going away by hooking into the '.d_iput' callback, that doesn't actually
work since it's not ordered wrt lookups.
There were two reasonms why eventfs tried to keep a pointer to a dentry:
- the creation of a 'events' directory would actually have a stable
dentry pointer that it created with tracefs_start_creating().
And it needed that dentry when tearing it all down again in
eventfs_remove_events_dir().
This use is actually ok, because the special top-level events
directory dentries are actually stable, not just a temporary cache of
the eventfs data structures.
- the 'eventfs_inode' (aka ei) needs to stay around as long as there
are dentries that refer to it.
It then used these dentry pointers as a replacement for doing
reference counting: it would try to make sure that there was only
ever one dentry associated with an event_inode, and keep a child
dentry array around to see which dentries might still refer to the
parent ei.
This gets rid of the invalid dentry pointer use, and renames the one
valid case to a different name to make it clear that it's not just any
random dentry.
The magic child dentry array that is kind of a "reverse reference list"
is simply replaced by having child dentries take a ref to the ei. As
does the directory dentries. That makes the broken use case go away.
In order for the dentries to stay up-to-date with the eventfs changes,
just add a 'd_revalidate' function that checks the 'is_freed' bit.
Also, clean up the dentry release to actually use d_release() rather
than the slightly odd d_iput() function. We don't care about the inode,
all we want to do is to get rid of the refcount to the eventfs data
added by dentry->d_fsdata.
It would probably be cleaner to make eventfs its own filesystem, or at
least set its own dentry ops when looking up eventfs files. But as it
is, only eventfs dentries use d_fsdata, so we don't really need to split
these things up by use.
Another thing that might be worth doing is to make all eventfs lookups
mark their dentries as not worth caching. We could do that with
d_delete(), but the DCACHE_DONTCACHE flag would likely be even better.
As it is, the dentries are all freeable, but they only tend to get freed
at memory pressure rather than more proactively. But that's a separate
issue.
The dentry lookup for eventfs files was very broken, and had lots of
signs of the old situation where the filesystem names were all created
statically in the dentry tree, rather than being looked up dynamically
based on the eventfs data structures.
You could see it in the naming - how it claimed to "create" dentries
rather than just look up the dentries that were given it.
You could see it in various nonsensical and very incorrect operations,
like using "simple_lookup()" on the dentries that were passed in, which
only results in those dentries becoming negative dentries. Which meant
that any other lookup would possibly return ENOENT if it saw that
negative dentry before the data was then later filled in.
You could see it in the immense amount of nonsensical code that didn't
actually just do lookups.
The eventfs_find_events() code tries to walk up the tree to find the
event directory that a dentry belongs to, in order to then find the
eventfs inode that is associated with that event directory.
However, it uses an odd combination of walking the dentry parent,
looking up the eventfs inode associated with that, and then looking up
the dentry from there. Repeat.
But the code shouldn't have back-pointers to dentries in the first
place, and it should just walk the dentry parenthood chain directly.
Similarly, 'set_top_events_ownership()' looks up the dentry from the
eventfs inode, but the only reason it wants a dentry is to look up the
superblock in order to look up the root dentry.
But it already has the real filesystem inode, which has that same
superblock pointer. So just pass in the superblock pointer using the
information that's already there, instead of looking up extraneous data
that is irrelevant.
eventfs uses the tracefs_inode and assumes that it's already initialized
to zero. That is, it doesn't set fields to zero (like ti->private) after
getting its tracefs_inode. This causes bugs due to stale values.
Just initialize the entire structure to zero on allocation so there isn't
any more surprises.
This is a partial fix to access to ti->private. The assignment still needs
to be made before the dentry is instantiated.
Link: https://lore.kernel.org/linux-trace-kernel/20240131185512.315825944@goodmis.org Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Ajay Kaher <ajay.kaher@broadcom.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Fixes: 5790b1fb3d672 ("eventfs: Remove eventfs_file and just use eventfs_inode") Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202401291043.e62e89dc-oliver.sang@intel.com Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The eventfs inodes and directories are allocated when referenced. But this
leaves the issue of keeping consistent inode numbers and the number is
only saved in the inode structure itself. When the inode is no longer
referenced, it can be freed. When the file that the inode was representing
is referenced again, the inode is once again created, but the inode number
needs to be the same as it was before.
Just making the inode numbers the same for all files is fine, but that
does not work with directories. The find command will check for loops via
the inode number and having the same inode number for directories triggers:
# find /sys/kernel/tracing
find: File system loop detected;
'/sys/kernel/debug/tracing/events/initcall/initcall_finish' is part of the same file system loop as
'/sys/kernel/debug/tracing/events/initcall'.
[..]
Linus pointed out that the eventfs_inode structure ends with a single
32bit int, and on 64 bit machines, there's likely a 4 byte hole due to
alignment. We can use this hole to store the inode number for the
eventfs_inode. All directories in eventfs are represented by an
eventfs_inode and that data structure can hold its inode number.
That last int was also purposely placed at the end of the structure to
prevent holes from within. Now that there's a 4 byte number to hold the
inode, both the inode number and the last integer can be moved up in the
structure for better cache locality, where the llist and rcu fields can be
moved to the end as they are only used when the eventfs_inode is being
deleted.
As noted in the "Deprecated Interfaces, Language Features, Attributes,
and Conventions" documentation [1], size calculations (especially
multiplication) should not be performed in memory allocator (or similar)
function arguments due to the risk of them overflowing. This could lead
to values wrapping around and a smaller allocation being made than the
caller was expecting. Using those allocations could lead to linear
overflows of heap memory and other misbehaviors.
So, use the purpose specific kcalloc() function instead of the argument
size * count in the kzalloc() function.
The original eventfs code added a wrapper around the dcache_readdir open
callback and created all the dentries and inodes at open, and increment
their ref count. A wrapper was added around the dcache_readdir release
function to decrement all the ref counts of those created inodes and
dentries. But this proved to be buggy[1] for when a kprobe was created
during a dir read, it would create a dentry between the open and the
release, and because the release would decrement all ref counts of all
files and directories, that would include the kprobe directory that was
not there to have its ref count incremented in open. This would cause the
ref count to go to negative and later crash the kernel.
To solve this, the dentries and inodes that were created and had their ref
count upped in open needed to be saved. That list needed to be passed from
the open to the release, so that the release would only decrement the ref
counts of the entries that were incremented in the open.
Unfortunately, the dcache_readdir logic was already using the
file->private_data, which is the only field that can be used to pass
information from the open to the release. What was done was the eventfs
created another descriptor that had a void pointer to save the
dcache_readdir pointer, and it wrapped all the callbacks, so that it could
save the list of entries that had their ref counts incremented in the
open, and pass it to the release. The wrapped callbacks would just put
back the dcache_readdir pointer and call the functions it used so it could
still use its data[2].
But Linus had an issue with the "hijacking" of the file->private_data
(unfortunately this discussion was on a security list, so no public link).
Which we finally agreed on doing everything within the iterate_shared
callback and leave the dcache_readdir out of it[3]. All the information
needed for the getents() could be created then.
But this ended up being buggy too[4]. The iterate_shared callback was not
the right place to create the dentries and inodes. Even Christian Brauner
had issues with that[5].
An attempt was to go back to creating the inodes and dentries at
the open, create an array to store the information in the
file->private_data, and pass that information to the other callbacks.[6]
The difference between that and the original method, is that it does not
use dcache_readdir. It also does not up the ref counts of the dentries and
pass them. Instead, it creates an array of a structure that saves the
dentry's name and inode number. That information is used in the
iterate_shared callback, and the array is freed in the dir release. The
dentries and inodes created in the open are not used for the iterate_share
or release callbacks. Just their names and inode numbers.
Linus did not like that either[7] and just wanted to remove the dentries
being created in iterate_shared and use the hard coded inode numbers.
[ All this while Linus enjoyed an unexpected vacation during the merge
window due to lack of power. ]
The dentries and inodes are created in the readdir for the sole purpose of
getting a consistent inode number. Linus stated that is unnecessary, and
that all inodes can have the same inode number. For a virtual file system
they are pretty meaningless.
Instead use a single unique inode number for all files and one for all
directories.
As the ei->entries array is fixed for the duration of the eventfs_inode,
it can be used to skip over already read entries in eventfs_iterate().
That is, if ctx->pos is greater than zero, there's no reason in doing the
loop across the ei->entries array for the entries less than ctx->pos.
Instead, start the lookup of the entries at the current ctx->pos.
In order to apply a shortcut to skip over the current ctx->pos
immediately, by using the ei->entries array, the reading of that array
should be first. Moving the array reading before the linked list reading
will make the shortcut change diff nicer to read.
The ctx->pos was only updated when it added an entry, but the "skip to
current pos" check (c--) happened for every loop regardless of if the
entry was added or not. This inconsistency caused readdir to be incorrect.
It was due to:
for (i = 0; i < ei->nr_entries; i++) {
if (c > 0) {
c--;
continue;
}
mutex_lock(&eventfs_mutex);
/* If ei->is_freed then just bail here, nothing more to do */
if (ei->is_freed) {
mutex_unlock(&eventfs_mutex);
goto out;
}
r = entry->callback(name, &mode, &cdata, &fops);
mutex_unlock(&eventfs_mutex);
[..]
ctx->pos++;
}
But this can cause the iterator to return a file that was already read.
That's because of the way the callback() works. Some events may not have
all files, and the callback can return 0 to tell eventfs to skip the file
for this directory.
for instance, we have:
# ls /sys/kernel/tracing/events/ftrace/function
format hist hist_debug id inject
and
# ls /sys/kernel/tracing/events/sched/sched_switch/
enable filter format hist hist_debug id inject trigger
Where the function directory is missing "enable", "filter" and
"trigger". That's because the callback() for events has:
/*
* Only event directories that can be enabled should have
* triggers or filters, with the exception of the "print"
* event that can have a "trigger" file.
*/
if (!(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)) {
if (call->class->reg && strcmp(name, "enable") == 0) {
*mode = TRACE_MODE_WRITE;
*fops = &ftrace_enable_fops;
return 1;
}
Where the function event has the TRACE_EVENT_FL_IGNORE_ENABLE set.
This means that the entries array elements for "enable", "filter" and
"trigger" when called on the function event will have the callback return
0 and not 1, to tell eventfs to skip these files for it.
Because the "skip to current ctx->pos" check happened for all entries, but
the ctx->pos++ only happened to entries that exist, it would confuse the
reading of a directory. Which would cause:
# ls /sys/kernel/tracing/events/ftrace/function/
format hist hist hist_debug hist_debug id inject inject
The missing "enable", "filter" and "trigger" caused ls to show "hist",
"hist_debug" and "inject" twice.
Update the ctx->pos for every iteration to keep its update and the "skip"
update consistent. This also means that on error, the ctx->pos needs to be
decremented if it was incremented without adding something.
Link: https://lore.kernel.org/all/20240104150500.38b15a62@gandalf.local.home/ Link: https://lore.kernel.org/linux-trace-kernel/20240104220048.172295263@goodmis.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christian Brauner <brauner@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Fixes: 493ec81a8fb8e ("eventfs: Stop using dcache_readdir() for getdents()") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If ei->is_freed is set in eventfs_iterate(), it means that the directory
that is being iterated on is in the process of being freed. Just exit the
loop immediately when that is ever detected, and separate out the return
of the entry->callback() from ei->is_freed.
Link: https://lore.kernel.org/linux-trace-kernel/20240104220048.016261289@goodmis.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christian Brauner <brauner@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The eventfs creates dynamically allocated dentries and inodes. Using the
dcache_readdir() logic for its own directory lookups requires hiding the
cursor of the dcache logic and playing games to allow the dcache_readdir()
to still have access to the cursor while the eventfs saved what it created
and what it needs to release.
Instead, just have eventfs have its own iterate_shared callback function
that will fill in the dent entries. This simplifies the code quite a bit.
Link: https://lore.kernel.org/linux-trace-kernel/20240104015435.682218477@goodmis.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Ajay Kaher <akaher@vmware.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Christian Brauner <brauner@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The "lookup" parameter is a way to differentiate the call to
create_file/dir_dentry() from when it's just a lookup (no need to up the
dentry refcount) and accessed via a readdir (need to up the refcount).
But reality, it just makes the code more complex. Just up the refcount and
let the caller decide to dput() the result or not.
If the power domains are registered first with genpd and *after that*
the driver attempts to power them on in the probe sequence, then it is
possible that a race condition occurs if genpd tries to power them on
in the same time.
The same is valid for powering them off before unregistering them
from genpd.
Attempt to fix race conditions by first removing the domains from genpd
and *after that* powering down domains.
Also first power up the domains and *after that* register them
to genpd.
There are a ton of build errors when REGMAP is not set, so select
REGMAP to fix all of them.
Examples (not all of them):
../drivers/iio/imu/bno055/bno055_ser_core.c:495:15: error: variable 'bno055_ser_regmap_bus' has initializer but incomplete type
495 | static struct regmap_bus bno055_ser_regmap_bus = {
../drivers/iio/imu/bno055/bno055_ser_core.c:496:10: error: 'struct regmap_bus' has no member named 'write'
496 | .write = bno055_ser_write_reg,
../drivers/iio/imu/bno055/bno055_ser_core.c:497:10: error: 'struct regmap_bus' has no member named 'read'
497 | .read = bno055_ser_read_reg,
../drivers/iio/imu/bno055/bno055_ser_core.c: In function 'bno055_ser_probe':
../drivers/iio/imu/bno055/bno055_ser_core.c:532:18: error: implicit declaration of function 'devm_regmap_init'; did you mean 'vmem_map_init'? [-Werror=implicit-function-declaration]
532 | regmap = devm_regmap_init(&serdev->dev, &bno055_ser_regmap_bus,
../drivers/iio/imu/bno055/bno055_ser_core.c:532:16: warning: assignment to 'struct regmap *' from 'int' makes pointer from integer without a cast [-Wint-conversion]
532 | regmap = devm_regmap_init(&serdev->dev, &bno055_ser_regmap_bus,
../drivers/iio/imu/bno055/bno055_ser_core.c: At top level:
../drivers/iio/imu/bno055/bno055_ser_core.c:495:26: error: storage size of 'bno055_ser_regmap_bus' isn't known
495 | static struct regmap_bus bno055_ser_regmap_bus = {
Fixes: 2eef5a9cc643 ("iio: imu: add BNO055 serdev driver") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Andrea Merello <andrea.merello@iit.it> Cc: Jonathan Cameron <jic23@kernel.org> Cc: Lars-Peter Clausen <lars@metafoo.de> Cc: linux-iio@vger.kernel.org Cc: <Stable@vger.kernel.org> Link: https://lore.kernel.org/r/20240110185611.19723-1-rdunlap@infradead.org Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Aligning the buffer to the L1 cache is not sufficient in some platforms
as they might have larger cacheline sizes for caches after L1 and thus,
we can't guarantee DMA safety.
That was the whole reason to introduce IIO_DMA_MINALIGN in [1]. Do the same
for the sigma_delta ADCs.
Aligning the buffer to the L1 cache is not sufficient in some platforms
as they might have larger cacheline sizes for caches after L1 and thus,
we can't guarantee DMA safety.
That was the whole reason to introduce IIO_DMA_MINALIGN in [1]. Do the same
for the sigma_delta ADCs.
Fixes: 0fb6ee8d0b5e ("iio: ad_sigma_delta: Don't put SPI transfer buffer on the stack") Signed-off-by: Nuno Sa <nuno.sa@analog.com> Link: https://lore.kernel.org/r/20240117-dev_sigma_delta_no_irq_flags-v1-1-db39261592cf@analog.com Cc: <Stable@vger.kernel.org> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The kernel fails when compiling without `CONFIG_REGMAP_I2C` but with
`CONFIG_BMA400`.
```
ld: drivers/iio/accel/bma400_i2c.o: in function `bma400_i2c_probe':
bma400_i2c.c:(.text+0x23): undefined reference to `__devm_regmap_init_i2c'
```
Aligning the buffer to the L1 cache is not sufficient in some platforms
as they might have larger cacheline sizes for caches after L1 and thus,
we can't guarantee DMA safety.
That was the whole reason to introduce IIO_DMA_MINALIGN in [1]. Do the same
for st_sensors common buffer.
While at it, moved the odr_lock before buffer_data as we definitely
don't want any other data to share a cacheline with the buffer.
Recently, we encounter kernel crash in function rm3100_common_probe
caused by out of bound access of array rm3100_samp_rates (because of
underlying hardware failures). Add boundary check to prevent out of
bound access.
Fixes: 121354b2eceb ("iio: magnetometer: Add driver support for PNI RM3100") Suggested-by: Zhouyi Zhou <zhouzhouyi@gmail.com> Signed-off-by: zhili.liu <zhili.liu@ucas.com.cn> Link: https://lore.kernel.org/r/1704157631-3814-1-git-send-email-zhouzhouyi@gmail.com Cc: <Stable@vger.kernel.org> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 4c3577db3e4f ("Staging: iio: impedance-analyzer: Fix sparse
warning") fixed a compiler warning, but introduced a bug that resulted
in one of the two 16 bit IIO channels always being zero (when both are
enabled).
This is because int is 32 bits wide on most architectures and in the
case of a little-endian machine the two most significant bytes would
occupy the buffer for the second channel as 'val' is being passed as a
void pointer to 'iio_push_to_buffers()'.
Fix by defining 'val' as u16. Tested working on ARM64.
The commit allowed workqueue_apply_unbound_cpumask() to clear __WQ_ORDERED
on now removed implicitly ordered workqueues. This was incorrect in that
system-wide config change shouldn't break ordering properties of all
workqueues. The reason why apply_workqueue_attrs() path was allowed to do so
was because it was targeting the specific workqueue - either the workqueue
had WQ_SYSFS set or the workqueue user specifically tried to change
max_active, both of which indicate that the workqueue doesn't need to be
ordered.
The implicitly ordered workqueue promotion was removed by the previous
commit 3bc1e711c26b ("workqueue: Don't implicitly make UNBOUND workqueues w/
@max_active==1 ordered"). However, it didn't update this path and broke
build. Let's revert the commit which was incorrect in the first place which
also fixes build.
Fix to search a field from the structure which has anonymous union
correctly.
Since the reference `type` pointer was updated in the loop, the search
loop suddenly aborted where it hits an anonymous union. Thus it can not
find the field after the anonymous union. This avoids updating the
cursor `type` pointer in the loop.
Since the BTF type setting updates probe_arg::type, the type size
calculation and setting print-fmt should be done after that.
Without this fix, the argument size and print-fmt can be wrong.
Fix to show a parse error for bad type (non-string) for $comm/$COMM and
immediate-string. With this fix, error_log file shows appropriate error
message as below.
[ 30.144183] trace_kprobe: error: $comm and immediate-string only accepts string type
Command: p vfs_read $comm:u32
^
[ 62.618500] trace_kprobe: error: $comm and immediate-string only accepts string type
Command: p vfs_read \"hoge":u32
^ Link: https://lore.kernel.org/all/170602215411.215583.2238016352271091852.stgit@devnote2/ Fixes: 3dd1f7f24f8c ("tracing: probeevent: Fix to make the type of $comm string") Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix trace_string() by assigning the string length to the return variable
which got lost in commit ddeea494a16f ("tracing/synthetic: Use union
instead of casts") and caused trace_string() to always return 0.
Link: https://lore.kernel.org/linux-trace-kernel/20240214220555.711598-1-thorsten.blum@toblux.com Cc: stable@vger.kernel.org Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Fixes: ddeea494a16f ("tracing/synthetic: Use union instead of casts") Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
While looking at improving the saved_cmdlines cache I found a huge amount
of wasted memory that should be used for the cmdlines.
The tracing data saves pids during the trace. At sched switch, if a trace
occurred, it will save the comm of the task that did the trace. This is
saved in a "cache" that maps pids to comms and exposed to user space via
the /sys/kernel/tracing/saved_cmdlines file. Currently it only caches by
default 128 comms.
The structure that uses this creates an array to store the pids using
PID_MAX_DEFAULT (which is usually set to 32768). This causes the structure
to be of the size of 131104 bytes on 64 bit machines.
In hex: 131104 = 0x20020, and since the kernel allocates generic memory in
powers of two, the kernel would allocate 0x40000 or 262144 bytes to store
this structure. That leaves 131040 bytes of wasted space.
Worse, the structure points to an allocated array to store the comm names,
which is 16 bytes times the amount of names to save (currently 128), which
is 2048 bytes. Instead of allocating a separate array, make the structure
end with a variable length string and use the extra space for that.
This is similar to a recommendation that Linus had made about eventfs_inode names:
Instead of allocating a separate string array to hold the saved comms,
have the structure end with: char saved_cmdlines[]; and round up to the
next power of two over sizeof(struct saved_cmdline_buffers) + num_cmdlines * TASK_COMM_LEN
It will use this extra space for the saved_cmdline portion.
Now, instead of saving only 128 comms by default, by using this wasted
space at the end of the structure it can save over 8000 comms and even
saves space by removing the need for allocating the other array.
Link: https://lore.kernel.org/linux-trace-kernel/20240209063622.1f7b6d5f@rorschach.local.home Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Vincent Donnefort <vdonnefort@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Mete Durlu <meted@linux.ibm.com> Fixes: 939c7a4f04fcd ("tracing: Introduce saved_cmdlines_size file") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, the timerlat's hrtimer is initialized at the first read of
timerlat_fd, and destroyed at close(). It works, but it causes an error
if the user program open() and close() the file without reading.
After updating bb_free in mb_free_blocks, it is possible to return without
updating bb_fragments because the block being freed is found to have
already been freed, which leads to inconsistency between bb_free and
bb_fragments.
Since the group may be unlocked in ext4_grp_locked_error(), this can lead
to problems such as dividing by zero when calculating the average fragment
length. Hence move the update of bb_free to after the block double-free
check guarantees that the corresponding statistics are updated only after
the core block bitmap is modified.
Fixes: eabe0444df90 ("ext4: speed-up releasing blocks on commit") CC: <stable@vger.kernel.org> # 3.10 Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20240104142040.2835097-5-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In ext4_move_extents(), moved_len is only updated when all moves are
successfully executed, and only discards orig_inode and donor_inode
preallocations when moved_len is not zero. When the loop fails to exit
after successfully moving some extents, moved_len is not updated and
remains at 0, so it does not discard the preallocations.
If the moved extents overlap with the preallocated extents, the
overlapped extents are freed twice in ext4_mb_release_inode_pa() and
ext4_process_freed_data() (as described in commit 94d7c16cbbbd ("ext4:
Fix double-free of blocks with EXT4_IOC_MOVE_EXT")), and bb_free is
incremented twice. Hence when trim is executed, a zero-division bug is
triggered in mb_update_avg_fragment_size() because bb_free is not zero
and bb_fragments is zero.
Therefore, update move_len after each extent move to avoid the issue.
Reported-by: Wei Chen <harperchen1110@gmail.com> Reported-by: xingwei lee <xrivendell7@gmail.com> Closes: https://lore.kernel.org/r/CAO4mrferzqBUnCag8R3m2zf897ts9UEuhjFQGPtODT92rYyR2Q@mail.gmail.com Fixes: fcf6b1b729bc ("ext4: refactor ext4_move_extents code base") CC: <stable@vger.kernel.org> # 3.18 Signed-off-by: Baokun Li <libaokun1@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20240104142040.2835097-2-libaokun1@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In remoteproc shutdown sequence, rpmsg_remove will get called which
would depopulate all the child nodes that have been created during
rpmsg_probe. This would result in cb_remove call for all the context
banks for the remoteproc. In cb_remove function, session 0 is
getting skipped which is not correct as session 0 will never become
available again. Add changes to mark session 0 also as invalid.
In (e)poll mode, threads often depend on I/O events to determine when
data is ready for consumption. Within binder, a thread may initiate a
command via BINDER_WRITE_READ without a read buffer and then make use
of epoll_wait() or similar to consume any responses afterwards.
It is then crucial that epoll threads are signaled via wakeup when they
queue their own work. Otherwise, they risk waiting indefinitely for an
event leaving their work unhandled. What is worse, subsequent commands
won't trigger a wakeup either as the thread has pending work.
Customer has reported an issue with specific desktop platform
where two CS42L42 codecs are connected to CS8409 HDA bridge.
If "Master Volume Control" is created then on Ubuntu OS UCM
left/right balance slider in UI audio settings has no effect.
This patch will fix this issue for a target paltform.
WCD938x sound codec driver ignores return status of getting regulators
and returns EINVAL instead of EPROBE_DEFER. If regulator provider
probes after the codec, system is left without probed audio:
wcd938x_codec audio-codec: wcd938x_probe: Fail to obtain platform data
wcd938x_codec: probe of audio-codec failed with error -22
Fixes: 16572522aece ("ASoC: codecs: wcd938x-sdw: add SoundWire driver") Cc: <stable@vger.kernel.org> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Link: https://msgid.link/r/20240117151208.1219755-1-krzysztof.kozlowski@linaro.org Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
After the linked LLVM change, building ARCH=um defconfig results in a
segmentation fault in modpost. Prior to commit a23e7584ecf3 ("modpost:
unify 'sym' and 'to' in default_mismatch_handler()"), there was a
warning:
WARNING: modpost: vmlinux.o(__ex_table+0x88): Section mismatch in reference to the .ltext:(unknown)
WARNING: modpost: The relocation at __ex_table+0x88 references
section ".ltext" which is not in the list of
authorized sections. If you're adding a new section
and/or if this reference is valid, add ".ltext" to the
list of authorized sections to jump to on fault.
This can be achieved by adding ".ltext" to
OTHER_TEXT_SECTIONS in scripts/mod/modpost.c.
The linked LLVM change moves global objects to the '.ltext' (and
'.ltext.*' with '-ffunction-sections') sections with '-mcmodel=large',
which ARCH=um uses. These sections should be handled just as '.text'
and '.text.*' are, so add them to TEXT_SECTIONS.
The kernel builds with -fno-PIE, so commit 883354afbc10 ("um: link
vmlinux with -no-pie") added the compiler linker flag '-no-pie' via
cc-option because '-no-pie' was only supported in GCC 6.1.0 and newer.
While this works for GCC, this does not work for clang because cc-option
uses '-c', which stops the pipeline right before linking, so '-no-pie'
is unconsumed and clang warns, causing cc-option to fail just as it
would if the option was entirely unsupported:
$ clang -Werror -no-pie -c -o /dev/null -x c /dev/null
clang-16: error: argument unused during compilation: '-no-pie' [-Werror,-Wunused-command-line-argument]
A recent version of clang exposes this because it generates a relocation
under '-mcmodel=large' that is not supported in PIE mode:
/usr/sbin/ld: init/main.o: relocation R_X86_64_32 against symbol `saved_command_line' can not be used when making a PIE object; recompile with -fPIE
/usr/sbin/ld: failed to set dynamic section sizes: bad value
clang: error: linker command failed with exit code 1 (use -v to see invocation)
Remove the cc-option check altogether. It is wasteful to invoke the
compiler to check for '-no-pie' because only one supported compiler
version does not support it, GCC 5.x (as it is supported with the
minimum version of clang and GCC 6.1.0+). Use a combination of the
gcc-min-version macro and CONFIG_CC_IS_CLANG to unconditionally add
'-no-pie' with CONFIG_LD_SCRIPT_DYN=y, so that it is enabled with all
compilers that support this. Furthermore, using gcc-min-version can help
turn this back into
LINK-$(CONFIG_LD_SCRIPT_DYN) += -no-pie
when the minimum version of GCC is bumped past 6.1.0.
Invoking the make_tx_response() / push_tx_responses() pair with no lock
held would be acceptable only if all such invocations happened from the
same context (NAPI instance or dealloc thread). Since this isn't the
case, and since the interface "spec" also doesn't demand that multicast
operations may only be performed with no in-flight transmits,
MCAST_{ADD,DEL} processing also needs to acquire the response lock
around the invocations.
To prevent similar mistakes going forward, "downgrade" the present
functions to private helpers of just the two remaining ones using them
directly, with no forward declarations anymore. This involves renaming
what so far was make_tx_response(), for the new function of that name
to serve the new (wrapper) purpose.
While there,
- constify the txp parameters,
- correct xenvif_idx_release()'s status parameter's type,
- rename {,_}make_tx_response()'s status parameters for consistency with
xenvif_idx_release()'s.
Fixes: 210c34dcd8d9 ("xen-netback: add support for multicast control") Cc: stable@vger.kernel.org Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Paul Durrant <paul@xen.org> Link: https://lore.kernel.org/r/980c6c3d-e10e-4459-8565-e8fbde122f00@suse.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When using hotplug and bringing up a 32-bit CPU, ask the firmware about the
BTLB information to set up the static (block) TLB entries.
For that write access to the static btlb_info struct is needed, but
since it is marked __ro_after_init the kernel segfaults with missing
write permissions.
Fix the crash by dropping the __ro_after_init annotation.
The current exception handler implementation, which assists when accessing
user space memory, may exhibit random data corruption if the compiler decides
to use a different register than the specified register %r29 (defined in
ASM_EXCEPTIONTABLE_REG) for the error code. If the compiler choose another
register, the fault handler will nevertheless store -EFAULT into %r29 and thus
trash whatever this register is used for.
Looking at the assembly I found that this happens sometimes in emulate_ldd().
To solve the issue, the easiest solution would be if it somehow is
possible to tell the fault handler which register is used to hold the error
code. Using %0 or %1 in the inline assembly is not posssible as it will show
up as e.g. %r29 (with the "%r" prefix), which the GNU assembler can not
convert to an integer.
This patch takes another, better and more flexible approach:
We extend the __ex_table (which is out of the execution path) by one 32-word.
In this word we tell the compiler to insert the assembler instruction
"or %r0,%r0,%reg", where %reg references the register which the compiler
choosed for the error return code.
In case of an access failure, the fault handler finds the __ex_table entry and
can examine the opcode. The used register is encoded in the lowest 5 bits, and
the fault handler can then store -EFAULT into this register.
Since we extend the __ex_table to 3 words we can't use the BUILDTIME_TABLE_SORT
config option any longer.
Syzkaller reported [1] hitting a warning after failing to allocate
resources for skb in hsr_init_skb(). Since a WARN_ONCE() call will
not help much in this case, it might be prudent to switch to
netdev_warn_once(). At the very least it will suppress syzkaller
reports such as [1].
Just in case, use netdev_warn_once() in send_prp_supervision_frame()
for similar reasons.
rx_data_reassembly skb is stored during NCI data exchange for processing
fragmented packets. It is dropped only when the last fragment is processed
or when an NTF packet with NCI_OP_RF_DEACTIVATE_NTF opcode is received.
However, the NCI device may be deallocated before that which leads to skb
leak.
As by design the rx_data_reassembly skb is bound to the NCI device and
nothing prevents the device to be freed before the skb is processed in
some way and cleaned, free it on the NCI device cleanup.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Fixes: 6a2968aaf50c ("NFC: basic NCI protocol implementation") Cc: stable@vger.kernel.org Reported-by: syzbot+6b7c68d9c21e4ee4251b@syzkaller.appspotmail.com Closes: https://lore.kernel.org/lkml/000000000000f43987060043da7b@google.com/ Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 90ceddcb4950 ("bpf: Support llvm-objcopy for vmlinux BTF")
changed the ELF type of .btf.vmlinux.bin.o to ET_REL via dd, which works
fine for little endian platforms:
While in the area, update the comment to mention that binutils 2.35+
matches LLD's behavior of rejecting an ET_EXEC input, which occurred
after the comment was added.
There currently exists two thinkpad headset jack fixups:
ALC285_FIXUP_THINKPAD_NO_BASS_SPK_HEADSET_JACK
ALC285_FIXUP_THINKPAD_HEADSET_JACK
The latter is applied to alc285 and alc287 thinkpads which contain
bass speakers.
However, the former was only being applied to alc285 thinkpads,
leaving non-bass alc287 thinkpads with no headset button controls.
This patch fixes that by adding ALC285_FIXUP_THINKPAD_NO_BASS_SPK_HEADSET_JACK
to the alc287 chains, allowing the detection of headset buttons.
The inode_getsecctx LSM hook has previously been corrected to have
-EOPNOTSUPP instead of 0 as the default return value to fix BPF LSM
behavior. However, the call_int_hook()-generated loop in
security_inode_getsecctx() was left treating 0 as the neutral value, so
after an LSM returns 0, the loop continues to try other LSMs, and if one
of them returns a non-zero value, the function immediately returns with
said value. So in a situation where SELinux and the BPF LSMs registered
this hook, -EOPNOTSUPP would be incorrectly returned whenever SELinux
returned 0.
Fix this by open-coding the call_int_hook() loop and making it use the
correct LSM_RET_DEFAULT() value as the neutral one, similar to what
other hooks do.
For these hooks the true "neutral" value is -EOPNOTSUPP, which is
currently what is returned when no LSM provides this hook and what LSMs
return when there is no security context set on the socket. Correct the
value in <linux/lsm_hooks.h> and adjust the dispatch functions in
security/security.c to avoid issues when the BPF LSM is enabled.
Cc: stable@vger.kernel.org Fixes: 98e828a0650f ("security: Refactor declaration of LSM hooks") Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
[PM: subject line tweak] Signed-off-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[why]
MAX_SURFACES is per stream, while MAX_PLANES is per asic. The
mpc_combine is an array that records all the planes per asic. Therefore
MAX_PLANES should be used as the array size. Using MAX_SURFACES causes
array overflow when there are more than 3 planes.
[how]
Use the MAX_PLANES for the mpc_combine array size.
Cc: Mario Limonciello <mario.limonciello@amd.com> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: stable@vger.kernel.org Reviewed-by: Rodrigo Siqueira <rodrigo.siqueira@amd.com> Reviewed-by: Nevenko Stupar <nevenko.stupar@amd.com> Reviewed-by: Chaitanya Dhere <chaitanya.dhere@amd.com> Acked-by: Tom Chung <chiahsuan.chung@amd.com> Signed-off-by: Wenjing Liu <wenjing.liu@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>
Allows us to detect subsequent IH ring buffer overflows as well.
Cc: Joshua Ashton <joshua@froggi.es> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: Christian König <christian.koenig@amd.com> Cc: stable@vger.kernel.org Signed-off-by: Friedrich Vock <friedrich.vock@gmx.de> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
projects / thirdparty / kernel / stable.git / log
