While fuzzing with Syzkaller, a persistent `schedule_timeout: wrong
timeout value` warning was observed, accompanied by SMBus controller
state machine corruption.
The I2C_TIMEOUT ioctl accepts a user-provided timeout in multiples of
10 ms. The user argument is checked against INT_MAX, but it is
subsequently multiplied by 10 before being passed to msecs_to_jiffies().
A malicious user can pass a large value (e.g., 429496729) that passes
the `arg > INT_MAX` check but overflows when multiplied by 10. This
results in a truncated 32-bit unsigned value that bypasses the
internal `(int)m < 0` check in `msecs_to_jiffies()`.
The truncated value is then assigned to `client->adapter->timeout`
(a signed 32-bit int), which is reinterpreted as a negative number.
When passed to wait_for_completion_timeout(), this negative value
undergoes sign extension to a 64-bit unsigned long, triggering the
`schedule_timeout` warning and causing premature returns. This leaves
the SMBus state machine in an unrecoverable state, constituting a
local Denial of Service (DoS).
Fix this by bounding the user argument to `INT_MAX / 10`.
Signed-off-by: Mingyu Wang <25181214217@stu.xidian.edu.cn>
[wsa: move the comment as well]
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
The ELAN0678 touchpad (04F3:3195) found in the Lenovo ThinkPad X13
exhibits excessive smoothing when the I2C bus runs at 400KHz, making
the touchpad feel sluggish when plugged into AC power. This is the
same issue previously fixed for ELAN06FA.
The device's ACPI table (Lenovo TP-R22) specifies 0x00061A80 (400KHz)
for the I2cSerialBusV2 descriptor. Forcing the bus to 100KHz eliminates
the sluggish behavior.
Signed-off-by: Niels Franke <nielsfranke@gmail.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
[wsa: kept the sorting]
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
dlfb_ops_mmap() uses remap_pfn_range() to map vmalloc framebuffer pages
to userspace but sets no vm_ops on the VMA. This means the kernel cannot
track active mmaps. When dlfb_realloc_framebuffer() replaces the backing
buffer via FBIOPUT_VSCREENINFO, existing mmap PTEs are not invalidated.
On USB disconnect, dlfb_ops_destroy() calls vfree() on the old pages
while userspace PTEs still reference them, resulting in a use-after-free:
the process retains read/write access to freed kernel pages.
Add vm_operations_struct with open/close callbacks that maintain an
atomic mmap_count on struct dlfb_data. In dlfb_realloc_framebuffer(),
check mmap_count and return -EBUSY if the buffer is currently mapped,
preventing buffer replacement while userspace holds stale PTEs.
Tested with PoC using dummy_hcd + raw_gadget USB device emulation.
Signed-off-by: Rajat Gupta <rajgupt@qti.qualcomm.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable@vger.kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>
The i2c block on the Apple silicon t8122 (M3) SoC is compatible with the
existing driver. Add "apple,t8122-i2c" as SoC specific compatible under
"apple,t8103-i2c" used by the deriver.
Signed-off-by: Janne Grunau <j@jannau.net>
Acked-by: Andi Shyti <andi.shyti@kernel.org>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Bitwise OR | operator has a higher precedence than the ternary ?:
operatior. It will be incorrectly evaluated as:
new->data[1] |= (FIELD_PREP(...) | dev_data->ats_enabled) ? DTE_FLAG_IOTLB : 0;
Wrap the conditional operation in parentheses to enforce the
correct evaluation order.
Fixes: 93eee2a49c ("iommu/amd: Refactor logic to program the host page table in DTE")
Signed-off-by: Weinan Liu <wnliu@google.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Vasant Hegde <vasant.hegde@amd.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Currently, the driver may repeatedly call reinit_completion() during
transfer which contains multiple messages, while another thread is
waiting for the completion.
This happens during transfer with more than 1 message, invoked via
stm32f7_i2c_xfer_core() -> stm32f7_i2c_xfer_msg(). After invoking the
stm32f7_i2c_xfer_msg() to start transfer, stm32f7_i2c_xfer_core()
calls wait_for_completion_timeout() to wait for completion of the
transfer of all messages. When the first message transfer completes,
the hard IRQ handler triggers, and detects transfer completion, which
leads to stm32f7_i2c_isr_event_thread() IRQ thread being started. The
stm32f7_i2c_isr_event_thread() calls stm32f7_i2c_xfer_msg() in case
there are more messages.
Without this change, the second and later stm32f7_i2c_xfer_msg() would
call reinit_completion() on the completion which is still being waited
for in stm32f7_i2c_xfer_core(). Fix this by moving the reinit_completion()
into stm32f7_i2c_xfer_core(), together with wait_for_completion_timeout().
Since stm32f7_i2c_xfer_core() now waits for completion of the entire
transfer, increase the default timeout. This fixes sporadic transfer
timeouts on STM32MP25xx during kernel boot.
Fixes: aeb068c572 ("i2c: i2c-stm32f7: add driver")
Signed-off-by: Marek Vasut <marex@nabladev.com>
[wsa: reworded commit subject]
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Add the T7 SOC compatible which fallback to AXG compatible.
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Ronald Claveau <linux-kernel-dev@aliel.fr>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Currently the code enqueue work items using {queue|mod}_delayed_work(),
using system_long_wq. This workqueue should be used when long works are
expected, but it is a per-cpu workqueue.
This is important because queue_delayed_work() queue the work using:
queue_delayed_work_on(WORK_CPU_UNBOUND, ...);
Note that WORK_CPU_UNBOUND = NR_CPUS.
This would end up calling __queue_delayed_work() that does:
if (housekeeping_enabled(HK_TYPE_TIMER)) {
// [....]
} else {
if (likely(cpu == WORK_CPU_UNBOUND))
add_timer_global(timer);
else
add_timer_on(timer, cpu);
}
So when cpu == WORK_CPU_UNBOUND the timer is global and is
not using a specific CPU. Later, when __queue_work() is called:
if (req_cpu == WORK_CPU_UNBOUND) {
if (wq->flags & WQ_UNBOUND)
cpu = wq_select_unbound_cpu(raw_smp_processor_id());
else
cpu = raw_smp_processor_id();
}
Because the wq is not unbound, it takes the CPU where the timer
fired and enqueue the work on that CPU.
The consequence of all of this is that the work can run anywhere,
depending on where the timer fired.
Recently, a new unbound workqueue specific for long running work has
been added:
c116737e97 ("workqueue: Add system_dfl_long_wq for long unbound works")
So change system_long_wq with system_dfl_long_wq so that the work may
benefit from scheduler task placement.
Signed-off-by: Marco Crivellari <marco.crivellari@suse.com>
[wsa: remove FIXME as well]
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
The HT check now only applies in strict mode since APs
were found to be broken. Mark it as such.
Fixes: 711a9c018a ("wifi: mac80211: skip ieee80211_verify_sta_ht_mcs_support check in non-strict mode")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Recursive eventfd wakeups must defer io_uring eventfd signaling because
eventfd_signal_mask() rejects reentry from eventfd wakeup handlers. The
io_ev_fd ops bit tracks an outstanding deferred signal so that the same
rcu_head is not queued twice.
That bit is only set today. Once the first deferred callback runs, later
recursive notifications still see the bit set and skip queueing another
deferred signal. This can leave new completions without a matching
eventfd wake after the first recursive deferral.
Clear the pending bit before issuing the deferred signal. If the wakeup
path recurses while the callback runs, a new signal can be queued for
the next RCU grace period while the current callback keeps its reference
until it returns.
Signed-off-by: Yufan Chen <ericterminal@gmail.com>
Fixes: 60b6c075e8 ("io_uring/eventfd: move to more idiomatic RCU free usage")
Link: https://patch.msgid.link/20260503175710.37209-1-yufan.chen@linux.dev
Signed-off-by: Jens Axboe <axboe@kernel.dk>
IORING_UNREGISTER_NAPI disables NAPI busy polling, but it currently
leaves any previously tracked NAPI IDs on the ring context. The normal
wait path only checks whether the list is empty before entering the busy
poll helper, so an unregistered ring can still observe stale entries and
run an unexpected busy poll pass.
Make unregister switch the context to inactive and free the tracked
entries. Do the same inactive transition while changing the tracking
strategy, and recheck the expected tracking mode under napi_lock before
inserting a newly learned NAPI ID. This prevents a racing poll path from
repopulating the list after unregister or reconfiguration.
Also make the busy poll dispatcher ignore inactive mode explicitly.
Signed-off-by: Yufan Chen <ericterminal@gmail.com>
Fixes: 6bf90bd8c5 ("io_uring/napi: add static napi tracking strategy")
Link: https://patch.msgid.link/20260503175610.35521-1-yufan.chen@linux.dev
Signed-off-by: Jens Axboe <axboe@kernel.dk>
TTM pool shrinking frees pages by calling __free_pages() directly,
which bypasses updates to NR_GPU_ACTIVE and leaves GPU MM accounting
out of sync.
Introduce a helper, __free_pages_gpu_account(), and use it for all page
frees in ttm_pool.c so GPU MM statistics are updated consistently.
Reported-by: Kenneth Crudup <kenny@panix.com>
Fixes: ae80122f38 ("drm/ttm: use gpu mm stats to track gpu memory allocations. (v4)")
Cc: Christian Koenig <christian.koenig@amd.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: David Airlie <airlied@gmail.com>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Tested-by: Kenneth Crudup <kenny@panix.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Link: https://patch.msgid.link/20260502065338.2720646-1-matthew.brost@intel.com
Commit 62e7dd0a39 ("smb: common: change the data type of num_aces
to le16") split struct smb_acl's __le32 num_aces field into __le16
num_aces and __le16 reserved. The reserved field corresponds to Sbz2
in the MS-DTYP ACL wire format, which must be zero [1].
When building an ACL descriptor in build_sec_desc(), we are using a
kmalloc()'ed descriptor buffer and writing the fields explicitly using
le16() writes now. This never writes to the 2 byte reserved field,
leaving it as uninitialized heap data.
When the reserved field happens to contain non-zero slab garbage,
Samba rejects the security descriptor with "ndr_pull_security_descriptor
failed: Range Error", causing chmod to fail with EINVAL.
Change kmalloc() to kzalloc() to ensure the entire buffer is
zero-initialized.
Fixes: 62e7dd0a39 ("smb: common: change the data type of num_aces to le16")
Cc: stable@vger.kernel.org
Signed-off-by: Bjoern Doebel <doebel@amazon.de>
Assisted-by: Kiro:claude-opus-4.6
[1] https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-dtyp/20233ed8-a6c6-4097-aafa-dd545ed24428
Signed-off-by: Steve French <stfrench@microsoft.com>
It is possible that SMB2_open_init may not set lease context based
on the requested oplock level. This can happen when leases have been
temporarily or permanently disabled. When this happens, we will have
open_cached_dir making an open without lease context and the response
will anyway be rejected by open_cached_dir (thereby forcing a close to
discard this open). That's unnecessary two round-trips to the server.
This change adds a check before making the open request to the server
to make sure that SMB2_open_init did add the expected lease context
to the open in open_cached_dir.
Cc: <stable@vger.kernel.org>
Reviewed-by: Bharath SM <bharathsm@microsoft.com>
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
When timer interrupt arrives in guest kernel, guest kernel clears the
timer interrupt and program timer with the next incoming event.
During this stage, timer tick is -1 and timer interrupt status is
disabled in ESTAT register. KVM hypervisor need write zero with timer
tick register and wait timer interrupt injection from HW side, and
then clear timer interrupt.
So there is 2 cycle delay in KVM hypervisor to emulate such scenery,
and the delay is unnecessary if there is no need to clear the timer
interrupt.
Here move 2 cycle delay into timer clear scenery and add timer ESTAT
checking after delay, and set max timer expire value if timer interrupt
does not arrive still.
Cc: stable@vger.kernel.org
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
With passthrough HW timer, timer interrupt is injected by HW. When
inject emulated CPU interrupt by software such SIP0/SIP1/IPI, HW timer
interrupt may be lost.
Here check whether there is timer tick value inversion before and after
injecting emulated CPU interrupt by software, timer enabling by reading
timer cfg register is skipped. If the timer tick value is detected with
changing, then timer should be enabled. And inject a timer interrupt by
software if there is.
Cc: <stable@vger.kernel.org>
Fixes: f45ad5b8aa ("LoongArch: KVM: Implement vcpu interrupt operations").
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
When AVEC interrupt controller is emulated in user space, AVEC interrupt
is injected by software like SIP0/SIP1/TI/IPI interrupts. Here also move
the AVEC interrupt injection in switch loop.
Cc: stable@vger.kernel.org
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
kvm_flush_pte() is the only caller that directly assigns *pte instead
of using the kvm_set_pte() wrapper. Use the wrapper for consistency with
the rest of the file.
No functional change intended.
Cc: stable@vger.kernel.org
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Tao Cui <cuitao@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
In the ldptr (0x24...0x27) opcode decoding path, the default case only
breaks out but without setting "ret" value to EMULATE_FAIL. This leaves
run->mmio.len uninitialized (stale from a previous MMIO operation) while
"ret" value remains EMULATE_DO_MMIO, causing the code to proceed with an
incorrect MMIO length.
Add "ret = EMULATE_FAIL" to match the other default branches in the same
function (e.g. the 0x28...0x2e and 0x38 cases).
Cc: stable@vger.kernel.org
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Tao Cui <cuitao@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
It doesn't make sense to return the recommended maximum number of vCPUs
which exceeds the maximum possible number of vCPUs.
Other architectures have already done this, such as commit 57a2e13ebd
("KVM: MIPS: Cap KVM_CAP_NR_VCPUS by KVM_CAP_MAX_VCPUS")
Cc: stable@vger.kernel.org
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Qiang Ma <maqianga@uniontech.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Insert the appropriate UNWIND hint into the kvm_exc_entry assembly
function to guide the generation of correct ORC table entries, thereby
solving the timeout problem ("unreliable stack") while loading the
livepatch-sample module on a physical machine running virtual machines
with multiple vcpus.
Cc: stable@vger.kernel.org
Signed-off-by: Xianglai Li <lixianglai@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
If we directly compile the switch.S file into the kernel, the address of
the kvm_exc_entry function will definitely be within the DMW memory area.
Therefore, we will no longer need to perform a copy relocation of the
kvm_exc_entry.
So this patch compiles switch.S directly into the kernel, and then remove
the copy relocation execution logic for the kvm_exc_entry function.
Cc: stable@vger.kernel.org
Signed-off-by: Xianglai Li <lixianglai@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
The custom definition is identical to the generic fallback one.
So remove it.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
When firmware enables 64-bit PCI host bridge support, some root bridges
already provide valid 64-bit mem resource windows through ACPI.
In this case, the LoongArch-specific mem resource high-bits fixup in
acpi_prepare_root_resources() should not be applied unconditionally.
Otherwise, the kernel may override the native resource layout derived
from firmware, and later BAR assignment can fail to place device BARs
into the intended 64-bit address space correctly.
Add a per-root-bridge ACPI flag, PCIH, and evaluate it from the current
root bridge device scope. When PCIH is set, skip the mem resource high-
bits fixup path and let the kernel use the firmware-provided resource
description directly. When PCIH is absent or cleared, keep the existing
behavior and continue filling the high address bits from the host bridge
address.
This makes the behavior per-root-bridge configurable and avoids breaking
valid 64-bit BAR space allocation on bridges whose 64-bit windows have
already been fully described by firmware.
Cc: stable@vger.kernel.org
Suggested-by: Chao Li <lichao@loongson.cn>
Tested-by: Dongyan Qian <qiandongyan@loongson.cn>
Signed-off-by: Dongyan Qian <qiandongyan@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
The SYM_SIGFUNC_START definition should match sigcontext that the length
of GPRs are 8 bytes for both 32BIT and 64BIT. So replace SZREG with 8 to
fix it.
Cc: stable@vger.kernel.org
Fixes: e4878c37f6 ("LoongArch: vDSO: Emit GNU_EH_FRAME correctly")
Suggested-by: Xi Ruoyao <xry111@xry111.site>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Clang/LLVM build needs -m32/-m64 to switch triple variants (i.e. the
--target=xxx parameter). Otherwise we get build errors for CONFIG_32BIT.
GCC doesn't support -m32/-m64 now, but maybe support in future, so use
cc-option to specify them.
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202604232041.ESJDwVG4-lkp@intel.com/
Suggested-by: Nathan Chancellor <nathan@kernel.org
Tested-by: WANG Rui <wangrui@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
CONFIG_64BIT is the mandatory option before v7.0, but in v7.1-rc1 both
CONFIG_32BIT and CONFIG_64BIT are selectable and CONFIG_32BIT became the
default option. This breaks existing configurations, so explicitly make
CONFIG_64BIT as the default option to keep existing behavior.
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
* Check that nEPT/nNPT is enabled in slow flush hypercalls. If it is
not, the hypercalls can be processed as usual even while running a
nested guest.
* Fix shadow paging use-after-free due to page tables changing outside
execution of the guest. A bug that is 16 years old and stems from an
imprecision in the very first KVM series.
* Scan IRR whenever PID.ON is true, even if PIR is empty, which avoids
a somewhat rare WARN.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini:
"Three bug fixes for x86:
- Check that nEPT/nNPT is enabled in slow flush hypercalls. If it is
not, the hypercalls can be processed as usual even while running a
nested guest
- Fix shadow paging use-after-free due to page tables changing
outside execution of the guest. A bug that is 16 years old and
stems from an imprecision in the very first KVM series
- Scan IRR whenever PID.ON is true, even if PIR is empty, which
avoids a somewhat rare WARN"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: x86: Fix shadow paging use-after-free due to unexpected GFN
KVM: x86: Fix misleading variable names and add more comments for PIR=>IRR flow
KVM: x86: Do IRR scan in __kvm_apic_update_irr even if PIR is empty
KVM: x86: check for nEPT/nNPT in slow flush hypercalls
The shadow MMU computes GFNs for direct shadow pages using sp->gfn plus
the SPTE index. This assumption breaks for shadow paging if the guest
page tables are modified between VM entries (similar to commit
aad885e774, "KVM: x86/mmu: Drop/zap existing present SPTE even
when creating an MMIO SPTE", 2026-03-27). The flow is as follows:
- a PDE is installed for a 2MB mapping, and a page in that area is
accessed. KVM creates a kvm_mmu_page consisting of 512 4KB pages;
the kvm_mmu_page is marked by FNAME(fetch) as direct-mapped because
the guest's mapping is a huge page (and thus contiguous).
- the PDE mapping is changed from outside the guest.
- the guest accesses another page in the same 2MB area. KVM installs
a new leaf SPTE and rmap entry; the SPTE uses the "correct" GFN
(i.e. based on the new mapping, as changed in the previous step) but
that GFN is outside of the [sp->gfn, sp->gfn + 511] range; therefore
the rmap entry cannot be found and removed when the kvm_mmu_page
is zapped.
- the memslot that covers the first 2MB mapping is deleted, and the
kvm_mmu_page for the now-invalid GPA is zapped. However, rmap_remove()
only looks at the [sp->gfn, sp->gfn + 511] range established in step 1,
and fails to find the rmap entry that was recorded by step 3.
- any operation that causes an rmap walk for the same page accessed
by step 3 then walks a stale rmap and dereferences a freed kvm_mmu_page.
This includes dirty logging or MMU notifier invalidations (e.g., from
MADV_DONTNEED).
The underlying issue is that KVM's walking of shadow PTEs assumes that
if a SPTE is present when KVM wants to install a non-leaf SPTE, then the
existing kvm_mmu_page must be for the correct gfn. Because the only way
for the gfn to be wrong is if KVM messed up and failed to zap a SPTE...
which shouldn't happen, but *actually* only happens in response to a
guest write.
That bug dates back literally forever, as even the first version of KVM
assumes that the GFN matches and walks into the "wrong" shadow page.
However, that was only an imprecision until 2032a93d66 ("KVM: MMU:
Don't allocate gfns page for direct mmu pages") came along.
Fix it by checking for a target gfn mismatch and zapping the existing
SPTE. That way the old SP and rmap entries are gone, KVM installs
the rmap in the right location, and everyone is happy.
Fixes: 2032a93d66 ("KVM: MMU: Don't allocate gfns page for direct mmu pages")
Fixes: 6aa8b732ca ("kvm: userspace interface")
Reported-by: Alexander Bulekov <bkov@amazon.com>
Reported-by: Fred Griffoul <fgriffo@amazon.co.uk>
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://patch.msgid.link/20260503201029.106481-1-pbonzini@redhat.com/
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Rename kvm_apic_update_irr()'s "irr_updated" and vmx_sync_pir_to_irr()'s
"got_posted_interrupt" to a more accurate "max_irr_is_from_pir", as neither
"irr_updated" nor "got_posted_interrupt" is accurate.
__kvm_apic_update_irr() and thus kvm_apic_update_irr() specifically return
true if and only if the highest priority IRQ, i.e. max_irr, is a "new"
pending IRQ from the PIR. I.e. it's possible for the IRR to be updated,
i.e. for a posted IRQ to be "got", *without* the APIs returning true.
Expand vmx_sync_pir_to_irr()'s comment to explain why it's necessary to
set KVM_REQ_EVENT only if a "new" IRQ was found, and to explain why it's
safe to do so only if a new IRQ is also the highest priority pending IRQ.
No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://patch.msgid.link/20260503201703.108231-3-pbonzini@redhat.com/
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Fall back to apic_find_highest_vector() when PID.ON is set but PIR
turns out to be empty, to correctly report the highest pending interrupt
from the existing IRR.
In a nested VM stress test, the following WARNING fires in
vmx_check_nested_events() when kvm_cpu_has_interrupt() reports a pending
interrupt but the subsequent kvm_apic_has_interrupt() (which invokes
vmx_sync_pir_to_irr() again) returns -1:
WARNING: CPU: 99 PID: 57767 at arch/x86/kvm/vmx/nested.c:4449 vmx_check_nested_events+0x6bf/0x6e0 [kvm_intel]
Call Trace:
kvm_check_and_inject_events
vcpu_enter_guest.constprop.0
vcpu_run
kvm_arch_vcpu_ioctl_run
kvm_vcpu_ioctl
__x64_sys_ioctl
do_syscall_64
entry_SYSCALL_64_after_hwframe
The root cause is a race between vmx_sync_pir_to_irr() on the target vCPU
and __vmx_deliver_posted_interrupt() on a sender vCPU. The sender
performs two individually-atomic operations that are not a single
transaction:
1. pi_test_and_set_pir(vector) -- sets the PIR bit
2. pi_test_and_set_on() -- sets PID.ON
The following interleaving triggers the bug:
Sender vCPU (IPI): Target vCPU (1st sync_pir_to_irr):
B1: set PIR[vector]
A1: pi_clear_on()
A2: pi_harvest_pir() -> sees B1 bit
A3: xchg() -> consumes bit, PIR=0
(1st sync returns correct max_irr)
B2: set PID.ON = 1
Target vCPU (2nd sync_pir_to_irr):
C1: pi_test_on() -> TRUE (from B2)
C2: pi_clear_on() -> ON=0
C3: pi_harvest_pir() -> PIR empty
C4: *max_irr = -1, early return
IRR NOT SCANNED
The interrupt is not lost (it resides in the IRR from the first sync and
is recovered on the next vcpu_enter_guest() iteration), but the incorrect
max_irr causes a spurious WARNING and a wasted L2 VM-Enter/VM-Exit cycle.
Fixes: b41f8638b9 ("KVM: VMX: Isolate pure loads from atomic XCHG when processing PIR")
Reported-by: Farrah Chen <farrah.chen@intel.com>
Analyzed-by: Chenyi Qiang <chenyi.qiang@intel.com>
Cc: stable@vger.kernel.org
Reviewed-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/kvm/20260428070349.1633238-1-chenyi.qiang@intel.com/T/
Link: https://patch.msgid.link/20260503201703.108231-2-pbonzini@redhat.com/
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Checking is_guest_mode(vcpu) is incorrect, because translate_nested_gpa()
is only valid if an L2 guest is running *with nested EPT/NPT enabled*.
Instead use the same condition as translate_nested_gpa() itself.
Cc: stable@vger.kernel.org
Reviewed-by: Sean Christopherson <seanjc@google.com>
Fixes: aee738236d ("KVM: x86: Prepare kvm_hv_flush_tlb() to handle L2's GPAs", 2022-11-18)
Link: https://patch.msgid.link/20260503200905.106077-1-pbonzini@redhat.com/
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
- sh: Fix fallout from ZERO_PAGE consolidation
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Merge tag 'sh-for-v7.1-tag2' of git://git.kernel.org/pub/scm/linux/kernel/git/glaubitz/sh-linux
Pull sh fix from John Paul Adrian Glaubitz:
"The ZERO_PAGE consolidation in v7.1, introduced a regression on sh
which made these systems unbootable.
The problem was that on sh, the initial boot parameters were
previously referenced as an array and after 6215d9f447 ("arch, mm:
consolidate empty_zero_page"), they were referenced as a pointer which
caused wrong code generation and boot hang.
This changes the declaration back to being an array which fixes the
boot hang"
* tag 'sh-for-v7.1-tag2' of git://git.kernel.org/pub/scm/linux/kernel/git/glaubitz/sh-linux:
sh: Fix fallout from ZERO_PAGE consolidation
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Merge tag 'slab-for-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab
Pull slab fixes from Vlastimil Babka:
- Stable fixes for CONFIG_SMP=n where _nolock() allocations in NMI both
at kmalloc and page allocator levels are not properly protected by
the spin_trylock() semantics on !SMP (Harry Yoo)
* tag 'slab-for-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab:
mm/slab: return NULL early from kmalloc_nolock() in NMI on UP
mm/page_alloc: return NULL early from alloc_frozen_pages_nolock() in NMI on UP
by Sebastian Andrzej Siewior.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'locking-urgent-2026-05-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fix from Ingo Molnar:
"Fix lockup in requeue-PI during signal/timeout wakeups, by Sebastian
Andrzej Siewior"
* tag 'locking-urgent-2026-05-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
futex: Prevent lockup in requeue-PI during signal/ timeout wakeup
- Fix the delayed dequeue negative lag increase fix in the
fair scheduler (Peter Zijlstra)
- Fix wakeup_preempt_fair() to do proper delayed dequeue
(Vincent Guittot)
- Clear sched_entity::rel_deadline when initializing
forked entities, which bug can cause all tasks to be
EEVDF-ineligible, causing a NULL pointer dereference
crash in pick_next_entity() (Zicheng Qu)
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'sched-urgent-2026-05-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
- Fix the delayed dequeue negative lag increase fix in the
fair scheduler (Peter Zijlstra)
- Fix wakeup_preempt_fair() to do proper delayed dequeue
(Vincent Guittot)
- Clear sched_entity::rel_deadline when initializing
forked entities, which bug can cause all tasks to be
EEVDF-ineligible, causing a NULL pointer dereference
crash in pick_next_entity() (Zicheng Qu)
* tag 'sched-urgent-2026-05-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Clear rel_deadline when initializing forked entities
sched/fair: Fix wakeup_preempt_fair() vs delayed dequeue
sched/fair: Fix the negative lag increase fix
Consolidation of empty_zero_page declarations broke boot on sh.
sh stores its initial boot parameters in a page reserved in
arch/sh/kernel/head_32.S. Before commit 6215d9f447 ("arch, mm:
consolidate empty_zero_page") this page was referenced in C code
as an array and after that commit it is referenced as a pointer.
This causes wrong code generation and boot hang.
Declare boot_params_page as an array to fix the issue.
Reported-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Tested-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Fixes: 6215d9f447 ("arch, mm: consolidate empty_zero_page")
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Artur Rojek <contact@artur-rojek.eu>
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
If pinned initialization of drm::Device::Data fails, it calls
drm::Device::release via drm_dev_put. This materializes a reference to
&drm::Device, but it's not fully constructed yet, because initializing
`data` failed. It should not be dropped either. Instead, if pinned
initialization fails, make sure drm::Device::release isn't called.
Fixes: 2e9fdbe5ec ("rust: drm: device: drop_in_place() the drm::Device in release()")
Signed-off-by: Eliot Courtney <ecourtney@nvidia.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260501-fix-drm-1-v2-1-5c4f681837bc@nvidia.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
tls_sw_splice_read() uses len when advancing rxm->offset / rxm->full_len
after skb_splice_bits(), rather than copied (the actual number of bytes
successfully spliced into the pipe). When the destination pipe cannot
accept all the requested bytes, splice_to_pipe() returns fewer bytes
than len, and 'len - copied' of data is effectively skipped over.
Fixes: e062fe99cc ("tls: splice_read: fix accessing pre-processed records")
Link: https://patch.msgid.link/20260429222944.2139041-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
cake_dump_class_stats() runs without qdisc spinlock being held.
In this first patch, I add READ_ONCE()/WRITE_ONCE() annotations for:
- flow->head
- flow->dropped
- b->backlogs[]
Fixes: 046f6fd5da ("sched: Add Common Applications Kept Enhanced (cake) qdisc")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260430061610.3503483-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
- Reject algorithms with authsizes that are too short in authencesn.
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Merge tag 'v7.1-p3' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto fix from Herbert Xu:
- Reject algorithms with authsizes that are too short in authencesn
* tag 'v7.1-p3' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: authencesn - reject short ahash digests during instance creation
- Fix a NULL pointer dereference in ntfs_index_walk_down() by validating
index block allocation.
- Fix a memory leak of the symlink target string in
ntfs_reparse_set_wsl_symlink() during error paths.
- Prevent VCN overflow and validate lowest_vcn in
ntfs_mapping_pairs_decompress() to avoid runlist corruption.
- Fix a page reference leak in ntfs_write_iomap_end_resident() when
attribute search context allocation fails.
- Fix an invalid PTR_ERR() usage on a valid folio pointer in
__ntfs_bitmap_set_bits_in_run().
- Correct directory link counting by dropping nlink only when the MFT
record link count reaches zero for WIN32/DOS aliases.
- Fix an uninitialized variable usage in ntfs_mapping_pairs_decompress()
by returning an error pointer directly.
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Merge tag 'ntfs-for-7.1-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/ntfs
Pull ntfs fixes from Namjae Jeon:
- Fix a NULL pointer dereference in ntfs_index_walk_down() by
validating index block allocation
- Fix a memory leak of the symlink target string in
ntfs_reparse_set_wsl_symlink() during error paths
- Prevent VCN overflow and validate lowest_vcn in
ntfs_mapping_pairs_decompress() to avoid runlist corruption
- Fix a page reference leak in ntfs_write_iomap_end_resident()
when attribute search context allocation fails
- Fix an invalid PTR_ERR() usage on a valid folio pointer in
__ntfs_bitmap_set_bits_in_run()
- Correct directory link counting by dropping nlink only when
the MFT record link count reaches zero for WIN32/DOS aliases
- Fix an uninitialized variable in ntfs_mapping_pairs_decompress()
by returning an error pointer directly
* tag 'ntfs-for-7.1-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/ntfs:
ntfs: Use return instead of goto in ntfs_mapping_pairs_decompress()
ntfs: drop nlink once for WIN32/DOS aliases
ntfs: fix invalid PTR_ERR() usage in __ntfs_bitmap_set_bits_in_run()
ntfs: fix error handling in ntfs_write_iomap_end_resident()
ntfs: fix VCN overflow in ntfs_mapping_pairs_decompress()
ntfs: fix WSL symlink target leak on reparse failure
ntfs: fix NULL dereference in ntfs_index_walk_down()
