tjh.dev
Linux kernel
============
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In order to build the documentation, use ``make htmldocs`` or
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There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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Add some more Zen6 models.
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://patch.msgid.link/20251029123056.19987-1-bp@kernel.org
Leyvi Rose reported that his X86_NATIVE_CPU=y build is failing because our
instruction decoder doesn't support SSE4a and the AMDGPU code seems to be
generating those with his compiler of choice (CLANG+LTO).
Now, our normal build flags disable SSE MMX SSE2 3DNOW AVX, but then
CC_FLAGS_FPU re-enable SSE SSE2.
Since nothing mentions SSE3 or SSE4, I'm assuming that -msse (or its negative)
control all SSE variants -- but why then explicitly enumerate SSE2 ?
Anyway, until the instruction decoder gets fixed, explicitly disallow SSE4a
(an AMD specific SSE4 extension).
Fixes: ea1dcca1de12 ("x86/kbuild/64: Add the CONFIG_X86_NATIVE_CPU option to locally optimize the kernel with '-march=native'")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Arisu Tachibana <arisu.tachibana@miraclelinux.com>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Cc: <stable@kernel.org>
Sean reported [1] the following splat when running KVM tests:
WARNING: CPU: 232 PID: 15391 at xfd_validate_state+0x65/0x70
Call Trace:
<TASK>
fpu__clear_user_states+0x9c/0x100
arch_do_signal_or_restart+0x142/0x210
exit_to_user_mode_loop+0x55/0x100
do_syscall_64+0x205/0x2c0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
Chao further identified [2] a reproducible scenario involving signal
delivery: a non-AMX task is preempted by an AMX-enabled task which
modifies the XFD MSR.
When the non-AMX task resumes and reloads XSTATE with init values,
a warning is triggered due to a mismatch between fpstate::xfd and the
CPU's current XFD state. fpu__clear_user_states() does not currently
re-synchronize the XFD state after such preemption.
Invoke xfd_update_state() which detects and corrects the mismatch if
there is a dynamic feature.
This also benefits the sigreturn path, as fpu__restore_sig() may call
fpu__clear_user_states() when the sigframe is inaccessible.
[ dhansen: minor changelog munging ]
Closes: https://lore.kernel.org/lkml/aDCo_SczQOUaB2rS@google.com [1]
Fixes: 672365477ae8a ("x86/fpu: Update XFD state where required")
Reported-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Chao Gao <chao.gao@intel.com>
Tested-by: Chao Gao <chao.gao@intel.com>
Link: https://lore.kernel.org/all/aDWbctO%2FRfTGiCg3@intel.com [2]
Cc:stable@vger.kernel.org
Link: https://patch.msgid.link/20250610001700.4097-1-chang.seok.bae%40intel.com
There's an issue with RDSEED's 16-bit and 32-bit register output
variants on Zen5 which return a random value of 0 "at a rate inconsistent
with randomness while incorrectly signaling success (CF=1)". Search the
web for AMD-SB-7055 for more detail.
Add a fix glue which checks microcode revisions.
[ bp: Add microcode revisions checking, rewrite. ]
Cc: stable@vger.kernel.org
Signed-off-by: Gregory Price <gourry@gourry.net>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20251018024010.4112396-1-gourry@gourry.net
Limit Entrysign sha256 signature checking to CPUs in the range Zen1-Zen5.
X86_BUG cannot be used here because the loading on the BSP happens way
too early, before the cpufeatures machinery has been set up.
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://patch.msgid.link/all/20251023124629.5385-1-bp@kernel.org
Pull char/misc driver fixes from Greg KH:
"Here are some small char/misc/android driver fixes for 6.18-rc3 for
reported issues. Included in here are:
- rust binder fixes for reported issues
- mei device id addition
- mei driver fixes
- comedi bugfix
- most usb driver bugfixes
- fastrpc memory leak fix
All of these have been in linux-next for a while with no reported
issues"
* tag 'char-misc-6.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
most: usb: hdm_probe: Fix calling put_device() before device initialization
most: usb: Fix use-after-free in hdm_disconnect
binder: remove "invalid inc weak" check
mei: txe: fix initialization order
comedi: fix divide-by-zero in comedi_buf_munge()
mei: late_bind: Fix -Wincompatible-function-pointer-types-strict
misc: fastrpc: Fix dma_buf object leak in fastrpc_map_lookup
mei: me: add wildcat lake P DID
misc: amd-sbi: Clarify that this is a BMC driver
nvmem: rcar-efuse: add missing MODULE_DEVICE_TABLE
binder: Fix missing kernel-doc entries in binder.c
rust_binder: report freeze notification only when fully frozen
rust_binder: don't delete FreezeListener if there are pending duplicates
rust_binder: freeze_notif_done should resend if wrong state
rust_binder: remove warning about orphan mappings
rust_binder: clean `clippy::mem_replace_with_default` warning
Pull staging driver fixes from Greg KH:
"Here are some small staging driver fixes for the gpib subsystem to
resolve some reported issues. Included in here are:
- memory leak fixes
- error code fixes
- proper protocol fixes
All of these have been in linux-next for almost 2 weeks now with no
reported issues"
* tag 'staging-6.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
staging: gpib: Fix device reference leak in fmh_gpib driver
staging: gpib: Return -EINTR on device clear
staging: gpib: Fix sending clear and trigger events
staging: gpib: Fix no EOI on 1 and 2 byte writes
The early error path in hdm_probe() can jump to err_free_mdev before
&mdev->dev has been initialized with device_initialize(). Calling
put_device(&mdev->dev) there triggers a device core WARN and ends up
invoking kref_put(&kobj->kref, kobject_release) on an uninitialized
kobject.
In this path the private struct was only kmalloc'ed and the intended
release is effectively kfree(mdev) anyway, so free it directly instead
of calling put_device() on an uninitialized device.
This removes the WARNING and fixes the pre-initialization error path.
Fixes: 97a6f772f36b ("drivers: most: add USB adapter driver")
Cc: stable <stable@kernel.org>
Signed-off-by: Victoria Votokina <Victoria.Votokina@kaspersky.com>
Link: https://patch.msgid.link/20251010105241.4087114-3-Victoria.Votokina@kaspersky.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull tty/serial driver fixes from Greg KH:
"Here are some small tty and serial driver fixes for reported issues.
Included in here are:
- sh-sci serial driver fixes
- 8250_dw and _mtk driver fixes
- sc16is7xx driver bugfix
- new 8250_exar device ids added
All of these have been in linux-next this past week with no reported
issues"
* tag 'tty-6.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
serial: 8250_mtk: Enable baud clock and manage in runtime PM
serial: 8250_dw: handle reset control deassert error
dt-bindings: serial: sh-sci: Fix r8a78000 interrupts
serial: sc16is7xx: remove useless enable of enhanced features
serial: 8250_exar: add support for Advantech 2 port card with Device ID 0x0018
tty: serial: sh-sci: fix RSCI FIFO overrun handling
The fmh_gpib driver contains a device reference count leak in
fmh_gpib_attach_impl() where driver_find_device() increases the
reference count of the device by get_device() when matching but this
reference is not properly decreased. Add put_device() in
fmh_gpib_detach(), which ensures that the reference count of the
device is correctly managed.
Found by code review.
Cc: stable <stable@kernel.org>
Fixes: 8e4841a0888c ("staging: gpib: Add Frank Mori Hess FPGA PCI GPIB driver")
Signed-off-by: Ma Ke <make24@iscas.ac.cn>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
hdm_disconnect() calls most_deregister_interface(), which eventually
unregisters the MOST interface device with device_unregister(iface->dev).
If that drops the last reference, the device core may call release_mdev()
immediately while hdm_disconnect() is still executing.
The old code also freed several mdev-owned allocations in
hdm_disconnect() and then performed additional put_device() calls.
Depending on refcount order, this could lead to use-after-free or
double-free when release_mdev() ran (or when unregister paths also
performed puts).
Fix by moving the frees of mdev-owned allocations into release_mdev(),
so they happen exactly once when the device is truly released, and by
dropping the extra put_device() calls in hdm_disconnect() that are
redundant after device_unregister() and most_deregister_interface().
This addresses the KASAN slab-use-after-free reported by syzbot in
hdm_disconnect(). See report and stack traces in the bug link below.
Reported-by: syzbot+916742d5d24f6c254761@syzkaller.appspotmail.com
Cc: stable <stable@kernel.org>
Closes: https://syzkaller.appspot.com/bug?extid=916742d5d24f6c254761
Fixes: 97a6f772f36b ("drivers: most: add USB adapter driver")
Signed-off-by: Victoria Votokina <Victoria.Votokina@kaspersky.com>
Link: https://patch.msgid.link/20251010105241.4087114-2-Victoria.Votokina@kaspersky.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull USB driver fixes from Greg KH:
"Here are some small USB driver fixes and new device ids for 6.18-rc3.
Included in here are:
- new option serial driver device ids added
- dt bindings fixes for numerous platforms
- xhci bugfixes for many reported regressions
- usbio dependency bugfix
- dwc3 driver fix
- raw-gadget bugfix
All of these have been in linux-next this week with no reported issues"
* tag 'usb-6.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
USB: serial: option: add Telit FN920C04 ECM compositions
USB: serial: option: add Quectel RG255C
tcpm: switch check for role_sw device with fw_node
usb/core/quirks: Add Huawei ME906S to wakeup quirk
usb: raw-gadget: do not limit transfer length
USB: serial: option: add UNISOC UIS7720
xhci: dbc: enable back DbC in resume if it was enabled before suspend
xhci: dbc: fix bogus 1024 byte prefix if ttyDBC read races with stall event
usb: xhci-pci: Fix USB2-only root hub registration
dt-bindings: usb: qcom,snps-dwc3: Fix bindings for X1E80100
usb: misc: Add x86 dependency for Intel USBIO driver
dt-bindings: usb: switch: split out ports definition
usb: dwc3: Don't call clk_bulk_disable_unprepare() twice
dt-bindings: usb: dwc3-imx8mp: dma-range is required only for imx8mp
Some MediaTek SoCs got a gated UART baud clock, which currently gets
disabled as the clk subsystem believes it would be unused. This results in
the uart freezing right after "clk: Disabling unused clocks" on those
platforms.
Request the baud clock to be prepared and enabled during probe, and to
restore run-time power management capabilities to what it was before commit
e32a83c70cf9 ("serial: 8250-mtk: modify mtk uart power and clock
management") disable and unprepare the baud clock when suspending the UART,
prepare and enable it again when resuming it.
Fixes: e32a83c70cf9 ("serial: 8250-mtk: modify mtk uart power and clock management")
Fixes: b6c7ff2693ddc ("serial: 8250_mtk: Simplify clock sequencing and runtime PM")
Cc: stable <stable@kernel.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Link: https://patch.msgid.link/de5197ccc31e1dab0965cabcc11ca92e67246cf6.1758058441.git.daniel@makrotopia.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When the ATN (Attention) line is asserted during a read we get a
NIUSB_ATN_STATE_ERROR during a read. For the controller to send a
device clear it asserts ATN. Normally this is an error but in the case
of a device clear it should be regarded as an interrupt.
Return -EINTR when the Device Clear Active State (DCAS) is entered
else signal an error with dev_dbg with status instead of just dev_err.
Signed-off-by: Dave Penkler <dpenkler@gmail.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are no scenarios where a weak increment is invalid on binder_node.
The only possible case where it could be invalid is if the kernel
delivers BR_DECREFS to the process that owns the node, and then
increments the weak refcount again, effectively "reviving" a dead node.
However, that is not possible: when the BR_DECREFS command is delivered,
the kernel removes and frees the binder_node. The fact that you were
able to call binder_inc_node_nilocked() implies that the node is not yet
destroyed, which implies that BR_DECREFS has not been delivered to
userspace, so incrementing the weak refcount is valid.
Note that it's currently possible to trigger this condition if the owner
calls BINDER_THREAD_EXIT while node->has_weak_ref is true. This causes
BC_INCREFS on binder_ref instances to fail when they should not.
Cc: stable@vger.kernel.org
Fixes: 457b9a6f09f0 ("Staging: android: add binder driver")
Reported-by: Yu-Ting Tseng <yutingtseng@google.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patch.msgid.link/20251015-binder-weak-inc-v1-1-7914b092c371@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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