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Linux kernel
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Pull x86 fixes from Thomas Gleixner:
- Fix 32-bit PTI for real.
pti_clone_entry_text() is called twice, once before initcalls so that
initcalls can use the user-mode helper and then again after text is
set read only. Setting read only on 32-bit might break up the PMD
mapping, which makes the second invocation of pti_clone_entry_text()
find the mappings out of sync and failing.
Allow the second call to split the existing PMDs in the user mapping
and synchronize with the kernel mapping.
- Don't make acpi_mp_wake_mailbox read-only after init as the mail box
must be writable in the case that CPU hotplug operations happen after
boot. Otherwise the attempt to start a CPU crashes with a write to
read only memory.
- Add a missing sanity check in mtrr_save_state() to ensure that the
fixed MTRR MSRs are supported.
Otherwise mtrr_save_state() ends up in a #GP, which is fixed up, but
the WARN_ON() can bring systems down when panic on warn is set.
* tag 'x86-urgent-2024-08-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mtrr: Check if fixed MTRRs exist before saving them
x86/paravirt: Fix incorrect virt spinlock setting on bare metal
x86/acpi: Remove __ro_after_init from acpi_mp_wake_mailbox
x86/mm: Fix PTI for i386 some more
Pull time keeping fixes from Thomas Gleixner:
- Fix a couple of issues in the NTP code where user supplied values are
neither sanity checked nor clamped to the operating range. This
results in integer overflows and eventualy NTP getting out of sync.
According to the history the sanity checks had been removed in favor
of clamping the values, but the clamping never worked correctly under
all circumstances. The NTP people asked to not bring the sanity
checks back as it might break existing applications.
Make the clamping work correctly and add it where it's missing
- If adjtimex() sets the clock it has to trigger the hrtimer subsystem
so it can adjust and if the clock was set into the future expire
timers if needed. The caller should provide a bitmask to tell
hrtimers which clocks have been adjusted.
adjtimex() uses not the proper constant and uses CLOCK_REALTIME
instead, which is 0. So hrtimers adjusts only the clocks, but does
not check for expired timers, which might make them expire really
late. Use the proper bitmask constant instead.
* tag 'timers-urgent-2024-08-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timekeeping: Fix bogus clock_was_set() invocation in do_adjtimex()
ntp: Safeguard against time_constant overflow
ntp: Clamp maxerror and esterror to operating range
MTRRs have an obsolete fixed variant for fine grained caching control
of the 640K-1MB region that uses separate MSRs. This fixed variant has
a separate capability bit in the MTRR capability MSR.
So far all x86 CPUs which support MTRR have this separate bit set, so it
went unnoticed that mtrr_save_state() does not check the capability bit
before accessing the fixed MTRR MSRs.
Though on a CPU that does not support the fixed MTRR capability this
results in a #GP. The #GP itself is harmless because the RDMSR fault is
handled gracefully, but results in a WARN_ON().
Add the missing capability check to prevent this.
Fixes: 2b1f6278d77c ("[PATCH] x86: Save the MTRRs of the BSP before booting an AP")
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20240808000244.946864-1-ak@linux.intel.com
Pull irq fixes from Thomas Gleixner:
"Three small fixes for interrupt core and drivers:
- The interrupt core fails to honor caller supplied affinity hints
for non-managed interrupts and uses the system default affinity on
startup instead. Set the missing flag in the descriptor to tell the
core to use the provided affinity.
- Fix a shift out of bounds error in the Xilinx driver
- Handle switching to level trigger correctly in the RISCV APLIC
driver. It failed to retrigger the interrupt which causes it to
become stale"
* tag 'irq-urgent-2024-08-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/riscv-aplic: Retrigger MSI interrupt on source configuration
irqchip/xilinx: Fix shift out of bounds
genirq/irqdesc: Honor caller provided affinity in alloc_desc()
The addition of the bases argument to clock_was_set() fixed up all call
sites correctly except for do_adjtimex(). This uses CLOCK_REALTIME
instead of CLOCK_SET_WALL as argument. CLOCK_REALTIME is 0.
As a result the effect of that clock_was_set() notification is incomplete
and might result in timers expiring late because the hrtimer code does
not re-evaluate the affected clock bases.
Use CLOCK_SET_WALL instead of CLOCK_REALTIME to tell the hrtimers code
which clock bases need to be re-evaluated.
Fixes: 17a1b8826b45 ("hrtimer: Add bases argument to clock_was_set()")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/877ccx7igo.ffs@tglx
The kernel can change spinlock behavior when running as a guest. But this
guest-friendly behavior causes performance problems on bare metal.
The kernel uses a static key to switch between the two modes.
In theory, the static key is enabled by default (run in guest mode) and
should be disabled for bare metal (and in some guests that want native
behavior or paravirt spinlock).
A performance drop is reported when running encode/decode workload and
BenchSEE cache sub-workload.
Bisect points to commit ce0a1b608bfc ("x86/paravirt: Silence unused
native_pv_lock_init() function warning"). When CONFIG_PARAVIRT_SPINLOCKS is
disabled the virt_spin_lock_key is incorrectly set to true on bare
metal. The qspinlock degenerates to test-and-set spinlock, which decreases
the performance on bare metal.
Set the default value of virt_spin_lock_key to false. If booting in a VM,
enable this key. Later during the VM initialization, if other
high-efficient spinlock is preferred (e.g. paravirt-spinlock), or the user
wants the native qspinlock (via nopvspin boot commandline), the
virt_spin_lock_key is disabled accordingly.
This results in the following decision matrix:
X86_FEATURE_HYPERVISOR Y Y Y N
CONFIG_PARAVIRT_SPINLOCKS Y Y N Y/N
PV spinlock Y N N Y/N
virt_spin_lock_key N Y/N Y N
Fixes: ce0a1b608bfc ("x86/paravirt: Silence unused native_pv_lock_init() function warning")
Reported-by: Prem Nath Dey <prem.nath.dey@intel.com>
Reported-by: Xiaoping Zhou <xiaoping.zhou@intel.com>
Suggested-by: Dave Hansen <dave.hansen@linux.intel.com>
Suggested-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Suggested-by: Nikolay Borisov <nik.borisov@suse.com>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Nikolay Borisov <nik.borisov@suse.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20240806112207.29792-1-yu.c.chen@intel.com
Pull USB fixes from Greg KH:
"Here are a number of small USB driver fixes for reported issues for
6.11-rc3. Included in here are:
- usb serial driver MODULE_DESCRIPTION() updates
- usb serial driver fixes
- typec driver fixes
- usb-ip driver fix
- gadget driver fixes
- dt binding update
All of these have been in linux-next with no reported issues"
* tag 'usb-6.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
usb: typec: ucsi: Fix a deadlock in ucsi_send_command_common()
usb: typec: tcpm: avoid sink goto SNK_UNATTACHED state if not received source capability message
usb: gadget: f_fs: pull out f->disable() from ffs_func_set_alt()
usb: gadget: f_fs: restore ffs_func_disable() functionality
USB: serial: debug: do not echo input by default
usb: typec: tipd: Delete extra semi-colon
usb: typec: tipd: Fix dereferencing freeing memory in tps6598x_apply_patch()
usb: gadget: u_serial: Set start_delayed during suspend
usb: typec: tcpci: Fix error code in tcpci_check_std_output_cap()
usb: typec: fsa4480: Check if the chip is really there
usb: gadget: core: Check for unset descriptor
usb: vhci-hcd: Do not drop references before new references are gained
usb: gadget: u_audio: Check return codes from usb_ep_enable and config_ep_by_speed.
usb: gadget: midi2: Fix the response for FB info with block 0xff
dt-bindings: usb: microchip,usb2514: Add USB2517 compatible
USB: serial: garmin_gps: use struct_size() to allocate pkt
USB: serial: garmin_gps: annotate struct garmin_packet with __counted_by
USB: serial: add missing MODULE_DESCRIPTION() macros
USB: serial: spcp8x5: remove unused struct 'spcp8x5_usb_ctrl_arg'
The section 4.5.2 of the RISC-V AIA specification says that "any write
to a sourcecfg register of an APLIC might (or might not) cause the
corresponding interrupt-pending bit to be set to one if the rectified
input value is high (= 1) under the new source mode."
When the interrupt type is changed in the sourcecfg register, the APLIC
device might not set the corresponding pending bit, so the interrupt might
never become pending.
To handle sourcecfg register changes for level-triggered interrupts in MSI
mode, manually set the pending bit for retriggering interrupt so it gets
retriggered if it was already asserted.
Fixes: ca8df97fe679 ("irqchip/riscv-aplic: Add support for MSI-mode")
Signed-off-by: Yong-Xuan Wang <yongxuan.wang@sifive.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Vincent Chen <vincent.chen@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20240809071049.2454-1-yongxuan.wang@sifive.com
Using syzkaller with the recently reintroduced signed integer overflow
sanitizer produces this UBSAN report:
UBSAN: signed-integer-overflow in ../kernel/time/ntp.c:738:18
9223372036854775806 + 4 cannot be represented in type 'long'
Call Trace:
handle_overflow+0x171/0x1b0
__do_adjtimex+0x1236/0x1440
do_adjtimex+0x2be/0x740
The user supplied time_constant value is incremented by four and then
clamped to the operating range.
Before commit eea83d896e31 ("ntp: NTP4 user space bits update") the user
supplied value was sanity checked to be in the operating range. That change
removed the sanity check and relied on clamping after incrementing which
does not work correctly when the user supplied value is in the overflow
zone of the '+ 4' operation.
The operation requires CAP_SYS_TIME and the side effect of the overflow is
NTP getting out of sync.
Similar to the fixups for time_maxerror and time_esterror, clamp the user
space supplied value to the operating range.
[ tglx: Switch to clamping ]
Fixes: eea83d896e31 ("ntp: NTP4 user space bits update")
Signed-off-by: Justin Stitt <justinstitt@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20240517-b4-sio-ntp-c-v2-1-f3a80096f36f@google.com
Closes: https://github.com/KSPP/linux/issues/352
On a platform using the "Multiprocessor Wakeup Structure"[1] to startup
secondary CPUs the control processor needs to memremap() the physical
address of the MP Wakeup Structure mailbox to the variable
acpi_mp_wake_mailbox, which holds the virtual address of mailbox.
To wake up the AP the control processor writes the APIC ID of AP, the
wakeup vector and the ACPI_MP_WAKE_COMMAND_WAKEUP command into the mailbox.
Current implementation doesn't consider the case which restricts boot time
CPU bringup to 1 with the kernel parameter "maxcpus=1" and brings other
CPUs online later from user space as it sets acpi_mp_wake_mailbox to
read-only after init. So when the first AP is tried to brought online
after init, the attempt to update the variable results in a kernel panic.
The memremap() call that initializes the variable cannot be moved into
acpi_parse_mp_wake() because memremap() is not functional at that point in
the boot process. Also as the APs might never be brought up, keep the
memremap() call in acpi_wakeup_cpu() so that the operation only takes place
when needed.
Fixes: 24dd05da8c79 ("x86/apic: Mark acpi_mp_wake_* variables as __ro_after_init")
Signed-off-by: Zhiquan Li <zhiquan1.li@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Link: https://lore.kernel.org/all/20240805103531.1230635-1-zhiquan1.li@intel.com
Pull tty / serial driver fixes from Greg KH:
"Here are some small tty and serial driver fixes for reported problems
for 6.11-rc3. Included in here are:
- sc16is7xx serial driver fixes
- uartclk bugfix for a divide by zero issue
- conmakehash userspace build issue fix
All of these have been in linux-next for a while with no reported
issues"
* tag 'tty-6.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
tty: vt: conmakehash: cope with abs_srctree no longer in env
serial: sc16is7xx: fix invalid FIFO access with special register set
serial: sc16is7xx: fix TX fifo corruption
serial: core: check uartclk for zero to avoid divide by zero
The function returns with the ppm_lock held if the PPM is
busy or there's an error.
Reported-and-tested-by: Luciano Coelho <luciano.coelho@intel.com>
Fixes: 5e9c1662a89b ("usb: typec: ucsi: rework command execution functions")
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reported-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/20240806112029.2984319-1-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The device tree property 'xlnx,kind-of-intr' is sanity checked that the
bitmask contains only set bits which are in the range of the number of
interrupts supported by the controller.
The check is done by shifting the mask right by the number of supported
interrupts and checking the result for zero.
The data type of the mask is u32 and the number of supported interrupts is
up to 32. In case of 32 interrupts the shift is out of bounds, resulting in
a mismatch warning. The out of bounds condition is also reported by UBSAN:
UBSAN: shift-out-of-bounds in irq-xilinx-intc.c:332:22
shift exponent 32 is too large for 32-bit type 'unsigned int'
Fix it by promoting the mask to u64 for the test.
Fixes: d50466c90724 ("microblaze: intc: Refactor DT sanity check")
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/1723186944-3571957-1-git-send-email-radhey.shyam.pandey@amd.com
Using syzkaller alongside the newly reintroduced signed integer overflow
sanitizer spits out this report:
UBSAN: signed-integer-overflow in ../kernel/time/ntp.c:461:16
9223372036854775807 + 500 cannot be represented in type 'long'
Call Trace:
handle_overflow+0x171/0x1b0
second_overflow+0x2d6/0x500
accumulate_nsecs_to_secs+0x60/0x160
timekeeping_advance+0x1fe/0x890
update_wall_time+0x10/0x30
time_maxerror is unconditionally incremented and the result is checked
against NTP_PHASE_LIMIT, but the increment itself can overflow, resulting
in wrap-around to negative space.
Before commit eea83d896e31 ("ntp: NTP4 user space bits update") the user
supplied value was sanity checked to be in the operating range. That change
removed the sanity check and relied on clamping in handle_overflow() which
does not work correctly when the user supplied value is in the overflow
zone of the '+ 500' operation.
The operation requires CAP_SYS_TIME and the side effect of the overflow is
NTP getting out of sync.
Miroslav confirmed that the input value should be clamped to the operating
range and the same applies to time_esterror. The latter is not used by the
kernel, but the value still should be in the operating range as it was
before the sanity check got removed.
Clamp them to the operating range.
[ tglx: Changed it to clamping and included time_esterror ]
Fixes: eea83d896e31 ("ntp: NTP4 user space bits update")
Signed-off-by: Justin Stitt <justinstitt@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Link: https://lore.kernel.org/all/20240517-b4-sio-ntp-usec-v2-1-d539180f2b79@google.com
Closes: https://github.com/KSPP/linux/issues/354
So it turns out that we have to do two passes of
pti_clone_entry_text(), once before initcalls, such that device and
late initcalls can use user-mode-helper / modprobe and once after
free_initmem() / mark_readonly().
Now obviously mark_readonly() can cause PMD splits, and
pti_clone_pgtable() doesn't like that much.
Allow the late clone to split PMDs so that pagetables stay in sync.
[peterz: Changelog and comments]
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lkml.kernel.org/r/20240806184843.GX37996@noisy.programming.kicks-ass.net
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