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Linux kernel
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several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
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the problems which may result by upgrading your kernel.
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Pull xen fixlet from Juergen Gross:
"A single cleanup patch for the Xen balloon driver"
* tag 'for-linus-5.18-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen/balloon: don't use PV mode extra memory for zone device allocations
Pull x86 fixes from Thomas Gleixner:
"Two x86 fixes related to TSX:
- Use either MSR_TSX_FORCE_ABORT or MSR_IA32_TSX_CTRL to disable TSX
to cover all CPUs which allow to disable it.
- Disable TSX development mode at boot so that a microcode update
which provides TSX development mode does not suddenly make the
system vulnerable to TSX Asynchronous Abort"
* tag 'x86-urgent-2022-04-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/tsx: Disable TSX development mode at boot
x86/tsx: Use MSR_TSX_CTRL to clear CPUID bits
When running as a Xen PV guest use the extra memory (memory which isn't
allocated for the guest at boot time) only for ballooning purposes and
not for zone device allocations. This will remove some code without any
lack of functionality.
While at it move some code to get rid of another #ifdef.
Remove a comment which is stale since some time now.
Signed-off-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20220407093857.1485-1-jgross@suse.com
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Pull timer fixes from Thomas Gleixner:
"A small set of fixes for the timers core:
- Fix the warning condition in __run_timers() which does not take
into account that a CPU base (especially the deferrable base) never
has a timer armed on it and therefore the next_expiry value can
become stale.
- Replace a WARN_ON() in the NOHZ code with a WARN_ON_ONCE() to
prevent endless spam in dmesg.
- Remove the double star from a comment which is not meant to be in
kernel-doc format"
* tag 'timers-urgent-2022-04-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tick/sched: Fix non-kernel-doc comment
tick/nohz: Use WARN_ON_ONCE() to prevent console saturation
timers: Fix warning condition in __run_timers()
A microcode update on some Intel processors causes all TSX transactions
to always abort by default[*]. Microcode also added functionality to
re-enable TSX for development purposes. With this microcode loaded, if
tsx=on was passed on the cmdline, and TSX development mode was already
enabled before the kernel boot, it may make the system vulnerable to TSX
Asynchronous Abort (TAA).
To be on safer side, unconditionally disable TSX development mode during
boot. If a viable use case appears, this can be revisited later.
[*]: Intel TSX Disable Update for Selected Processors, doc ID: 643557
[ bp: Drop unstable web link, massage heavily. ]
Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Neelima Krishnan <neelima.krishnan@intel.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/347bd844da3a333a9793c6687d4e4eb3b2419a3e.1646943780.git.pawan.kumar.gupta@linux.intel.com
is_xen_pmu() is taking the cpu number as parameter, but it is not using
it. Instead it just tests whether the Xen PMU initialization on the
current cpu did succeed. As this test is done by checking a percpu
pointer, preemption needs to be disabled in order to avoid switching
the cpu while doing the test. While resuming from suspend() this seems
not to be the case:
[ 88.082751] ACPI: PM: Low-level resume complete
[ 88.087933] ACPI: EC: EC started
[ 88.091464] ACPI: PM: Restoring platform NVS memory
[ 88.097166] xen_acpi_processor: Uploading Xen processor PM info
[ 88.103850] Enabling non-boot CPUs ...
[ 88.108128] installing Xen timer for CPU 1
[ 88.112763] BUG: using smp_processor_id() in preemptible [00000000] code: systemd-sleep/7138
[ 88.122256] caller is is_xen_pmu+0x12/0x30
[ 88.126937] CPU: 0 PID: 7138 Comm: systemd-sleep Tainted: G W 5.16.13-2.fc32.qubes.x86_64 #1
[ 88.137939] Hardware name: Star Labs StarBook/StarBook, BIOS 7.97 03/21/2022
[ 88.145930] Call Trace:
[ 88.148757] <TASK>
[ 88.151193] dump_stack_lvl+0x48/0x5e
[ 88.155381] check_preemption_disabled+0xde/0xe0
[ 88.160641] is_xen_pmu+0x12/0x30
[ 88.164441] xen_smp_intr_init_pv+0x75/0x100
Fix that by replacing is_xen_pmu() by a simple boolean variable which
reflects the Xen PMU initialization state on cpu 0.
Modify xen_pmu_init() to return early in case it is being called for a
cpu other than cpu 0 and the boolean variable not being set.
Fixes: bf6dfb154d93 ("xen/PMU: PMU emulation code")
Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20220325142002.31789-1-jgross@suse.com
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Pull SMP fixes from Thomas Gleixner:
"Two fixes for the SMP core:
- Make the warning condition in flush_smp_call_function_queue()
correct, which checked a just emptied list head for being empty
instead of validating that there was no pending entry on the
offlined CPU at all.
- The @cpu member of struct cpuhp_cpu_state is initialized when the
CPU hotplug thread for the upcoming CPU is created. That's too late
because the creation of the thread can fail and then the following
rollback operates on CPU0. Get rid of the CPU member and hand the
CPU number to the involved functions directly"
* tag 'smp-urgent-2022-04-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
cpu/hotplug: Remove the 'cpu' member of cpuhp_cpu_state
smp: Fix offline cpu check in flush_smp_call_function_queue()
Fixes the following W=1 kernel build warning:
kernel/time/tick-sched.c:1563: warning: This comment starts with '/**',
but isn't a kernel-doc comment.
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20220214084739.63228-1-jiapeng.chong@linux.alibaba.com
tsx_clear_cpuid() uses MSR_TSX_FORCE_ABORT to clear CPUID.RTM and
CPUID.HLE. Not all CPUs support MSR_TSX_FORCE_ABORT, alternatively use
MSR_IA32_TSX_CTRL when supported.
[ bp: Document how and why TSX gets disabled. ]
Fixes: 293649307ef9 ("x86/tsx: Clear CPUID bits when TSX always force aborts")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Neelima Krishnan <neelima.krishnan@intel.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/5b323e77e251a9c8bcdda498c5cc0095be1e1d3c.1646943780.git.pawan.kumar.gupta@linux.intel.com
If a xen domain with at least two VCPUs has a PCI device attached which
enters the D3hot state during suspend, the kernel may hang while
resuming, depending on the core on which an async resume task gets
scheduled.
The bug occurs because xen's do_suspend calls dpm_resume_start while
only the timer of the boot CPU has been resumed (when xen_suspend called
syscore_resume), before calling xen_arch_suspend to resume the timers of
the other CPUs. This breaks pci_dev_d3_sleep.
Thus this patch moves the call to xen_arch_resume before the call to
dpm_resume_start, eliminating the hangs and restoring the stack-like
structure of the suspend/restore procedure.
Signed-off-by: Jakub Kądziołka <niedzejkob@invisiblethingslab.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20220323012103.2537-1-niedzejkob@invisiblethingslab.com
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Pull irq fix from Thomas Gleixner:
"A single fix for the interrupt affinity spreading logic to take into
account that there can be an imbalance between present and possible
CPUs, which causes already assigned bits to be overwritten"
* tag 'irq-urgent-2022-04-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq/affinity: Consider that CPUs on nodes can be unbalanced
Currently the setting of the 'cpu' member of struct cpuhp_cpu_state in
cpuhp_create() is too late as it is used earlier in _cpu_up().
If kzalloc_node() in __smpboot_create_thread() fails then the rollback will
be done with st->cpu==0 causing CPU0 to be erroneously set to be dying,
causing the scheduler to get mightily confused and throw its toys out of
the pram.
However the cpu number is actually available directly, so simply remove
the 'cpu' member and avoid the problem in the first place.
Fixes: 2ea46c6fc945 ("cpumask/hotplug: Fix cpu_dying() state tracking")
Signed-off-by: Steven Price <steven.price@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20220411152233.474129-2-steven.price@arm.com
While running some testing on code that happened to allow the variable
tick_nohz_full_running to get set but with no "possible" NOHZ cores to
back up that setting, this warning triggered:
if (unlikely(tick_do_timer_cpu == TICK_DO_TIMER_NONE))
WARN_ON(tick_nohz_full_running);
The console was overwhemled with an endless stream of one WARN per tick
per core and there was no way to even see what was going on w/o using a
serial console to capture it and then trace it back to this.
Change it to WARN_ON_ONCE().
Fixes: 08ae95f4fd3b ("nohz_full: Allow the boot CPU to be nohz_full")
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20211206145950.10927-3-paul.gortmaker@windriver.com
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