The commit 2d7f00b2f0 ("rcu: Suppress smp_processor_id() complaint
in synchronize_rcu_expedited_wait()") disabled preemption around
dump_cpu_task() to suppress warning on its usage within preemtible context.
Calling dump_cpu_task() doesn't required to be in non-preemptible context
except for suppressing the smp_processor_id() warning.
As the smp_processor_id() is evaluated along with in_hardirq()
to check if it's in interrupt context, this patch removes the need
for its preemtion disablement by reordering the condition so that
smp_processor_id() only gets evaluated when it's in interrupt context.
Signed-off-by: Ryo Takakura <takakura@valinux.co.jp>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
During CSD-lock stalls, the additional information output by expedited
RCU CPU stall warnings is usually redundant, flooding the console for
not good reason. However, this has been the way things work for a few
years. This commit therefore uses rcutree.csd_lock_suppress_rcu_stall
kernel boot parameter that causes expedited RCU CPU stall warnings to
be abbreviated to a single line when there is at least one CPU that has
been stuck waiting for CSD lock for more than five seconds.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
This commit extracts the RCU CPU stall-warning report code from
synchronize_rcu_expedited_wait() and places it in a new function named
synchronize_rcu_expedited_stall(). This is strictly a code-movement
commit. A later commit will use this reorganization to avoid printing
expedited RCU CPU stall warnings while there are ongoing CSD-lock stall
reports.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
During CSD-lock stalls, the additional information output by RCU CPU
stall warnings is usually redundant, flooding the console for not good
reason. However, this has been the way things work for a few years.
This commit therefore adds an rcutree.csd_lock_suppress_rcu_stall kernel
boot parameter that causes RCU CPU stall warnings to be abbreviated to
a single line when there is at least one CPU that has been stuck waiting
for CSD lock for more than five seconds.
To make this abbreviated message happen with decent probability:
tools/testing/selftests/rcutorture/bin/kvm.sh --allcpus --duration 8 \
--configs "2*TREE01" --kconfig "CONFIG_CSD_LOCK_WAIT_DEBUG=y" \
--bootargs "csdlock_debug=1 rcutorture.stall_cpu=200 \
rcutorture.stall_cpu_holdoff=120 rcutorture.stall_cpu_irqsoff=1 \
rcutree.csd_lock_suppress_rcu_stall=1 \
rcupdate.rcu_exp_cpu_stall_timeout=5000" --trust-make
[ paulmck: Apply kernel test robot feedback. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
About 40% of all csd_lock warnings observed in our fleet appear to
be due to sched_clock() going backward in time (usually only a little
bit), resulting in ts0 being larger than ts2.
When the local CPU is at fault, we should print out a message reflecting
that, rather than trying to get the remote CPU's stack trace.
Signed-off-by: Rik van Riel <riel@surriel.com>
Tested-by: "Paul E. McKenney" <paulmck@kernel.org>
Signed-off-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
Currently, the CSD-lock diagnostics in CONFIG_CSD_LOCK_WAIT_DEBUG=y
kernels are emitted at five-second intervals. Although this has proven
to be a good time interval for the first diagnostic, if the target CPU
keeps interrupts disabled for way longer than five seconds, the ratio
of useful new information to pointless repetition increases considerably.
Therefore, back off the time period for repeated reports of the same
incident, increasing linearly with the number of reports and logarithmicly
with the number of online CPUs.
[ paulmck: Apply Dan Carpenter feedback. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Imran Khan <imran.f.khan@oracle.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Leonardo Bras <leobras@redhat.com>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Reviewed-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
If a CSD-lock stall goes on long enough, it will cause an RCU CPU
stall warning. This additional warning provides much additional
console-log traffic and little additional information. Therefore,
provide a new csd_lock_is_stuck() function that returns true if there
is an ongoing CSD-lock stall. This function will be used by the RCU
CPU stall warnings to provide a one-line indication of the stall when
this function returns true.
[ neeraj.upadhyay: Apply Rik van Riel feedback. ]
[ neeraj.upadhyay: Apply kernel test robot feedback. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Imran Khan <imran.f.khan@oracle.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Leonardo Bras <leobras@redhat.com>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Signed-off-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
Because the testunit can start tests in the future via the DELAY
register, it may happen that a command is still pending. Support
detecting that by returning the number of a command in progress (if
there is one).
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
For some devices, it is essential that controllers handle repeated start
correctly and do not replace it with a stop/start combination. This
addition helps to test that because it will only return a version string
if repeated start is done properly.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Sometimes decimal values are just shorter (like for cmds), sometimes
they are even easier to understand (like for the delay value). Make use
of them.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Because a 'fallthrough' was refactored away, the order of 'case'
statements can be sorted better now to ease understanding the flow of
events.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
There is already a check for 'asid > MAX_ASID_AVAILABLE' in kern_pcid(), so
it is unnecessary to perform this check in build_cr3() right before calling
kern_pcid().
Remove it.
Signed-off-by: Yuntao Wang <yuntao.wang@linux.dev>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20240814124645.51019-1-yuntao.wang@linux.dev
There are two distinct CPU features related to the use of XSAVES and LBR:
whether LBR is itself supported and whether XSAVES supports LBR. The LBR
subsystem correctly checks both in intel_pmu_arch_lbr_init(), but the
XSTATE subsystem does not.
The LBR bit is only removed from xfeatures_mask_independent when LBR is not
supported by the CPU, but there is no validation of XSTATE support.
If XSAVES does not support LBR the write to IA32_XSS causes a #GP fault,
leaving the state of IA32_XSS unchanged, i.e. zero. The fault is handled
with a warning and the boot continues.
Consequently the next XRSTORS which tries to restore supervisor state fails
with #GP because the RFBM has zero for all supervisor features, which does
not match the XCOMP_BV field.
As XFEATURE_MASK_FPSTATE includes supervisor features setting up the FPU
causes a #GP, which ends up in fpu_reset_from_exception_fixup(). That fails
due to the same problem resulting in recursive #GPs until the kernel runs
out of stack space and double faults.
Prevent this by storing the supported independent features in
fpu_kernel_cfg during XSTATE initialization and use that cached value for
retrieving the independent feature bits to be written into IA32_XSS.
[ tglx: Massaged change log ]
Fixes: f0dccc9da4 ("x86/fpu/xstate: Support dynamic supervisor feature for LBR")
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Mitchell Levy <levymitchell0@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20240812-xsave-lbr-fix-v3-1-95bac1bf62f4@gmail.com
Replace IS_ENABLED() with IS_REACHABLE() to substitute empty stubs for:
i2c_acpi_get_i2c_resource()
i2c_acpi_client_count()
i2c_acpi_find_bus_speed()
i2c_acpi_new_device_by_fwnode()
i2c_adapter *i2c_acpi_find_adapter_by_handle()
i2c_acpi_waive_d0_probe()
commit f17c06c660 ("i2c: Fix conditional for substituting empty ACPI
functions") partially fixed this conditional to depend on CONFIG_I2C,
but used IS_ENABLED(), which is wrong since CONFIG_I2C is tristate.
CONFIG_ACPI is boolean but let's also change it to use IS_REACHABLE()
to future-proof it against becoming tristate.
Somehow despite testing various combinations of CONFIG_I2C and CONFIG_ACPI
we missed the combination CONFIG_I2C=m, CONFIG_ACPI=y.
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Fixes: f17c06c660 ("i2c: Fix conditional for substituting empty ACPI functions")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202408141333.gYnaitcV-lkp@intel.com/
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Use scoped for_each_available_child_of_node_scoped() when iterating over
device nodes to make code a bit simpler.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://patch.msgid.link/20240814143805.98874-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
0 is incorrect error code when failed to parse and map IRQ.
Replace OF specific old API for IRQ retrieval with a generic
one to fix this issue.
Fixes: 0f245463b0 ("spi: ppc4xx: handle irq_of_parse_and_map() errors")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20240814144525.2648450-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Zero and negative number is not a valid IRQ for in-kernel code and the
irq_of_parse_and_map() function returns zero on error. So this check for
valid IRQs should only accept values > 0.
Fixes: 44dab88e7c ("spi: add spi_ppc4xx driver")
Signed-off-by: Ma Ke <make24@iscas.ac.cn>
Link: https://patch.msgid.link/20240722141822.1052370-1-make24@iscas.ac.cn
Signed-off-by: Mark Brown <broonie@kernel.org>
Its necessary to call pm_runtime_force_*() hooks as part of system
suspend/resume calls so that the runtime_pm hooks get called. This
ensures latest state of the IP is cached and restored during system
sleep. This is especially true if runtime autosuspend is enabled as
runtime suspend hooks may not be called at all before system sleeps.
Without this patch, OSPI NOR enumeration (READ_ID) fails during resume
as context saved during suspend path is inconsistent.
Fixes: 078d62de43 ("spi: cadence-qspi: add system-wide suspend and resume callbacks")
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://patch.msgid.link/20240814151237.3856184-1-vigneshr@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Add support for the swctrl-gpios property which contains the phandle to
the GPIO indicating the clock supply to the BT module.
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Link: https://patch.msgid.link/20240813185827.154779-3-brgl@bgdev.pl
Signed-off-by: Mark Brown <broonie@kernel.org>
The Bluetooth module is obviously not an ath11k so drop the word.
Fixes: b5cb34c93b ("regulator: dt-bindings: describe the PMU module of the QCA6390 package")
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Link: https://patch.msgid.link/20240813185827.154779-1-brgl@bgdev.pl
Signed-off-by: Mark Brown <broonie@kernel.org>
Obtain the device node reference with scoped/cleanup.h and use scoped
for_each_child_of_node_scoped() to reduce error handling and make the
code a bit simpler. Add also brackets {} over outer for loop for code
readability.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://patch.msgid.link/20240814-cleanup-h-of-node-put-regulator-v1-2-87151088b883@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
soc-pcm.c has snd_soc_dpcm_stream_{lock/unlock}_irq() helper function,
but it is almost nothing help. It just makes a code complex.
Let's remove it.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://patch.msgid.link/875xsnll85.wl-kuninori.morimoto.gx@renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Replace SET_RUNTIME_PM_OPS()/SET SYSTEM_SLEEP_PM_OPS() with their modern
RUNTIME_PM_OPS() and SYSTEM_SLEEP_PM_OPS() alternatives.
The combined usage of pm_ptr() and RUNTIME_PM_OPS/SYSTEM_SLEEP_PM_OPS()
allows the compiler to evaluate if the runtime suspend/resume() functions
are used at build time or are simply dead code.
This allows removing the CONFIG_PM ifdefery from the runtime
suspend/resume() functions.
Signed-off-by: Fabio Estevam <festevam@denx.de>
Link: https://patch.msgid.link/20240808184944.267686-7-festevam@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Replace SET_SYSTEM_SLEEP_PM_OPS() with its modern SYSTEM_SLEEP_PM_OPS()
alternative.
The combined usage of pm_sleep_ptr() and SYSTEM_SLEEP_PM_OPS() allows
the compiler to evaluate if the suspend/resume() functions
are used at build time or are simply dead code.
This allows removing the CONFIG_PM_SLEEP ifdefery from the
suspend/resume() functions.
Signed-off-by: Fabio Estevam <festevam@denx.de>
Link: https://patch.msgid.link/20240808184944.267686-6-festevam@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Replace SET_SYSTEM_SLEEP_PM_OPS() with its modern SYSTEM_SLEEP_PM_OPS()
alternative.
The combined usage of pm_sleep_ptr() and SYSTEM_SLEEP_PM_OPS() allows
the compiler to evaluate if the suspend/resume() functions are used at
build time or are simply dead code.
This allows removing the CONFIG_PM_SLEEP ifdefery from the
suspend/resume() functions.
Signed-off-by: Fabio Estevam <festevam@denx.de>
Link: https://patch.msgid.link/20240808184944.267686-5-festevam@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Replace SET_RUNTIME_PM_OPS()/SET SYSTEM_SLEEP_PM_OPS() with their modern
RUNTIME_PM_OPS() and SYSTEM_SLEEP_PM_OPS() alternatives.
The combined usage of pm_ptr() and RUNTIME_PM_OPS/SYSTEM_SLEEP_PM_OPS()
allows the compiler to evaluate if the runtime suspend/resume() functions
are used at build time or are simply dead code.
This allows removing the CONFIG_PM ifdefery from the runtime
suspend/resume() functions.
Signed-off-by: Fabio Estevam <festevam@denx.de>
Link: https://patch.msgid.link/20240808184944.267686-4-festevam@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Replace SET_RUNTIME_PM_OPS() with its modern RUNTIME_PM_OPS()
alternative.
The combined usage of pm_ptr() and RUNTIME_PM_OPS() allows the
compiler to evaluate if the runtime suspend/resume() functions
are used at build time or are simply dead code.
This allows removing the CONFIG_PM ifdefery from the runtime
suspend/resume() functions.
Signed-off-by: Fabio Estevam <festevam@denx.de>
Link: https://patch.msgid.link/20240808184944.267686-3-festevam@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Replace SET_RUNTIME_PM_OPS()/SET SYSTEM_SLEEP_PM_OPS() with their modern
RUNTIME_PM_OPS() and SYSTEM_SLEEP_PM_OPS() alternatives.
The combined usage of pm_ptr() and RUNTIME_PM_OPS/SYSTEM_SLEEP_PM_OPS()
allows the compiler to evaluate if the runtime suspend/resume() functions
are used at build time or are simply dead code.
This allows removing the CONFIG_PM ifdefery from the runtime
suspend/resume() functions.
Signed-off-by: Fabio Estevam <festevam@denx.de>
Link: https://patch.msgid.link/20240808184944.267686-2-festevam@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Replace SET_RUNTIME_PM_OPS()/SET SYSTEM_SLEEP_PM_OPS() with their modern
RUNTIME_PM_OPS() and SYSTEM_SLEEP_PM_OPS() alternatives.
The combined usage of pm_ptr() and RUNTIME_PM_OPS/SYSTEM_SLEEP_PM_OPS()
allows the compiler to evaluate if the runtime suspend/resume() functions
are used at build time or are simply dead code.
This allows removing the CONFIG_PM ifdefery from the runtime
suspend/resume() functions.
Signed-off-by: Fabio Estevam <festevam@denx.de>
Link: https://patch.msgid.link/20240808184944.267686-1-festevam@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The device never comes online from a reset/shutdown state, because the
driver de-asserts reset GPIO when requesting it but then, at the end of
probe() through wcd937x_reset(), leaves it asserted.
Cc: stable@vger.kernel.org
Fixes: 9be3ec196d ("ASoC: codecs: wcd937x: add wcd937x codec driver")
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://patch.msgid.link/20240806114913.40022-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
"INVALID" is misspelt in "SEV_RET_INAVLID_CONFIG". Since this is part of
the UAPI, keep the current definition and add a new one with the fix.
Fix-suggested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Amit Shah <amit.shah@amd.com>
Message-ID: <20240814083113.21622-1-amit@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In load_elf_binary as part of the execve(), when the current
task’s personality has MMAP_PAGE_ZERO set, the kernel allocates
one page at address 0. According to the comment:
/* Why this, you ask??? Well SVr4 maps page 0 as read-only,
and some applications "depend" upon this behavior.
Since we do not have the power to recompile these, we
emulate the SVr4 behavior. Sigh. */
At one point, Linus suggested removing this [1].
Code search in debian didn't see much use of MMAP_PAGE_ZERO [2],
it exists in util and test (rr).
Sealing this is probably safe, the comment doesn't say
the app ever wanting to change the mapping to rwx. Sealing
also ensures that never happens.
If there is a complaint, we can make this configurable.
Link: https://lore.kernel.org/lkml/CAHk-=whVa=nm_GW=NVfPHqcxDbWt4JjjK1YWb0cLjO4ZSGyiDA@mail.gmail.com/ [1]
Link: https://codesearch.debian.net/search?q=MMAP_PAGE_ZERO&literal=1&perpkg=1&page=1 [2]
Signed-off-by: Jeff Xu <jeffxu@chromium.org>
Link: https://lore.kernel.org/r/20240806214931.2198172-2-jeffxu@google.com
Signed-off-by: Kees Cook <kees@kernel.org>
Currently, only acpi_early_node_map[0] was initialized to NUMA_NO_NODE.
To ensure all the values were properly initialized, switch to initialize
all of them to NUMA_NO_NODE.
Fixes: e189624916 ("arm64: numa: rework ACPI NUMA initialization")
Cc: <stable@vger.kernel.org> # 4.19.x
Reported-by: Andrew Jones <ajones@ventanamicro.com>
Suggested-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Haibo Xu <haibo1.xu@intel.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Sunil V L <sunilvl@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
Link: https://lore.kernel.org/r/853d7f74aa243f6f5999e203246f0d1ae92d2b61.1722828421.git.haibo1.xu@intel.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
In the CONFIG_CC_HAS_ASM_GOTO_OUTPUT=y version of __get_mem_asm(), we
incorrectly use _ASM_EXTABLE_##type##ACCESS_ERR() such that upon a fault
the extable fixup handler writes -EFAULT into "%w0", which is the
register containing 'x' (the result of the load).
This was a thinko in commit:
86a6a68feb ("arm64: start using 'asm goto' for get_user() when available")
Prior to that commit _ASM_EXTABLE_##type##ACCESS_ERR_ZERO() was used
such that the extable fixup handler wrote -EFAULT into "%w0" (the
register containing 'err'), and zero into "%w1" (the register containing
'x'). When the 'err' variable was removed, the extable entry was updated
incorrectly.
Writing -EFAULT to the value register is unnecessary but benign:
* We never want -EFAULT in the value register, and previously this would
have been zeroed in the extable fixup handler.
* In __get_user_error() the value is overwritten with zero explicitly in
the error path.
* The asm goto outputs cannot be used when the goto label is taken, as
older compilers (e.g. clang < 16.0.0) do not guarantee that asm goto
outputs are usable in this path and may use a stale value rather than
the value in an output register. Consequently, zeroing in the extable
fixup handler is insufficient to ensure callers see zero in the error
path.
* The expected usage of unsafe_get_user() and get_kernel_nofault()
requires that the value is not consumed in the error path.
Some versions of GCC would mis-compile asm goto with outputs, and
erroneously omit subsequent assignments, breaking the error path
handling in __get_user_error(). This was discussed at:
https://lore.kernel.org/lkml/ZpfxLrJAOF2YNqCk@J2N7QTR9R3.cambridge.arm.com/
... and was fixed by removing support for asm goto with outputs on those
broken compilers in commit:
f2f6a8e887 ("init/Kconfig: remove CONFIG_GCC_ASM_GOTO_OUTPUT_WORKAROUND")
With that out of the way, we can safely replace the usage of
_ASM_EXTABLE_##type##ACCESS_ERR() with _ASM_EXTABLE_##type##ACCESS(),
leaving the value register unchanged in the case a fault is taken, as
was originally intended. This matches other architectures and matches
our __put_mem_asm().
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20240807103731.2498893-1-mark.rutland@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Add a new user option to memslot_perf_test to allow testing memslot move
with quirk KVM_X86_QUIRK_SLOT_ZAP_ALL disabled.
Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
Message-ID: <20240703021219.13939-1-yan.y.zhao@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add a new user option to memslot_modification_stress_test to allow testing
with slot zap quirk KVM_X86_QUIRK_SLOT_ZAP_ALL disabled.
Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
Message-ID: <20240703021206.13923-1-yan.y.zhao@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Update set_memory_region_test to make sure memslot move and deletion
function correctly both when slot zap quirk KVM_X86_QUIRK_SLOT_ZAP_ALL is
enabled and disabled.
Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
Message-ID: <20240703021119.13904-1-yan.y.zhao@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Introduce the quirk KVM_X86_QUIRK_SLOT_ZAP_ALL to allow users to select
KVM's behavior when a memslot is moved or deleted for KVM_X86_DEFAULT_VM
VMs. Make sure KVM behave as if the quirk is always disabled for
non-KVM_X86_DEFAULT_VM VMs.
The KVM_X86_QUIRK_SLOT_ZAP_ALL quirk offers two behavior options:
- when enabled: Invalidate/zap all SPTEs ("zap-all"),
- when disabled: Precisely zap only the leaf SPTEs within the range of the
moving/deleting memory slot ("zap-slot-leafs-only").
"zap-all" is today's KVM behavior to work around a bug [1] where the
changing the zapping behavior of memslot move/deletion would cause VM
instability for VMs with an Nvidia GPU assigned; while
"zap-slot-leafs-only" allows for more precise zapping of SPTEs within the
memory slot range, improving performance in certain scenarios [2], and
meeting the functional requirements for TDX.
Previous attempts to select "zap-slot-leafs-only" include a per-VM
capability approach [3] (which was not preferred because the root cause of
the bug remained unidentified) and a per-memslot flag approach [4]. Sean
and Paolo finally recommended the implementation of this quirk and
explained that it's the least bad option [5].
By default, the quirk is enabled on KVM_X86_DEFAULT_VM VMs to use
"zap-all". Users have the option to disable the quirk to select
"zap-slot-leafs-only" for specific KVM_X86_DEFAULT_VM VMs that are
unaffected by this bug.
For non-KVM_X86_DEFAULT_VM VMs, the "zap-slot-leafs-only" behavior is
always selected without user's opt-in, regardless of if the user opts for
"zap-all".
This is because it is assumed until proven otherwise that non-
KVM_X86_DEFAULT_VM VMs will not be exposed to the bug [1], and most
importantly, it's because TDX must have "zap-slot-leafs-only" always
selected. In TDX's case a memslot's GPA range can be a mixture of "private"
or "shared" memory. Shared is roughly analogous to how EPT is handled for
normal VMs, but private GPAs need lots of special treatment:
1) "zap-all" would require to zap private root page or non-leaf entries or
at least leaf-entries beyond the deleting memslot scope. However, TDX
demands that the root page of the private page table remains unchanged,
with leaf entries being zapped before non-leaf entries, and any dropped
private guest pages must be re-accepted by the guest.
2) if "zap-all" zaps only shared page tables, it would result in private
pages still being mapped when the memslot is gone. This may affect even
other processes if later the gmem fd was whole punched, causing the
pages being freed on the host while still mapped in the TD, because
there's no pgoff to the gfn information to zap the private page table
after memslot is gone.
So, simply go "zap-slot-leafs-only" as if the quirk is always disabled for
non-KVM_X86_DEFAULT_VM VMs to avoid manual opt-in for every VM type [6] or
complicating quirk disabling interface (current quirk disabling interface
is limited, no way to query quirks, or force them to be disabled).
Add a new function kvm_mmu_zap_memslot_leafs() to implement
"zap-slot-leafs-only". This function does not call kvm_unmap_gfn_range(),
bypassing special handling to APIC_ACCESS_PAGE_PRIVATE_MEMSLOT, as
1) The APIC_ACCESS_PAGE_PRIVATE_MEMSLOT cannot be created by users, nor can
it be moved. It is only deleted by KVM when APICv is permanently
inhibited.
2) kvm_vcpu_reload_apic_access_page() effectively does nothing when
APIC_ACCESS_PAGE_PRIVATE_MEMSLOT is deleted.
3) Avoid making all cpus request of KVM_REQ_APIC_PAGE_RELOAD can save on
costly IPIs.
Suggested-by: Kai Huang <kai.huang@intel.com>
Suggested-by: Sean Christopherson <seanjc@google.com>
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Link: https://patchwork.kernel.org/project/kvm/patch/20190205210137.1377-11-sean.j.christopherson@intel.com [1]
Link: https://patchwork.kernel.org/project/kvm/patch/20190205210137.1377-11-sean.j.christopherson@intel.com/#25054908 [2]
Link: https://lore.kernel.org/kvm/20200713190649.GE29725@linux.intel.com/T/#mabc0119583dacf621025e9d873c85f4fbaa66d5c [3]
Link: https://lore.kernel.org/all/20240515005952.3410568-3-rick.p.edgecombe@intel.com [4]
Link: https://lore.kernel.org/all/7df9032d-83e4-46a1-ab29-6c7973a2ab0b@redhat.com [5]
Link: https://lore.kernel.org/all/ZnGa550k46ow2N3L@google.com [6]
Co-developed-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
Message-ID: <20240703021043.13881-1-yan.y.zhao@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Disallow read-only memslots for SEV-{ES,SNP} VM types, as KVM can't
directly emulate instructions for ES/SNP, and instead the guest must
explicitly request emulation. Unless the guest explicitly requests
emulation without accessing memory, ES/SNP relies on KVM creating an MMIO
SPTE, with the subsequent #NPF being reflected into the guest as a #VC.
But for read-only memslots, KVM deliberately doesn't create MMIO SPTEs,
because except for ES/SNP, doing so requires setting reserved bits in the
SPTE, i.e. the SPTE can't be readable while also generating a #VC on
writes. Because KVM never creates MMIO SPTEs and jumps directly to
emulation, the guest never gets a #VC. And since KVM simply resumes the
guest if ES/SNP guests trigger emulation, KVM effectively puts the vCPU
into an infinite #NPF loop if the vCPU attempts to write read-only memory.
Disallow read-only memory for all VMs with protected state, i.e. for
upcoming TDX VMs as well as ES/SNP VMs. For TDX, it's actually possible
to support read-only memory, as TDX uses EPT Violation #VE to reflect the
fault into the guest, e.g. KVM could configure read-only SPTEs with RX
protections and SUPPRESS_VE=0. But there is no strong use case for
supporting read-only memslots on TDX, e.g. the main historical usage is
to emulate option ROMs, but TDX disallows executing from shared memory.
And if someone comes along with a legitimate, strong use case, the
restriction can always be lifted for TDX.
Don't bother trying to retroactively apply the restriction to SEV-ES
VMs that are created as type KVM_X86_DEFAULT_VM. Read-only memslots can't
possibly work for SEV-ES, i.e. disallowing such memslots is really just
means reporting an error to userspace instead of silently hanging vCPUs.
Trying to deal with the ordering between KVM_SEV_INIT and memslot creation
isn't worth the marginal benefit it would provide userspace.
Fixes: 26c44aa9e0 ("KVM: SEV: define VM types for SEV and SEV-ES")
Fixes: 1dfe571c12 ("KVM: SEV: Add initial SEV-SNP support")
Cc: Peter Gonda <pgonda@google.com>
Cc: Michael Roth <michael.roth@amd.com>
Cc: Vishal Annapurve <vannapurve@google.com>
Cc: Ackerly Tng <ackerleytng@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20240809190319.1710470-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Merge tag 'selinux-pr-20240814' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux
Pull selinux fixes from Paul Moore:
- Fix a xperms counting problem where we adding to the xperms count
even if we failed to add the xperm.
- Propogate errors from avc_add_xperms_decision() back to the caller so
that we can trigger the proper cleanup and error handling.
- Revert our use of vma_is_initial_heap() in favor of our older logic
as vma_is_initial_heap() doesn't correctly handle the no-heap case
and it is causing issues with the SELinux process/execheap access
control. While the older SELinux logic may not be perfect, it
restores the expected user visible behavior.
Hopefully we will be able to resolve the problem with the
vma_is_initial_heap() macro with the mm folks, but we need to fix
this in the meantime.
* tag 'selinux-pr-20240814' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
selinux: revert our use of vma_is_initial_heap()
selinux: add the processing of the failure of avc_add_xperms_decision()
selinux: fix potential counting error in avc_add_xperms_decision()
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Merge tag 'vfs-6.11-rc4.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs fixes from Christian Brauner:
"VFS:
- Fix the name of file lease slab cache. When file leases were split
out of file locks the name of the file lock slab cache was used for
the file leases slab cache as well.
- Fix a type in take_fd() helper.
- Fix infinite directory iteration for stable offsets in tmpfs.
- When the icache is pruned all reclaimable inodes are marked with
I_FREEING and other processes that try to lookup such inodes will
block.
But some filesystems like ext4 can trigger lookups in their inode
evict callback causing deadlocks. Ext4 does such lookups if the
ea_inode feature is used whereby a separate inode may be used to
store xattrs.
Introduce I_LRU_ISOLATING which pins the inode while its pages are
reclaimed. This avoids inode deletion during inode_lru_isolate()
avoiding the deadlock and evict is made to wait until
I_LRU_ISOLATING is done.
netfs:
- Fault in smaller chunks for non-large folio mappings for
filesystems that haven't been converted to large folios yet.
- Fix the CONFIG_NETFS_DEBUG config option. The config option was
renamed a short while ago and that introduced two minor issues.
First, it depended on CONFIG_NETFS whereas it wants to depend on
CONFIG_NETFS_SUPPORT. The former doesn't exist, while the latter
does. Second, the documentation for the config option wasn't fixed
up.
- Revert the removal of the PG_private_2 writeback flag as ceph is
using it and fix how that flag is handled in netfs.
- Fix DIO reads on 9p. A program watching a file on a 9p mount
wouldn't see any changes in the size of the file being exported by
the server if the file was changed directly in the source
filesystem. Fix this by attempting to read the full size specified
when a DIO read is requested.
- Fix a NULL pointer dereference bug due to a data race where a
cachefiles cookies was retired even though it was still in use.
Check the cookie's n_accesses counter before discarding it.
nsfs:
- Fix ioctl declaration for NS_GET_MNTNS_ID from _IO() to _IOR() as
the kernel is writing to userspace.
pidfs:
- Prevent the creation of pidfds for kthreads until we have a
use-case for it and we know the semantics we want. It also confuses
userspace why they can get pidfds for kthreads.
squashfs:
- Fix an unitialized value bug reported by KMSAN caused by a
corrupted symbolic link size read from disk. Check that the
symbolic link size is not larger than expected"
* tag 'vfs-6.11-rc4.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
Squashfs: sanity check symbolic link size
9p: Fix DIO read through netfs
vfs: Don't evict inode under the inode lru traversing context
netfs: Fix handling of USE_PGPRIV2 and WRITE_TO_CACHE flags
netfs, ceph: Revert "netfs: Remove deprecated use of PG_private_2 as a second writeback flag"
file: fix typo in take_fd() comment
pidfd: prevent creation of pidfds for kthreads
netfs: clean up after renaming FSCACHE_DEBUG config
libfs: fix infinite directory reads for offset dir
nsfs: fix ioctl declaration
fs/netfs/fscache_cookie: add missing "n_accesses" check
filelock: fix name of file_lease slab cache
netfs: Fault in smaller chunks for non-large folio mappings
There is a confusing pattern in the kernel to use a variable named
'timeout' to store the result of wait_for_completion_timeout() causing
patterns like:
timeout = wait_for_completion_timeout(...)
if (!timeout) return -ETIMEDOUT;
with all kinds of permutations. Use 'time_left' as a variable to make the
code self explaining.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Michal Simek <michal.simek@amd.com>
Acked-by: Xu Yilun <yilun.xu@intel.com>
Link: https://lore.kernel.org/r/20240729104319.2658-2-wsa+renesas@sang-engineering.com
Signed-off-by: Xu Yilun <yilun.xu@linux.intel.com>
