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path: root/drivers/char/tpm
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2023-04-24tpm, tpm_tis: startup chip before testing for interruptsLino Sanfilippo
In tpm_tis_gen_interrupt() a request for a property value is sent to the TPM to test if interrupts are generated. However after a power cycle the TPM responds with TPM_RC_INITIALIZE which indicates that the TPM is not yet properly initialized. Fix this by first starting the TPM up before the request is sent. For this the startup implementation is removed from tpm_chip_register() and put into the new function tpm_chip_startup() which is called before the interrupts are tested. Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Tested-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-04-24tpm, tpm_tis: Claim locality when interrupts are reenabled on resumeLino Sanfilippo
In tpm_tis_resume() make sure that the locality has been claimed when tpm_tis_reenable_interrupts() is called. Otherwise the writings to the register might not have any effect. Fixes: 45baa1d1fa39 ("tpm_tis: Re-enable interrupts upon (S3) resume") Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Tested-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-04-24tpm, tpm_tis: Claim locality in interrupt handlerLino Sanfilippo
Writing the TPM_INT_STATUS register in the interrupt handler to clear the interrupts only has effect if a locality is held. Since this is not guaranteed at the time the interrupt is fired, claim the locality explicitly in the handler. Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Tested-by: Michael Niewöhner <linux@mniewoehner.de> Tested-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-04-24tpm, tpm_tis: Request threaded interrupt handlerLino Sanfilippo
The TIS interrupt handler at least has to read and write the interrupt status register. In case of SPI both operations result in a call to tpm_tis_spi_transfer() which uses the bus_lock_mutex of the spi device and thus must only be called from a sleepable context. To ensure this request a threaded interrupt handler. Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Tested-by: Michael Niewöhner <linux@mniewoehner.de> Tested-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-04-24tpm, tpm: Implement usage counter for localityLino Sanfilippo
Implement a usage counter for the (default) locality used by the TPM TIS driver: Request the locality from the TPM if it has not been claimed yet, otherwise only increment the counter. Also release the locality if the counter is 0 otherwise only decrement the counter. Since in case of SPI the register accesses are locked by means of the SPI bus mutex use a sleepable lock (i.e. also a mutex) to ensure thread-safety of the counter which may be accessed by both a userspace thread and the interrupt handler. By doing this refactor the names of the amended functions to use a more appropriate prefix. Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Tested-by: Michael Niewöhner <linux@mniewoehner.de> Tested-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-04-24tpm, tpm_tis: do not check for the active locality in interrupt handlerLino Sanfilippo
After driver initialization tpm_tis_data->locality may only be modified in case of a LOCALITY CHANGE interrupt. In this case the interrupt handler iterates over all localities only to assign the active one to tpm_tis_data->locality. However this information is never used any more, so the assignment is not needed. Furthermore without the assignment tpm_tis_data->locality cannot change any more at driver runtime, and thus no protection against concurrent modification is required when the variable is read at other places. So remove this iteration entirely. Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Tested-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-04-24tpm, tpm_tis: Move interrupt mask checks into own functionLino Sanfilippo
Clean up wait_for_tpm_stat() by moving multiple similar interrupt mask checks into an own function. Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Suggested-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-04-24tpm, tpm_tis: Only handle supported interruptsLino Sanfilippo
According to the TPM Interface Specification (TIS) support for "stsValid" and "commandReady" interrupts is only optional. This has to be taken into account when handling the interrupts in functions like wait_for_tpm_stat(). To determine the supported interrupts use the capability query. Also adjust wait_for_tpm_stat() to only wait for interrupt reported status changes. After that process all the remaining status changes by polling the status register. Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Tested-by: Michael Niewöhner <linux@mniewoehner.de> Tested-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-04-24tpm, tpm_tis: Claim locality before writing interrupt registersLino Sanfilippo
In tpm_tis_probe_single_irq() interrupt registers TPM_INT_VECTOR, TPM_INT_STATUS and TPM_INT_ENABLE are modified to setup the interrupts. Currently these modifications are done without holding a locality thus they have no effect. Fix this by claiming the (default) locality before the registers are written. Since now tpm_tis_gen_interrupt() is called with the locality already claimed remove locality request and release from this function. Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Tested-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-04-24tpm, tpm_tis: Do not skip reset of original interrupt vectorLino Sanfilippo
If in tpm_tis_probe_irq_single() an error occurs after the original interrupt vector has been read, restore the interrupts before the error is returned. Since the caller does not check the error value, return -1 in any case that the TPM_CHIP_FLAG_IRQ flag is not set. Since the return value of function tpm_tis_gen_interrupt() is not longer used, make it a void function. Fixes: 1107d065fdf1 ("tpm_tis: Introduce intermediate layer for TPM access") Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Tested-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-04-24tpm, tpm_tis: Disable interrupts if tpm_tis_probe_irq() failedLino Sanfilippo
Both functions tpm_tis_probe_irq_single() and tpm_tis_probe_irq() may setup the interrupts and then return with an error. This case is indicated by a missing TPM_CHIP_FLAG_IRQ flag in chip->flags. Currently the interrupt setup is only undone if tpm_tis_probe_irq_single() fails. Undo the setup also if tpm_tis_probe_irq() fails. Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Tested-by: Michael Niewöhner <linux@mniewoehner.de> Tested-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-04-24tpm, tpm_tis: Claim locality before writing TPM_INT_ENABLE registerLino Sanfilippo
In disable_interrupts() the TPM_GLOBAL_INT_ENABLE bit is unset in the TPM_INT_ENABLE register to shut the interrupts off. However modifying the register is only possible with a held locality. So claim the locality before disable_interrupts() is called. Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Tested-by: Michael Niewöhner <linux@mniewoehner.de> Tested-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-04-24tpm, tpm_tis: Avoid cache incoherency in test for interruptsLino Sanfilippo
The interrupt handler that sets the boolean variable irq_tested may run on another CPU as the thread that checks irq_tested as part of the irq test in tpm_tis_send(). Since nothing guarantees cache coherency between CPUs for unsynchronized accesses to boolean variables the testing thread might not perceive the value change done in the interrupt handler. Avoid this issue by setting the bit TPM_TIS_IRQ_TESTED in the flags field of the tpm_tis_data struct and by accessing this field with the bit manipulating functions that provide cache coherency. Also convert all other existing sites to use the proper macros when accessing this bitfield. Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com> Tested-by: Michael Niewöhner <linux@mniewoehner.de> Tested-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-04-24tpm: remove unnecessary (void*) conversionsYu Zhe
Pointer variables of void * type do not require type cast. Signed-off-by: Yu Zhe <yuzhe@nfschina.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-04-24tpm: cr50: i2c: use jiffies to wait for tpm ready irqMark Hasemeyer
When waiting for a tpm ready completion, the cr50 i2c driver incorrectly assumes that the value of timeout_a is represented in milliseconds instead of jiffies. Remove the msecs_to_jiffies conversion. Signed-off-by: Mark Hasemeyer <markhas@chromium.org> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-04-06tpm: atmel: Add explicit include for of.hRob Herring
With linux/acpi.h (in linux/tpm.h) no longer implicitly including of.h, add an explicit include of of.h to fix the following errors: drivers/char/tpm/tpm_atmel.h:50:14: error: implicit declaration of function 'of_find_node_by_name'; did you mean 'bus_find_device_by_name'? [-Werror=implicit-function-declaration] drivers/char/tpm/tpm_atmel.h:50:12: error: assignment to 'struct device_node *' from 'int' makes pointer from integer without a cast [-Werror=int-conversion] drivers/char/tpm/tpm_atmel.h:55:14: error: implicit declaration of function 'of_device_is_compatible'; did you mean 'fwnode_device_is_compatible'? [-Werror=implicit-function-declaration] ... Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Rob Herring <robh@kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-04-03Merge 6.3-rc5 into driver-core-nextGreg Kroah-Hartman
We need the fixes in here for testing, as well as the driver core changes for documentation updates to build on. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-21tpm: Fix a possible dereference of ERR_PTR in tpm_init()Harshit Mogalapalli
Smatch reports: drivers/char/tpm/tpm-interface.c:470 tpm_init() error: 'tpm_class' dereferencing possible ERR_PTR() If class_create() returns error pointer, we are dereferencing a possible error pointer. Fix this by moving the dereference post error handling. Fixes: a010eb881243 ("tpm: fix up the tpm_class shutdown_pre pointer when created") Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com> Link: https://lore.kernel.org/r/20230321061416.626561-1-harshit.m.mogalapalli@oracle.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-17tpm: fix up the tpm_class shutdown_pre pointer when createdGreg Kroah-Hartman
Do not wait until long after the struct class has been created to set the shutdown_pre pointer for the tpm_class, assign it right away. This is the only in-kernel offender that tries to modify the device->class pointer contents after it has been assigned to a device, so fix that up by doing the function pointer assignment before it is matched with the device. Because of this, the patch should go through the driver core tree to allow later changes to struct device to be possible. Cc: Peter Huewe <peterhuewe@gmx.de> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: linux-integrity@vger.kernel.org Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Link: https://lore.kernel.org/r/20230313181843.1207845-10-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-17driver core: class: remove module * from class_create()Greg Kroah-Hartman
The module pointer in class_create() never actually did anything, and it shouldn't have been requred to be set as a parameter even if it did something. So just remove it and fix up all callers of the function in the kernel tree at the same time. Cc: "Rafael J. Wysocki" <rafael@kernel.org> Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Link: https://lore.kernel.org/r/20230313181843.1207845-4-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-12tpm: disable hwrng for fTPM on some AMD designsMario Limonciello
AMD has issued an advisory indicating that having fTPM enabled in BIOS can cause "stuttering" in the OS. This issue has been fixed in newer versions of the fTPM firmware, but it's up to system designers to decide whether to distribute it. This issue has existed for a while, but is more prevalent starting with kernel 6.1 because commit b006c439d58db ("hwrng: core - start hwrng kthread also for untrusted sources") started to use the fTPM for hwrng by default. However, all uses of /dev/hwrng result in unacceptable stuttering. So, simply disable registration of the defective hwrng when detecting these faulty fTPM versions. As this is caused by faulty firmware, it is plausible that such a problem could also be reproduced by other TPM interactions, but this hasn't been shown by any user's testing or reports. It is hypothesized to be triggered more frequently by the use of the RNG because userspace software will fetch random numbers regularly. Intentionally continue to register other TPM functionality so that users that rely upon PCR measurements or any storage of data will still have access to it. If it's found later that another TPM functionality is exacerbating this problem a module parameter it can be turned off entirely and a module parameter can be introduced to allow users who rely upon fTPM functionality to turn it on even though this problem is present. Link: https://www.amd.com/en/support/kb/faq/pa-410 Link: https://bugzilla.kernel.org/show_bug.cgi?id=216989 Link: https://lore.kernel.org/all/20230209153120.261904-1-Jason@zx2c4.com/ Fixes: b006c439d58d ("hwrng: core - start hwrng kthread also for untrusted sources") Cc: stable@vger.kernel.org Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Thorsten Leemhuis <regressions@leemhuis.info> Cc: James Bottomley <James.Bottomley@hansenpartnership.com> Tested-by: reach622@mailcuk.com Tested-by: Bell <1138267643@qq.com> Co-developed-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-03-12tpm/eventlog: Don't abort tpm_read_log on faulty ACPI addressMorten Linderud
tpm_read_log_acpi() should return -ENODEV when no eventlog from the ACPI table is found. If the firmware vendor includes an invalid log address we are unable to map from the ACPI memory and tpm_read_log() returns -EIO which would abort discovery of the eventlog. Change the return value from -EIO to -ENODEV when acpi_os_map_iomem() fails to map the event log. The following hardware was used to test this issue: Framework Laptop (Pre-production) BIOS: INSYDE Corp, Revision: 3.2 TPM Device: NTC, Firmware Revision: 7.2 Dump of the faulty ACPI TPM2 table: [000h 0000 4] Signature : "TPM2" [Trusted Platform Module hardware interface Table] [004h 0004 4] Table Length : 0000004C [008h 0008 1] Revision : 04 [009h 0009 1] Checksum : 2B [00Ah 0010 6] Oem ID : "INSYDE" [010h 0016 8] Oem Table ID : "TGL-ULT" [018h 0024 4] Oem Revision : 00000002 [01Ch 0028 4] Asl Compiler ID : "ACPI" [020h 0032 4] Asl Compiler Revision : 00040000 [024h 0036 2] Platform Class : 0000 [026h 0038 2] Reserved : 0000 [028h 0040 8] Control Address : 0000000000000000 [030h 0048 4] Start Method : 06 [Memory Mapped I/O] [034h 0052 12] Method Parameters : 00 00 00 00 00 00 00 00 00 00 00 00 [040h 0064 4] Minimum Log Length : 00010000 [044h 0068 8] Log Address : 000000004053D000 Fixes: 0cf577a03f21 ("tpm: Fix handling of missing event log") Tested-by: Erkki Eilonen <erkki@bearmetal.eu> Signed-off-by: Morten Linderud <morten@linderud.pw> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-02-13tpm: add vendor flag to command code validationJulien Gomes
Some TPM 2.0 devices have support for additional commands which are not part of the TPM 2.0 specifications. These commands are identified with bit 29 of the 32 bits command codes. Contrarily to other fields of the TPMA_CC spec structure used to list available commands, the Vendor flag also has to be present in the command code itself (TPM_CC) when called. Add this flag to tpm_find_cc() mask to prevent blocking vendor command codes that can actually be supported by the underlying TPM device. Signed-off-by: Julien Gomes <julien@arista.com> Tested-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-02-13tpm: Add reserved memory event logEddie James
Some platforms may desire to pass the event log up to Linux in the form of a reserved memory region. In particular, this is desirable for embedded systems or baseboard management controllers (BMCs) booting with U-Boot. IBM OpenBMC BMCs will be the first user. Add support for the reserved memory in the TPM core to find the region and map it. Signed-off-by: Eddie James <eajames@linux.ibm.com> [jarkko: removed spurious dev_info()'s from tpm_read_log_memory_region()] Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> [yang: return -ENOMEM when devm_memremap() fails] Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-02-13tpm: Use managed allocation for bios event logEddie James
Since the bios event log is freed in the device release function, let devres handle the deallocation. This will allow other memory allocation/mapping functions to be used for the bios event log. Signed-off-by: Eddie James <eajames@linux.ibm.com> Tested-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-02-13tpm: tis_i2c: Convert to i2c's .probe_new()Uwe Kleine-König
The probe function doesn't make use of the i2c_device_id * parameter so it can be trivially converted. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-02-13tpm: tpm_i2c_nuvoton: Convert to i2c's .probe_new()Uwe Kleine-König
.probe_new() doesn't get the i2c_device_id * parameter, so determine that explicitly in the probe function. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-02-13tpm: tpm_i2c_infineon: Convert to i2c's .probe_new()Uwe Kleine-König
The probe function doesn't make use of the i2c_device_id * parameter so it can be trivially converted. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-02-13tpm: tpm_i2c_atmel: Convert to i2c's .probe_new()Uwe Kleine-König
The probe function doesn't make use of the i2c_device_id * parameter so it can be trivially converted. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-02-13tpm: st33zp24: Convert to i2c's .probe_new()Uwe Kleine-König
The probe function doesn't make use of the i2c_device_id * parameter so it can be trivially converted. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-02-13tpm_crb: Add support for CRB devices based on PlutonMatthew Garrett
Pluton is an integrated security processor present in some recent Ryzen parts. If it's enabled, it presents two devices - an MSFT0101 ACPI device that's broadly an implementation of a Command Response Buffer TPM2, and an MSFT0200 ACPI device whose functionality I haven't examined in detail yet. This patch only attempts to add support for the TPM device. There's a few things that need to be handled here. The first is that the TPM2 ACPI table uses a previously undefined start method identifier. The table format appears to include 16 bytes of startup data, which corresponds to one 64-bit address for a start message and one 64-bit address for a completion response. The second is that the ACPI tables on the Thinkpad Z13 I'm testing this on don't define any memory windows in _CRS (or, more accurately, there are two empty memory windows). This check doesn't seem strictly necessary, so I've skipped that. Finally, it seems like chip needs to be explicitly asked to transition into ready status on every command. Failing to do this means that if two commands are sent in succession without an idle/ready transition in between, everything will appear to work fine but the response is simply the original command. I'm working without any docs here, so I'm not sure if this is actually the required behaviour or if I'm missing something somewhere else, but doing this results in the chip working reliably. Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Matthew Garrett <mjg59@srcf.ucam.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-01-12Merge tag 'for-linus-6.2-rc4-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: - two cleanup patches - a fix of a memory leak in the Xen pvfront driver - a fix of a locking issue in the Xen hypervisor console driver * tag 'for-linus-6.2-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/pvcalls: free active map buffer on pvcalls_front_free_map hvc/xen: lock console list traversal x86/xen: Remove the unused function p2m_index() xen: make remove callback of xen driver void returned
2023-01-06tpm: Allow system suspend to continue when TPM suspend failsJason A. Donenfeld
TPM 1 is sometimes broken across system suspends, due to races or locking issues or something else that haven't been diagnosed or fixed yet, most likely having to do with concurrent reads from the TPM's hardware random number generator driver. These issues prevent the system from actually suspending, with errors like: tpm tpm0: A TPM error (28) occurred continue selftest ... tpm tpm0: A TPM error (28) occurred attempting get random ... tpm tpm0: Error (28) sending savestate before suspend tpm_tis 00:08: PM: __pnp_bus_suspend(): tpm_pm_suspend+0x0/0x80 returns 28 tpm_tis 00:08: PM: dpm_run_callback(): pnp_bus_suspend+0x0/0x10 returns 28 tpm_tis 00:08: PM: failed to suspend: error 28 PM: Some devices failed to suspend, or early wake event detected This issue was partially fixed by 23393c646142 ("char: tpm: Protect tpm_pm_suspend with locks"), in a last minute 6.1 commit that Linus took directly because the TPM maintainers weren't available. However, it seems like this just addresses the most common cases of the bug, rather than addressing it entirely. So there are more things to fix still, apparently. In lieu of actually fixing the underlying bug, just allow system suspend to continue, so that laptops still go to sleep fine. Later, this can be reverted when the real bug is fixed. Link: https://lore.kernel.org/lkml/7cbe96cf-e0b5-ba63-d1b4-f63d2e826efa@suse.cz/ Cc: stable@vger.kernel.org # 6.1+ Reported-by: Vlastimil Babka <vbabka@suse.cz> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Luigi Semenzato <semenzato@chromium.org> Cc: Peter Huewe <peterhuewe@gmx.de> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: Johannes Altmanninger <aclopte@gmail.com> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-12-15xen: make remove callback of xen driver void returnedDawei Li
Since commit fc7a6209d571 ("bus: Make remove callback return void") forces bus_type::remove be void-returned, it doesn't make much sense for any bus based driver implementing remove callbalk to return non-void to its caller. This change is for xen bus based drivers. Acked-by: Juergen Gross <jgross@suse.com> Signed-off-by: Dawei Li <set_pte_at@outlook.com> Link: https://lore.kernel.org/r/TYCP286MB23238119AB4DF190997075C9CAE39@TYCP286MB2323.JPNP286.PROD.OUTLOOK.COM Signed-off-by: Juergen Gross <jgross@suse.com>
2022-12-12Merge tag 'acpi-6.2-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI and PNP updates from Rafael Wysocki: "These include new code (for instance, support for the FFH address space type and support for new firmware data structures in ACPICA), some new quirks (mostly related to backlight handling and I2C enumeration), a number of fixes and a fair amount of cleanups all over. Specifics: - Update the ACPICA code in the kernel to the 20221020 upstream version and fix a couple of issues in it: - Make acpi_ex_load_op() match upstream implementation (Rafael Wysocki) - Add support for loong_arch-specific APICs in MADT (Huacai Chen) - Add support for fixed PCIe wake event (Huacai Chen) - Add EBDA pointer sanity checks (Vit Kabele) - Avoid accessing VGA memory when EBDA < 1KiB (Vit Kabele) - Add CCEL table support to both compiler/disassembler (Kuppuswamy Sathyanarayanan) - Add a couple of new UUIDs to the known UUID list (Bob Moore) - Add support for FFH Opregion special context data (Sudeep Holla) - Improve warning message for "invalid ACPI name" (Bob Moore) - Add support for CXL 3.0 structures (CXIMS & RDPAS) in the CEDT table (Alison Schofield) - Prepare IORT support for revision E.e (Robin Murphy) - Finish support for the CDAT table (Bob Moore) - Fix error code path in acpi_ds_call_control_method() (Rafael Wysocki) - Fix use-after-free in acpi_ut_copy_ipackage_to_ipackage() (Li Zetao) - Update the version of the ACPICA code in the kernel (Bob Moore) - Use ZERO_PAGE(0) instead of empty_zero_page in the ACPI device enumeration code (Giulio Benetti) - Change the return type of the ACPI driver remove callback to void and update its users accordingly (Dawei Li) - Add general support for FFH address space type and implement the low- level part of it for ARM64 (Sudeep Holla) - Fix stale comments in the ACPI tables parsing code and make it print more messages related to MADT (Hanjun Guo, Huacai Chen) - Replace invocations of generic library functions with more kernel- specific counterparts in the ACPI sysfs interface (Christophe JAILLET, Xu Panda) - Print full name paths of ACPI power resource objects during enumeration (Kane Chen) - Eliminate a compiler warning regarding a missing function prototype in the ACPI power management code (Sudeep Holla) - Fix and clean up the ACPI processor driver (Rafael Wysocki, Li Zhong, Colin Ian King, Sudeep Holla) - Add quirk for the HP Pavilion Gaming 15-cx0041ur to the ACPI EC driver (Mia Kanashi) - Add some mew ACPI backlight handling quirks and update some existing ones (Hans de Goede) - Make the ACPI backlight driver prefer the native backlight control over vendor backlight control when possible (Hans de Goede) - Drop unsetting ACPI APEI driver data on remove (Uwe Kleine-König) - Use xchg_release() instead of cmpxchg() for updating new GHES cache slots (Ard Biesheuvel) - Clean up the ACPI APEI code (Sudeep Holla, Christophe JAILLET, Jay Lu) - Add new I2C device enumeration quirks for Medion Lifetab S10346 and Lenovo Yoga Tab 3 Pro (YT3-X90F) (Hans de Goede) - Make the ACPI battery driver notify user space about adding new battery hooks and removing the existing ones (Armin Wolf) - Modify the pfr_update and pfr_telemetry drivers to use ACPI_FREE() for freeing acpi_object structures to help diagnostics (Wang ShaoBo) - Make the ACPI fan driver use sysfs_emit_at() in its sysfs interface code (ye xingchen) - Fix the _FIF package extraction failure handling in the ACPI fan driver (Hanjun Guo) - Fix the PCC mailbox handling error code path (Huisong Li) - Avoid using PCC Opregions if there is no platform interrupt allocated for this purpose (Huisong Li) - Use sysfs_emit() instead of scnprintf() in the ACPI PAD driver and CPPC library (ye xingchen) - Fix some kernel-doc issues in the ACPI GSI processing code (Xiongfeng Wang) - Fix name memory leak in pnp_alloc_dev() (Yang Yingliang) - Do not disable PNP devices on suspend when they cannot be re-enabled on resume (Hans de Goede) - Clean up the ACPI thermal driver a bit (Rafael Wysocki)" * tag 'acpi-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (67 commits) ACPI: x86: Add skip i2c clients quirk for Medion Lifetab S10346 ACPI: APEI: EINJ: Refactor available_error_type_show() ACPI: APEI: EINJ: Fix formatting errors ACPI: processor: perflib: Adjust acpi_processor_notify_smm() return value ACPI: processor: perflib: Rearrange acpi_processor_notify_smm() ACPI: processor: perflib: Rearrange unregistration routine ACPI: processor: perflib: Drop redundant parentheses ACPI: processor: perflib: Adjust white space ACPI: processor: idle: Drop unnecessary statements and parens ACPI: thermal: Adjust critical.flags.valid check ACPI: fan: Convert to use sysfs_emit_at() API ACPICA: Fix use-after-free in acpi_ut_copy_ipackage_to_ipackage() ACPI: battery: Call power_supply_changed() when adding hooks ACPI: use sysfs_emit() instead of scnprintf() ACPI: x86: Add skip i2c clients quirk for Lenovo Yoga Tab 3 Pro (YT3-X90F) ACPI: APEI: Remove a useless include PNP: Do not disable devices on suspend when they cannot be re-enabled on resume ACPI: processor: Silence missing prototype warnings ACPI: processor_idle: Silence missing prototype warnings ACPI: PM: Silence missing prototype warning ...
2022-12-12Merge tag 'timers-core-2022-12-10' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer updates from Thomas Gleixner: "Updates for timers, timekeeping and drivers: Core: - The timer_shutdown[_sync]() infrastructure: Tearing down timers can be tedious when there are circular dependencies to other things which need to be torn down. A prime example is timer and workqueue where the timer schedules work and the work arms the timer. What needs to prevented is that pending work which is drained via destroy_workqueue() does not rearm the previously shutdown timer. Nothing in that shutdown sequence relies on the timer being functional. The conclusion was that the semantics of timer_shutdown_sync() should be: - timer is not enqueued - timer callback is not running - timer cannot be rearmed Preventing the rearming of shutdown timers is done by discarding rearm attempts silently. A warning for the case that a rearm attempt of a shutdown timer is detected would not be really helpful because it's entirely unclear how it should be acted upon. The only way to address such a case is to add 'if (in_shutdown)' conditionals all over the place. This is error prone and in most cases of teardown not required all. - The real fix for the bluetooth HCI teardown based on timer_shutdown_sync(). A larger scale conversion to timer_shutdown_sync() is work in progress. - Consolidation of VDSO time namespace helper functions - Small fixes for timer and timerqueue Drivers: - Prevent integer overflow on the XGene-1 TVAL register which causes an never ending interrupt storm. - The usual set of new device tree bindings - Small fixes and improvements all over the place" * tag 'timers-core-2022-12-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits) dt-bindings: timer: renesas,cmt: Add r8a779g0 CMT support dt-bindings: timer: renesas,tmu: Add r8a779g0 support clocksource/drivers/arm_arch_timer: Use kstrtobool() instead of strtobool() clocksource/drivers/timer-ti-dm: Fix missing clk_disable_unprepare in dmtimer_systimer_init_clock() clocksource/drivers/timer-ti-dm: Clear settings on probe and free clocksource/drivers/timer-ti-dm: Make timer_get_irq static clocksource/drivers/timer-ti-dm: Fix warning for omap_timer_match clocksource/drivers/arm_arch_timer: Fix XGene-1 TVAL register math error clocksource/drivers/timer-npcm7xx: Enable timer 1 clock before use dt-bindings: timer: nuvoton,npcm7xx-timer: Allow specifying all clocks dt-bindings: timer: rockchip: Add rockchip,rk3128-timer clockevents: Repair kernel-doc for clockevent_delta2ns() clocksource/drivers/ingenic-ost: Define pm functions properly in platform_driver struct clocksource/drivers/sh_cmt: Access registers according to spec vdso/timens: Refactor copy-pasted find_timens_vvar_page() helper into one copy Bluetooth: hci_qca: Fix the teardown problem for real timers: Update the documentation to reflect on the new timer_shutdown() API timers: Provide timer_shutdown[_sync]() timers: Add shutdown mechanism to the internal functions timers: Split [try_to_]del_timer[_sync]() to prepare for shutdown mode ...
2022-12-12Merge branches 'acpi-scan', 'acpi-bus', 'acpi-tables' and 'acpi-sysfs'Rafael J. Wysocki
Merge ACPI changes related to device enumeration, device object managenet, operation region handling, table parsing and sysfs interface: - Use ZERO_PAGE(0) instead of empty_zero_page in the ACPI device enumeration code (Giulio Benetti). - Change the return type of the ACPI driver remove callback to void and update its users accordingly (Dawei Li). - Add general support for FFH address space type and implement the low- level part of it for ARM64 (Sudeep Holla). - Fix stale comments in the ACPI tables parsing code and make it print more messages related to MADT (Hanjun Guo, Huacai Chen). - Replace invocations of generic library functions with more kernel- specific counterparts in the ACPI sysfs interface (Christophe JAILLET, Xu Panda). * acpi-scan: ACPI: scan: substitute empty_zero_page with helper ZERO_PAGE(0) * acpi-bus: ACPI: FFH: Silence missing prototype warnings ACPI: make remove callback of ACPI driver void ACPI: bus: Fix the _OSC capability check for FFH OpRegion arm64: Add architecture specific ACPI FFH Opregion callbacks ACPI: Implement a generic FFH Opregion handler * acpi-tables: ACPI: tables: Fix the stale comments for acpi_locate_initial_tables() ACPI: tables: Print CORE_PIC information when MADT is parsed * acpi-sysfs: ACPI: sysfs: use sysfs_emit() to instead of scnprintf() ACPI: sysfs: Use kstrtobool() instead of strtobool()
2022-12-08tpm: st33zp24: remove pointless checks on probeDmitry Torokhov
Remove tests for SPI device or I2C client to be non-NULL because driver core will never call driver's probe method without having a valid device structure. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2022-12-08tpm/tpm_crb: Fix error message in __crb_relinquish_locality()Michael Kelley
The error message in __crb_relinquish_locality() mentions requestAccess instead of Relinquish. Fix it. Fixes: 888d867df441 ("tpm: cmd_ready command can be issued only after granting locality") Signed-off-by: Michael Kelley <mikelley@microsoft.com> Acked-by: Tomas Winkler <tomas.winkler@intel.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2022-12-08tpm/tpm_ftpm_tee: Fix error handling in ftpm_mod_init()Yuan Can
The ftpm_mod_init() returns the driver_register() directly without checking its return value, if driver_register() failed, the ftpm_tee_plat_driver is not unregistered. Fix by unregister ftpm_tee_plat_driver when driver_register() failed. Fixes: 9f1944c23c8c ("tpm_ftpm_tee: register driver on TEE bus") Signed-off-by: Yuan Can <yuancan@huawei.com> Reviewed-by: Maxim Uvarov <maxim.uvarov@linaro.org> Acked-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2022-12-08tpm: tpm_tis: Add the missed acpi_put_table() to fix memory leakHanjun Guo
In check_acpi_tpm2(), we get the TPM2 table just to make sure the table is there, not used after the init, so the acpi_put_table() should be added to release the ACPI memory. Fixes: 4cb586a188d4 ("tpm_tis: Consolidate the platform and acpi probe flow") Cc: stable@vger.kernel.org Signed-off-by: Hanjun Guo <guohanjun@huawei.com> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2022-12-08tpm: tpm_crb: Add the missed acpi_put_table() to fix memory leakHanjun Guo
In crb_acpi_add(), we get the TPM2 table to retrieve information like start method, and then assign them to the priv data, so the TPM2 table is not used after the init, should be freed, call acpi_put_table() to fix the memory leak. Fixes: 30fc8d138e91 ("tpm: TPM 2.0 CRB Interface") Cc: stable@vger.kernel.org Signed-off-by: Hanjun Guo <guohanjun@huawei.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2022-12-08tpm: acpi: Call acpi_put_table() to fix memory leakHanjun Guo
The start and length of the event log area are obtained from TPM2 or TCPA table, so we call acpi_get_table() to get the ACPI information, but the acpi_get_table() should be coupled with acpi_put_table() to release the ACPI memory, add the acpi_put_table() properly to fix the memory leak. While we are at it, remove the redundant empty line at the end of the tpm_read_log_acpi(). Fixes: 0bfb23746052 ("tpm: Move eventlog files to a subdirectory") Fixes: 85467f63a05c ("tpm: Add support for event log pointer found in TPM2 ACPI table") Cc: stable@vger.kernel.org Signed-off-by: Hanjun Guo <guohanjun@huawei.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2022-12-08tpm: Add flag to use default cancellation policyEddie James
The check for cancelled request depends on the VID of the chip, but some chips share VID which shouldn't share their cancellation behavior. This is the case for the Nuvoton NPCT75X, which should use the default cancellation check, not the Winbond one. To avoid changing the existing behavior, add a new flag to indicate that the chip should use the default cancellation check and set it for the I2C TPM2 TIS driver. Fixes: bbc23a07b072 ("tpm: Add tpm_tis_i2c backend for tpm_tis_core") Signed-off-by: Eddie James <eajames@linux.ibm.com> Tested-by: Joel Stanley <joel@jms.id.au> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2022-12-08tpm: tis_i2c: Fix sanity check interrupt enable maskEddie James
The sanity check mask for TPM_INT_ENABLE register was off by 8 bits, resulting in failure to probe if the TPM_INT_ENABLE register was a valid value. Fixes: bbc23a07b072 ("tpm: Add tpm_tis_i2c backend for tpm_tis_core") Signed-off-by: Eddie James <eajames@linux.ibm.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Tested-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2022-12-08tpm: Avoid function type cast of put_device()Ard Biesheuvel
The TPM code registers put_device() as a devm cleanup handler, and casts the reference to the right function pointer type for this to be permitted by the compiler. However, under kCFI, this is rejected at runtime, resulting in a splat like CFI failure at devm_action_release+0x24/0x3c (target: put_device+0x0/0x24; expected type: 0xa488ebfc) Internal error: Oops - CFI: 0000000000000000 [#1] PREEMPT SMP Modules linked in: ... CPU: 20 PID: 454 Comm: systemd-udevd Not tainted 6.1.0-rc1+ #51 Hardware name: Socionext SynQuacer E-series DeveloperBox, BIOS build #1 Oct 3 2022 pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : devm_action_release+0x24/0x3c lr : devres_release_all+0xb4/0x114 sp : ffff800009bb3630 x29: ffff800009bb3630 x28: 0000000000000000 x27: 0000000000000011 x26: ffffaa6f9922c0c8 x25: 0000000000000002 x24: 000000000000000f x23: ffff800009bb3648 x22: ffff7aefc3be2100 x21: ffff7aefc3be2e00 x20: 0000000000000005 x19: ffff7aefc1e1ec10 x18: ffff800009af70a8 x17: 00000000a488ebfc x16: 0000000094ee7df3 x15: 0000000000000000 x14: 4075c5c2ef7affff x13: e46a91c5c5e2ef42 x12: ffff7aefc2c57540 x11: 0000000000000001 x10: 0000000000000001 x9 : 0000000100000000 x8 : ffffaa6fa09b39b4 x7 : 7f7f7f7f7f7f7f7f x6 : 8000000000000000 x5 : 000000008020000e x4 : ffff7aefc2c57500 x3 : ffff800009bb3648 x2 : ffff800009bb3648 x1 : ffff7aefc3be2e80 x0 : ffff7aefc3bb7000 Call trace: devm_action_release+0x24/0x3c devres_release_all+0xb4/0x114 really_probe+0xb0/0x49c __driver_probe_device+0x114/0x180 driver_probe_device+0x48/0x1ec __driver_attach+0x118/0x284 bus_for_each_dev+0x94/0xe4 driver_attach+0x24/0x34 bus_add_driver+0x10c/0x220 driver_register+0x78/0x118 __platform_driver_register+0x24/0x34 init_module+0x20/0xfe4 [tpm_tis_synquacer] do_one_initcall+0xd4/0x248 do_init_module+0x44/0x28c load_module+0x16b4/0x1920 Fix this by going through a helper function of the correct type. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2022-12-08tpm: st33zp24: switch to using gpiod APIDmitry Torokhov
Switch the driver from legacy gpio API (that uses flat GPIO numbering) to the newer gpiod API (which used descriptors and respects line polarities specified in ACPI or device tree). Because gpio handling code for SPI and I2C variants duplicates each other it is moved into the core code for the driver. Also, it seems that the driver never assigned tpm_dev->io_lpcpd in the past, so gpio-based power management was most likely not working ever. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2022-12-08tpm: st33zp24: drop support for platform dataDmitry Torokhov
Drop support for platform data from the driver because there are no users of st33zp24_platform_data structure in the mainline kernel. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2022-12-04char: tpm: Protect tpm_pm_suspend with locksJan Dabros
Currently tpm transactions are executed unconditionally in tpm_pm_suspend() function, which may lead to races with other tpm accessors in the system. Specifically, the hw_random tpm driver makes use of tpm_get_random(), and this function is called in a loop from a kthread, which means it's not frozen alongside userspace, and so can race with the work done during system suspend: tpm tpm0: tpm_transmit: tpm_recv: error -52 tpm tpm0: invalid TPM_STS.x 0xff, dumping stack for forensics CPU: 0 PID: 1 Comm: init Not tainted 6.1.0-rc5+ #135 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.0-20220807_005459-localhost 04/01/2014 Call Trace: tpm_tis_status.cold+0x19/0x20 tpm_transmit+0x13b/0x390 tpm_transmit_cmd+0x20/0x80 tpm1_pm_suspend+0xa6/0x110 tpm_pm_suspend+0x53/0x80 __pnp_bus_suspend+0x35/0xe0 __device_suspend+0x10f/0x350 Fix this by calling tpm_try_get_ops(), which itself is a wrapper around tpm_chip_start(), but takes the appropriate mutex. Signed-off-by: Jan Dabros <jsd@semihalf.com> Reported-by: Vlastimil Babka <vbabka@suse.cz> Tested-by: Jason A. Donenfeld <Jason@zx2c4.com> Tested-by: Vlastimil Babka <vbabka@suse.cz> Link: https://lore.kernel.org/all/c5ba47ef-393f-1fba-30bd-1230d1b4b592@suse.cz/ Cc: stable@vger.kernel.org Fixes: e891db1a18bf ("tpm: turn on TPM on suspend for TPM 1.x") [Jason: reworked commit message, added metadata] Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-11-24timers: Get rid of del_singleshot_timer_sync()Thomas Gleixner
del_singleshot_timer_sync() used to be an optimization for deleting timers which are not rearmed from the timer callback function. This optimization turned out to be broken and got mapped to del_timer_sync() about 17 years ago. Get rid of the undocumented indirection and use del_timer_sync() directly. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Guenter Roeck <linux@roeck-us.net> Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> Reviewed-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Link: https://lore.kernel.org/r/20221123201624.706987932@linutronix.de