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* spi: pxa2xx: Remove DMA parameters from struct chip_dataAndy Shevchenko2024-05-033-61/+9
| | | | | | | | | | | The DMA related fields are set once and never modified. It effectively repeats the content of the same fields in struct pxa2xx_spi_controller. With that, remove DMA parameters from struct chip_data. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20240417110334.2671228-8-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
* spi: pxa2xx: Drop struct pxa2xx_spi_chipAndy Shevchenko2024-05-033-46/+2
| | | | | | | | | No more users. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20240417110334.2671228-7-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
* spi: pxa2xx: Don't use "proxy" headersAndy Shevchenko2024-05-034-7/+22
| | | | | | | | | | Update header inclusions to follow IWYU (Include What You Use) principle. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20240417110334.2671228-6-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
* spi: pxa2xx: Remove outdated documentationAndy Shevchenko2024-05-032-210/+1
| | | | | | | | | | | | The documentation is referring to the legacy enumeration of the SPI host controllers and target devices. It has nothing to do with the modern way, which is the only supported in kernel right now. Hence, remove outdated documentation file. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20240417110334.2671228-5-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
* spi: pxa2xx: Move contents of linux/spi/pxa2xx_spi.h to a local oneAndy Shevchenko2024-05-035-53/+37
| | | | | | | | | | | There is no user of the linux/spi/pxa2xx_spi.h. Move its contents to the drivers/spi/spi-pxa2xx.h. Suggested-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20240417110334.2671228-4-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
* spi: pxa2xx: Provide num-cs for Sharp PDAs via device propertiesAndy Shevchenko2024-05-031-7/+18
| | | | | | | | | | | | | | | | | | | Since driver can parse num-cs device property, replace platform data with this new approach. This pursues the following objectives: - getting rid of the public header that barely used outside of the SPI subsystem (more specifically the SPI PXA2xx drivers) - making a trampoline for the driver to support non-default number of the chip select pins in case the original code is going to be converted to Device Tree model It's not expected to have more users in board files except this one. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20240417110334.2671228-3-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
* spi: pxa2xx: Allow number of chip select pins to be read from propertyAndy Shevchenko2024-05-031-1/+5
| | | | | | | | | | In some cases the number of the chip select pins might come from the device property. Allow driver to use it. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20240417110334.2671228-2-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
* spi: use 'time_left' instead of 'timeout' withMark Brown2024-05-018-43/+45
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge series from Wolfram Sang <wsa+renesas@sang-engineering.com>: There is a confusing pattern in the kernel to use a variable named 'timeout' to store the result of wait_for_*() functions 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 obvious and self explaining. This is part of a tree-wide series. The rest of the patches can be found here (some parts may still be WIP): git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux.git i2c/time_left Because these patches are generated, I audit them before sending. This is why I will send series step by step. Build bot is happy with these patches, though. No functional changes intended.
| * spi: xlp: use 'time_left' variable with wait_for_completion_timeout()Wolfram Sang2024-04-301-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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. Fix to the proper variable type 'unsigned long' while here. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Link: https://lore.kernel.org/r/20240430114142.28551-9-wsa+renesas@sang-engineering.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: sun6i: use 'time_left' variable with wait_for_completion_timeout()Wolfram Sang2024-04-301-8/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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. Fix to the proper variable type 'unsigned long' while here. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com> Reviewed-by: Andre Przywara <andre.przywara@arm.com> Link: https://lore.kernel.org/r/20240430114142.28551-8-wsa+renesas@sang-engineering.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: sun4i: use 'time_left' variable with wait_for_completion_timeout()Wolfram Sang2024-04-301-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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. Fix to the proper variable type 'unsigned long' while here. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com> Reviewed-by: Andre Przywara <andre.przywara@arm.com> Link: https://lore.kernel.org/r/20240430114142.28551-7-wsa+renesas@sang-engineering.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: pic32: use 'time_left' variable with wait_for_completion_timeout()Wolfram Sang2024-04-301-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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> Link: https://lore.kernel.org/r/20240430114142.28551-6-wsa+renesas@sang-engineering.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: pic32-sqi: use 'time_left' variable with wait_for_completion_timeout()Wolfram Sang2024-04-301-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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> Link: https://lore.kernel.org/r/20240430114142.28551-5-wsa+renesas@sang-engineering.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: imx: use 'time_left' variable with wait_for_completion_timeout()Wolfram Sang2024-04-301-10/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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> Reviewed-by: Peng Fan <peng.fan@nxp.com> Link: https://lore.kernel.org/r/20240430114142.28551-4-wsa+renesas@sang-engineering.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: fsl-lpspi: use 'time_left' variable with wait_for_completion_timeout()Wolfram Sang2024-04-301-7/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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> Link: https://lore.kernel.org/r/20240430114142.28551-3-wsa+renesas@sang-engineering.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: armada-3700: use 'time_left' variable with wait_for_completion_timeout()Wolfram Sang2024-04-301-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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. Fix to the proper variable type 'unsigned long' while here. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Link: https://lore.kernel.org/r/20240430114142.28551-2-wsa+renesas@sang-engineering.com Signed-off-by: Mark Brown <broonie@kernel.org>
* | Add add SPI-NAND Flash controller driver for EN7581Mark Brown2024-05-015-0/+1214
|\ \ | | | | | | | | | | | | | | | | | | Merge series from Lorenzo Bianconi <lorenzo@kernel.org>: Introduce support for SPI-NAND driver of the Airoha NAND Flash Interface found on Airoha ARM EN7581 SoCs.
| * | spi: dt-bindings: airoha: Add YAML schema for SNFI controllerLorenzo Bianconi2024-04-301-0/+65
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce Airoha EN7581 SPI NAND controller binding Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Tested-by: Rajeev Kumar <Rajeev.Kumar@airoha.com> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Link: https://lore.kernel.org/r/f3377b323f00589e6b7ed7950c4840d18129238b.1714377864.git.lorenzo@kernel.org Signed-off-by: Mark Brown <broonie@kernel.org>
| * | spi: airoha: add SPI-NAND Flash controller driverLorenzo Bianconi2024-04-304-0/+1149
| |/ | | | | | | | | | | | | | | | | | | | | | | Introduce support for SPI-NAND driver of the Airoha NAND Flash Interface found on Airoha ARM SoCs. Tested-by: Rajeev Kumar <Rajeev.Kumar@airoha.com> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Reviewed-by: Andy Shevchenko <andy@kernel.org> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Link: https://lore.kernel.org/r/6c9db20505b01a66807995374f2af475a23ce5b2.1714377864.git.lorenzo@kernel.org Signed-off-by: Mark Brown <broonie@kernel.org>
* / spi: use spi_valid_{tx,rx}buf() in stats functionDavid Lechner2024-05-011-7/+5
|/ | | | | | | | | | | | | | | | | | There are macros spi_valid_txbuf() and spi_valid_rxbuf() for determining if an xfer actually intended to send or receive data. These checks were hard-coded in spi_statistics_add_transfer_stats(). We can make use of the macros instead to make the code more readable and more robust against potential future changes in case the definition of what valid means changes. The macro takes the spi_message as an argument, so we need to change spi_statistics_add_transfer_stats() to take the spi_message as an argument instead of the controller. Signed-off-by: David Lechner <dlechner@baylibre.com> Link: https://lore.kernel.org/r/20240430201530.2138095-3-dlechner@baylibre.com Signed-off-by: Mark Brown <broonie@kernel.org>
* spi: cadence-qspi: add mobileye,eyeq5-ospi compatibleThéo Lebrun2024-04-261-0/+10
| | | | | | | | Declare a new mobileye,eyeq5-ospi compatible. Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> Link: https://lore.kernel.org/r/20240423-cdns-qspi-mbly-v4-4-3d2a7b535ad0@bootlin.com Signed-off-by: Mark Brown <broonie@kernel.org>
* spi: cadence-qspi: add early busywait to cqspi_wait_for_bit()Théo Lebrun2024-04-261-8/+23
| | | | | | | | | | | | | Call readl_relaxed_poll_timeout() with no sleep at the start of cqspi_wait_for_bit(). If its short timeout expires, a sleeping readl_relaxed_poll_timeout() call takes the relay. The reason is to avoid hrtimer interrupts on the system. All read operations are expected to take less than 100µs. Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> Link: https://lore.kernel.org/r/20240423-cdns-qspi-mbly-v4-3-3d2a7b535ad0@bootlin.com Signed-off-by: Mark Brown <broonie@kernel.org>
* spi: cadence-qspi: add no-IRQ mode to indirect readsThéo Lebrun2024-04-261-4/+9
| | | | | | | | | | | | | | | | | | | | Support reads through polling, without any IRQ. The main reason is performance; profiling shows that the first IRQ comes quickly on our specific hardware. Once this IRQ arrives, we poll until all data is retrieved. Avoid initial sleep to reduce IRQ count. Hide this behavior behind a quirk flag. This is confirmed through micro-benchmarks, but also end-to-end performance tests. Mobileye EyeQ5, octal flash, reading 235M on a UBIFS filesystem: - No optimizations, ~10.34s, ~22.7 MB/s, 199230 IRQs - CQSPI_SLOW_SRAM, ~10.34s, ~22.7 MB/s, 70284 IRQs - CQSPI_RD_NO_IRQ, ~9.37s, ~25.1 MB/s, 521 IRQs Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> Link: https://lore.kernel.org/r/20240423-cdns-qspi-mbly-v4-2-3d2a7b535ad0@bootlin.com Signed-off-by: Mark Brown <broonie@kernel.org>
* spi: cadence-qspi: allow FIFO depth detectionThéo Lebrun2024-04-261-7/+30
| | | | | | | | | | | | | | If FIFO depth DT property is provided, check it matches what hardware reports and warn otherwise. Else, use hardware provided value. Hardware exposes FIFO depth indirectly because CQSPI_REG_SRAMPARTITION is partially read-only. Move probe cqspi->ddata assignment prior to cqspi_of_get_pdata() call. Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> Link: https://lore.kernel.org/r/20240423-cdns-qspi-mbly-v4-1-3d2a7b535ad0@bootlin.com Signed-off-by: Mark Brown <broonie@kernel.org>
* spi: spi-s3c64xx.c: Remove of_node_put for auto cleanupShivani Gupta2024-04-241-3/+3
| | | | | | | | | | | | | | Use the scope based of_node_put() cleanup in s3c64xx_spi_csinfo to automatically release the device node with the __free() cleanup handler Initialize data_np at the point of declaration for clarity of scope. This change reduces the risk of memory leaks and simplifies the code by removing manual node put call. Suggested-by: Julia Lawall <julia.lawall@inria.fr> Signed-off-by: Shivani Gupta <shivani07g@gmail.com> Link: https://lore.kernel.org/r/20240418000505.731724-1-shivani07g@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org>
* spi: mux: Fix master controller settings after mux selectHeikki Keranen2024-04-231-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | In some cases SPI child devices behind spi-mux require different settings like: max_speed_hz, mode and bits_per_word. Typically the slave device driver puts the settings in place and calls spi_setup() once during probe and assumes they stay in place for all following spi transfers. However spi-mux forwarded spi_setup() -call to SPI master driver only when slave driver calls spi_setup(). If second slave device was accessed meanwhile and that driver called spi_setup(), the settings did not change back to the first spi device. In case of wrong max_speed_hz this caused spi trasfers to fail. This commit adds spi_setup() call after mux is changed. This way the right device specific parameters are set to the master driver. The fix has been tested by using custom hardware and debugging spi master driver speed settings. Co-authored-by: Petri Tauriainen <petri.tauriainen@bittium.com> Signed-off-by: Heikki Keranen <heikki.keranen@bittium.com> Link: https://lore.kernel.org/r/20240422114150.84426-1-heikki.keranen@bittium.com Signed-off-by: Mark Brown <broonie@kernel.org>
* spi: dt-bindings: armada-3700: convert to dtschemaKousik Sanagavarapu2024-04-212-25/+55
| | | | | | | | | | Convert txt binding of marvell armada 3700 SoC spi controller to dtschema to allow for validation. Signed-off-by: Kousik Sanagavarapu <five231003@gmail.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20240417052729.6612-1-five231003@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org>
* spi: cs42l43: Correct name of ACPI propertyMaciej Strozek2024-04-191-1/+1
| | | | | | | | | Fixes: 439fbc97502a ("spi: cs42l43: Add bridged cs35l56 amplifiers") Signed-off-by: Maciej Strozek <mstrozek@opensource.cirrus.com> Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com> Link: https://lore.kernel.org/r/20240418103315.1487267-1-mstrozek@opensource.cirrus.com Signed-off-by: Mark Brown <broonie@kernel.org>
* spi: oc-tiny: Remove unused of_gpio.hAndy Shevchenko2024-04-171-2/+0
| | | | | | | | | of_gpio.h is deprecated and subject to remove. The driver doesn't use it, simply remove the unused header. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20240417104730.2510856-1-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
* spi: cs42l43: Use devm_add_action_or_reset()Charles Keepax2024-04-171-8/+4
| | | | | | | | | | | Use devm_add_action_or_reset() rather than manually cleaning up on the error path. Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Link: https://lore.kernel.org/r/20240417093026.79396-1-ckeepax@opensource.cirrus.com Signed-off-by: Mark Brown <broonie@kernel.org>
* spi: renesas,sh-msiof: Add r8a779h0 supportGeert Uytterhoeven2024-04-171-0/+1
| | | | | | | | | | Document support for the Clock-Synchronized Serial Interface with FIFO (MSIOF) in the Renesas R-Car V4M (R8A779H0) SoC. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/68a4d8ad8638c1133e21d0eef87e8982ddea3dd8.1713279687.git.geert+renesas@glider.be Signed-off-by: Mark Brown <broonie@kernel.org>
* Add bridged amplifiers to cs42l43Mark Brown2024-04-17833-4843/+10722
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge series from Charles Keepax <ckeepax@opensource.cirrus.com>: In some cs42l43 systems a couple of cs35l56 amplifiers are attached to the cs42l43's SPI and I2S. On Windows the cs42l43 is controlled by a SDCA class driver and these two amplifiers are controlled by firmware running on the cs42l43. However, under Linux the decision was made to interact with the cs42l43 directly, affording the user greater control over the audio system. However, this has resulted in an issue where these two bridged cs35l56 amplifiers are not populated in ACPI and must be added manually. There is at least an SDCA extension unit DT entry we can key off. The process of adding this is handled using a software node, firstly the ability to add native chip selects to software nodes must be added. Secondly, an additional flag for naming the SPI devices is added this allows the machine driver to key to the correct amplifier. Then finally, the cs42l43 SPI driver adds the two amplifiers directly onto its SPI bus. An additional series will follow soon to add the audio machine driver parts (in the sof-sdw driver), however that is fairly orthogonal to this part of the process, getting the actual amplifiers registered.
| * spi: cs42l43: Add bridged cs35l56 amplifiersMaciej Strozek2024-04-162-4/+120
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On some cs42l43 systems a couple of cs35l56 amplifiers are attached to the cs42l43's SPI and I2S. On Windows the cs42l43 is controlled by a SDCA class driver and these two amplifiers are controlled by firmware running on the cs42l43. However, under Linux the decision was made to interact with the cs42l43 directly, affording the user greater control over the audio system. However, this has resulted in an issue where these two bridged cs35l56 amplifiers are not populated in ACPI and must be added manually. Check for the presence of the "01fa-cirrus-sidecar-instances" property in the SDCA extension unit's ACPI properties to confirm the presence of these two amplifiers and if they exist add them manually onto the SPI bus. Reviewed-by: Andy Shevchenko <andy@kernel.org> Signed-off-by: Maciej Strozek <mstrozek@opensource.cirrus.com> Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com> Link: https://lore.kernel.org/r/20240416100904.3738093-5-ckeepax@opensource.cirrus.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: Update swnode based SPI devices to use the fwnode nameCharles Keepax2024-04-161-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | Update the name for software node based SPI devices to use the fwnode name as the device name. This is helpful since swnode devices are usually added within the kernel, and the kernel often then requires a predictable name such that it can refer back to the device. Reviewed-by: Andy Shevchenko <andy@kernel.org> Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com> Link: https://lore.kernel.org/r/20240416100904.3738093-4-ckeepax@opensource.cirrus.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * spi: Switch to using is_acpi_device_node() in spi_dev_set_name()Charles Keepax2024-04-161-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | Use is_acpi_device_node() rather than checking ACPI_COMPANION(), such that when checking for other types of firmware node, the code can consistently do checks against the fwnode. Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com> Link: https://lore.kernel.org/r/20240416100904.3738093-3-ckeepax@opensource.cirrus.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * gpio: swnode: Add ability to specify native chip selects for SPICharles Keepax2024-04-163-0/+57
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | SPI devices can specify a cs-gpios property to enumerate their chip selects. Under device tree, a zero entry in this property can be used to specify that a particular chip select is using the SPI controllers native chip select, for example: cs-gpios = <&gpio1 0 0>, <0>; Here, the second chip select is native. However, when using swnodes there is currently no way to specify a native chip select. The proposal here is to register a swnode_gpio_undefined software node, that can be specified to allow the indication of a native chip select. For example: static const struct software_node_ref_args device_cs_refs[] = { { .node = &device_gpiochip_swnode, .nargs = 2, .args = { 0, GPIO_ACTIVE_LOW }, }, { .node = &swnode_gpio_undefined, .nargs = 0, }, }; Register the swnode as the gpiolib is initialised and check in swnode_get_gpio_device() if the returned node matches swnode_gpio_undefined and return -ENOENT, which matches the behaviour of the device tree system when it encounters a 0 phandle. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Andy Shevchenko <andy@kernel.org> Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com> Link: https://lore.kernel.org/r/20240416100904.3738093-2-ckeepax@opensource.cirrus.com Signed-off-by: Mark Brown <broonie@kernel.org>
| * Linux 6.9-rc3v6.9-rc3Linus Torvalds2024-04-071-1/+1
| |
| * Merge tag 'x86-urgent-2024-04-07' of ↵Linus Torvalds2024-04-0717-41/+166
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: - Fix MCE timer reinit locking - Fix/improve CoCo guest random entropy pool init - Fix SEV-SNP late disable bugs - Fix false positive objtool build warning - Fix header dependency bug - Fix resctrl CPU offlining bug * tag 'x86-urgent-2024-04-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/retpoline: Add NOENDBR annotation to the SRSO dummy return thunk x86/mce: Make sure to grab mce_sysfs_mutex in set_bank() x86/CPU/AMD: Track SNP host status with cc_platform_*() x86/cc: Add cc_platform_set/_clear() helpers x86/kvm/Kconfig: Have KVM_AMD_SEV select ARCH_HAS_CC_PLATFORM x86/coco: Require seeding RNG with RDRAND on CoCo systems x86/numa/32: Include missing <asm/pgtable_areas.h> x86/resctrl: Fix uninitialized memory read when last CPU of domain goes offline
| | * x86/retpoline: Add NOENDBR annotation to the SRSO dummy return thunkBorislav Petkov (AMD)2024-04-061-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | srso_alias_untrain_ret() is special code, even if it is a dummy which is called in the !SRSO case, so annotate it like its real counterpart, to address the following objtool splat: vmlinux.o: warning: objtool: .export_symbol+0x2b290: data relocation to !ENDBR: srso_alias_untrain_ret+0x0 Fixes: 4535e1a4174c ("x86/bugs: Fix the SRSO mitigation on Zen3/4") Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20240405144637.17908-1-bp@kernel.org
| | * Merge branch 'linus' into x86/urgent, to pick up dependent commitIngo Molnar2024-04-06397-2689/+6406
| | |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We want to fix: 0e110732473e ("x86/retpoline: Do the necessary fixup to the Zen3/4 srso return thunk for !SRSO") So merge in Linus's latest into x86/urgent to have it available. Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | x86/mce: Make sure to grab mce_sysfs_mutex in set_bank()Borislav Petkov (AMD)2024-04-041-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Modifying a MCA bank's MCA_CTL bits which control which error types to be reported is done over /sys/devices/system/machinecheck/ ├── machinecheck0 │   ├── bank0 │   ├── bank1 │   ├── bank10 │   ├── bank11 ... sysfs nodes by writing the new bit mask of events to enable. When the write is accepted, the kernel deletes all current timers and reinits all banks. Doing that in parallel can lead to initializing a timer which is already armed and in the timer wheel, i.e., in use already: ODEBUG: init active (active state 0) object: ffff888063a28000 object type: timer_list hint: mce_timer_fn+0x0/0x240 arch/x86/kernel/cpu/mce/core.c:2642 WARNING: CPU: 0 PID: 8120 at lib/debugobjects.c:514 debug_print_object+0x1a0/0x2a0 lib/debugobjects.c:514 Fix that by grabbing the sysfs mutex as the rest of the MCA sysfs code does. Reported by: Yue Sun <samsun1006219@gmail.com> Reported by: xingwei lee <xrivendell7@gmail.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: <stable@kernel.org> Link: https://lore.kernel.org/r/CAEkJfYNiENwQY8yV1LYJ9LjJs%2Bx_-PqMv98gKig55=2vbzffRw@mail.gmail.com
| | * | x86/CPU/AMD: Track SNP host status with cc_platform_*()Borislav Petkov (AMD)2024-04-048-39/+49
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The host SNP worthiness can determined later, after alternatives have been patched, in snp_rmptable_init() depending on cmdline options like iommu=pt which is incompatible with SNP, for example. Which means that one cannot use X86_FEATURE_SEV_SNP and will need to have a special flag for that control. Use that newly added CC_ATTR_HOST_SEV_SNP in the appropriate places. Move kdump_sev_callback() to its rightful place, while at it. Fixes: 216d106c7ff7 ("x86/sev: Add SEV-SNP host initialization support") Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Srikanth Aithal <sraithal@amd.com> Link: https://lore.kernel.org/r/20240327154317.29909-6-bp@alien8.de
| | * | x86/cc: Add cc_platform_set/_clear() helpersBorislav Petkov (AMD)2024-04-042-0/+64
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add functionality to set and/or clear different attributes of the machine as a confidential computing platform. Add the first one too: whether the machine is running as a host for SEV-SNP guests. Fixes: 216d106c7ff7 ("x86/sev: Add SEV-SNP host initialization support") Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Srikanth Aithal <sraithal@amd.com> Link: https://lore.kernel.org/r/20240327154317.29909-5-bp@alien8.de
| | * | x86/kvm/Kconfig: Have KVM_AMD_SEV select ARCH_HAS_CC_PLATFORMBorislav Petkov (AMD)2024-04-041-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The functionality to load SEV-SNP guests by the host will soon rely on cc_platform* helpers because the cpu_feature* API with the early patching is insufficient when SNP support needs to be disabled late. Therefore, pull that functionality in. Fixes: 216d106c7ff7 ("x86/sev: Add SEV-SNP host initialization support") Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Srikanth Aithal <sraithal@amd.com> Link: https://lore.kernel.org/r/20240327154317.29909-4-bp@alien8.de
| | * | x86/coco: Require seeding RNG with RDRAND on CoCo systemsJason A. Donenfeld2024-04-043-0/+45
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are few uses of CoCo that don't rely on working cryptography and hence a working RNG. Unfortunately, the CoCo threat model means that the VM host cannot be trusted and may actively work against guests to extract secrets or manipulate computation. Since a malicious host can modify or observe nearly all inputs to guests, the only remaining source of entropy for CoCo guests is RDRAND. If RDRAND is broken -- due to CPU hardware fault -- the RNG as a whole is meant to gracefully continue on gathering entropy from other sources, but since there aren't other sources on CoCo, this is catastrophic. This is mostly a concern at boot time when initially seeding the RNG, as after that the consequences of a broken RDRAND are much more theoretical. So, try at boot to seed the RNG using 256 bits of RDRAND output. If this fails, panic(). This will also trigger if the system is booted without RDRAND, as RDRAND is essential for a safe CoCo boot. Add this deliberately to be "just a CoCo x86 driver feature" and not part of the RNG itself. Many device drivers and platforms have some desire to contribute something to the RNG, and add_device_randomness() is specifically meant for this purpose. Any driver can call it with seed data of any quality, or even garbage quality, and it can only possibly make the quality of the RNG better or have no effect, but can never make it worse. Rather than trying to build something into the core of the RNG, consider the particular CoCo issue just a CoCo issue, and therefore separate it all out into driver (well, arch/platform) code. [ bp: Massage commit message. ] Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Elena Reshetova <elena.reshetova@intel.com> Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240326160735.73531-1-Jason@zx2c4.com
| | * | x86/numa/32: Include missing <asm/pgtable_areas.h>Arnd Bergmann2024-04-041-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The __vmalloc_start_set declaration is in a header that is not included in numa_32.c in current linux-next: arch/x86/mm/numa_32.c: In function 'initmem_init': arch/x86/mm/numa_32.c:57:9: error: '__vmalloc_start_set' undeclared (first use in this function) 57 | __vmalloc_start_set = true; | ^~~~~~~~~~~~~~~~~~~ arch/x86/mm/numa_32.c:57:9: note: each undeclared identifier is reported only once for each function it appears in Add an explicit #include. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20240403202344.3463169-1-arnd@kernel.org
| | * | x86/resctrl: Fix uninitialized memory read when last CPU of domain goes offlineReinette Chatre2024-04-031-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Tony encountered this OOPS when the last CPU of a domain goes offline while running a kernel built with CONFIG_NO_HZ_FULL: BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 Oops: 0000 [#1] PREEMPT SMP NOPTI ... RIP: 0010:__find_nth_andnot_bit+0x66/0x110 ... Call Trace: <TASK> ? __die() ? page_fault_oops() ? exc_page_fault() ? asm_exc_page_fault() cpumask_any_housekeeping() mbm_setup_overflow_handler() resctrl_offline_cpu() resctrl_arch_offline_cpu() cpuhp_invoke_callback() cpuhp_thread_fun() smpboot_thread_fn() kthread() ret_from_fork() ret_from_fork_asm() </TASK> The NULL pointer dereference is encountered while searching for another online CPU in the domain (of which there are none) that can be used to run the MBM overflow handler. Because the kernel is configured with CONFIG_NO_HZ_FULL the search for another CPU (in its effort to prefer those CPUs that aren't marked nohz_full) consults the mask representing the nohz_full CPUs, tick_nohz_full_mask. On a kernel with CONFIG_CPUMASK_OFFSTACK=y tick_nohz_full_mask is not allocated unless the kernel is booted with the "nohz_full=" parameter and because of that any access to tick_nohz_full_mask needs to be guarded with tick_nohz_full_enabled(). Replace the IS_ENABLED(CONFIG_NO_HZ_FULL) with tick_nohz_full_enabled(). The latter ensures tick_nohz_full_mask can be accessed safely and can be used whether kernel is built with CONFIG_NO_HZ_FULL enabled or not. [ Use Ingo's suggestion that combines the two NO_HZ checks into one. ] Fixes: a4846aaf3945 ("x86/resctrl: Add cpumask_any_housekeeping() for limbo/overflow") Reported-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Babu Moger <babu.moger@amd.com> Link: https://lore.kernel.org/r/ff8dfc8d3dcb04b236d523d1e0de13d2ef585223.1711993956.git.reinette.chatre@intel.com Closes: https://lore.kernel.org/lkml/ZgIFT5gZgIQ9A9G7@agluck-desk3/
| * | | Merge tag 'timers-urgent-2024-04-07' of ↵Linus Torvalds2024-04-079-36/+121
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Ingo Molnar: "Fix various timer bugs: - Fix a timer migration bug that may result in missed events - Fix timer migration group hierarchy event updates - Fix a PowerPC64 build warning - Fix a handful of DocBook annotation bugs" * tag 'timers-urgent-2024-04-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: timers/migration: Return early on deactivation timers/migration: Fix ignored event due to missing CPU update vdso: Use CONFIG_PAGE_SHIFT in vdso/datapage.h timers: Fix text inconsistencies and spelling tick/sched: Fix struct tick_sched doc warnings tick/sched: Fix various kernel-doc warnings timers: Fix kernel-doc format and add Return values time/timekeeping: Fix kernel-doc warnings and typos time/timecounter: Fix inline documentation
| | * | | timers/migration: Return early on deactivationAnna-Maria Behnsen2024-04-051-0/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 4b6f4c5a67c0 ("timer/migration: Remove buggy early return on deactivation") removed the logic to return early in tmigr_update_events() on deactivation. With this the problem with a not properly updated first global event in a hierarchy containing only a single group was fixed. But when having a look at this code path with a hierarchy with more than a single level, now unnecessary work is done (example is partially copied from the message of the commit mentioned above): [GRP1:0] migrator = GRP0:0 active = GRP0:0 nextevt = T0:0i, T0:1 / \ [GRP0:0] [GRP0:1] migrator = 0 migrator = NONE active = 0 active = NONE nextevt = T0i, T1 nextevt = T2 / \ / \ 0 (T0i) 1 (T1) 2 (T2) 3 active idle idle idle 0) CPU 0 is active thus its event is ignored (the letter 'i') and so are upper levels' events. CPU 1 is idle and has the timer T1 enqueued. CPU 2 also has a timer. The expiry order is T0 (ignored) < T1 < T2 [GRP1:0] migrator = GRP0:0 active = GRP0:0 nextevt = T0:0i, T0:1 / \ [GRP0:0] [GRP0:1] migrator = NONE migrator = NONE active = NONE active = NONE nextevt = T1 nextevt = T2 / \ / \ 0 (T0i) 1 (T1) 2 (T2) 3 idle idle idle idle 1) CPU 0 goes idle without global event queued. Therefore KTIME_MAX is pushed as its next expiry and its own event kept as "ignore". Without this early return the following steps happen in tmigr_update_events() when child = null and group = GRP0:0 : lock(GRP0:0->lock); timerqueue_del(GRP0:0, T0i); unlock(GRP0:0->lock); [GRP1:0] migrator = NONE active = NONE nextevt = T0:0, T0:1 / \ [GRP0:0] [GRP0:1] migrator = NONE migrator = NONE active = NONE active = NONE nextevt = T1 nextevt = T2 / \ / \ 0 (T0i) 1 (T1) 2 (T2) 3 idle idle idle idle 2) The change now propagates up to the top. Then tmigr_update_events() updates the group event of GRP0:0 and executes the following steps (child = GRP0:0 and group = GRP0:0): lock(GRP0:0->lock); lock(GRP1:0->lock); evt = tmigr_next_groupevt(GRP0:0); -> this removes the ignored events in GRP0:0 ... update GRP1:0 group event and timerqueue ... unlock(GRP1:0->lock); unlock(GRP0:0->lock); So the dance in 1) with locking the GRP0:0->lock and removing the T0i from the timerqueue is redundand as this is done nevertheless in 2) when tmigr_next_groupevt(GRP0:0) is executed. Revert commit 4b6f4c5a67c0 ("timer/migration: Remove buggy early return on deactivation") and add a condition into return path to skip the return only, when hierarchy contains a single group. Adapt comments accordingly. Fixes: 4b6f4c5a67c0 ("timer/migration: Remove buggy early return on deactivation") Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/87cyr49on2.fsf@somnus
| | * | | timers/migration: Fix ignored event due to missing CPU updateFrederic Weisbecker2024-04-051-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a group event is updated with its expiry unchanged but a different CPU, that target change may go unnoticed and the event may be propagated up with a stale CPU value. The following depicts a scenario that has been actually observed: [GRP2:0] migrator = GRP1:1 active = GRP1:1 nextevt = TGRP1:0 (T0) / \ [GRP1:0] [GRP1:1] migrator = NONE [...] active = NONE nextevt = TGRP0:0 (T0) / \ [GRP0:0] [...] migrator = NONE active = NONE nextevt = T0 / \ 0 (T0) 1 (T1) idle idle 0) The hierarchy has 3 levels. The left part (GRP1:0) is all idle, including CPU 0 and CPU 1 which have a timer each: T0 and T1. They have the same expiry value. [GRP2:0] migrator = GRP1:1 active = GRP1:1 nextevt = KTIME_MAX / \ [GRP1:0] [GRP1:1] migrator = NONE [...] active = NONE nextevt = TGRP0:0 (T0) / \ [GRP0:0] [...] migrator = NONE active = NONE nextevt = T0 / \ 0 (T0) 1 (T1) idle idle 1) The migrator in GRP1:1 handles remotely T0. The event is dequeued from the top and T0 executed. [GRP2:0] migrator = GRP1:1 active = GRP1:1 nextevt = KTIME_MAX / \ [GRP1:0] [GRP1:1] migrator = NONE [...] active = NONE nextevt = TGRP0:0 (T0) / \ [GRP0:0] [...] migrator = NONE active = NONE nextevt = T1 / \ 0 1 (T1) idle idle 2) The migrator in GRP1:1 fetches the next timer for CPU 0 and finds none. But it updates the events from its groups, starting with GRP0:0 which now has T1 as its next event. So far so good. [GRP2:0] migrator = GRP1:1 active = GRP1:1 nextevt = KTIME_MAX / \ [GRP1:0] [GRP1:1] migrator = NONE [...] active = NONE nextevt = TGRP0:0 (T0) / \ [GRP0:0] [...] migrator = NONE active = NONE nextevt = T1 / \ 0 1 (T1) idle idle 3) The migrator in GRP1:1 proceeds upward and updates the events in GRP1:0. The child event TGRP0:0 is found queued with the same expiry as before. And therefore it is left unchanged. However the target CPU is not the same but that fact is ignored so TGRP0:0 still points to CPU 0 when it should point to CPU 1. [GRP2:0] migrator = GRP1:1 active = GRP1:1 nextevt = TGRP1:0 (T0) / \ [GRP1:0] [GRP1:1] migrator = NONE [...] active = NONE nextevt = TGRP0:0 (T0) / \ [GRP0:0] [...] migrator = NONE active = NONE nextevt = T1 / \ 0 1 (T1) idle idle 4) The propagation has reached the top level and TGRP1:0, having TGRP0:0 as its first event, also wrongly points to CPU 0. TGRP1:0 is added to the top level group. [GRP2:0] migrator = GRP1:1 active = GRP1:1 nextevt = KTIME_MAX / \ [GRP1:0] [GRP1:1] migrator = NONE [...] active = NONE nextevt = TGRP0:0 (T0) / \ [GRP0:0] [...] migrator = NONE active = NONE nextevt = T1 / \ 0 1 (T1) idle idle 5) The migrator in GRP1:1 dequeues the next event in top level pointing to CPU 0. But since it actually doesn't see any real event in CPU 0, it early returns. 6) T1 is left unhandled until either CPU 0 or CPU 1 wake up. Some other bad scenario may involve trees with just two levels. Fix this with unconditionally updating the CPU of the child event before considering to early return while updating a queued event with an unchanged expiry value. Fixes: 7ee988770326 ("timers: Implement the hierarchical pull model") Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Link: https://lore.kernel.org/r/Zg2Ct6M2RJAYHgCB@localhost.localdomain
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-06 22:39:20 +0000