tjh.dev
Linux kernel
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If create a loop device with a backing NVMe SSD, current loop device
driver doesn't correctly set its queue's limits.discard_granularity and
leaves it as 0. If a discard request at LBA 0 on this loop device, in
__blkdev_issue_discard() the calculated req_sects will be 0, and a zero
length discard request will trigger a BUG() panic in generic block layer
code at block/blk-mq.c:563.
[ 955.565006][ C39] ------------[ cut here ]------------
[ 955.559660][ C39] invalid opcode: 0000 [#1] SMP NOPTI
[ 955.622171][ C39] CPU: 39 PID: 248 Comm: ksoftirqd/39 Tainted: G E 5.8.0-default+ #40
[ 955.622171][ C39] Hardware name: Lenovo ThinkSystem SR650 -[7X05CTO1WW]-/-[7X05CTO1WW]-, BIOS -[IVE160M-2.70]- 07/17/2020
[ 955.622175][ C39] RIP: 0010:blk_mq_end_request+0x107/0x110
[ 955.622177][ C39] Code: 48 8b 03 e9 59 ff ff ff 48 89 df 5b 5d 41 5c e9 9f ed ff ff 48 8b 35 98 3c f4 00 48 83 c7 10 48 83 c6 19 e8 cb 56 c9 ff eb cb <0f> 0b 0f 1f 80 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41 56 41 54
[ 955.622179][ C39] RSP: 0018:ffffb1288701fe28 EFLAGS: 00010202
[ 955.749277][ C39] RAX: 0000000000000001 RBX: ffff956fffba5080 RCX: 0000000000004003
[ 955.749278][ C39] RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000000
[ 955.749279][ C39] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
[ 955.749279][ C39] R10: ffffb1288701fd28 R11: 0000000000000001 R12: ffffffffa8e05160
[ 955.749280][ C39] R13: 0000000000000004 R14: 0000000000000004 R15: ffffffffa7ad3a1e
[ 955.749281][ C39] FS: 0000000000000000(0000) GS:ffff95bfbda00000(0000) knlGS:0000000000000000
[ 955.749282][ C39] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 955.749282][ C39] CR2: 00007f6f0ef766a8 CR3: 0000005a37012002 CR4: 00000000007606e0
[ 955.749283][ C39] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 955.749284][ C39] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 955.749284][ C39] PKRU: 55555554
[ 955.749285][ C39] Call Trace:
[ 955.749290][ C39] blk_done_softirq+0x99/0xc0
[ 957.550669][ C39] __do_softirq+0xd3/0x45f
[ 957.550677][ C39] ? smpboot_thread_fn+0x2f/0x1e0
[ 957.550679][ C39] ? smpboot_thread_fn+0x74/0x1e0
[ 957.550680][ C39] ? smpboot_thread_fn+0x14e/0x1e0
[ 957.550684][ C39] run_ksoftirqd+0x30/0x60
[ 957.550687][ C39] smpboot_thread_fn+0x149/0x1e0
[ 957.886225][ C39] ? sort_range+0x20/0x20
[ 957.886226][ C39] kthread+0x137/0x160
[ 957.886228][ C39] ? kthread_park+0x90/0x90
[ 957.886231][ C39] ret_from_fork+0x22/0x30
[ 959.117120][ C39] ---[ end trace 3dacdac97e2ed164 ]---
This is the procedure to reproduce the panic,
# modprobe scsi_debug delay=0 dev_size_mb=2048 max_queue=1
# losetup -f /dev/nvme0n1 --direct-io=on
# blkdiscard /dev/loop0 -o 0 -l 0x200
This patch fixes the issue by checking q->limits.discard_granularity in
__blkdev_issue_discard() before composing the discard bio. If the value
is 0, then prints a warning oops information and returns -EOPNOTSUPP to
the caller to indicate that this buggy device driver doesn't support
discard request.
Fixes: 9b15d109a6b2 ("block: improve discard bio alignment in __blkdev_issue_discard()")
Fixes: c52abf563049 ("loop: Better discard support for block devices")
Reported-and-suggested-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Enzo Matsumiya <ematsumiya@suse.com>
Cc: Evan Green <evgreen@chromium.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Xiao Ni <xni@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull hmm updates from Jason Gunthorpe:
"Ralph has been working on nouveau's use of hmm_range_fault() and
migrate_vma() which resulted in this small series. It adds reporting
of the page table order from hmm_range_fault() and some optimization
of migrate_vma():
- Report the size of the page table mapping out of hmm_range_fault().
This makes it easier to establish a large/huge/etc mapping in the
device's page table.
- Allow devices to ignore the invalidations during migration in cases
where the migration is not going to change pages.
For instance migrating pages to a device does not require the
device to invalidate pages already in the device.
- Update nouveau and hmm_tests to use the above"
* tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
mm/hmm/test: use the new migration invalidation
nouveau/svm: use the new migration invalidation
mm/notifier: add migration invalidation type
mm/migrate: add a flags parameter to migrate_vma
nouveau: fix storing invalid ptes
nouveau/hmm: support mapping large sysmem pages
nouveau: fix mapping 2MB sysmem pages
nouveau/hmm: fault one page at a time
mm/hmm: add tests for hmm_pfn_to_map_order()
mm/hmm: provide the page mapping order in hmm_range_fault()
Pull MMC updates from Ulf Hansson:
"MMC core:
- Add a new host cap bit and a corresponding DT property, to support
power cycling of the card by FW at system suspend/resume.
- Fix clock rate setting for SDIO in SDR12/SDR25 speed-mode
- Fix switch to 1/4-bit mode at system suspend/resume for SD-combo
cards
- Convert the mmc-pwrseq DT bindings to the json-schema
- Always allow the card detect uevent to be consumed by userspace
MMC host controllers:
- Convert a few DT bindings to the json-schema
- mtk-sd:
- Add support for command queue through cqhci
- Add support for the MT6779 variant
- renesas_sdhi_internal_dmac:
- Fix dma unmapping in the error path
- sdhci_am654:
- Add support for the AM65x PG2.0 variant
- Extend support for phys/clocks
- sdhci-cadence:
- Drop incorrect HW tuning for SD mode
- sdhci-msm:
- Add support for interconnect bandwidth scaling
- Enable internal voltage control
- Enable low power state for pinctrls
- sdhci-of-at91:
- Ludovic Desroches handovers maintenance to Eugen Hristev
- sdhci-pci-gli:
- Improve clock handling for GL975x
- sdhci-pci-o2micro:
- Add HW tuning for SDR104 mode
- Fix support for O2 host controller Seabird1"
* tag 'mmc-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc: (66 commits)
mmc: mediatek: make function msdc_cqe_disable() static
MAINTAINERS: mmc: sdhci-of-at91: handover maintenance to Eugen Hristev
dt-bindings: mmc: mediatek: Add document for mt6779
mmc: mediatek: command queue support
mmc: mediatek: refine msdc timeout api
mmc: mediatek: add MT6779 MMC driver support
mmc: sdhci-pci-o2micro: Add HW tuning for SDR104 mode
mmc: sdhci-pci-o2micro: Bug fix for O2 host controller Seabird1
mmc: via-sdmmc: use generic power management
memstick: jmb38x_ms: use generic power management
mmc: sdhci-cadence: do not use hardware tuning for SD mode
mmc: sdhci-pci-gli: Set SDR104's clock to 205MHz and enable SSC for GL975x
mmc: cqhci: Fix a print format for the task descriptor
mmc: sdhci-of-arasan: fix timings allocation code
mmc: sdhci: Fix a potential uninitialized variable
dt-bindings: mmc: renesas,sdhi: convert to YAML
dt-bindings: mmc: convert arasan sdhci bindings to yaml
mmc: sdhci: Fix potential null pointer access while accessing vqmmc
mmc: core: Add MMC_CAP2_FULL_PWR_CYCLE_IN_SUSPEND
dt-bindings: mmc: Add full-pwr-cycle-in-suspend property
...
Use the new MMU_NOTIFY_MIGRATE event to skip MMU invalidations of device
private memory and handle the invalidation in the driver as part of
migrating device private memory.
Link: https://lore.kernel.org/r/20200723223004.9586-6-rcampbell@nvidia.com
Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Pull hwmon updates from Guenter Roeck:
"Highlights:
- New driver for Sparx5 SoC temperature sensot
- New driver for Corsair Commander Pro
- MAX20710 support added to max20730 driver
Enhancements:
- max6697: Allow max6581 to create tempX_offset attributes
- gsc (Gateworks System Controller): add 16bit pre-scaled voltage mode
- adm1275: Enable adm1278 ADM1278_TEMP1_EN
- dell-smm: Add Latitude 5480 to fan control whitelist
Fixes:
- adc128d818: Fix advanced configuration register init
- pmbus/core: Use s64 instead of long for calculations to fix
overflow issues with 32-bit architectures
Plus various cleanups in several drivers"
* tag 'hwmon-for-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging: (32 commits)
hwmon: (adc128d818) Fix advanced configuration register init
hwmon: (axi-fan-control) remove duplicate macros
hwmon: (i5k_amb, vt8231) Drop uses of pci_read_config_*() return value
hwmon: (sparx5) Make symbol 's5_temp_match' static
hwmon: (corsair-cpro) add reading pwm values
hwmon: sparx5: Add Sparx5 SoC temperature driver
dt-bindings: hwmon: Add Sparx5 temperature sensor
hwmon: (tmp401) Replace HTTP links with HTTPS ones
hwmon: (lm95234) Replace HTTP links with HTTPS ones
hwmon: (lm90) Replace HTTP links with HTTPS ones
hwmon: (k8temp) Replace HTTP links with HTTPS ones
hwmon: (jc42) Replace HTTP links with HTTPS ones
hwmon: (ina2xx) Replace HTTP links with HTTPS ones
hwmon: (ina209) Replace HTTP links with HTTPS ones
hwmon: Replace HTTP links with HTTPS ones
docs: hwmon: Replace HTTP links with HTTPS ones
hwmon: (adm1025) Replace HTTP links with HTTPS ones
hwmon: add Corsair Commander Pro driver
hwmon: (max6697) Allow max6581 to create tempX_offset
hwmon: (tmmp513) Replace HTTP links with HTTPS links
...
The sparse tool complains as follows:
drivers/mmc/host/mtk-sd.c:2269:6: warning:
symbol 'msdc_cqe_disable' was not declared. Should it be static?
This function is not used outside of mtk-sd.c, so this commit
marks it static.
Fixes: 88bd652b3c74 ("mmc: mediatek: command queue support")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Chun-Hung Wu <chun-hung.wu@mediatek.com>
Link: https://lore.kernel.org/r/20200727171129.2945-1-weiyongjun1@huawei.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Use the new MMU_NOTIFY_MIGRATE event to skip GPU MMU invalidations of
device private memory and handle the invalidation in the driver as part of
migrating device private memory.
Link: https://lore.kernel.org/r/20200723223004.9586-5-rcampbell@nvidia.com
Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Pull Devicetree updates from Rob Herring:
- Improve device links cycle detection and breaking. Add more bindings
for device link dependencies.
- Refactor parsing 'no-map' in __reserved_mem_alloc_size()
- Improve DT unittest 'ranges' and 'dma-ranges' test case to check
differing cell sizes
- Various http to https link conversions
- Add a schema check to prevent 'syscon' from being used by itself
without a more specific compatible
- A bunch more DT binding conversions to schema
* tag 'devicetree-for-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (55 commits)
of: reserved-memory: remove duplicated call to of_get_flat_dt_prop() for no-map node
of: unittest: Use bigger address cells to catch parser regressions
dt-bindings: memory-controllers: Convert mmdc to json-schema
dt-bindings: mtd: Convert imx nand to json-schema
dt-bindings: mtd: Convert gpmi nand to json-schema
dt-bindings: iio: io-channel-mux: Fix compatible string in example code
of: property: Add device link support for pinctrl-0 through pinctrl-8
of: property: Add device link support for multiple DT bindings
dt-bindings: phy: ti: phy-gmii-sel: convert bindings to json-schema
dt-bindings: mux: mux.h: drop a duplicated word
dt-bindings: misc: Convert olpc,xo1.75-ec to json-schema
dt-bindings: aspeed-lpc: Replace HTTP links with HTTPS ones
dt-bindings: drm/bridge: Replace HTTP links with HTTPS ones
drm/tilcdc: Replace HTTP links with HTTPS ones
dt-bindings: iommu: renesas,ipmmu-vmsa: Add r8a774e1 support
dt-bindings: fpga: Replace HTTP links with HTTPS ones
dt-bindings: virtio: Replace HTTP links with HTTPS ones
dt-bindings: media: imx274: Add optional input clock and supplies
dt-bindings: i2c-gpio: Use 'deprecated' keyword on deprecated properties
dt-bindings: interrupt-controller: Fix typos in loongson,liointc.yaml
...
If the operation mode is non-zero and an external reference voltage is set,
first the operation mode is written to the advanced configuration register,
followed by the externel reference enable bit,
resetting the configuration mode to 0.
To fix this, first compose the value of the advanced configuration register
based on the configuration mode and the external reference voltage.
The advanced configuration register is then written to the device,
if it is different from the default register value (0x0).
Signed-off-by: Roy van Doormaal <roy.van.doormaal@prodrive-technologies.com>
Link: https://lore.kernel.org/r/20200728151846.231785-1-roy.van.doormaal@prodrive-technologies.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
As Eugen handles the software for bootloaders and new products, handover
the maintenance to him.
Signed-off-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Acked-by: Eugen Hristev <eugen.hristev@microchip.com>
Link: https://lore.kernel.org/r/20200709085331.8145-1-ludovic.desroches@microchip.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Currently migrate_vma_setup() calls mmu_notifier_invalidate_range_start()
which flushes all device private page mappings whether or not a page is
being migrated to/from device private memory.
In order to not disrupt device mappings that are not being migrated, shift
the responsibility for clearing device private mappings to the device
driver and leave CPU page table unmapping handled by
migrate_vma_setup().
To support this, the caller of migrate_vma_setup() should always set
struct migrate_vma::pgmap_owner to a non NULL value that matches the
device private page->pgmap->owner. This value is then passed to the struct
mmu_notifier_range with a new event type which the driver's invalidation
function can use to avoid device MMU invalidations.
Link: https://lore.kernel.org/r/20200723223004.9586-4-rcampbell@nvidia.com
Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Pull GPIO updates from Linus Walleij:
"This is the bulk of GPIO changes for the v5.9 kernel cycle.
There is nothing too exciting in it, but a new macro that fixes a
build failure on a minor ARM32 platform that appeared yesterday is
part of it so we better merge it.
Core changes:
- Introduce the for_each_requested_gpio() macro to help in dependent
code all over the place. Also patch a few locations to use it while
we are at it.
- Split out the sysfs code into its own file.
- Split out the character device code into its own file, then make a
set of refactorings and improvements to this code. We are setting
the stage to revamp the userspace API a bit in the next cycle.
- Fix a whole slew of kerneldoc that was wrong or missing.
New drivers:
- The PCA953x driver now supports the PCAL9535.
Driver improvements:
- A host of incremental modernizations and improvements to the
PCA953x driver.
- Incremental improvements to the Xilinx Zynq driver.
- Some improvements to the GPIO aggregator driver.
- I ran all over the place switching all threaded and other drivers
requesting their own IRQ while using the core GPIO IRQ helpers to
pass the GPIO irq chip as a template instead of calling the
explicit set-up functions. Next merge window we may retire the old
code altogether"
* tag 'gpio-v5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (97 commits)
gpio: wcove: Request IRQ after all initialisation done
gpio: crystalcove: Free IRQ on error path
gpio: pca953x: Request IRQ after all initialisation done
gpio: don't use same lockdep class for all devm_gpiochip_add_data users
gpio: max732x: Use irqchip template
gpio: stmpe: Move chip registration
gpio: rcar: Use irqchip template
gpio: regmap: fix type clash
gpio: Correct kernel-doc inconsistency
gpio: pci-idio-16: Use irqchip template
gpio: pcie-idio-24: Use irqchip template
gpio: 104-idio-16: Use irqchip template
gpio: 104-idi-48: Use irqchip template
gpio: 104-dio-48e: Use irqchip template
gpio: ws16c48: Use irqchip template
gpio: omap: improve coding style for pin config flags
gpio: dln2: Use irqchip template
gpio: sch: Add a blank line between declaration and code
gpio: sch: changed every 'unsigned' to 'unsigned int'
gpio: ich: changed every 'unsigned' to 'unsigned int'
...
Just use nomap instead of the second call to of_get_flat_dt_prop(). And
change nomap as a bool type due to != NULL operator. Also, correct comment
about node of 'align' -> 'alignment'.
Signed-off-by: Yue Hu <huyue2@yulong.com>
Link: https://lore.kernel.org/r/20200730092353.15644-1-zbestahu@gmail.com
Signed-off-by: Rob Herring <robh@kernel.org>
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