Linux kernel
============
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https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Clone this repository
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Pull irq fix from Borislav Petkov:
- Fix locking when accessing device MSI descriptors
* tag 'irq_urgent_for_v5.18_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
bus: fsl-mc-msi: Fix MSI descriptor mutex lock for msi_first_desc()
Pull driver core fixes from Greg KH:
"Here are some small driver core and kernfs fixes for some reported
problems. They include:
- kernfs regression that is causing oopses in 5.17 and newer releases
- topology sysfs fixes for a few small reported problems.
All of these have been in linux-next for a while with no reported
issues"
* tag 'driver-core-5.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
kernfs: fix NULL dereferencing in kernfs_remove
topology: Fix up build warning in topology_is_visible()
arch_topology: Do not set llc_sibling if llc_id is invalid
topology: make core_mask include at least cluster_siblings
topology/sysfs: Hide PPIN on systems that do not support it.
Commit e8604b1447b4 introduced a call to the helper function
msi_first_desc(), which needs MSI descriptor mutex lock before
call. However, the required mutex lock was not added. This results in
lockdep assertion:
WARNING: CPU: 4 PID: 119 at kernel/irq/msi.c:274 msi_first_desc+0xd0/0x10c
msi_first_desc+0xd0/0x10c
fsl_mc_msi_domain_alloc_irqs+0x7c/0xc0
fsl_mc_populate_irq_pool+0x80/0x3cc
Fix this by adding the mutex lock and unlock around the function call.
Fixes: e8604b1447b4 ("bus: fsl-mc-msi: Simplify MSI descriptor handling")
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20220412075636.755454-1-shinichiro.kawasaki@wdc.com
Pull char/misc driver fixes from Greg KH:
"Here are a small number of char/misc/other driver fixes for 5.18-rc5
Nothing major in here, this is mostly IIO driver fixes along with some
other small things:
- at25 driver fix for systems without a dma-able stack
- phy driver fixes for reported issues
- binder driver fixes for reported issues
All of these have been in linux-next without any reported problems"
* tag 'char-misc-5.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (31 commits)
eeprom: at25: Use DMA safe buffers
binder: Gracefully handle BINDER_TYPE_FDA objects with num_fds=0
binder: Address corner cases in deferred copy and fixup
phy: amlogic: fix error path in phy_g12a_usb3_pcie_probe()
iio: imu: inv_icm42600: Fix I2C init possible nack
iio: dac: ltc2688: fix voltage scale read
interconnect: qcom: sdx55: Drop IP0 interconnects
interconnect: qcom: sc7180: Drop IP0 interconnects
phy: ti: Add missing pm_runtime_disable() in serdes_am654_probe
phy: mapphone-mdm6600: Fix PM error handling in phy_mdm6600_probe
phy: ti: omap-usb2: Fix error handling in omap_usb2_enable_clocks
bus: mhi: host: pci_generic: Flush recovery worker during freeze
bus: mhi: host: pci_generic: Add missing poweroff() PM callback
phy: ti: tusb1210: Fix an error handling path in tusb1210_probe()
phy: samsung: exynos5250-sata: fix missing device put in probe error paths
phy: samsung: Fix missing of_node_put() in exynos_sata_phy_probe
phy: ti: Fix missing of_node_put in ti_pipe3_get_sysctrl()
phy: ti: tusb1210: Make tusb1210_chg_det_states static
iio:dac:ad3552r: Fix an IS_ERR() vs NULL check
iio: sx9324: Fix default precharge internal resistance register
...
kernfs_remove supported NULL kernfs_node param to bail out but revent
per-fs lock change introduced regression that dereferencing the
param without NULL check so kernel goes crash.
This patch checks the NULL kernfs_node in kernfs_remove and if so,
just return.
Quote from bug report by Jirka
```
The bug is triggered by running NAS Parallel benchmark suite on
SuperMicro servers with 2x Xeon(R) Gold 6126 CPU. Here is the error
log:
[ 247.035564] BUG: kernel NULL pointer dereference, address: 0000000000000008
[ 247.036009] #PF: supervisor read access in kernel mode
[ 247.036009] #PF: error_code(0x0000) - not-present page
[ 247.036009] PGD 0 P4D 0
[ 247.036009] Oops: 0000 [#1] PREEMPT SMP PTI
[ 247.058060] CPU: 1 PID: 6546 Comm: umount Not tainted
5.16.0393c3714081a53795bbff0e985d24146def6f57f+ #16
[ 247.058060] Hardware name: Supermicro Super Server/X11DDW-L, BIOS
2.0b 03/07/2018
[ 247.058060] RIP: 0010:kernfs_remove+0x8/0x50
[ 247.058060] Code: 4c 89 e0 5b 5d 41 5c 41 5d 41 5e c3 49 c7 c4 f4
ff ff ff eb b2 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 0f 1f 44 00 00
41 54 55 <48> 8b 47 08 48 89 fd 48 85 c0 48 0f 44 c7 4c 8b 60 50 49 83
c4 60
[ 247.058060] RSP: 0018:ffffbbfa48a27e48 EFLAGS: 00010246
[ 247.058060] RAX: 0000000000000001 RBX: ffffffff89e31f98 RCX: 0000000080200018
[ 247.058060] RDX: 0000000080200019 RSI: fffff6760786c900 RDI: 0000000000000000
[ 247.058060] RBP: ffffffff89e31f98 R08: ffff926b61b24d00 R09: 0000000080200018
[ 247.122048] R10: ffff926b61b24d00 R11: ffff926a8040c000 R12: ffff927bd09a2000
[ 247.122048] R13: ffffffff89e31fa0 R14: dead000000000122 R15: dead000000000100
[ 247.122048] FS: 00007f01be0a8c40(0000) GS:ffff926fa8e40000(0000)
knlGS:0000000000000000
[ 247.122048] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 247.122048] CR2: 0000000000000008 CR3: 00000001145c6003 CR4: 00000000007706e0
[ 247.122048] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 247.122048] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 247.122048] PKRU: 55555554
[ 247.122048] Call Trace:
[ 247.122048] <TASK>
[ 247.122048] rdt_kill_sb+0x29d/0x350
[ 247.122048] deactivate_locked_super+0x36/0xa0
[ 247.122048] cleanup_mnt+0x131/0x190
[ 247.122048] task_work_run+0x5c/0x90
[ 247.122048] exit_to_user_mode_prepare+0x229/0x230
[ 247.122048] syscall_exit_to_user_mode+0x18/0x40
[ 247.122048] do_syscall_64+0x48/0x90
[ 247.122048] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 247.122048] RIP: 0033:0x7f01be2d735b
```
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215696
Link: https://lore.kernel.org/lkml/CAE4VaGDZr_4wzRn2___eDYRtmdPaGGJdzu_LCSkJYuY9BEO3cw@mail.gmail.com/
Fixes: 393c3714081a (kernfs: switch global kernfs_rwsem lock to per-fs lock)
Cc: stable@vger.kernel.org
Reported-by: Jirka Hladky <jhladky@redhat.com>
Tested-by: Jirka Hladky <jhladky@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Minchan Kim <minchan@kernel.org>
Link: https://lore.kernel.org/r/20220427172152.3505364-1-minchan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull tty/serial fixes from Greg KH:
"Here are some small serial driver fixes, and a larger number of GSM
line discipline fixes for 5.18-rc5.
These include:
- lots of tiny n_gsm fixes for issues to resolve a number of reported
problems. Seems that people are starting to actually use this code
again.
- 8250 driver fixes for some devices
- imx serial driver fix
- amba-pl011 driver fix
All of these have been in linux-next for a while with no reported
issues"
* tag 'tty-5.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (27 commits)
tty: n_gsm: fix sometimes uninitialized warning in gsm_dlci_modem_output()
serial: 8250: Correct the clock for EndRun PTP/1588 PCIe device
serial: 8250: Also set sticky MCR bits in console restoration
tty: n_gsm: fix software flow control handling
tty: n_gsm: fix invalid use of MSC in advanced option
tty: n_gsm: fix broken virtual tty handling
Revert "serial: sc16is7xx: Clear RS485 bits in the shutdown"
tty: n_gsm: fix missing update of modem controls after DLCI open
serial: 8250: Fix runtime PM for start_tx() for empty buffer
serial: imx: fix overrun interrupts in DMA mode
serial: amba-pl011: do not time out prematurely when draining tx fifo
tty: n_gsm: fix incorrect UA handling
tty: n_gsm: fix reset fifo race condition
tty: n_gsm: fix missing tty wakeup in convergence layer type 2
tty: n_gsm: fix wrong signal octets encoding in MSC
tty: n_gsm: fix wrong command frame length field encoding
tty: n_gsm: fix wrong command retry handling
tty: n_gsm: fix missing explicit ldisc flush
tty: n_gsm: fix wrong DLCI release order
tty: n_gsm: fix insufficient txframe size
...
Pull set of IIO fixes for 5.18 from Jonathan Cameron:
"1st set of IIO fixes for the 5.18 cycle
ad3552r:
- Fix a bug with error codes being stored in unsigned local variable.
- Fix IS_ERR when value is either NULL or not rather than ERR_PTR
ad5446
- Fix shifting of read_raw value.
ad5592r
- Fix missing return value being set for a fwnode property read.
ad7280a
- Wrong variable being used to set thresholds.
admv8818
- Kconfig dependency fix.
ak8975
- Missing regulator disable in error path.
bmi160
- Disable regulators in an error path.
dac5571
- Fix chip id detection for devices with OF bindings.
inv_icm42600
- Handle a case of a missing I2C NACK during initially configuration.
ltc2688
- Fix voltage scaling where integer part was written twice and
decimal part not at all.
scd4x
- Handle error before using value.
sx9310
- Device property parsing against indio_dev->dev.of_node which
hasn't been set yet.
sx9324
- Fix hardware gain related maths.
- Wrong defaults for precharge internal resistance register."
* tag 'iio-fixes-for-5.18a' of https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio:
iio: imu: inv_icm42600: Fix I2C init possible nack
iio: dac: ltc2688: fix voltage scale read
iio:dac:ad3552r: Fix an IS_ERR() vs NULL check
iio: sx9324: Fix default precharge internal resistance register
iio: dac: ad5446: Fix read_raw not returning set value
iio: magnetometer: ak8975: Fix the error handling in ak8975_power_on()
iio:proximity:sx9324: Fix hardware gain read/write
iio:proximity:sx_common: Fix device property parsing on DT systems
iio: adc: ad7280a: Fix wrong variable used when setting thresholds.
iio:filter:admv8818: select REGMAP_SPI for ADMV8818
iio: dac: ad5592r: Fix the missing return value.
iio: dac: dac5571: Fix chip id detection for OF devices
iio:imu:bmi160: disable regulator in error path
iio: scd4x: check return of scd4x_write_and_fetch
iio: dac: ad3552r: fix signedness bug in ad3552r_reset()
Commit aa63a74d4535 ("topology/sysfs: Hide PPIN on systems that do not
support it.") caused a build warning on some configurations:
drivers/base/topology.c: In function 'topology_is_visible':
drivers/base/topology.c:158:24: warning: unused variable 'dev' [-Wunused-variable]
158 | struct device *dev = kobj_to_dev(kobj);
Fix this up by getting rid of the variable entirely.
Fixes: aa63a74d4535 ("topology/sysfs: Hide PPIN on systems that do not support it.")
Cc: Tony Luck <tony.luck@intel.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Link: https://lore.kernel.org/r/20220422062653.3899972-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull scheduler fix from Borislav Petkov:
- Fix a corner case when calculating sched runqueue variables
That fix also removes a check for a zero divisor in the code, without
mentioning it. Vincent clarified that it's ok after I whined about it:
https://lore.kernel.org/all/CAKfTPtD2QEyZ6ADd5WrwETMOX0XOwJGnVddt7VHgfURdqgOS-Q@mail.gmail.com/
* tag 'sched_urgent_for_v5.18_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/pelt: Fix attach_entity_load_avg() corner case
Pull USB fixes from Greg KH:
"Here are a number of small USB driver fixes for 5.18-rc5 for some
reported issues and new quirks. They include:
- dwc3 driver fixes
- xhci driver fixes
- typec driver fixes
- new usb-serial driver ids
- added new USB devices to existing quirk tables
- other tiny fixes
All of these have been in linux-next for a while with no reported
issues"
* tag 'usb-5.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (31 commits)
usb: phy: generic: Get the vbus supply
usb: dwc3: gadget: Return proper request status
usb: dwc3: pci: add support for the Intel Meteor Lake-P
usb: dwc3: core: Only handle soft-reset in DCTL
usb: gadget: configfs: clear deactivation flag in configfs_composite_unbind()
usb: misc: eud: Fix an error handling path in eud_probe()
usb: core: Don't hold the device lock while sleeping in do_proc_control()
usb: dwc3: Try usb-role-switch first in dwc3_drd_init
usb: dwc3: core: Fix tx/rx threshold settings
usb: mtu3: fix USB 3.0 dual-role-switch from device to host
xhci: Enable runtime PM on second Alderlake controller
usb: dwc3: fix backwards compat with rockchip devices
dt-bindings: usb: samsung,exynos-usb2: add missing required reg
usb: misc: fix improper handling of refcount in uss720_probe()
USB: Fix ehci infinite suspend-resume loop issue in zhaoxin
usb: typec: tcpm: Fix undefined behavior due to shift overflowing the constant
usb: typec: rt1719: Fix build error without CONFIG_POWER_SUPPLY
usb: typec: ucsi: Fix role swapping
usb: typec: ucsi: Fix reuse of completion structure
usb: xhci: tegra:Fix PM usage reference leak of tegra_xusb_unpowergate_partitions
...
'size' may be used uninitialized in gsm_dlci_modem_output() if called with
an adaption that is neither 1 nor 2. The function is currently only called
by gsm_modem_upd_via_data() and only for adaption 2.
Properly handle every invalid case by returning -EINVAL to silence the
compiler warning and avoid future regressions.
Fixes: c19ffe00fed6 ("tty: n_gsm: fix invalid use of MSC in advanced option")
Cc: stable@vger.kernel.org
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Daniel Starke <daniel.starke@siemens.com>
Link: https://lore.kernel.org/r/20220425104726.7986-1-daniel.starke@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reading EEPROM fails with following warning:
[ 16.357496] ------------[ cut here ]------------
[ 16.357529] fsl_spi b01004c0.spi: rejecting DMA map of vmalloc memory
[ 16.357698] WARNING: CPU: 0 PID: 371 at include/linux/dma-mapping.h:326 fsl_spi_cpm_bufs+0x2a0/0x2d8
[ 16.357775] CPU: 0 PID: 371 Comm: od Not tainted 5.16.11-s3k-dev-01743-g19beecbfe9d6-dirty #109
[ 16.357806] NIP: c03fbc9c LR: c03fbc9c CTR: 00000000
[ 16.357825] REGS: e68d9b20 TRAP: 0700 Not tainted (5.16.11-s3k-dev-01743-g19beecbfe9d6-dirty)
[ 16.357849] MSR: 00029032 <EE,ME,IR,DR,RI> CR: 24002282 XER: 00000000
[ 16.357931]
[ 16.357931] GPR00: c03fbc9c e68d9be0 c26d06a0 00000039 00000001 c0d36364 c0e96428 00000027
[ 16.357931] GPR08: 00000001 00000000 00000023 3fffc000 24002282 100d3dd6 100a2ffc 00000000
[ 16.357931] GPR16: 100cd280 100b0000 00000000 aff54f7e 100d0000 100d0000 00000001 100cf328
[ 16.357931] GPR24: 100cf328 00000000 00000003 e68d9e30 c156b410 e67ab4c0 e68d9d38 c24ab278
[ 16.358253] NIP [c03fbc9c] fsl_spi_cpm_bufs+0x2a0/0x2d8
[ 16.358292] LR [c03fbc9c] fsl_spi_cpm_bufs+0x2a0/0x2d8
[ 16.358325] Call Trace:
[ 16.358336] [e68d9be0] [c03fbc9c] fsl_spi_cpm_bufs+0x2a0/0x2d8 (unreliable)
[ 16.358388] [e68d9c00] [c03fcb44] fsl_spi_bufs.isra.0+0x94/0x1a0
[ 16.358436] [e68d9c20] [c03fd970] fsl_spi_do_one_msg+0x254/0x3dc
[ 16.358483] [e68d9cb0] [c03f7e50] __spi_pump_messages+0x274/0x8a4
[ 16.358529] [e68d9ce0] [c03f9d30] __spi_sync+0x344/0x378
[ 16.358573] [e68d9d20] [c03fb52c] spi_sync+0x34/0x60
[ 16.358616] [e68d9d30] [c03b4dec] at25_ee_read+0x138/0x1a8
[ 16.358667] [e68d9e50] [c04a8fb8] bin_attr_nvmem_read+0x98/0x110
[ 16.358725] [e68d9e60] [c0204b14] kernfs_fop_read_iter+0xc0/0x1fc
[ 16.358774] [e68d9e80] [c0168660] vfs_read+0x284/0x410
[ 16.358821] [e68d9f00] [c016925c] ksys_read+0x6c/0x11c
[ 16.358863] [e68d9f30] [c00160e0] ret_from_syscall+0x0/0x28
...
[ 16.359608] ---[ end trace a4ce3e34afef0cb5 ]---
[ 16.359638] fsl_spi b01004c0.spi: unable to map tx dma
This is due to the AT25 driver using buffers on stack, which is not
possible with CONFIG_VMAP_STACK.
As mentionned in kernel Documentation (Documentation/spi/spi-summary.rst):
- Follow standard kernel rules, and provide DMA-safe buffers in
your messages. That way controller drivers using DMA aren't forced
to make extra copies unless the hardware requires it (e.g. working
around hardware errata that force the use of bounce buffering).
Modify the driver to use a buffer located in the at25 device structure
which is allocated via kmalloc during probe.
Protect writes in this new buffer with the driver's mutex.
Fixes: b587b13a4f67 ("[PATCH] SPI eeprom driver")
Cc: stable <stable@kernel.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/230a9486fc68ea0182df46255e42a51099403642.1648032613.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>