Linux kernel
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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.
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Pull irq fixes from Thomas Gleixner:
"Two fixes for the interrupt subsystem:
- Make the handling of the firmware node consistent and do not free
the node after the domain has been created successfully. The core
code stores a pointer to it which can lead to a use after free or
double free.
This used to "work" because the pointer was not stored when the
initial code was written, but at some point later it was required
to store it. Of course nobody noticed that the existing users break
that way.
- Handle affinity setting on inactive interrupts correctly when
hierarchical irq domains are enabled.
When interrupts are inactive with the modern hierarchical irqdomain
design, the interrupt chips are not necessarily in a state where
affinity changes can be handled. The legacy irq chip design allowed
this because interrupts are immediately fully initialized at
allocation time. X86 has a hacky workaround for this, but other
implementations do not.
This cased malfunction on GIC-V3. Instead of playing whack a mole
to find all affected drivers, change the core code to store the
requested affinity setting and then establish it when the interrupt
is allocated, which makes the X86 hack go away"
* tag 'irq-urgent-2020-07-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq/affinity: Handle affinity setting on inactive interrupts correctly
irqdomain/treewide: Keep firmware node unconditionally allocated
Pull USB fixes from Greg KH:
"Here are a few small USB fixes, and one thunderbolt fix, for 5.8-rc6.
Nothing huge in here, just the normal collection of gadget, dwc2/3,
serial, and other minor USB driver fixes and id additions. Full
details are in the shortlog.
All of these have been in linux-next for a while with no reported
issues"
* tag 'usb-5.8-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
USB: serial: iuu_phoenix: fix memory corruption
USB: c67x00: fix use after free in c67x00_giveback_urb
usb: gadget: function: fix missing spinlock in f_uac1_legacy
usb: gadget: udc: atmel: fix uninitialized read in debug printk
usb: gadget: udc: atmel: remove outdated comment in usba_ep_disable()
usb: dwc2: Fix shutdown callback in platform
usb: cdns3: trace: fix some endian issues
usb: cdns3: ep0: fix some endian issues
usb: gadget: udc: gr_udc: fix memleak on error handling path in gr_ep_init()
usb: gadget: fix langid kernel-doc warning in usbstring.c
usb: dwc3: pci: add support for the Intel Jasper Lake
usb: dwc3: pci: add support for the Intel Tiger Lake PCH -H variant
usb: chipidea: core: add wakeup support for extcon
USB: serial: option: add Quectel EG95 LTE modem
thunderbolt: Fix path indices used in USB3 tunnel discovery
USB: serial: ch341: add new Product ID for CH340
USB: serial: option: add GosunCn GM500 series
USB: serial: cypress_m8: enable Simply Automated UPB PIM
Setting interrupt affinity on inactive interrupts is inconsistent when
hierarchical irq domains are enabled. The core code should just store the
affinity and not call into the irq chip driver for inactive interrupts
because the chip drivers may not be in a state to handle such requests.
X86 has a hacky workaround for that but all other irq chips have not which
causes problems e.g. on GIC V3 ITS.
Instead of adding more ugly hacks all over the place, solve the problem in
the core code. If the affinity is set on an inactive interrupt then:
- Store it in the irq descriptors affinity mask
- Update the effective affinity to reflect that so user space has
a consistent view
- Don't call into the irq chip driver
This is the core equivalent of the X86 workaround and works correctly
because the affinity setting is established in the irq chip when the
interrupt is activated later on.
Note, that this is only effective when hierarchical irq domains are enabled
by the architecture. Doing it unconditionally would break legacy irq chip
implementations.
For hierarchial irq domains this works correctly as none of the drivers can
have a dependency on affinity setting in inactive state by design.
Remove the X86 workaround as it is not longer required.
Fixes: 02edee152d6e ("x86/apic/vector: Ignore set_affinity call for inactive interrupts")
Reported-by: Ali Saidi <alisaidi@amazon.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Ali Saidi <alisaidi@amazon.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200529015501.15771-1-alisaidi@amazon.com
Link: https://lkml.kernel.org/r/877dv2rv25.fsf@nanos.tec.linutronix.de
Pull dma-mapping fixes from Christoph Hellwig:
"Ensure we always have fully addressable memory in the dma coherent
pool (Nicolas Saenz Julienne)"
* tag 'dma-mapping-5.8-6' of git://git.infradead.org/users/hch/dma-mapping:
dma-pool: do not allocate pool memory from CMA
dma-pool: make sure atomic pool suits device
dma-pool: introduce dma_guess_pool()
dma-pool: get rid of dma_in_atomic_pool()
dma-direct: provide function to check physical memory area validity
Johan writes:
USB-serial fixes for 5.8-rc6
Here's a fix for 5.8 addressing a long-standing bug in iuu_phoenix.
* tag 'usb-serial-5.8-rc6' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial:
USB: serial: iuu_phoenix: fix memory corruption
Quite some non OF/ACPI users of irqdomains allocate firmware nodes of type
IRQCHIP_FWNODE_NAMED or IRQCHIP_FWNODE_NAMED_ID and free them right after
creating the irqdomain. The only purpose of these FW nodes is to convey
name information. When this was introduced the core code did not store the
pointer to the node in the irqdomain. A recent change stored the firmware
node pointer in irqdomain for other reasons and missed to notice that the
usage sites which do the alloc_fwnode/create_domain/free_fwnode sequence
are broken by this. Storing a dangling pointer is dangerous itself, but in
case that the domain is destroyed later on this leads to a double free.
Remove the freeing of the firmware node after creating the irqdomain from
all affected call sites to cure this.
Fixes: 711419e504eb ("irqdomain: Add the missing assignment of domain->fwnode for named fwnode")
Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/873661qakd.fsf@nanos.tec.linutronix.de
Pull SCSI fix from James Bottomley:
"One small driver fix. Although the one liner makes it sound like a
cosmetic change, it's a regression fix for the megaraid_sas driver"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: megaraid_sas: Remove undefined ENABLE_IRQ_POLL macro
There is no guarantee to CMA's placement, so allocating a zone specific
atomic pool from CMA might return memory from a completely different
memory zone. So stop using it.
Fixes: c84dc6e68a1d ("dma-pool: add additional coherent pools to map to gfp mask")
Reported-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Tested-by: Jeremy Linton <jeremy.linton@arm.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Felipe writes:
USB: fixes for v5.8-rc3
Adding support for recent Intel devices (Tiger Lake and Jasper Lake)
on dwc3. We have some endianess fixes in cdns3, a memleak fix in
gr_udc and lock API usage fix in the legacy f_uac1
Signed-off-by: Felipe Balbi <balbi@kernel.org>
* tag 'fixes-for-v5.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb:
usb: gadget: function: fix missing spinlock in f_uac1_legacy
usb: gadget: udc: atmel: fix uninitialized read in debug printk
usb: gadget: udc: atmel: remove outdated comment in usba_ep_disable()
usb: dwc2: Fix shutdown callback in platform
usb: cdns3: trace: fix some endian issues
usb: cdns3: ep0: fix some endian issues
usb: gadget: udc: gr_udc: fix memleak on error handling path in gr_ep_init()
usb: gadget: fix langid kernel-doc warning in usbstring.c
usb: dwc3: pci: add support for the Intel Jasper Lake
usb: dwc3: pci: add support for the Intel Tiger Lake PCH -H variant
The driver would happily overwrite its write buffer with user data in
256 byte increments due to a removed buffer-space sanity check.
Fixes: 5fcf62b0f1f2 ("tty: iuu_phoenix: fix locking.")
Cc: stable <stable@vger.kernel.org> # 2.6.31
Signed-off-by: Johan Hovold <johan@kernel.org>
Pull hwmon fixes from Guenter Roeck:
- Using SCT on some Tohsiba drives causes firmware hangs. Disable its
use in the drivetemp driver.
- Handle potential buffer overflows in scmi and aspeed-pwm-tacho
driver.
- Energy reporting does not work well on all AMD CPUs. Restrict
amd_energy to known working models.
- Enable reading the CPU temperature on NCT6798D using undocumented
registers.
- Fix read errors seen if PEC is enabled in adm1275 driver.
- Fix setting the pwm1_enable in emc2103 driver.
* tag 'hwmon-for-v5.8-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
hwmon: (drivetemp) Avoid SCT usage on Toshiba DT01ACA family drives
hwmon: (scmi) Fix potential buffer overflow in scmi_hwmon_probe()
hwmon: (nct6775) Accept PECI Calibration as temperature source for NCT6798D
hwmon: (adm1275) Make sure we are reading enough data for different chips
hwmon: (emc2103) fix unable to change fan pwm1_enable attribute
hwmon: (amd_energy) match for supported models
hwmon: (aspeed-pwm-tacho) Avoid possible buffer overflow
As the ENABLE_IRQ_POLL macro is undefined, the check for ENABLE_IRQ_POLL
macro in ISR will always be false. This leads to irq polling being
non-functional.
Remove ENABLE_IRQ_POLL check from ISR.
Link: https://lore.kernel.org/r/20200715120153.20512-1-chandrakanth.patil@broadcom.com
Fixes: a6ffd5bf6819 ("scsi: megaraid_sas: Call disable_irq from process IRQ")
Cc: <stable@vger.kernel.org> # v5.3+
Signed-off-by: Chandrakanth Patil <chandrakanth.patil@broadcom.com>
Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>