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Linux kernel
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the problems which may result by upgrading your kernel.
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Pull RISC-V fixes from Paul Walmsley:
"Two fixes for RISC-V:
- Clear FP registers during boot when FP support is present, rather
than when they aren't present
- Move the header files associated with the SiFive L2 cache
controller to drivers/soc (where the code was recently moved)"
* tag 'riscv/for-v5.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: Fixup obvious bug for fp-regs reset
riscv: move sifive_l2_cache.h to include/soc
Pull iommu fixes from Joerg Roedel:
- Two fixes for VT-d and generic IOMMU code to fix teardown on error
handling code paths.
- Patch for the Intel VT-d driver to fix handling of non-PCI devices
- Fix W=1 compile warning in dma-iommu code
* tag 'iommu-fixes-v5.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
iommu/dma: fix variable 'cookie' set but not used
iommu/vt-d: Unlink device if failed to add to group
iommu: Remove device link to group on failure
iommu/vt-d: Fix adding non-PCI devices to Intel IOMMU
CSR_MISA is defined in Privileged Architectures' spec: 3.1.1 Machine
ISA Register misa. Every bit:1 indicate a feature, so we should beqz
reset_done when there is no F/D bit in csr_misa register.
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
[paul.walmsley@sifive.com: fix typo in commit message]
Fixes: 9e80635619b51 ("riscv: clear the instruction cache and all registers when booting")
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Pull i2c fixes from Wolfram Sang:
"Two driver bugfixes, a documentation fix, and a removal of a spec
violation for the bus recovery algorithm in the core"
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: fix bus recovery stop mode timing
i2c: bcm2835: Store pointer to bus clock
dt-bindings: i2c: at91: fix i2c-sda-hold-time-ns documentation for sam9x60
i2c: at91: fix clk_offset for sam9x60
The commit c18647900ec8 ("iommu/dma: Relax locking in
iommu_dma_prepare_msi()") introduced a compliation warning,
drivers/iommu/dma-iommu.c: In function 'iommu_dma_prepare_msi':
drivers/iommu/dma-iommu.c:1206:27: warning: variable 'cookie' set but
not used [-Wunused-but-set-variable]
struct iommu_dma_cookie *cookie;
^~~~~~
Fixes: c18647900ec8 ("iommu/dma: Relax locking in iommu_dma_prepare_msi()")
Signed-off-by: Qian Cai <cai@lca.pw>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The commit 9209fb51896f ("riscv: move sifive_l2_cache.c to drivers/soc")
moves the sifive L2 cache driver to driver/soc. It did not move the
header file along with the driver. Therefore this patch moves the header
file to driver/soc
Signed-off-by: Yash Shah <yash.shah@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
[paul.walmsley@sifive.com: updated to fix the include guard]
Fixes: 9209fb51896f ("riscv: move sifive_l2_cache.c to drivers/soc")
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Pull thread fixes from Christian Brauner:
"This contains a series of patches to fix CLONE_SETTLS when used with
clone3().
The clone3() syscall passes the tls argument through struct clone_args
instead of a register. This means, all architectures that do not
implement copy_thread_tls() but still support CLONE_SETTLS via
copy_thread() expecting the tls to be located in a register argument
based on clone() are currently unfortunately broken. Their tls value
will be garbage.
The patch series fixes this on all architectures that currently define
__ARCH_WANT_SYS_CLONE3. It also adds a compile-time check to ensure
that any architecture that enables clone3() in the future is forced to
also implement copy_thread_tls().
My ultimate goal is to get rid of the copy_thread()/copy_thread_tls()
split and just have copy_thread_tls() at some point in the not too
distant future (Maybe even renaming copy_thread_tls() back to simply
copy_thread() once the old function is ripped from all arches). This
is dependent now on all arches supporting clone3().
While all relevant arches do that now there are still four missing:
ia64, m68k, sh and sparc. They have the system call reserved, but not
implemented. Once they all implement clone3() we can get rid of
ARCH_WANT_SYS_CLONE3 and HAVE_COPY_THREAD_TLS.
This series also includes a minor fix for the arm64 uapi headers which
caused __NR_clone3 to be missing from the exported user headers.
Unfortunately the series came in a little late especially given that
it touches a range of architectures. Due to the holidays not all arch
maintainers responded in time probably due to their backlog. Will and
Arnd have thankfully acked the arm specific changes.
Given that the changes are straightforward and rather minimal combined
with the fact the that clone3() with CLONE_SETTLS is broken I decided
to send them post rc3 nonetheless"
* tag 'clone3-tls-v5.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
um: Implement copy_thread_tls
clone3: ensure copy_thread_tls is implemented
xtensa: Implement copy_thread_tls
riscv: Implement copy_thread_tls
parisc: Implement copy_thread_tls
arm: Implement copy_thread_tls
arm64: Implement copy_thread_tls
arm64: Move __ARCH_WANT_SYS_CLONE3 definition to uapi headers
The I2C specification states that tsu:sto for standard mode timing must
be at minimum 4us. Pictographically, this is:
SCL: ____/~~~~~~~~~
SDA: _________/~~~~
->| |<- 4us minimum
We are currently waiting 2.5us between asserting SCL and SDA, which is
in violation of the standard. Adjust the timings to ensure that we meet
what is stipulated as the minimum timings to ensure that all devices
correctly interpret the STOP bus transition.
This is more important than trying to generate a square wave with even
duty cycle.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
If the device fails to be added to the group, make sure to unlink the
reference before returning.
Signed-off-by: Jon Derrick <jonathan.derrick@intel.com>
Fixes: 39ab9555c2411 ("iommu: Add sysfs bindings for struct iommu_device")
Acked-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Pull HID fix from Jiri Kosina:
"A regression fix for EPOLLOUT handling in hidraw and uhid"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid:
HID: hidraw, uhid: Always report EPOLLOUT
This is required for clone3 which passes the TLS value through a
struct rather than a register.
Signed-off-by: Amanieu d'Antras <amanieu@gmail.com>
Cc: linux-um@lists.infradead.org
Cc: <stable@vger.kernel.org> # 5.3.x
Link: https://lore.kernel.org/r/20200104123928.1048822-1-amanieu@gmail.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
The commit bebff81fb8b9 ("i2c: bcm2835: Model Divider in CCF") introduced
a NULL pointer dereference on driver unload. It seems that we can't fetch
the bus clock via devm_clk_get in bcm2835_i2c_remove. As an alternative
approach store a pointer to the bus clock in the private driver structure.
Fixes: bebff81fb8b9 ("i2c: bcm2835: Model Divider in CCF")
Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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