_Generic version allowed __uXX types but that is no longer necessary:
Transitional devices should all use __virtioXX types (and __leXX for
fields not present in the legacy devices).
Modern ones should use __leXX.
_uXX type would be a bug.
Let's prevent that.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
VDPA sim accesses config space as native endian - this is
wrong since it's a modern device and actually uses LE.
It only supports modern guests so we could punt and
just force LE, but let's use the full virtio APIs since people
tend to copy/paste code, and this is not data path anyway.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
We normally expect vdpa to use the modern interface.
However for consistency, let's use same APIs as vhost
for legacy guests.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Some legacy guests just assume features are 0 after reset.
We detect that config space is accessed before features are
set and set features to 0 automatically.
Note: some legacy guests might not even access config space, if this is
reported in the field we might need to catch a kick to handle these.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
mlxbf-tmfifo accesses config space using native types -
which works for it since the legacy virtio native types.
This will break if it ever needs to support modern virtio,
so with new tags previously introduced for virtio net config,
sparse now warns for this in drivers.
Since this is a legacy only device, fix it up using
virtio_legacy_is_little_endian for now.
No functional changes.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Transitional devices should all use __virtioXX types (and __leXX for
fields not present in legacy devices).
Modern ones should use __leXX.
_uXX type would be a bug.
Let's prevent that.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tag config space fields as having virtio endian-ness.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Since this is a modern-only device,
tag config space fields as having little endian-ness.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Since this is a modern-only device,
tag config space fields as having little endian-ness.
TODO: check other uses of __virtioXX types in this header,
should probably be __leXX.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Since this is a modern-only device,
tag config space fields as having little endian-ness.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Since this is a modern-only device,
tag config space fields as having little endian-ness.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Since gpu is a modern-only device,
tag config space fields as having little endian-ness.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Since fs is a modern-only device,
tag config space fields as having little endian-ness.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Since crypto is a modern-only device,
tag config space fields as having little endian-ness.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Tag config space fields as having virtio endian-ness.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Tag config space fields as having virtio endian-ness.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Tag config space fields as having little endian-ness.
Note that balloon is special: LE even when using
the legacy interface.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Tag config space fields as having virtio endian-ness.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Currently all config space fields are of the type __uXX.
This confuses people and some drivers (notably vdpa)
access them using CPU endian-ness - which only
works well for legacy or LE platforms.
Update virtio_cread/virtio_cwrite macros to allow __virtioXX
and __leXX field types. Follow-up patches will convert
config space to use these types.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
virtio_store_mb was built with split ring in mind so it accepts
__virtio16 arguments. Packed ring uses __le16 values, so sparse
complains. It's just a store with some barriers so let's convert it to
a macro, we don't loose too much type safety by doing that.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
balloon uses virtio32_to_cpu instead of cpu_to_virtio32
to convert a native endian number to virtio.
No practical difference but makes sparse warn.
Fix it up.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Ensure we correctly report the stateid and status in the layoutreturn on
close tracepoint.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Tegra HDA has audio data buffer for upto tens of frames, this buffer
can help to avoid underflow. HW will keep issuing new data fetch
request when buffers are not full and current BDL is not done. When SW
disable DMA RUN bit for a stream, HW can't cancel the already issued data
fetch request and hence it can't stop DMA. HW has to wait for all issued
data fetch request get data returned before it stops DMA.
This HW behavior is not in sync with HDA spec which says DMA RUN bit
should be cleared within 1 audio frame. For Tegra, DMA RUN bit was
active for more than one audio frame, due to this the timeout in
snd_hdac_stream_sync function is not helping. When Stream reset set
and clear happens during DMA RUN bit active state it results in Memory
Decode error.
Unfortunately, there is no way to detect when these data accesses have
completed, but testing has shown that a 100us delay between Stream reset
set and clear operation for Tegra avoids the memory decode error.
Therefore, adding a 100us dma stop delay.
Signed-off-by: Mohan Kumar <mkumard@nvidia.com>
Link: https://lore.kernel.org/r/20200805095221.5476-4-mkumard@nvidia.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
A variable dma_stop_delay is added as a new member in hdac_bus
structure to avoid memory decode error incase DMA RUN bit is not
disabled in the given timeout from snd_hdac_stream_sync function and
followed by stream reset which results in memory decode error between
reset set and clear operation.
Signed-off-by: Mohan Kumar <mkumard@nvidia.com>
Link: https://lore.kernel.org/r/20200805095221.5476-3-mkumard@nvidia.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Set chip->align_buffer_size to 1 for Tegra platforms to make the buffer
alignment to be multiple of 128 bytes. This fix is applied as gstreamer
alsasink gets stuck with the default buffer-time and latency-time
parameters with 4 byte buffer alignment.
Signed-off-by: Mohan Kumar <mkumard@nvidia.com>
Link: https://lore.kernel.org/r/20200805095221.5476-2-mkumard@nvidia.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Add SMBus PCI ID on Intel Tiger Lake PCH-H.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Add support for SMBus controller on Intel Emmitsburg PCH. This is the
same IP as used in Cannon Lake and derivatives.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
[wsa: shortened commit message]
Signed-off-by: Wolfram Sang <wsa@kernel.org>
And it has been for a while (since 2012 at least), only it was not
documented. Add it.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Make the Microchip at91 driver the first to use the generic GPIO bus
recovery support from the I2C core and discard the driver implementation.
Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Even if I2C bus GPIO recovery is optional, devm_gpiod_get() can return
-EPROBE_DEFER, so we should at least treat that. This ends up with
i2c_register_adapter() to be able to return -EPROBE_DEFER.
Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Multiple I2C bus drivers use similar bindings to obtain information needed
for I2C recovery. For example, for platforms using device-tree, the
properties look something like this:
&i2c {
...
pinctrl-names = "default", "gpio";
pinctrl-0 = <&pinctrl_i2c_default>;
pinctrl-1 = <&pinctrl_i2c_gpio>;
sda-gpios = <&pio 0 GPIO_ACTIVE_HIGH>;
scl-gpios = <&pio 1 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>;
...
}
For this reason, we can add this common initialization in the core. This
way, other I2C bus drivers will be able to support GPIO recovery just by
providing a pointer to platform's pinctrl and calling i2c_recover_bus()
when SDA is stuck low.
Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
[wsa: inverted one logic for better readability, minor update to kdoc]
Signed-off-by: Wolfram Sang <wsa@kernel.org>
The I2C GPIO bus recovery properties consist of two GPIOS and one extra
pinctrl state ("gpio" or "recovery"). "recovery" pinctrl state is
considered deprecated and "gpio" should be used instead.
Not all are mandatory for recovery.
Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
Reviewed-by: Rob Herring <robh@kernel.org>
[wsa: kept sorting, minor whitespace change]
Signed-off-by: Wolfram Sang <wsa@kernel.org>
If a TAINT_PROPRIETARY_MODULE exports symbol, inherit the taint flag
for all modules importing these symbols, and don't allow loading
symbols from TAINT_PROPRIETARY_MODULE modules if the module previously
imported gplonly symbols. Add a anti-circumvention devices so people
don't accidentally get themselves into trouble this way.
Comment from Greg:
"Ah, the proven-to-be-illegal "GPL Condom" defense :)"
[jeyu: pr_info -> pr_err and pr_warn as per discussion]
Link: http://lore.kernel.org/r/20200730162957.GA22469@lst.de
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
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: 88bd652b3c ("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>
Some ioctls via OSS sequencer API may race and lead to UAF when the
port create and delete are performed concurrently, as spotted by a
couple of syzkaller cases. This patch is an attempt to address it by
serializing the ioctls with the existing register_mutex.
Basically OSS sequencer API is an obsoleted interface and was designed
without much consideration of the concurrency. There are very few
applications with it, and the concurrent performance isn't asked,
hence this "big hammer" approach should be good enough.
Reported-by: syzbot+1a54a94bd32716796edd@syzkaller.appspotmail.com
Reported-by: syzbot+9d2abfef257f3e2d4713@syzkaller.appspotmail.com
Suggested-by: Hillf Danton <hdanton@sina.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200804185815.2453-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
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>
while to come. Changes include:
- Some new Chinese translations
- Progress on the battle against double words words and non-HTTPS URLs
- Some block-mq documentation
- More RST conversions from Mauro. At this point, that task is
essentially complete, so we shouldn't see this kind of churn again for a
while. Unless we decide to switch to asciidoc or something...:)
- Lots of typo fixes, warning fixes, and more.
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Merge tag 'docs-5.9' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
"It's been a busy cycle for documentation - hopefully the busiest for a
while to come. Changes include:
- Some new Chinese translations
- Progress on the battle against double words words and non-HTTPS
URLs
- Some block-mq documentation
- More RST conversions from Mauro. At this point, that task is
essentially complete, so we shouldn't see this kind of churn again
for a while. Unless we decide to switch to asciidoc or
something...:)
- Lots of typo fixes, warning fixes, and more"
* tag 'docs-5.9' of git://git.lwn.net/linux: (195 commits)
scripts/kernel-doc: optionally treat warnings as errors
docs: ia64: correct typo
mailmap: add entry for <alobakin@marvell.com>
doc/zh_CN: add cpu-load Chinese version
Documentation/admin-guide: tainted-kernels: fix spelling mistake
MAINTAINERS: adjust kprobes.rst entry to new location
devices.txt: document rfkill allocation
PCI: correct flag name
docs: filesystems: vfs: correct flag name
docs: filesystems: vfs: correct sync_mode flag names
docs: path-lookup: markup fixes for emphasis
docs: path-lookup: more markup fixes
docs: path-lookup: fix HTML entity mojibake
CREDITS: Replace HTTP links with HTTPS ones
docs: process: Add an example for creating a fixes tag
doc/zh_CN: add Chinese translation prefer section
doc/zh_CN: add clearing-warn-once Chinese version
doc/zh_CN: add admin-guide index
doc:it_IT: process: coding-style.rst: Correct __maybe_unused compiler label
futex: MAINTAINERS: Re-add selftests directory
...
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Merge tag 'printk-for-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux
Pull printk updates from Petr Mladek:
- Herbert Xu made printk header file self-contained.
- Andy Shevchenko and Sergey Senozhatsky cleaned up console->setup()
error handling.
- Andy Shevchenko did some cleanups (e.g. sparse warning) in vsprintf
code.
- Minor documentation updates.
* tag 'printk-for-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
lib/vsprintf: Force type of flags value for gfp_t
lib/vsprintf: Replace custom spec to print decimals with generic one
lib/vsprintf: Replace hidden BUILD_BUG_ON() with static_assert()
printk: Make linux/printk.h self-contained
doc:kmsg: explicitly state the return value in case of SEEK_CUR
Replace HTTP links with HTTPS ones: vsprintf
hvc: unify console setup naming
console: Fix trivia typo 'change' -> 'chance'
console: Propagate error code from console ->setup()
tty: hvc: Return proper error code from console ->setup() hook
serial: sunzilog: Return proper error code from console ->setup() hook
serial: sunsab: Return proper error code from console ->setup() hook
mips: Return proper error code from console ->setup() hook
Pull parisc updates from Helge Deller:
"The majority of the patches are reverts of previous commits regarding
the parisc-specific low level spinlocking code and barrier handling,
with which we tried to fix CPU stalls on our build servers. In the end
John David Anglin found the culprit: We missed a define for
atomic64_set_release(). This seems to have fixed our issues, so now
it's good to remove the unnecessary code again.
Other than that it's trivial stuff: Spelling fixes, constifications
and such"
* 'parisc-5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: make the log level string for register dumps const
parisc: Do not use an ordered store in pa_tlb_lock()
Revert "parisc: Revert "Release spinlocks using ordered store""
Revert "parisc: Use ldcw instruction for SMP spinlock release barrier"
Revert "parisc: Drop LDCW barrier in CAS code when running UP"
Revert "parisc: Improve interrupt handling in arch_spin_lock_flags()"
parisc: Replace HTTP links with HTTPS ones
parisc: elf.h: delete a duplicated word
parisc: Report bad pages as HardwareCorrupted
parisc: Convert to BIT_MASK() and BIT_WORD()
this has been brought into a shape which is maintainable and actually
works.
This final version was done by Sasha Levin who took it up after Intel
dropped the ball. Sasha discovered that the SGX (sic!) offerings out there
ship rogue kernel modules enabling FSGSBASE behind the kernels back which
opens an instantanious unpriviledged root hole.
The FSGSBASE instructions provide a considerable speedup of the context
switch path and enable user space to write GSBASE without kernel
interaction. This enablement requires careful handling of the exception
entries which go through the paranoid entry path as they cannot longer rely
on the assumption that user GSBASE is positive (as enforced via prctl() on
non FSGSBASE enabled systemn). All other entries (syscalls, interrupts and
exceptions) can still just utilize SWAPGS unconditionally when the entry
comes from user space. Converting these entries to use FSGSBASE has no
benefit as SWAPGS is only marginally slower than WRGSBASE and locating and
retrieving the kernel GSBASE value is not a free operation either. The real
benefit of RD/WRGSBASE is the avoidance of the MSR reads and writes.
The changes come with appropriate selftests and have held up in field
testing against the (sanitized) Graphene-SGX driver.
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Merge tag 'x86-fsgsbase-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fsgsbase from Thomas Gleixner:
"Support for FSGSBASE. Almost 5 years after the first RFC to support
it, this has been brought into a shape which is maintainable and
actually works.
This final version was done by Sasha Levin who took it up after Intel
dropped the ball. Sasha discovered that the SGX (sic!) offerings out
there ship rogue kernel modules enabling FSGSBASE behind the kernels
back which opens an instantanious unpriviledged root hole.
The FSGSBASE instructions provide a considerable speedup of the
context switch path and enable user space to write GSBASE without
kernel interaction. This enablement requires careful handling of the
exception entries which go through the paranoid entry path as they
can no longer rely on the assumption that user GSBASE is positive (as
enforced via prctl() on non FSGSBASE enabled systemn).
All other entries (syscalls, interrupts and exceptions) can still just
utilize SWAPGS unconditionally when the entry comes from user space.
Converting these entries to use FSGSBASE has no benefit as SWAPGS is
only marginally slower than WRGSBASE and locating and retrieving the
kernel GSBASE value is not a free operation either. The real benefit
of RD/WRGSBASE is the avoidance of the MSR reads and writes.
The changes come with appropriate selftests and have held up in field
testing against the (sanitized) Graphene-SGX driver"
* tag 'x86-fsgsbase-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits)
x86/fsgsbase: Fix Xen PV support
x86/ptrace: Fix 32-bit PTRACE_SETREGS vs fsbase and gsbase
selftests/x86/fsgsbase: Add a missing memory constraint
selftests/x86/fsgsbase: Fix a comment in the ptrace_write_gsbase test
selftests/x86: Add a syscall_arg_fault_64 test for negative GSBASE
selftests/x86/fsgsbase: Test ptracer-induced GS base write with FSGSBASE
selftests/x86/fsgsbase: Test GS selector on ptracer-induced GS base write
Documentation/x86/64: Add documentation for GS/FS addressing mode
x86/elf: Enumerate kernel FSGSBASE capability in AT_HWCAP2
x86/cpu: Enable FSGSBASE on 64bit by default and add a chicken bit
x86/entry/64: Handle FSGSBASE enabled paranoid entry/exit
x86/entry/64: Introduce the FIND_PERCPU_BASE macro
x86/entry/64: Switch CR3 before SWAPGS in paranoid entry
x86/speculation/swapgs: Check FSGSBASE in enabling SWAPGS mitigation
x86/process/64: Use FSGSBASE instructions on thread copy and ptrace
x86/process/64: Use FSBSBASE in switch_to() if available
x86/process/64: Make save_fsgs_for_kvm() ready for FSGSBASE
x86/fsgsbase/64: Enable FSGSBASE instructions in helper functions
x86/fsgsbase/64: Add intrinsics for FSGSBASE instructions
x86/cpu: Add 'unsafe_fsgsbase' to enable CR4.FSGSBASE
...
Michael S. Tsirkin