Starting from ICL, the default for MIPI GPIO sequences seems to be using
native GPIOs i.e. GPIOs available in the GPU. These native GPIOs reuse
many pins that quite frankly seem scary to poke based on the VBT
sequences. We pretty much have to trust that the board is configured
such that the relevant HPD, PP_CONTROL and GPIO bits aren't used for
anything else.
MIPI sequence v4 also adds a flag to fall back to non-native sequences.
v5:
- Wrap SHOTPLUG_CTL_DDI modification in spin_lock() in icp_irq_handler()
too (Ville)
- References instead of Closes issue 6131 because this does not fix everything
v4:
- Wrap SHOTPLUG_CTL_DDI modification in spin_lock_irq() (Ville)
v3:
- Fix -Wbitwise-conditional-parentheses (kernel test robot <lkp@intel.com>)
v2:
- Fix HPD pin output set (impacts GPIOs 0 and 5)
- Fix GPIO data output direction set (impacts GPIOs 4 and 9)
- Reduce register accesses to single intel_de_rwm()
References: https://gitlab.freedesktop.org/drm/intel/-/issues/6131
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221219105955.4014451-1-jani.nikula@intel.com
Pull VFIO updates from Alex Williamson:
- Replace deprecated git://github.com link in MAINTAINERS (Palmer
Dabbelt)
- Simplify vfio/mlx5 with module_pci_driver() helper (Shang XiaoJing)
- Drop unnecessary buffer from ACPI call (Rafael Mendonca)
- Correct latent missing include issue in iova-bitmap and fix support
for unaligned bitmaps. Follow-up with better fix through refactor
(Joao Martins)
- Rework ccw mdev driver to split private data from parent structure,
better aligning with the mdev lifecycle and allowing us to remove a
temporary workaround (Eric Farman)
- Add an interface to get an estimated migration data size for a
device, allowing userspace to make informed decisions, ex. more
accurately predicting VM downtime (Yishai Hadas)
- Fix minor typo in vfio/mlx5 array declaration (Yishai Hadas)
- Simplify module and Kconfig through consolidating SPAPR/EEH code and
config options and folding virqfd module into main vfio module (Jason
Gunthorpe)
- Fix error path from device_register() across all vfio mdev and sample
drivers (Alex Williamson)
- Define migration pre-copy interface and implement for vfio/mlx5
devices, allowing portions of the device state to be saved while the
device continues operation, towards reducing the stop-copy state size
(Jason Gunthorpe, Yishai Hadas, Shay Drory)
- Implement pre-copy for hisi_acc devices (Shameer Kolothum)
- Fixes to mdpy mdev driver remove path and error path on probe (Shang
XiaoJing)
- vfio/mlx5 fixes for incorrect return after copy_to_user() fault and
incorrect buffer freeing (Dan Carpenter)
* tag 'vfio-v6.2-rc1' of https://github.com/awilliam/linux-vfio: (42 commits)
vfio/mlx5: error pointer dereference in error handling
vfio/mlx5: fix error code in mlx5vf_precopy_ioctl()
samples: vfio-mdev: Fix missing pci_disable_device() in mdpy_fb_probe()
hisi_acc_vfio_pci: Enable PRE_COPY flag
hisi_acc_vfio_pci: Move the dev compatibility tests for early check
hisi_acc_vfio_pci: Introduce support for PRE_COPY state transitions
hisi_acc_vfio_pci: Add support for precopy IOCTL
vfio/mlx5: Enable MIGRATION_PRE_COPY flag
vfio/mlx5: Fallback to STOP_COPY upon specific PRE_COPY error
vfio/mlx5: Introduce multiple loads
vfio/mlx5: Consider temporary end of stream as part of PRE_COPY
vfio/mlx5: Introduce vfio precopy ioctl implementation
vfio/mlx5: Introduce SW headers for migration states
vfio/mlx5: Introduce device transitions of PRE_COPY
vfio/mlx5: Refactor to use queue based data chunks
vfio/mlx5: Refactor migration file state
vfio/mlx5: Refactor MKEY usage
vfio/mlx5: Refactor PD usage
vfio/mlx5: Enforce a single SAVE command at a time
vfio: Extend the device migration protocol with PRE_COPY
...
Pull kernel hardening updates from Kees Cook:
- Convert flexible array members, fix -Wstringop-overflow warnings, and
fix KCFI function type mismatches that went ignored by maintainers
(Gustavo A. R. Silva, Nathan Chancellor, Kees Cook)
- Remove the remaining side-effect users of ksize() by converting
dma-buf, btrfs, and coredump to using kmalloc_size_roundup(), add
more __alloc_size attributes, and introduce full testing of all
allocator functions. Finally remove the ksize() side-effect so that
each allocation-aware checker can finally behave without exceptions
- Introduce oops_limit (default 10,000) and warn_limit (default off) to
provide greater granularity of control for panic_on_oops and
panic_on_warn (Jann Horn, Kees Cook)
- Introduce overflows_type() and castable_to_type() helpers for cleaner
overflow checking
- Improve code generation for strscpy() and update str*() kern-doc
- Convert strscpy and sigphash tests to KUnit, and expand memcpy tests
- Always use a non-NULL argument for prepare_kernel_cred()
- Disable structleak plugin in FORTIFY KUnit test (Anders Roxell)
- Adjust orphan linker section checking to respect CONFIG_WERROR (Xin
Li)
- Make sure siginfo is cleared for forced SIGKILL (haifeng.xu)
- Fix um vs FORTIFY warnings for always-NULL arguments
* tag 'hardening-v6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (31 commits)
ksmbd: replace one-element arrays with flexible-array members
hpet: Replace one-element array with flexible-array member
um: virt-pci: Avoid GCC non-NULL warning
signal: Initialize the info in ksignal
lib: fortify_kunit: build without structleak plugin
panic: Expose "warn_count" to sysfs
panic: Introduce warn_limit
panic: Consolidate open-coded panic_on_warn checks
exit: Allow oops_limit to be disabled
exit: Expose "oops_count" to sysfs
exit: Put an upper limit on how often we can oops
panic: Separate sysctl logic from CONFIG_SMP
mm/pgtable: Fix multiple -Wstringop-overflow warnings
mm: Make ksize() a reporting-only function
kunit/fortify: Validate __alloc_size attribute results
drm/sti: Fix return type of sti_{dvo,hda,hdmi}_connector_mode_valid()
drm/fsl-dcu: Fix return type of fsl_dcu_drm_connector_mode_valid()
driver core: Add __alloc_size hint to devm allocators
overflow: Introduce overflows_type() and castable_to_type()
coredump: Proactively round up to kmalloc bucket size
...
Pull iommufd implementation from Jason Gunthorpe:
"iommufd is the user API to control the IOMMU subsystem as it relates
to managing IO page tables that point at user space memory.
It takes over from drivers/vfio/vfio_iommu_type1.c (aka the VFIO
container) which is the VFIO specific interface for a similar idea.
We see a broad need for extended features, some being highly IOMMU
device specific:
- Binding iommu_domain's to PASID/SSID
- Userspace IO page tables, for ARM, x86 and S390
- Kernel bypassed invalidation of user page tables
- Re-use of the KVM page table in the IOMMU
- Dirty page tracking in the IOMMU
- Runtime Increase/Decrease of IOPTE size
- PRI support with faults resolved in userspace
Many of these HW features exist to support VM use cases - for instance
the combination of PASID, PRI and Userspace IO Page Tables allows an
implementation of DMA Shared Virtual Addressing (vSVA) within a guest.
Dirty tracking enables VM live migration with SRIOV devices and PASID
support allow creating "scalable IOV" devices, among other things.
As these features are fundamental to a VM platform they need to be
uniformly exposed to all the driver families that do DMA into VMs,
which is currently VFIO and VDPA"
For more background, see the extended explanations in Jason's pull request:
https://lore.kernel.org/lkml/Y5dzTU8dlmXTbzoJ@nvidia.com/
* tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd: (62 commits)
iommufd: Change the order of MSI setup
iommufd: Improve a few unclear bits of code
iommufd: Fix comment typos
vfio: Move vfio group specific code into group.c
vfio: Refactor dma APIs for emulated devices
vfio: Wrap vfio group module init/clean code into helpers
vfio: Refactor vfio_device open and close
vfio: Make vfio_device_open() truly device specific
vfio: Swap order of vfio_device_container_register() and open_device()
vfio: Set device->group in helper function
vfio: Create wrappers for group register/unregister
vfio: Move the sanity check of the group to vfio_create_group()
vfio: Simplify vfio_create_group()
iommufd: Allow iommufd to supply /dev/vfio/vfio
vfio: Make vfio_container optionally compiled
vfio: Move container related MODULE_ALIAS statements into container.c
vfio-iommufd: Support iommufd for emulated VFIO devices
vfio-iommufd: Support iommufd for physical VFIO devices
vfio-iommufd: Allow iommufd to be used in place of a container fd
vfio: Use IOMMU_CAP_ENFORCE_CACHE_COHERENCY for vfio_file_enforced_coherent()
...
It seems we can have one or more framebuffers that are still pinned when
suspending lmem, in such a case we end up creating a shmem backup
object, instead of evicting the object directly, but this will skip
copying the CCS aux state, since we don't allocate the extra storage for
the CCS pages as part of the ttm_tt construction. Since we can already
deal with pinned objects just fine, it doesn't seem too nasty to just
extend to support dealing with the CCS aux state, if the object is a
pinned framebuffer. This fixes display corruption (like in gnome-shell)
seen on DG2 when returning from suspend.
Fixes: da0595ae91 ("drm/i915/migrate: Evict and restore the flatccs capable lmem obj")
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Nirmoy Das <nirmoy.das@intel.com>
Cc: Andrzej Hajda <andrzej.hajda@intel.com>
Cc: Shuicheng Lin <shuicheng.lin@intel.com>
Cc: <stable@vger.kernel.org> # v5.19+
Tested-by: Nirmoy Das <nirmoy.das@intel.com>
Reviewed-by: Nirmoy Das <nirmoy.das@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221212171958.82593-2-matthew.auld@intel.com
Pull drm updates from Dave Airlie:
"The biggest highlight is that the accel subsystem framework is merged.
Hopefully for 6.3 we will be able to line up a driver to use it.
In drivers land, i915 enables DG2 support by default now, and nouveau
has a big stability refactoring and initial ampere support, AMD
includes new hw IP support and should build on ARM again. There is
also an ofdrm driver to take over offb on platforms it's used.
Stuff outside my tree, the dma-buf patches hit a few places, the vc4
firmware changes also do, and i915 has some interactions with MEI for
discrete GPUs. I think all of those should have been acked/reviewed by
relevant parties.
New driver:
- ofdrm - replacement for offb
fbdev:
- add support for nomodeset
fourcc:
- add Vivante tiled modifier
core:
- atomic-helpers: CRTC primary plane test fixes, fb access hooks
- connector: TV API consistency, cmdline parser improvements
- send connector hotplug on cleanup
- sort makefile objects
tests:
- sort kunit tests
- improve DP-MST tests
- add kunit helpers to create a device
sched:
- module param for scheduling policy
- refcounting fix
buddy:
- add back random seed log
ttm:
- convert ttm_resource to size_t
- optimize pool allocations
edid:
- HFVSDB parsing support fixes
- logging/debug improvements
- DSC quirks
dma-buf:
- Add unlocked vmap and attachment mapping
- move drivers to common locking convention
- locking improvements
firmware:
- new API for rPI firmware and vc4
xilinx:
- zynqmp: displayport bridge support
- dpsub fix
bridge:
- adv7533: Remove dynamic lane switching
- it6505: Runtime PM support, sync improvements
- ps8640: Handle AUX defer messages
- tc358775: Drop soft-reset over I2C
panel:
- panel-edp: Add INX N116BGE-EA2 C2 and C4 support.
- Jadard JD9365DA-H3
- NewVision NV3051D
amdgpu:
- DCN support on ARM
- DCN 2.1 secure display
- Sienna Cichlid mode2 reset fixes
- new GC 11.x firmware versions
- drop AMD specific DSC workarounds in favour of drm code
- clang warning fixes
- scheduler rework
- SR-IOV fixes
- GPUVM locking fixes
- fix memory leak in CS IOCTL error path
- flexible array updates
- enable new GC/PSP/SMU/NBIO IP
- GFX preemption support for gfx9
amdkfd:
- cache size fixes
- userptr fixes
- enable cooperative launch on gfx 10.3
- enable GC 11.0.4 KFD support
radeon:
- replace kmap with kmap_local_page
- ACPI ref count fix
- HDA audio notifier support
i915:
- DG2 enabled by default
- MTL enablement work
- hotplug refactoring
- VBT improvements
- Display and watermark refactoring
- ADL-P workaround
- temp disable runtime_pm for discrete-
- fix for A380 as a secondary GPU
- Wa_18017747507 for DG2
- CS timestamp support fixes for gen5 and earlier
- never purge busy TTM objects
- use i915_sg_dma_sizes for all backends
- demote GuC kernel contexts to normal priority
- gvt: refactor for new MDEV interface
- enable DC power states on eDP ports
- fix gen 2/3 workarounds
nouveau:
- fix page fault handling
- Ampere acceleration support
- driver stability improvements
- nva3 backlight support
msm:
- MSM_INFO_GET_FLAGS support
- DPU: XR30 and P010 image formats
- Qualcomm SM6115 support
- DSI PHY support for QCM2290
- HDMI: refactored dev init path
- remove exclusive-fence hack
- fix speed-bin detection
- enable clamp to idle on 7c3
- improved hangcheck detection
vmwgfx:
- fb and cursor refactoring
- convert to generic hashtable
- cursor improvements
etnaviv:
- hw workarounds
- softpin MMU fixes
ast:
- atomic gamma LUT support
- convert to SHMEM
lcdif:
- support YUV planes
- Increase DMA burst size
- FIFO threshold tuning
meson:
- fix return type of cvbs mode_valid
mgag200:
- fix PLL setup on some revisions
sun4i:
- A100 and D1 support
udl:
- modesetting improvements
- hot unplug support
vc4:
- support PAL-M
- fix regression preventing 4K @ 60Hz
- fix NULL ptr deref
v3d:
- switch to drm managed resources
renesas:
- RZ/G2L DSI support
- DU Kconfig cleanup
mediatek:
- fixup dpi and hdmi
- MT8188 dpi support
- MT8195 AFBC support
tegra:
- NVDEC hardware on Tegra234 SoC
hdlcd:
- switch to drm managed resources
ingenic:
- fix registration error path
hisilicon:
- convert to drm_mode_init
maildp:
- use managed resources
mtk:
- use drm_mode_init
rockchip:
- use drm_mode_copy"
* tag 'drm-next-2022-12-13' of git://anongit.freedesktop.org/drm/drm: (1397 commits)
drm/amdgpu: fix mmhub register base coding error
drm/amdgpu: add tmz support for GC IP v11.0.4
drm/amdgpu: enable GFX Clock Gating control for GC IP v11.0.4
drm/amdgpu: enable GFX Power Gating for GC IP v11.0.4
drm/amdgpu: enable GFX IP v11.0.4 CG support
drm/amdgpu: Make amdgpu_ring_mux functions as static
drm/amdgpu: generally allow over-commit during BO allocation
drm/amd/display: fix array index out of bound error in DCN32 DML
drm/amd/display: 3.2.215
drm/amd/display: set optimized required for comp buf changes
drm/amd/display: Add debug option to skip PSR CRTC disable
drm/amd/display: correct DML calc error of UrgentLatency
drm/amd/display: correct static_screen_event_mask
drm/amd/display: Ensure commit_streams returns the DC return code
drm/amd/display: read invalid ddc pin status cause engine busy
drm/amd/display: Bypass DET swath fill check for max clocks
drm/amd/display: Disable uclk pstate for subvp pipes
drm/amd/display: Fix DCN2.1 default DSC clocks
drm/amd/display: Enable dp_hdmi21_pcon support
drm/amd/display: prevent seamless boot on displays that don't have the preferred dig
...
Fix intel_dp_dsc_compute_config, previously timeslots parameter
was used in fact not as a timeslots, but more like a ratio
timeslots/64, which of course didn't have any effect for SST DSC,
but causes now issues for MST DSC.
Secondly we need to calculate pipe_bpp using intel_dp_dsc_compute_bpp
only for SST DSC case, while for MST case it has been calculated
earlier already with intel_dp_dsc_mst_compute_link_config.
Third we also were wrongly determining sink min bpp/max bpp, those
limites should be intersected with our limits to find common
acceptable bpp's, plus on top of that we should align those with
VESA bpps and only then calculate required timeslots amount.
Some MST hubs started to work only after third change was made.
v2: Make kernel test robot happy(claimed there was unitialzed use,
while there is none)
v3: Rename intel_dp_dsc_nearest_vesa_bpp to intel_dp_dsc_nearest_valid_bpp
(Manasi Navare)
Reviewed-by: Manasi Navare <manasi.d.navare@intel.com>
Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221123100718.29130-1-stanislav.lisovskiy@intel.com
We might to use that function separately from intel_dp_dsc_compute_config
for DP DSC over MST case, because allocating bandwidth in that
case can be a bit more tricky. So in order to avoid code copy-pasta
lets extract this to separate function and reuse it for both SST
and MST cases.
v2: Removed multiple blank lines
v3: Rename intel_dp_dsc_nearest_vesa_bpp to intel_dp_dsc_nearest_valid_bpp
to reflect its meaning more properly.
(Manasi Navare)
Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Reviewed-by: Manasi Navare <manasi.d.navare@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221123100551.29080-1-stanislav.lisovskiy@intel.com
Whenever we are not able to get enough timeslots
for required PBN, let's try to allocate those
using DSC, just same way as we do for SST.
v2: Removed intel_dp_mst_dsc_compute_config and refactored
intel_dp_dsc_compute_config to support timeslots as a
parameter(Ville Syrjälä)
v3: - Rebased
- Added a debug to see that we at least try reserving
VCPI slots using DSC, because currently its not visible
from the logs, thus making debugging more tricky.
- Moved timeslots to numerator, where it should be.
v4: - Call drm_dp_mst_atomic_check already during link
config computation, because we need to know already
by this moment if uncompressed amount of VCPI slots
needed can fit, otherwise we need to use DSC.
(thanks to Vinod Govindapillai for pointing this out)
v5: - Put pipe_config->bigjoiner_pipes back to original
condition in intel_dp_dsc_compute_config
(don't remember when I lost it)
v6: - Removed unnecessary drm_dp_mst_atomic_check as it is
now always called in a newly introduced
intel_dp_mst_find_vcpi_slots_for_bpp function
(Vinod Govindapillai)
Reviewed-by: Vinod Govindapillai <vinod.govindapillai@intel.com>
Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221101094222.22091-5-stanislav.lisovskiy@intel.com
We currently always exit that bpp loop because
drm_dp_atomic_find_vcpi_slots doesn't care if we actually
can fit those or not.
I think that wasn't the initial intention here, especially when
we keep trying with lower bpps, we are supposed to keep trying
until we actually find some _working_ configuration, which isn't the
case here.
So added that drm_dp_mst_check here, so that we can make sure
that try all the bpps before we fail.
Reviewed-by: Vinod Govindapillai <vinod.govindapillai@intel.com>
Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221101094222.22091-3-stanislav.lisovskiy@intel.com
We could use the dsb to load the LUT in any gamma mode, not just
when using the multi-segment mode. So replace the direct mmio
on all ilk+ paths with the wrapper.
There are a few functions (ilk_load_lut_10(), ivb_load_lut_10())
that would never be used on a platform with dsb so we could
skip those, but probably better to keep all this 100% consistent
to avoid people getting confused and copy pasting the wrong thing
when adding a new gamma mode.
The gmch stuff I left with direct mmio since those are fairly
distinct and shouldn't cause too much confusion. Although
I've also pondered about converting everything over to dsb
command buffers and just executing it on the CPU when the
real hw is not available. But dunno if that would actually
be a good idea or not...
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221123152638.20622-13-ville.syrjala@linux.intel.com
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
The DSB has problem loading the LUTs at the moment. Some
of that is due to the palette anti collision logic, some
due to what seem real hw issues. Disable it the whole
thing locally in the color management code for now.
Note that we currently have this weird situation where on
adl+ we load parts of the LUT with DSB and parts with mmio.
That is due to the fact that only some parts of the LUT code
are using the DSB register write functions (ivb_load_lut_ext*()),
while the rest is using pure mmio (bdw_load_lut_10()). So now
we'll go back to pure mmio temporarily, until the DSB issues
get fixed (at which point we should be going for pure DSB).
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221123152638.20622-11-ville.syrjala@linux.intel.com
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Since the color management code is the only user of the DSB
at the moment move the DSB prepare/cleanup there too. The
code has to anyway make decisions on whether to use the DSB
or not (and how to use it). Also we'll need a place where we
actually generate the DSB command buffer ahead of time rather
than the current situation where it gets generated too late
during the mmio programming of the hardware.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221123152638.20622-9-ville.syrjala@linux.intel.com
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Various gamma units on various platforms have some problems loading
the LUT index and auto-increment bit at the same time. We have to
do this in two steps. The first known case was the glk degamma LUT,
but at least ADL has another known case.
We're not going to suffer too badly from a couple of extra register
writes here, so let's just standardize on this practice for all
auto-increment LUT loads/reads. This way we never have to worry about
this specific issue again. And for good measure always reset the
index back to zero at the end (we already did this in a few places).
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221123152638.20622-6-ville.syrjala@linux.intel.com
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Pull random number generator updates from Jason Donenfeld:
- Replace prandom_u32_max() and various open-coded variants of it,
there is now a new family of functions that uses fast rejection
sampling to choose properly uniformly random numbers within an
interval:
get_random_u32_below(ceil) - [0, ceil)
get_random_u32_above(floor) - (floor, U32_MAX]
get_random_u32_inclusive(floor, ceil) - [floor, ceil]
Coccinelle was used to convert all current users of
prandom_u32_max(), as well as many open-coded patterns, resulting in
improvements throughout the tree.
I'll have a "late" 6.1-rc1 pull for you that removes the now unused
prandom_u32_max() function, just in case any other trees add a new
use case of it that needs to converted. According to linux-next,
there may be two trivial cases of prandom_u32_max() reintroductions
that are fixable with a 's/.../.../'. So I'll have for you a final
conversion patch doing that alongside the removal patch during the
second week.
This is a treewide change that touches many files throughout.
- More consistent use of get_random_canary().
- Updates to comments, documentation, tests, headers, and
simplification in configuration.
- The arch_get_random*_early() abstraction was only used by arm64 and
wasn't entirely useful, so this has been replaced by code that works
in all relevant contexts.
- The kernel will use and manage random seeds in non-volatile EFI
variables, refreshing a variable with a fresh seed when the RNG is
initialized. The RNG GUID namespace is then hidden from efivarfs to
prevent accidental leakage.
These changes are split into random.c infrastructure code used in the
EFI subsystem, in this pull request, and related support inside of
EFISTUB, in Ard's EFI tree. These are co-dependent for full
functionality, but the order of merging doesn't matter.
- Part of the infrastructure added for the EFI support is also used for
an improvement to the way vsprintf initializes its siphash key,
replacing an sleep loop wart.
- The hardware RNG framework now always calls its correct random.c
input function, add_hwgenerator_randomness(), rather than sometimes
going through helpers better suited for other cases.
- The add_latent_entropy() function has long been called from the fork
handler, but is a no-op when the latent entropy gcc plugin isn't
used, which is fine for the purposes of latent entropy.
But it was missing out on the cycle counter that was also being mixed
in beside the latent entropy variable. So now, if the latent entropy
gcc plugin isn't enabled, add_latent_entropy() will expand to a call
to add_device_randomness(NULL, 0), which adds a cycle counter,
without the absent latent entropy variable.
- The RNG is now reseeded from a delayed worker, rather than on demand
when used. Always running from a worker allows it to make use of the
CPU RNG on platforms like S390x, whose instructions are too slow to
do so from interrupts. It also has the effect of adding in new inputs
more frequently with more regularity, amounting to a long term
transcript of random values. Plus, it helps a bit with the upcoming
vDSO implementation (which isn't yet ready for 6.2).
- The jitter entropy algorithm now tries to execute on many different
CPUs, round-robining, in hopes of hitting even more memory latencies
and other unpredictable effects. It also will mix in a cycle counter
when the entropy timer fires, in addition to being mixed in from the
main loop, to account more explicitly for fluctuations in that timer
firing. And the state it touches is now kept within the same cache
line, so that it's assured that the different execution contexts will
cause latencies.
* tag 'random-6.2-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random: (23 commits)
random: include <linux/once.h> in the right header
random: align entropy_timer_state to cache line
random: mix in cycle counter when jitter timer fires
random: spread out jitter callback to different CPUs
random: remove extraneous period and add a missing one in comments
efi: random: refresh non-volatile random seed when RNG is initialized
vsprintf: initialize siphash key using notifier
random: add back async readiness notifier
random: reseed in delayed work rather than on-demand
random: always mix cycle counter in add_latent_entropy()
hw_random: use add_hwgenerator_randomness() for early entropy
random: modernize documentation comment on get_random_bytes()
random: adjust comment to account for removed function
random: remove early archrandom abstraction
random: use random.trust_{bootloader,cpu} command line option only
stackprotector: actually use get_random_canary()
stackprotector: move get_random_canary() into stackprotector.h
treewide: use get_random_u32_inclusive() when possible
treewide: use get_random_u32_{above,below}() instead of manual loop
treewide: use get_random_u32_below() instead of deprecated function
...
Instead of defining two versions of intel_sysfs_rc6_init(), one for each
value of CONFIG_PM, add a check on !IS_ENABLED(CONFIG_PM) early in the
function. This will allow the compiler to automatically drop the dead
code when CONFIG_PM is disabled, without having to use #ifdef guards.
This has the advantage of always compiling these functions in,
independently of any Kconfig option. Thanks to that, bugs and other
regressions are subsequently easier to catch.
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221129191942.138244-13-paul@crapouillou.net
