commit f8e6343b7a upstream.
Resolves the following lockdep report when booting PREEMPT_RT on Hyper-V
with related guest support enabled:
[ 1.127941] hv_vmbus: registering driver hyperv_drm
[ 1.132518] =============================
[ 1.132519] [ BUG: Invalid wait context ]
[ 1.132521] 6.19.0-rc8+ #9 Not tainted
[ 1.132524] -----------------------------
[ 1.132525] swapper/0/0 is trying to lock:
[ 1.132526] ffff8b9381bb3c90 (&channel->sched_lock){....}-{3:3}, at: vmbus_chan_sched+0xc4/0x2b0
[ 1.132543] other info that might help us debug this:
[ 1.132544] context-{2:2}
[ 1.132545] 1 lock held by swapper/0/0:
[ 1.132547] #0: ffffffffa010c4c0 (rcu_read_lock){....}-{1:3}, at: vmbus_chan_sched+0x31/0x2b0
[ 1.132557] stack backtrace:
[ 1.132560] CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.19.0-rc8+ #9 PREEMPT_{RT,(lazy)}
[ 1.132565] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 09/25/2025
[ 1.132567] Call Trace:
[ 1.132570] <IRQ>
[ 1.132573] dump_stack_lvl+0x6e/0xa0
[ 1.132581] __lock_acquire+0xee0/0x21b0
[ 1.132592] lock_acquire+0xd5/0x2d0
[ 1.132598] ? vmbus_chan_sched+0xc4/0x2b0
[ 1.132606] ? lock_acquire+0xd5/0x2d0
[ 1.132613] ? vmbus_chan_sched+0x31/0x2b0
[ 1.132619] rt_spin_lock+0x3f/0x1f0
[ 1.132623] ? vmbus_chan_sched+0xc4/0x2b0
[ 1.132629] ? vmbus_chan_sched+0x31/0x2b0
[ 1.132634] vmbus_chan_sched+0xc4/0x2b0
[ 1.132641] vmbus_isr+0x2c/0x150
[ 1.132648] __sysvec_hyperv_callback+0x5f/0xa0
[ 1.132654] sysvec_hyperv_callback+0x88/0xb0
[ 1.132658] </IRQ>
[ 1.132659] <TASK>
[ 1.132660] asm_sysvec_hyperv_callback+0x1a/0x20
As code paths that handle vmbus IRQs use sleepy locks under PREEMPT_RT,
the vmbus_isr execution needs to be moved into thread context. Open-
coding this allows to skip the IPI that irq_work would additionally
bring and which we do not need, being an IRQ, never an NMI.
This affects both x86 and arm64, therefore hook into the common driver
logic.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Florian Bezdeka <florian.bezdeka@siemens.com>
Tested-by: Florian Bezdeka <florian.bezdeka@siemens.com>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 49f49d47af ]
hv_kmsg_dump() currently skips the panic notification entirely if it
doesn't get any message bytes to pass to Hyper-V due to an error from
kmsg_dump_get_buffer(). Skipping the notification is undesirable because
it leaves the Hyper-V host uncertain about the state of a panic'ed guest.
Fix this by always doing the panic notification, even if bytes_written
is zero. Also ensure that bytes_written is initialized, which fixes a
kernel test robot warning. The warning is actually bogus because
kmsg_dump_get_buffer() happens to set bytes_written even if it fails, and
in the kernel test robot's CONFIG_PRINTK not set case, hv_kmsg_dump() is
never called. But do the initialization for robustness and to quiet the
static checker.
Fixes: 9c318a1d9b ("Drivers: hv: move panic report code from vmbus to hv early init code")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/all/202512172103.OcUspn1Z-lkp@intel.com/
Signed-off-by: Michael Kelley <mhklinux@outlook.com>
Reviewed-by: Roman Kisel <vdso@mailbox.org>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 65995e97a1 upstream.
The ring buffer size varies across VMBus channels. The size of sysfs
node for the ring buffer is currently hardcoded to 4 MB. Userspace
clients either use fstat() or hardcode this size for doing mmap().
To address this, make the sysfs node size dynamic to reflect the
actual ring buffer size for each channel. This will ensure that
fstat() on ring sysfs node always returns the correct size of
ring buffer.
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Reviewed-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Naman Jain <namjain@linux.microsoft.com>
Link: https://lore.kernel.org/r/20250502074811.2022-3-namjain@linux.microsoft.com
[ The structure "struct attribute_group" does not have bin_size field in
v6.12.x kernel so the logic of configuring size of sysfs node for ring buffer
has been moved to vmbus_chan_bin_attr_is_visible().
Original change was not a fix, but it needs to be backported to fix size
related discrepancy caused by the commit mentioned in Fixes tag. ]
Signed-off-by: Naman Jain <namjain@linux.microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 380b75d307 upstream.
vmbus_sendpacket_mpb_desc() is currently used only by the storvsc driver
and is hardcoded to create a single GPA range. To allow it to also be
used by the netvsc driver to create multiple GPA ranges, no longer
hardcode as having a single GPA range. Allow the calling driver to
specify the rangecount in the supplied descriptor.
Update the storvsc driver to reflect this new approach.
Cc: <stable@vger.kernel.org> # 6.1.x
Signed-off-by: Michael Kelley <mhklinux@outlook.com>
Link: https://patch.msgid.link/20250513000604.1396-2-mhklinux@outlook.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit f31fe8165d ]
On regular bootup, devices get registered to VMBus first, so when
uio_hv_generic driver for a particular device type is probed,
the device is already initialized and added, so sysfs creation in
hv_uio_probe() works fine. However, when the device is removed
and brought back, the channel gets rescinded and the device again gets
registered to VMBus. However this time, the uio_hv_generic driver is
already registered to probe for that device and in this case sysfs
creation is tried before the device's kobject gets initialized
completely.
Fix this by moving the core logic of sysfs creation of ring buffer,
from uio_hv_generic to HyperV's VMBus driver, where the rest of the
sysfs attributes for the channels are defined. While doing that, make
use of attribute groups and macros, instead of creating sysfs
directly, to ensure better error handling and code flow.
Problematic path:
vmbus_process_offer (A new offer comes for the VMBus device)
vmbus_add_channel_work
vmbus_device_register
|-> device_register
| |...
| |-> hv_uio_probe
| |...
| |-> sysfs_create_bin_file (leads to a warning as
| the primary channel's kobject, which is used to
| create the sysfs file, is not yet initialized)
|-> kset_create_and_add
|-> vmbus_add_channel_kobj (initialization of the primary
channel's kobject happens later)
Above code flow is sequential and the warning is always reproducible in
this path.
Fixes: 9ab877a6cc ("uio_hv_generic: make ring buffer attribute for primary channel")
Cc: stable@kernel.org
Suggested-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Suggested-by: Michael Kelley <mhklinux@outlook.com>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Reviewed-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Naman Jain <namjain@linux.microsoft.com>
Link: https://lore.kernel.org/r/20250502074811.2022-2-namjain@linux.microsoft.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 73fe9073c0 ]
The VMBus driver manages the MMIO space it owns via the hyperv_mmio
resource tree. Because the synthetic video framebuffer portion of the
MMIO space is initially setup by the Hyper-V host for each guest, the
VMBus driver does an early reserve of that portion of MMIO space in the
hyperv_mmio resource tree. It saves a pointer to that resource in
fb_mmio. When a VMBus driver requests MMIO space and passes "true"
for the "fb_overlap_ok" argument, the reserved framebuffer space is
used if possible. In that case it's not necessary to do another request
against the "shadow" hyperv_mmio resource tree because that resource
was already requested in the early reserve steps.
However, the vmbus_free_mmio() function currently does no special
handling for the fb_mmio resource. When a framebuffer device is
removed, or the driver is unbound, the current code for
vmbus_free_mmio() releases the reserved resource, leaving fb_mmio
pointing to memory that has been freed. If the same or another
driver is subsequently bound to the device, vmbus_allocate_mmio()
checks against fb_mmio, and potentially gets garbage. Furthermore
a second unbind operation produces this "nonexistent resource" error
because of the unbalanced behavior between vmbus_allocate_mmio() and
vmbus_free_mmio():
[ 55.499643] resource: Trying to free nonexistent
resource <0x00000000f0000000-0x00000000f07fffff>
Fix this by adding logic to vmbus_free_mmio() to recognize when
MMIO space in the fb_mmio reserved area would be released, and don't
release it. This filtering ensures the fb_mmio resource always exists,
and makes vmbus_free_mmio() more parallel with vmbus_allocate_mmio().
Fixes: be000f93e5 ("drivers:hv: Track allocations of children of hv_vmbus in private resource tree")
Signed-off-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Reviewed-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Link: https://lore.kernel.org/r/20250310035208.275764-1-mhklinux@outlook.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <20250310035208.275764-1-mhklinux@outlook.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 07a756a49f upstream.
If the KVP (or VSS) daemon starts before the VMBus channel's ringbuffer is
fully initialized, we can hit the panic below:
hv_utils: Registering HyperV Utility Driver
hv_vmbus: registering driver hv_utils
...
BUG: kernel NULL pointer dereference, address: 0000000000000000
CPU: 44 UID: 0 PID: 2552 Comm: hv_kvp_daemon Tainted: G E 6.11.0-rc3+ #1
RIP: 0010:hv_pkt_iter_first+0x12/0xd0
Call Trace:
...
vmbus_recvpacket
hv_kvp_onchannelcallback
vmbus_on_event
tasklet_action_common
tasklet_action
handle_softirqs
irq_exit_rcu
sysvec_hyperv_stimer0
</IRQ>
<TASK>
asm_sysvec_hyperv_stimer0
...
kvp_register_done
hvt_op_read
vfs_read
ksys_read
__x64_sys_read
This can happen because the KVP/VSS channel callback can be invoked
even before the channel is fully opened:
1) as soon as hv_kvp_init() -> hvutil_transport_init() creates
/dev/vmbus/hv_kvp, the kvp daemon can open the device file immediately and
register itself to the driver by writing a message KVP_OP_REGISTER1 to the
file (which is handled by kvp_on_msg() ->kvp_handle_handshake()) and
reading the file for the driver's response, which is handled by
hvt_op_read(), which calls hvt->on_read(), i.e. kvp_register_done().
2) the problem with kvp_register_done() is that it can cause the
channel callback to be called even before the channel is fully opened,
and when the channel callback is starting to run, util_probe()->
vmbus_open() may have not initialized the ringbuffer yet, so the
callback can hit the panic of NULL pointer dereference.
To reproduce the panic consistently, we can add a "ssleep(10)" for KVP in
__vmbus_open(), just before the first hv_ringbuffer_init(), and then we
unload and reload the driver hv_utils, and run the daemon manually within
the 10 seconds.
Fix the panic by reordering the steps in util_probe() so the char dev
entry used by the KVP or VSS daemon is not created until after
vmbus_open() has completed. This reordering prevents the race condition
from happening.
Reported-by: Dexuan Cui <decui@microsoft.com>
Fixes: e0fa3e5e7d ("Drivers: hv: utils: fix a race on userspace daemons registration")
Cc: stable@vger.kernel.org
Signed-off-by: Michael Kelley <mhklinux@outlook.com>
Acked-by: Wei Liu <wei.liu@kernel.org>
Link: https://lore.kernel.org/r/20241106154247.2271-3-mhklinux@outlook.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <20241106154247.2271-3-mhklinux@outlook.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull drm updates from Dave Airlie:
"This adds a couple of patches outside the drm core, all should be
acked appropriately, the string and pstore ones are the main ones that
come to mind.
Otherwise it's the usual drivers, xe is getting enabled by default on
some new hardware, we've changed the device number handling to allow
more devices, and we added some optional rust code to create QR codes
in the panic handler, an idea first suggested I think 10 years ago :-)
string:
- add mem_is_zero()
core:
- support more device numbers
- use XArray for minor ids
- add backlight constants
- Split dma fence array creation into alloc and arm
fbdev:
- remove usage of old fbdev hooks
kms:
- Add might_fault() to drm_modeset_lock priming
- Add dynamic per-crtc vblank configuration support
dma-buf:
- docs cleanup
buddy:
- Add start address support for trim function
printk:
- pass description to kmsg_dump
scheduler:
- Remove full_recover from drm_sched_start
ttm:
- Make LRU walk restartable after dropping locks
- Allow direct reclaim to allocate local memory
panic:
- add display QR code (in rust)
displayport:
- mst: GUID improvements
bridge:
- Silence error message on -EPROBE_DEFER
- analogix: Clean aup
- bridge-connector: Fix double free
- lt6505: Disable interrupt when powered off
- tc358767: Make default DP port preemphasis configurable
- lt9611uxc: require DRM_BRIDGE_ATTACH_NO_CONNECTOR
- anx7625: simplify OF array handling
- dw-hdmi: simplify clock handling
- lontium-lt8912b: fix mode validation
- nwl-dsi: fix mode vsync/hsync polarity
xe:
- Enable LunarLake and Battlemage support
- Introducing Xe2 ccs modifiers for integrated and discrete graphics
- rename xe perf to xe observation
- use wb caching on DGFX for system memory
- add fence timeouts
- Lunar Lake graphics/media/display workarounds
- Battlemage workarounds
- Battlemage GSC support
- GSC and HuC fw updates for LL/BM
- use dma_fence_chain_free
- refactor hw engine lookup and mmio access
- enable priority mem read for Xe2
- Add first GuC BMG fw
- fix dma-resv lock
- Fix DGFX display suspend/resume
- Use xe_managed for kernel BOs
- Use reserved copy engine for user binds on faulting devices
- Allow mixing dma-fence jobs and long-running faulting jobs
- fix media TLB invalidation
- fix rpm in TTM swapout path
- track resources and VF state by PF
i915:
- Type-C programming fix for MTL+
- FBC cleanup
- Calc vblank delay more accurately
- On DP MST, Enable LT fallback for UHBR<->non-UHBR rates
- Fix DP LTTPR detection
- limit relocations to INT_MAX
- fix long hangs in buddy allocator on DG2/A380
amdgpu:
- Per-queue reset support
- SDMA devcoredump support
- DCN 4.0.1 updates
- GFX12/VCN4/JPEG4 updates
- Convert vbios embedded EDID to drm_edid
- GFX9.3/9.4 devcoredump support
- process isolation framework for GFX 9.4.3/4
- take IOMMU mappings into account for P2P DMA
amdkfd:
- CRIU fixes
- HMM fix
- Enable process isolation support for GFX 9.4.3/4
- Allow users to target recommended SDMA engines
- KFD support for targetting queues on recommended SDMA engines
radeon:
- remove .load and drm_dev_alloc
- Fix vbios embedded EDID size handling
- Convert vbios embedded EDID to drm_edid
- Use GEM references instead of TTM
- r100 cp init cleanup
- Fix potential overflows in evergreen CS offset tracking
msm:
- DPU:
- implement DP/PHY mapping on SC8180X
- Enable writeback on SM8150, SC8180X, SM6125, SM6350
- DP:
- Enable widebus on all relevant chipsets
- MSM8998 HDMI support
- GPU:
- A642L speedbin support
- A615/A306/A621 support
- A7xx devcoredump support
ast:
- astdp: Support AST2600 with VGA
- Clean up HPD
- Fix timeout loop for DP link training
- reorganize output code by type (VGA, DP, etc)
- convert to struct drm_edid
- fix BMC handling for all outputs
exynos:
- drop stale MAINTAINERS pattern
- constify struct
loongson:
- use GEM refcount over TTM
mgag200:
- Improve BMC handling
- Support VBLANK intterupts
- transparently support BMC outputs
nouveau:
- Refactor and clean up internals
- Use GEM refcount over TTM's
gm12u320:
- convert to struct drm_edid
gma500:
- update i2c terms
lcdif:
- pixel clock fix
host1x:
- fix syncpoint IRQ during resume
- use iommu_paging_domain_alloc()
imx:
- ipuv3: convert to struct drm_edid
omapdrm:
- improve error handling
- use common helper for_each_endpoint_of_node()
panel:
- add support for BOE TV101WUM-LL2 plus DT bindings
- novatek-nt35950: improve error handling
- nv3051d: improve error handling
- panel-edp:
- add support for BOE NE140WUM-N6G
- revert support for SDC ATNA45AF01
- visionox-vtdr6130:
- improve error handling
- use devm_regulator_bulk_get_const()
- boe-th101mb31ig002:
- Support for starry-er88577 MIPI-DSI panel plus DT
- Fix porch parameter
- edp: Support AOU B116XTN02.3, AUO B116XAN06.1, AOU B116XAT04.1, BOE
NV140WUM-N41, BOE NV133WUM-N63, BOE NV116WHM-A4D, CMN N116BCA-EA2,
CMN N116BCP-EA2, CSW MNB601LS1-4
- himax-hx8394: Support Microchip AC40T08A MIPI Display panel plus DT
- ilitek-ili9806e: Support Densitron DMT028VGHMCMI-1D TFT plus DT
- jd9365da:
- Support Melfas lmfbx101117480 MIPI-DSI panel plus DT
- Refactor for code sharing
- panel-edp: fix name for HKC MB116AN01
- jd9365da: fix "exit sleep" commands
- jdi-fhd-r63452: simplify error handling with DSI multi-style
helpers
- mantix-mlaf057we51: simplify error handling with DSI multi-style
helpers
- simple:
- support Innolux G070ACE-LH3 plus DT bindings
- support On Tat Industrial Company KD50G21-40NT-A1 plus DT
bindings
- st7701:
- decouple DSI and DRM code
- add SPI support
- support Anbernic RG28XX plus DT bindings
mediatek:
- support alpha blending
- remove cl in struct cmdq_pkt
- ovl adaptor fix
- add power domain binding for mediatek DPI controller
renesas:
- rz-du: add support for RZ/G2UL plus DT bindings
rockchip:
- Improve DP sink-capability reporting
- dw_hdmi: Support 4k@60Hz
- vop:
- Support RGB display on Rockchip RK3066
- Support 4096px width
sti:
- convert to struct drm_edid
stm:
- Avoid UAF wih managed plane and CRTC helpers
- Fix module owner
- Fix error handling in probe
- Depend on COMMON_CLK
- ltdc:
- Fix transparency after disabling plane
- Remove unused interrupt
tegra:
- gr3d: improve PM domain handling
- convert to struct drm_edid
- Call drm_atomic_helper_shutdown()
vc4:
- fix PM during detect
- replace DRM_ERROR() with drm_error()
- v3d: simplify clock retrieval
v3d:
- Clean up perfmon
virtio:
- add DRM capset"
* tag 'drm-next-2024-09-19' of https://gitlab.freedesktop.org/drm/kernel: (1326 commits)
drm/xe: Fix missing conversion to xe_display_pm_runtime_resume
drm/xe/xe2hpg: Add Wa_15016589081
drm/xe: Don't keep stale pointer to bo->ggtt_node
drm/xe: fix missing 'xe_vm_put'
drm/xe: fix build warning with CONFIG_PM=n
drm/xe: Suppress missing outer rpm protection warning
drm/xe: prevent potential UAF in pf_provision_vf_ggtt()
drm/amd/display: Add all planes on CRTC to state for overlay cursor
drm/i915/bios: fix printk format width
drm/i915/display: Fix BMG CCS modifiers
drm/amdgpu: get rid of bogus includes of fdtable.h
drm/amdkfd: CRIU fixes
drm/amdgpu: fix a race in kfd_mem_export_dmabuf()
drm: new helper: drm_gem_prime_handle_to_dmabuf()
drm/amdgpu/atomfirmware: Silence UBSAN warning
drm/amdgpu: Fix kdoc entry in 'amdgpu_vm_cpu_prepare'
drm/amd/amdgpu: apply command submission parser for JPEG v1
drm/amd/amdgpu: apply command submission parser for JPEG v2+
drm/amd/pm: fix the pp_dpm_pcie issue on smu v14.0.2/3
drm/amd/pm: update the features set on smu v14.0.2/3
...
Pull Hyper-V updates from Wei Liu:
- Optimize boot time by concurrent execution of hv_synic_init()
(Saurabh Sengar)
- Use helpers to read control registers in hv_snp_boot_ap() (Yosry
Ahmed)
- Add memory allocation check in hv_fcopy_start (Zhu Jun)
* tag 'hyperv-next-signed-20240916' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
tools/hv: Add memory allocation check in hv_fcopy_start
x86/hyperv: use helpers to read control registers in hv_snp_boot_ap()
Drivers: hv: vmbus: Optimize boot time by concurrent execution of hv_synic_init()
Thomas needs 5a498d4d06 ("drm/fbdev-dma: Only install deferred I/O
if necessary") in drm-misc, so start the backmerge cascade.
Signed-off-by: Simona Vetter <simona.vetter@ffwll.ch>
Pull hyperv fixes from Wei Liu:
- Add a documentation overview of Confidential Computing VM support
(Michael Kelley)
- Use lapic timer in a TDX VM without paravisor (Dexuan Cui)
- Set X86_FEATURE_TSC_KNOWN_FREQ when Hyper-V provides frequency
(Michael Kelley)
- Fix a kexec crash due to VP assist page corruption (Anirudh
Rayabharam)
- Python3 compatibility fix for lsvmbus (Anthony Nandaa)
- Misc fixes (Rachel Menge, Roman Kisel, zhang jiao, Hongbo Li)
* tag 'hyperv-fixes-signed-20240908' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
hv: vmbus: Constify struct kobj_type and struct attribute_group
tools: hv: rm .*.cmd when make clean
x86/hyperv: fix kexec crash due to VP assist page corruption
Drivers: hv: vmbus: Fix the misplaced function description
tools: hv: lsvmbus: change shebang to use python3
x86/hyperv: Set X86_FEATURE_TSC_KNOWN_FREQ when Hyper-V provides frequency
Documentation: hyperv: Add overview of Confidential Computing VM support
clocksource: hyper-v: Use lapic timer in a TDX VM without paravisor
Drivers: hv: Remove deprecated hv_fcopy declarations
Rescind offer handling relies on rescind callbacks for some of the
resources cleanup, if they are registered. It does not unregister
vmbus device for the primary channel closure, when callback is
registered. Without it, next onoffer does not come, rescind flag
remains set and device goes to unusable state.
Add logic to unregister vmbus for the primary channel in rescind callback
to ensure channel removal and relid release, and to ensure that next
onoffer can be received and handled properly.
Cc: stable@vger.kernel.org
Fixes: ca3cda6fcf ("uio_hv_generic: add rescind support")
Signed-off-by: Naman Jain <namjain@linux.microsoft.com>
Reviewed-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Link: https://lore.kernel.org/r/20240829071312.1595-3-namjain@linux.microsoft.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull driver core updates from Greg KH:
"Here is the big set of driver core changes for 6.11-rc1.
Lots of stuff in here, with not a huge diffstat, but apis are evolving
which required lots of files to be touched. Highlights of the changes
in here are:
- platform remove callback api final fixups (Uwe took many releases
to get here, finally!)
- Rust bindings for basic firmware apis and initial driver-core
interactions.
It's not all that useful for a "write a whole driver in rust" type
of thing, but the firmware bindings do help out the phy rust
drivers, and the driver core bindings give a solid base on which
others can start their work.
There is still a long way to go here before we have a multitude of
rust drivers being added, but it's a great first step.
- driver core const api changes.
This reached across all bus types, and there are some fix-ups for
some not-common bus types that linux-next and 0-day testing shook
out.
This work is being done to help make the rust bindings more safe,
as well as the C code, moving toward the end-goal of allowing us to
put driver structures into read-only memory. We aren't there yet,
but are getting closer.
- minor devres cleanups and fixes found by code inspection
- arch_topology minor changes
- other minor driver core cleanups
All of these have been in linux-next for a very long time with no
reported problems"
* tag 'driver-core-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (55 commits)
ARM: sa1100: make match function take a const pointer
sysfs/cpu: Make crash_hotplug attribute world-readable
dio: Have dio_bus_match() callback take a const *
zorro: make match function take a const pointer
driver core: module: make module_[add|remove]_driver take a const *
driver core: make driver_find_device() take a const *
driver core: make driver_[create|remove]_file take a const *
firmware_loader: fix soundness issue in `request_internal`
firmware_loader: annotate doctests as `no_run`
devres: Correct code style for functions that return a pointer type
devres: Initialize an uninitialized struct member
devres: Fix memory leakage caused by driver API devm_free_percpu()
devres: Fix devm_krealloc() wasting memory
driver core: platform: Switch to use kmemdup_array()
driver core: have match() callback in struct bus_type take a const *
MAINTAINERS: add Rust device abstractions to DRIVER CORE
device: rust: improve safety comments
MAINTAINERS: add Danilo as FIRMWARE LOADER maintainer
MAINTAINERS: add Rust FW abstractions to FIRMWARE LOADER
firmware: rust: improve safety comments
...
kmsg_dump doesn't forward the panic reason string to the kmsg_dumper
callback.
This patch adds a new struct kmsg_dump_detail, that will hold the
reason and description, and pass it to the dump() callback.
To avoid updating all kmsg_dump() call, it adds a kmsg_dump_desc()
function and a macro for backward compatibility.
I've written this for drm_panic, but it can be useful for other
kmsg_dumper.
It allows to see the panic reason, like "sysrq triggered crash"
or "VFS: Unable to mount root fs on xxxx" on the drm panic screen.
v2:
* Use a struct kmsg_dump_detail to hold the reason and description
pointer, for more flexibility if we want to add other parameters.
(Kees Cook)
* Fix powerpc/nvram_64 build, as I didn't update the forward
declaration of oops_to_nvram()
Signed-off-by: Jocelyn Falempe <jfalempe@redhat.com>
Acked-by: Petr Mladek <pmladek@suse.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Kees Cook <kees@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240702122639.248110-1-jfalempe@redhat.com
We currently initialize the memmap such that PG_reserved is set and the
refcount of the page is 1. In virtio-mem code, we have to manually clear
that PG_reserved flag to make memory offlining with partially hotplugged
memory blocks possible: has_unmovable_pages() would otherwise bail out on
such pages.
We want to avoid PG_reserved where possible and move to typed pages
instead. Further, we want to further enlighten memory offlining code
about PG_offline: offline pages in an online memory section. One example
is handling managed page count adjustments in a cleaner way during memory
offlining.
So let's initialize the pages with PG_offline instead of PG_reserved.
generic_online_page()->__free_pages_core() will now clear that flag before
handing that memory to the buddy.
Note that the page refcount is still 1 and would forbid offlining of such
memory except when special care is take during GOING_OFFLINE as currently
only implemented by virtio-mem.
With this change, we can now get non-PageReserved() pages in the XEN
balloon list. From what I can tell, that can already happen via
decrease_reservation(), so that should be fine.
HV-balloon should not really observe a change: partial online memory
blocks still cannot get surprise-offlined, because the refcount of these
PageOffline() pages is 1.
Update virtio-mem, HV-balloon and XEN-balloon code to be aware that
hotplugged pages are now PageOffline() instead of PageReserved() before
they are handed over to the buddy.
We'll leave the ZONE_DEVICE case alone for now.
Note that self-hosted vmemmap pages will no longer be marked as
reserved. This matches ordinary vmemmap pages allocated from the buddy
during memory hotplug. Now, really only vmemmap pages allocated from
memblock during early boot will be marked reserved. Existing
PageReserved() checks seem to be handling all relevant cases correctly
even after this change.
Link: https://lkml.kernel.org/r/20240607090939.89524-3-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Oscar Salvador <osalvador@suse.de> [generic memory-hotplug bits]
Cc: Alexander Potapenko <glider@google.com>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eugenio Pérez <eperezma@redhat.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Marco Elver <elver@google.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
In the match() callback, the struct device_driver * should not be
changed, so change the function callback to be a const *. This is one
step of many towards making the driver core safe to have struct
device_driver in read-only memory.
Because the match() callback is in all busses, all busses are modified
to handle this properly. This does entail switching some container_of()
calls to container_of_const() to properly handle the constant *.
For some busses, like PCI and USB and HV, the const * is cast away in
the match callback as those busses do want to modify those structures at
this point in time (they have a local lock in the driver structure.)
That will have to be changed in the future if they wish to have their
struct device * in read-only-memory.
Cc: Rafael J. Wysocki <rafael@kernel.org>
Reviewed-by: Alex Elder <elder@kernel.org>
Acked-by: Sumit Garg <sumit.garg@linaro.org>
Link: https://lore.kernel.org/r/2024070136-wrongdoer-busily-01e8@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Hyper-V balloon driver supports hot-add of memory in addition
to ballooning. Current code hot-adds in fixed size chunks of
128 MiB (fixed constant HA_CHUNK in the code). While this works
in Hyper-V VMs with 64 GiB or less or memory where the Linux
memblock size is 128 MiB, the hot-add fails for larger memblock
sizes because add_memory() expects memory to be added in chunks
that match the memblock size. Messages like the following are
reported when Linux has a 256 MiB memblock size:
[ 312.668859] Block size [0x10000000] unaligned hotplug range:
start 0x310000000, size 0x8000000
[ 312.668880] hv_balloon: hot_add memory failed error is -22
[ 312.668984] hv_balloon: Memory hot add failed
Larger memblock sizes are usually used in VMs with more than
64 GiB of memory, depending on the alignment of the VM's
physical address space.
Fix this problem by having the Hyper-V balloon driver determine
the Linux memblock size, and process hot-add requests in that
chunk size instead of a fixed 128 MiB. Also update the hot-add
alignment requested of the Hyper-V host to match the memblock
size.
The code changes look significant, but in fact are just a
simple text substitution of a new global variable for the
previous HA_CHUNK constant. No algorithms are changed except
to initialize the new global variable and to calculate the
alignment value to pass to Hyper-V. Testing with memblock
sizes of 256 MiB and 2 GiB shows correct operation.
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Michael Kelley <mhklinux@outlook.com>
Link: https://lore.kernel.org/r/20240503154312.142466-2-mhklinux@outlook.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <20240503154312.142466-2-mhklinux@outlook.com>
Pull char/misc and other driver subsystem updates from Greg KH:
"Here is the big set of char/misc and other driver subsystem updates
for 6.10-rc1. Nothing major here, just lots of new drivers and updates
for apis and new hardware types. Included in here are:
- big IIO driver updates with more devices and drivers added
- fpga driver updates
- hyper-v driver updates
- uio_pruss driver removal, no one uses it, other drivers control the
same hardware now
- binder minor updates
- mhi driver updates
- excon driver updates
- counter driver updates
- accessability driver updates
- coresight driver updates
- other hwtracing driver updates
- nvmem driver updates
- slimbus driver updates
- spmi driver updates
- other smaller misc and char driver updates
All of these have been in linux-next for a while with no reported
issues"
* tag 'char-misc-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (319 commits)
misc: ntsync: mark driver as "broken" to prevent from building
spmi: pmic-arb: Add multi bus support
spmi: pmic-arb: Register controller for bus instead of arbiter
spmi: pmic-arb: Make core resources acquiring a version operation
spmi: pmic-arb: Make the APID init a version operation
spmi: pmic-arb: Fix some compile warnings about members not being described
dt-bindings: spmi: Deprecate qcom,bus-id
dt-bindings: spmi: Add X1E80100 SPMI PMIC ARB schema
spmi: pmic-arb: Replace three IS_ERR() calls by null pointer checks in spmi_pmic_arb_probe()
spmi: hisi-spmi-controller: Do not override device identifier
dt-bindings: spmi: hisilicon,hisi-spmi-controller: clean up example
dt-bindings: spmi: hisilicon,hisi-spmi-controller: fix binding references
spmi: make spmi_bus_type const
extcon: adc-jack: Document missing struct members
extcon: realtek: Remove unused of_gpio.h
extcon: usbc-cros-ec: Convert to platform remove callback returning void
extcon: usb-gpio: Convert to platform remove callback returning void
extcon: max77843: Convert to platform remove callback returning void
extcon: max3355: Convert to platform remove callback returning void
extcon: intel-mrfld: Convert to platform remove callback returning void
...
Pull hyperv fixes from Wei Liu:
- Some cosmetic changes (Erni Sri Satya Vennela, Li Zhijian)
- Introduce hv_numa_node_to_pxm_info() (Nuno Das Neves)
- Fix KVP daemon to handle IPv4 and IPv6 combination for keyfile format
(Shradha Gupta)
- Avoid freeing decrypted memory in a confidential VM (Rick Edgecombe
and Michael Kelley)
* tag 'hyperv-fixes-signed-20240411' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
Drivers: hv: vmbus: Don't free ring buffers that couldn't be re-encrypted
uio_hv_generic: Don't free decrypted memory
hv_netvsc: Don't free decrypted memory
Drivers: hv: vmbus: Track decrypted status in vmbus_gpadl
Drivers: hv: vmbus: Leak pages if set_memory_encrypted() fails
hv/hv_kvp_daemon: Handle IPv4 and Ipv6 combination for keyfile format
hv: vmbus: Convert sprintf() family to sysfs_emit() family
mshyperv: Introduce hv_numa_node_to_pxm_info()
x86/hyperv: Cosmetic changes for hv_apic.c
In CoCo VMs it is possible for the untrusted host to cause
set_memory_encrypted() or set_memory_decrypted() to fail such that an
error is returned and the resulting memory is shared. Callers need to
take care to handle these errors to avoid returning decrypted (shared)
memory to the page allocator, which could lead to functional or security
issues.
The VMBus ring buffer code could free decrypted/shared pages if
set_memory_decrypted() fails. Check the decrypted field in the struct
vmbus_gpadl for the ring buffers to decide whether to free the memory.
Signed-off-by: Michael Kelley <mhklinux@outlook.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Link: https://lore.kernel.org/r/20240311161558.1310-6-mhklinux@outlook.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <20240311161558.1310-6-mhklinux@outlook.com>
In CoCo VMs it is possible for the untrusted host to cause
set_memory_encrypted() or set_memory_decrypted() to fail such that an
error is returned and the resulting memory is shared. Callers need to
take care to handle these errors to avoid returning decrypted (shared)
memory to the page allocator, which could lead to functional or security
issues.
In order to make sure callers of vmbus_establish_gpadl() and
vmbus_teardown_gpadl() don't return decrypted/shared pages to
allocators, add a field in struct vmbus_gpadl to keep track of the
decryption status of the buffers. This will allow the callers to
know if they should free or leak the pages.
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Michael Kelley <mhklinux@outlook.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Link: https://lore.kernel.org/r/20240311161558.1310-3-mhklinux@outlook.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <20240311161558.1310-3-mhklinux@outlook.com>
Pull hyperv updates from Wei Liu:
- Use Hyper-V entropy to seed guest random number generator (Michael
Kelley)
- Convert to platform remove callback returning void for vmbus (Uwe
Kleine-König)
- Introduce hv_get_hypervisor_version function (Nuno Das Neves)
- Rename some HV_REGISTER_* defines for consistency (Nuno Das Neves)
- Change prefix of generic HV_REGISTER_* MSRs to HV_MSR_* (Nuno Das
Neves)
- Cosmetic changes for hv_spinlock.c (Purna Pavan Chandra Aekkaladevi)
- Use per cpu initial stack for vtl context (Saurabh Sengar)
* tag 'hyperv-next-signed-20240320' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
x86/hyperv: Use Hyper-V entropy to seed guest random number generator
x86/hyperv: Cosmetic changes for hv_spinlock.c
hyperv-tlfs: Rename some HV_REGISTER_* defines for consistency
hv: vmbus: Convert to platform remove callback returning void
mshyperv: Introduce hv_get_hypervisor_version function
x86/hyperv: Use per cpu initial stack for vtl context
hyperv-tlfs: Change prefix of generic HV_REGISTER_* MSRs to HV_MSR_*
A Hyper-V host provides its guest VMs with entropy in a custom ACPI
table named "OEM0". The entropy bits are updated each time Hyper-V
boots the VM, and are suitable for seeding the Linux guest random
number generator (rng). See a brief description of OEM0 in [1].
Generation 2 VMs on Hyper-V use UEFI to boot. Existing EFI code in
Linux seeds the rng with entropy bits from the EFI_RNG_PROTOCOL.
Via this path, the rng is seeded very early during boot with good
entropy. The ACPI OEM0 table provided in such VMs is an additional
source of entropy.
Generation 1 VMs on Hyper-V boot from BIOS. For these VMs, Linux
doesn't currently get any entropy from the Hyper-V host. While this
is not fundamentally broken because Linux can generate its own entropy,
using the Hyper-V host provided entropy would get the rng off to a
better start and would do so earlier in the boot process.
Improve the rng seeding for Generation 1 VMs by having Hyper-V specific
code in Linux take advantage of the OEM0 table to seed the rng. For
Generation 2 VMs, use the OEM0 table to provide additional entropy
beyond the EFI_RNG_PROTOCOL. Because the OEM0 table is custom to
Hyper-V, parse it directly in the Hyper-V code in the Linux kernel
and use add_bootloader_randomness() to add it to the rng. Once the
entropy bits are read from OEM0, zero them out in the table so
they don't appear in /sys/firmware/acpi/tables/OEM0 in the running
VM. The zero'ing is done out of an abundance of caution to avoid
potential security risks to the rng. Also set the OEM0 data length
to zero so a kexec or other subsequent use of the table won't try
to use the zero'ed bits.
[1] https://download.microsoft.com/download/1/c/9/1c9813b8-089c-4fef-b2ad-ad80e79403ba/Whitepaper%20-%20The%20Windows%2010%20random%20number%20generation%20infrastructure.pdf
Signed-off-by: Michael Kelley <mhklinux@outlook.com>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Link: https://lore.kernel.org/r/20240318155408.216851-1-mhklinux@outlook.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <20240318155408.216851-1-mhklinux@outlook.com>
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.
To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().
Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/920230729ddbeb9f3c4ff8282a18b0c0e1a37969.1709886922.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <920230729ddbeb9f3c4ff8282a18b0c0e1a37969.1709886922.git.u.kleine-koenig@pengutronix.de>
The HV_REGISTER_ are used as arguments to hv_set/get_register(), which
delegate to arch-specific mechanisms for getting/setting synthetic
Hyper-V MSRs.
On arm64, HV_REGISTER_ defines are synthetic VP registers accessed via
the get/set vp registers hypercalls. The naming matches the TLFS
document, although these register names are not specific to arm64.
However, on x86 the prefix HV_REGISTER_ indicates Hyper-V MSRs accessed
via rdmsrl()/wrmsrl(). This is not consistent with the TLFS doc, where
HV_REGISTER_ is *only* used for used for VP register names used by
the get/set register hypercalls.
To fix this inconsistency and prevent future confusion, change the
arch-generic aliases used by callers of hv_set/get_register() to have
the prefix HV_MSR_ instead of HV_REGISTER_.
Use the prefix HV_X64_MSR_ for the x86-only Hyper-V MSRs. On x86, the
generic HV_MSR_'s point to the corresponding HV_X64_MSR_.
Move the arm64 HV_REGISTER_* defines to the asm-generic hyperv-tlfs.h,
since these are not specific to arm64. On arm64, the generic HV_MSR_'s
point to the corresponding HV_REGISTER_.
While at it, rename hv_get/set_registers() and related functions to
hv_get/set_msr(), hv_get/set_nested_msr(), etc. These are only used for
Hyper-V MSRs and this naming makes that clear.
Signed-off-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
Reviewed-by: Wei Liu <wei.liu@kernel.org>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Link: https://lore.kernel.org/r/1708440933-27125-1-git-send-email-nunodasneves@linux.microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <1708440933-27125-1-git-send-email-nunodasneves@linux.microsoft.com>
create_gpadl_header() creates a message header, and one or more message
bodies if the number of GPADL entries exceeds what fits in the
header. Currently the code for creating the message header is
duplicated in the two halves of the main "if" statement governing
whether message bodies are created.
Eliminate the duplication by making minor tweaks to the logic and
associated comments. While here, simplify the handling of memory
allocation errors, and use umin() instead of open coding it.
For ease of review, the indentation of sizable chunks of code is
*not* changed. A follow-on patch updates only the indentation.
No functional change.
Suggested-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Michael Kelley <mhklinux@outlook.com>
Link: https://lore.kernel.org/r/20240111165451.269418-1-mhklinux@outlook.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <20240111165451.269418-1-mhklinux@outlook.com>
Pull tty and serial updates from Greg KH:
"Here is the big set of tty/serial driver changes for 6.7-rc1. Included
in here are:
- console/vgacon cleanups and removals from Arnd
- tty core and n_tty cleanups from Jiri
- lots of 8250 driver updates and cleanups
- sc16is7xx serial driver updates
- dt binding updates
- first set of port lock wrapers from Thomas for the printk fixes
coming in future releases
- other small serial and tty core cleanups and updates
All of these have been in linux-next for a while with no reported
issues"
* tag 'tty-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (193 commits)
serdev: Replace custom code with device_match_acpi_handle()
serdev: Simplify devm_serdev_device_open() function
serdev: Make use of device_set_node()
tty: n_gsm: add copyright Siemens Mobility GmbH
tty: n_gsm: fix race condition in status line change on dead connections
serial: core: Fix runtime PM handling for pending tx
vgacon: fix mips/sibyte build regression
dt-bindings: serial: drop unsupported samsung bindings
tty: serial: samsung: drop earlycon support for unsupported platforms
tty: 8250: Add note for PX-835
tty: 8250: Fix IS-200 PCI ID comment
tty: 8250: Add Brainboxes Oxford Semiconductor-based quirks
tty: 8250: Add support for Intashield IX cards
tty: 8250: Add support for additional Brainboxes PX cards
tty: 8250: Fix up PX-803/PX-857
tty: 8250: Fix port count of PX-257
tty: 8250: Add support for Intashield IS-100
tty: 8250: Add support for Brainboxes UP cards
tty: 8250: Add support for additional Brainboxes UC cards
tty: 8250: Remove UC-257 and UC-431
...
