Defining the FGU behaviour is extremely tedious. It relies on matching
each set of bits from FGT registers with am architectural feature, and
adding them to the FGU list if the corresponding feature isn't advertised
to the guest.
It is however relatively easy to dump most of that information from
the architecture JSON description, and use that to control the FGU bits.
Let's introduce a new set of tables descripbing the mapping between
FGT bits and features. Most of the time, this is only a lookup in
an idreg field, with a few more complex exceptions.
While this is obviously many more lines in a new file, this is
mostly generated, and is pretty easy to maintain.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
The architecture introduces a trap for PSB CSYNC that fits in
the same EC as LS64. Let's deal with it in a similar way as
LS64.
It's not that we expect this to be useful any time soon anyway.
Signed-off-by: Marc Zyngier <maz@kernel.org>
We do not have a computed table for HCRX_EL2, so statically define
the bits we know about. A warning will fire if the architecture
grows bits that are not handled yet.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Flip the hyervisor FGT configuration over to the computed FGT
masks.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
The nVHE hypervisor needs to have access to its own view of the FGT
masks, which unfortunately results in a bit of data duplication.
Signed-off-by: Marc Zyngier <maz@kernel.org>
... otherwise we can inherit the host configuration if this differs from
the KVM configuration.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
[maz: simplified a couple of things]
Signed-off-by: Marc Zyngier <maz@kernel.org>
The current FTP tables are only concerned with the bits generating
ESR_ELx.EC==0x18. However, we want an exhaustive view of what KVM
really knows about.
So let's add another small table that provides that extra information.
Signed-off-by: Marc Zyngier <maz@kernel.org>
In the process of decoupling KVM's view of the FGT bits from the
wider architectural state, use KVM's own FGT tables to build
a synthetic view of what is actually known.
This allows for some checking along the way.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
We don't seem to be handling the GCS-specific exception class.
Handle it by delivering an UNDEF to the guest, and populate the
relevant trap bits.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Treating HCRX_EL2 as yet another FGT register seems excessive, and
gets in a way of further improvements. It is actually simpler to
just be explicit about the masking, so just to that.
Signed-off-by: Marc Zyngier <maz@kernel.org>
We currently unconditionally make ACCDATA_EL1 accesses UNDEF.
As we are about to support it, restrict the UNDEF behaviour to cases
where FEAT_LS64_ACCDATA is not exposed to the guest.
Signed-off-by: Marc Zyngier <maz@kernel.org>
We generally don't expect FEAT_LS64* instructions to trap, unless
they are trapped by a guest hypervisor.
Otherwise, this is just the guest playing tricks on us by using
an instruction that isn't advertised, which we handle with a well
deserved UNDEF.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
check_fgt_bit() and triage_sysreg_trap() implement the same thing
twice for no good reason. We have to lookup the FGT register twice,
as we don't communicate it. Similarly, we extract the register value
at the wrong spot.
Reorganise the code in a more logical way so that things are done
at the correct location, removing a lot of duplication.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
triage_sysreg_trap() assumes that it knows all the possible values
for FGT groups, which won't be the case as we start adding more
FGT registers (unless we add everything in one go, which is obviously
undesirable).
At the same time, it doesn't offer much in terms of debugging info
when things go wrong.
Turn the "__NR_FGT_GROUP_IDS__" case into a default, covering any
unhandled value, and give the kernel hacker a bit of a clue about
what's wrong (system register and full trap descriptor).
Signed-off-by: Marc Zyngier <maz@kernel.org>
As we will eventually have to context-switch the FEAT_FGT2 registers
in KVM (something that has been completely ignored so far), add
a new cap that we will be able to check for.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Provide the architected EC and ISS values for all the FEAT_LS64*
instructions.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Bulk addition of all the system registers trapped by HDFG{R,W}TR2_EL2.
The descriptions are extracted from the BSD-licenced JSON file part
of the 2025-03 drop from ARM.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Bulk addition of all the system registers trapped by HFG{R,W}TR2_EL2.
The descriptions are extracted from the BSD-licenced JSON file part
of the 2025-03 drop from ARM.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Treating HFGRTR_EL2 and HFGWTR_EL2 identically was a mistake.
It makes things hard to reason about, has the potential to
introduce bugs by giving a meaning to bits that are really reserved,
and is in general a bad description of the architecture.
Given that #defines are cheap, let's describe both registers as
intended by the architecture, and repaint all the existing uses.
Yes, this is painful.
The registers themselves are generated from the JSON file in
an automated way.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Add HCR_EL2 to the sysreg file, more or less directly generated
from the JSON file.
Since the generated names significantly differ from the existing
naming, express the old names in terms of the new one. One day, we'll
fix this mess, but I'm not in any hurry.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Resync the ID_AA64MMFR4_EL1 with the architectue description.
This results in:
- the new PoPS field
- the new NV2P1 value for the NV_frac field
- the new RMEGDI field
- the new SRMASK field
These fields have been generated from the reference JSON file.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
The 2024 extensions are adding yet another variant of LS64
(aptly named FEAT_LS64WB) supporting LS64 accesses to write-back
memory, as well as 32 byte single-copy atomic accesses using pairs
of FP registers.
Add the relevant encoding to ID_AA64ISAR1_EL1.LS64.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
The C sequence points are complicated things, and gcc-15 has apparently
added a warning for the case where an object is both used and modified
multiple times within the same sequence point.
That's a great warning.
Or rather, it would be a great warning, except gcc-15 seems to not
really be very exact about it, and doesn't notice that the modification
are to two entirely different members of the same object: the array
counter and the array entries.
So that seems kind of silly.
That said, the code that gcc complains about is unnecessarily
complicated, so moving the array counter update into a separate
statement seems like the most straightforward fix for these warnings:
drivers/net/wireless/intel/iwlwifi/mld/d3.c: In function ‘iwl_mld_set_netdetect_info’:
drivers/net/wireless/intel/iwlwifi/mld/d3.c:1102:66: error: operation on ‘netdetect_info->n_matches’ may be undefined [-Werror=sequence-point]
1102 | netdetect_info->matches[netdetect_info->n_matches++] = match;
| ~~~~~~~~~~~~~~~~~~~~~~~~~^~
drivers/net/wireless/intel/iwlwifi/mld/d3.c:1120:58: error: operation on ‘match->n_channels’ may be undefined [-Werror=sequence-point]
1120 | match->channels[match->n_channels++] =
| ~~~~~~~~~~~~~~~~~^~
side note: the code at that second warning is actively buggy, and only
works on little-endian machines that don't do strict alignment checks.
The code casts an array of integers into an array of unsigned long in
order to use our bitmap iterators. That happens to work fine on any
sane architecture, but it's still wrong.
This does *not* fix that more serious problem. This only splits the two
assignments into two statements and fixes the compiler warning. I need
to get rid of the new warnings in order to be able to actually do any
build testing.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
All of these cases are perfectly valid and good traditional C, but hit
by the "you're not NUL-terminating your byte array" warning.
And none of the cases want any terminating NUL character.
Mark them __nonstring to shut up gcc-15 (and in the case of the ak8974
magnetometer driver, I just removed the explicit array size and let gcc
expand the 3-byte and 6-byte arrays by one extra byte, because it was
the simpler change).
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This removes two cases of explicit NUL padding that now causes warnings
because of '-Wunterminated-string-initialization' being part of -Wextra
in gcc-15.
Gcc is being silly in this case when it says that it truncates a NUL
terminator, because in these cases there were _multiple_ NUL characters.
But we can get rid of the warning by just simplifying the two
initializers that trigger the warning for me, so this does exactly that.
I'm not sure why the power supply code did that odd
.attr_name = #_name "\0",
pattern: it was introduced in commit 2cabeaf151 ("power: supply: core:
Cleanup power supply sysfs attribute list"), but that 'attr_name[]'
field is an explicitly sized character array in a statically initialized
variable, and a string initializer always has a terminating NUL _and_
statically initialized character arrays are zero-padded anyway, so it
really seems to be rather extraneous belt-and-suspenders.
The zero_uuid[16] initialization in drivers/md/bcache/super.c makes
perfect sense, but it isn't necessary for the same reasons, and not
worth the new gcc warning noise.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is not great: I'd much rather introduce a typedef that is a "ACPI
name byte buffer", and use that to mark these special 4-byte ACPI names
that do not use NUL termination.
But as noted in the previous commit ("gcc-15: make 'unterminated string
initialization' just a warning") gcc doesn't actually seem to support
that notion, so instead you have to just mark every single array
declaration individually.
So this is not pretty, but this gets rid of the bulk of the annoying
warnings during an allmodconfig build for me.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
gcc-15 enabling -Wunterminated-string-initialization in -Wextra by
default was done with the best intentions, but the warning is still
quite broken.
What annoys me about the warning is that this is a very traditional AND
CORRECT way to initialize fixed byte arrays in C:
unsigned char hex[16] = "0123456789abcdef";
and we use this all over the kernel. And the warning is fine, but gcc
developers apparently never made a reasonable way to disable it. As is
(sadly) tradition with these things.
Yes, there's "__attribute__((nonstring))", and we have a macro to make
that absolutely disgusting syntax more palatable (ie the kernel syntax
for that monstrosity is just "__nonstring").
But that attribute is misdesigned. What you'd typically want to do is
tell the compiler that you are using a type that isn't a string but a
byte array, but that doesn't work at all:
warning: ‘nonstring’ attribute does not apply to types [-Wattributes]
and because of this fundamental mis-design, you then have to mark each
instance of that pattern.
This is particularly noticeable in our ACPI code, because ACPI has this
notion of a 4-byte "type name" that gets used all over, and is exactly
this kind of byte array.
This is a sad oversight, because the warning is useful, but really would
be so much better if gcc had also given a sane way to indicate that we
really just want a byte array type at a type level, not the broken "each
and every array definition" level.
So now instead of creating a nice "ACPI name" type using something like
typedef char acpi_name_t[4] __nonstring;
we have to do things like
char name[ACPI_NAMESEG_SIZE] __nonstring;
in every place that uses this concept and then happens to have the
typical initializers.
This is annoying me mainly because I think the warning _is_ a good
warning, which is why I'm not just turning it off in disgust. But it is
hampered by this bad implementation detail.
[ And obviously I'm doing this now because system upgrades for me are
something that happen in the middle of the release cycle: don't do it
before or during travel, or just before or during the busy merge
window period. ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull misc hotfixes from Andrew Morton:
"16 hotfixes. 2 are cc:stable and the remainder address post-6.14
issues or aren't considered necessary for -stable kernels.
All patches are basically for MM although five are alterations to
MAINTAINERS"
[ Basic counting skills are clearly not a strictly necessary requirement
for kernel maintainers. - Linus ]
* tag 'mm-hotfixes-stable-2025-04-19-21-24' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
MAINTAINERS: add section for locking of mm's and VMAs
mm: vmscan: fix kswapd exit condition in defrag_mode
mm: vmscan: restore high-cpu watermark safety in kswapd
MAINTAINERS: add Pedro as reviewer to the MEMORY MAPPING section
mm/memory: move sanity checks in do_wp_page() after mapcount vs. refcount stabilization
mm, hugetlb: increment the number of pages to be reset on HVO
writeback: fix false warning in inode_to_wb()
docs: ABI: replace mcroce@microsoft.com with new Meta address
mm/gup: fix wrongly calculated returned value in fault_in_safe_writeable()
MAINTAINERS: add memory advice section
MAINTAINERS: add mmap trace events to MEMORY MAPPING
mm: memcontrol: fix swap counter leak from offline cgroup
MAINTAINERS: add MM subsection for the page allocator
MAINTAINERS: update SLAB ALLOCATOR maintainers
fs/dax: fix folio splitting issue by resetting old folio order + _nr_pages
mm/page_alloc: fix deadlock on cpu_hotplug_lock in __accept_page()
Pull vfs fixes from Christian Brauner:
- Revert the hfs{plus} deprecation warning that's also included in this
pull request. The commit introducing the deprecation warning resides
rather early in this branch. So simply dropping it would've rebased
all other commits which I decided to avoid. Hence the revert in the
same branch
[ Background - the deprecation warning discussion resulted in people
stepping up, and so hfs{plus} will have a maintainer taking care of
it after all.. - Linus ]
- Switch CONFIG_SYSFS_SYCALL default to n and decouple from
CONFIG_EXPERT
- Fix an audit bug caused by changes to our kernel path lookup helpers
this cycle. Audit needs the parent path even if the dentry it tried
to look up is negative
- Ensure that the kernel path lookup helpers leave the passed in path
argument clean when they return an error. This is consistent with all
our other helpers
- Ensure that vfs_getattr_nosec() calls bdev_statx() so the relevant
information is available to kernel consumers as well
- Don't set a timer and call schedule() if the timer will expire
immediately in epoll
- Make netfs lookup tables with __nonstring
* tag 'vfs-6.15-rc3.fixes.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
Revert "hfs{plus}: add deprecation warning"
fs: move the bdex_statx call to vfs_getattr_nosec
netfs: Mark __nonstring lookup tables
eventpoll: Set epoll timeout if it's in the future
fs: ensure that *path_locked*() helpers leave passed path pristine
fs: add kern_path_locked_negative()
hfs{plus}: add deprecation warning
Kconfig: switch CONFIG_SYSFS_SYCALL default to n
This reverts commit ddee68c499.
There's ongoing discussion about better maintenance of at least hfsplus.
Rever the deprecation warning for now.
Signed-off-by: Christian Brauner <brauner@kernel.org>
Pull tracing fixes from Steven Rostedt:
- Initialize hash variables in ftrace subops logic
The fix that simplified the ftrace subops logic opened a path where
some variables could be used without being initialized, and done
subtly where the compiler did not catch it. Initialize those
variables to the EMPTY_HASH, which is the default hash.
- Reinitialize the hash pointers after they are freed
Some of the hash pointers in the subop logic were freed but may still
be referenced later. To prevent use-after-free bugs, initialize them
back to the EMPTY_HASH.
- Free the ftrace hashes when they are replaced
The fix that simplified the subops logic updated some hash pointers,
but left the original hash that they were pointing to where they are
no longer used. This caused a memory leak. Free the hashes that are
pointed to by the pointers when they are replaced.
- Fix size initialization of ftrace direct function hash
The ftrace direct function hash used by BPF initialized the hash size
incorrectly. It checked the size of items to a hard coded 32, which
made the hash bit size of 5. The hash size is supposed to be limited
by the bit size of the hash, as the bitmask is allowed to be greater
than 5. Rework the size check to first pass the number of elements to
fls() and then compare that to FTRACE_HASH_MAX_BITS before allocating
the hash.
- Fix format output of ftrace_graph_ent_entry event
The field depth of the ftrace_graph_ent_entry event is of size 4 but
the output showed it as unsigned long and use "%lu". Change it to
unsigned int and use "%u" in the print format that is displayed to
user space.
- Fix the trace event filter on strings
Events can be filtered on numbers or string values. The return value
checked from strncpy_from_kernel_nofault() and
strncpy_from_user_nofault() was used to determine if reading the
strings would fault or not. It would return fault if the value was
non zero, which is basically meant that it was always considering the
read as a fault.
- Add selftest to test trace event string filtering
In order to catch the breakage of the string filtering, add a self
test to make sure that it continues to work.
* tag 'trace-v6.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: selftests: Add testing a user string to filters
tracing: Fix filter string testing
ftrace: Fix type of ftrace_graph_ent_entry.depth
ftrace: fix incorrect hash size in register_ftrace_direct()
ftrace: Free ftrace hashes after they are replaced in the subops code
ftrace: Reinitialize hash to EMPTY_HASH after freeing
ftrace: Initialize variables for ftrace_startup/shutdown_subops()
Pull nfsd fixes from Chuck Lever:
- v6.15 libcrc clean-up makes invalid configurations possible
- Fix a potential deadlock introduced during the v6.15 merge window
* tag 'nfsd-6.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
nfsd: decrease sc_count directly if fail to queue dl_recall
nfs: add missing selections of CONFIG_CRC32
Pull rust fixes from Miguel Ojeda:
"Toolchain and infrastructure:
- Fix missing KASAN LLVM flags on first build (and fix spurious
rebuilds) by skipping '--target'
- Fix Make < 4.3 build error by using '$(pound)'
- Fix UML build error by removing 'volatile' qualifier from io
helpers
- Fix UML build error by adding 'dma_{alloc,free}_attrs()' helpers
- Clean gendwarfksyms warnings by avoiding to export '__pfx' symbols
- Clean objtool warning by adding a new 'noreturn' function for
1.86.0
- Disable 'needless_continue' Clippy lint due to new 1.86.0 warnings
- Add missing 'ffi' crate to 'generate_rust_analyzer.py'
'pin-init' crate:
- Import a couple fixes from upstream"
* tag 'rust-fixes-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux:
rust: helpers: Add dma_alloc_attrs() and dma_free_attrs()
rust: helpers: Remove volatile qualifier from io helpers
rust: kbuild: use `pound` to support GNU Make < 4.3
objtool/rust: add one more `noreturn` Rust function for Rust 1.86.0
rust: kasan/kbuild: fix missing flags on first build
rust: disable `clippy::needless_continue`
rust: kbuild: Don't export __pfx symbols
rust: pin-init: use Markdown autolinks in Rust comments
rust: pin-init: alloc: restrict `impl ZeroableOption` for `Box` to `T: Sized`
scripts: generate_rust_analyzer: Add ffi crate
Pull drm fixes from Dave Airlie:
"Easter rc3 pull request, fixes in all the usuals, amdgpu, xe, msm,
with some i915/ivpu/mgag200/v3d fixes, then a couple of bits in
dma-buf/gem.
Hopefully has no easter eggs in it.
dma-buf:
- Correctly decrement refcounter on errors
gem:
- Fix test for imported buffers
amdgpu:
- Cleaner shader sysfs fix
- Suspend fix
- Fix doorbell free ordering
- Video caps fix
- DML2 memory allocation optimization
- HDP fix
i915:
- Fix DP DSC configurations that require 3 DSC engines per pipe
xe:
- Fix LRC address being written too late for GuC
- Fix notifier vs folio deadlock
- Fix race betwen dma_buf unmap and vram eviction
- Fix debugfs handling PXP terminations unconditionally
msm:
- Display:
- Fix to call dpu_plane_atomic_check_pipe() for both SSPPs in
case of multi-rect
- Fix to validate plane_state pointer before using it in
dpu_plane_virtual_atomic_check()
- Fix to make sure dereferencing dpu_encoder_phys happens after
making sure it is valid in _dpu_encoder_trigger_start()
- Remove the remaining intr_tear_rd_ptr which we initialized to
-1 because NO_IRQ indices start from 0 now
- GPU:
- Fix IB_SIZE overflow
ivpu:
- Fix debugging
- Fixes to frequency
- Support firmware API 3.28.3
- Flush jobs upon reset
mgag200:
- Set vblank start to correct values
v3d:
- Fix Indirect Dispatch"
* tag 'drm-fixes-2025-04-19' of https://gitlab.freedesktop.org/drm/kernel: (26 commits)
drm/msm/a6xx+: Don't let IB_SIZE overflow
drm/xe/pxp: do not queue unneeded terminations from debugfs
drm/xe/dma_buf: stop relying on placement in unmap
drm/xe/userptr: fix notifier vs folio deadlock
drm/xe: Set LRC addresses before guc load
drm/mgag200: Fix value in <VBLKSTR> register
drm/gem: Internally test import_attach for imported objects
drm/amdgpu: Use the right function for hdp flush
drm/amd/display/dml2: use vzalloc rather than kzalloc
drm/amdgpu: Add back JPEG to video caps for carrizo and newer
drm/amdgpu: fix warning of drm_mm_clean
drm/amd: Forbid suspending into non-default suspend states
drm/amdgpu: use a dummy owner for sysfs triggered cleaner shaders v4
drm/i915/dp: Check for HAS_DSC_3ENGINES while configuring DSC slices
drm/i915/display: Add macro for checking 3 DSC engines
dma-buf/sw_sync: Decrement refcount on error in sw_sync_ioctl_get_deadline()
accel/ivpu: Add cmdq_id to job related logs
accel/ivpu: Show NPU frequency in sysfs
accel/ivpu: Fix the NPU's DPU frequency calculation
accel/ivpu: Update FW Boot API to version 3.28.3
...
Fixes for v6.15-rc3
Display:
- Fix to call dpu_plane_atomic_check_pipe() for both SSPPs in
case of multi-rect
- Fix to validate plane_state pointer before using it in
dpu_plane_virtual_atomic_check()
- Fix to make sure dereferencing dpu_encoder_phys happens after
making sure it is valid in _dpu_encoder_trigger_start()
- Remove the remaining intr_tear_rd_ptr which we initialized
to -1 because NO_IRQ indices start from 0 now
GPU:
- Fix IB_SIZE overflow
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Rob Clark <robdclark@gmail.com>
Link: https://lore.kernel.org/r/CAF6AEGtVKXEVdzUzFWmQE8JmK3nx_hp+ynOd-5j3vnfcU-sgOA@mail.gmail.com
Pull smb client fixes from Steve French:
- Fix hard link lease key problem when close is deferred
- Revert the socket lockdep/refcount workarounds done in cifs.ko now
that it is fixed at the socket layer
* tag '6.15-rc2-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
Revert "smb: client: fix TCP timers deadlock after rmmod"
Revert "smb: client: Fix netns refcount imbalance causing leaks and use-after-free"
smb3 client: fix open hardlink on deferred close file error
IB_SIZE is only b0..b19. Starting with a6xx gen3, additional fields
were added above the IB_SIZE. Accidentially setting them can cause
badness. Fix this by properly defining the CP_INDIRECT_BUFFER packet
and using the generated builder macro to ensure unintended bits are not
set.
v2: add missing type attribute for IB_BASE
v3: fix offset attribute in xml
Reported-by: Connor Abbott <cwabbott0@gmail.com>
Fixes: a83366ef19 ("drm/msm/a6xx: add A640/A650 to gpulist")
Signed-off-by: Rob Clark <robdclark@chromium.org>
Patchwork: https://patchwork.freedesktop.org/patch/643396/
