We mux multiple calls to the drivers via the .get_nfc and .set_nfc
callbacks. This is slightly inconvenient to the drivers as they
have to de-mux them back. It will also be awkward for netlink code
to construct struct ethtool_rxnfc when it wants to get info about
RX Flow Hash, from the RSS module.
Add dedicated driver callbacks. Create struct ethtool_rxfh_fields
which contains only data relevant to RXFH. Maintain the names of
the fields to avoid having to heavily modify the drivers.
For now support both callbacks, once all drivers are converted
ethtool_*et_rxfh_fields() will stop using the rxnfc callbacks.
Link: https://patch.msgid.link/20250611145949.2674086-5-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
RX Flow Hashing supports using different configuration for different
RSS contexts. Only two drivers seem to support it. Make sure we
uniformly error out for drivers which don't.
Reviewed-by: Joe Damato <joe@dama.to>
Link: https://patch.msgid.link/20250611145949.2674086-4-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Now that the handles have been separated - remove the RX Flow Hash
handling from rxnfc functions and vice versa.
Reviewed-by: Joe Damato <joe@dama.to>
Link: https://patch.msgid.link/20250611145949.2674086-3-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
RX Flow Hash configuration uses the same argument structure
as flow filters. This is probably why ethtool IOCTL handles
them together. The more checks we add the more convoluted
this code is getting (as some of the checks apply only
to flow filters and others only to the hashing).
Copy the code to separate the handling. This is an exact
copy, the next change will remove unnecessary handling.
Reviewed-by: Joe Damato <joe@dama.to>
Link: https://patch.msgid.link/20250611145949.2674086-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When injecting fault to xe_guc_ct_send_recv() & xe_guc_mmio_send_recv()
functions, the CI test systems are going out of space and crashing. To
avoid this issue, a new helper function is created and when fault is
injected into this xe_is_injection_active() helper function, ct dead
capture is avoided which suppresses ct dumps in the log.
Signed-off-by: Satyanarayana K V P <satyanarayana.k.v.p@intel.com>
Suggested-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: John Harrison <John.C.Harrison@Intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://lore.kernel.org/r/20250612080402.22011-1-satyanarayana.k.v.p@intel.com
With input changed == NULL, a local variable is used for "changed".
Initialize tmp properly, so that it can be used in the following:
*changed |= err > 0;
Otherwise, UBSAN will complain:
UBSAN: invalid-load in kernel/bpf/verifier.c:18924:4
load of value <some random value> is not a valid value for type '_Bool'
Fixes: dfb2d4c64b ("bpf: set 'changed' status if propagate_liveness() did any updates")
Signed-off-by: Song Liu <song@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250612221100.2153401-1-song@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
When xsend() returns -1 (error), the check 'n < sizeof(buf)' incorrectly
treats it as success due to unsigned promotion. Explicitly check for -1
first.
Fixes: a4b7193d8e ("selftests/bpf: Add sockmap test for redirecting partial skb data")
Signed-off-by: Fushuai Wang <wangfushuai@baidu.com>
Link: https://lore.kernel.org/r/20250612084208.27722-1-wangfushuai@baidu.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Without this, `state->speculative` is used after the cleanup cycles in
push_stack() or push_async_cb() freed `env->cur_state` (i.e., `state`).
Avoid this by relying on the short-circuit logic to only access `state`
if the error is recoverable (and make sure it never is after push_*()
failed).
push_*() callers must always return an error for which
error_recoverable_with_nospec(err) is false if push_*() returns NULL,
otherwise we try to recover and access the stale `state`. This is only
violated by sanitize_ptr_alu(), thus also fix this case to return
-ENOMEM.
state->speculative does not make sense if the error path of push_*()
ran. In that case, `state->speculative &&
error_recoverable_with_nospec(err)` as a whole should already never
evaluate to true (because all cases where push_stack() fails must return
-ENOMEM/-EFAULT). As mentioned, this is only violated by the
push_stack() call in sanitize_speculative_path() which returns -EACCES
without [1] (through REASON_STACK in sanitize_err() after
sanitize_ptr_alu()). To fix this, return -ENOMEM for REASON_STACK (which
is also the behavior we will have after [1]).
Checked that it fixes the syzbot reproducer as expected.
[1] https://lore.kernel.org/all/20250603213232.339242-1-luis.gerhorst@fau.de/
Fixes: d6f1c85f22 ("bpf: Fall back to nospec for Spectre v1")
Reported-by: syzbot+b5eb72a560b8149a1885@syzkaller.appspotmail.com
Reported-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/all/38862a832b91382cddb083dddd92643bed0723b8.camel@gmail.com/
Signed-off-by: Luis Gerhorst <luis.gerhorst@fau.de>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250611210728.266563-1-luis.gerhorst@fau.de
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Eduard Zingerman says:
====================
bpf: propagate read/precision marks over state graph backedges
Current loop_entry-based states comparison logic does not handle the
following case:
.-> A --. Assume the states are visited in the order A, B, C.
| | | Assume that state B reaches a state equivalent to state A.
| v v At this point, state C is not processed yet, so state A
'-- B C has not received any read or precision marks from C.
As a result, these marks won't be propagated to B.
If B has incomplete marks, it is unsafe to use it in states_equal()
checks. This issue was first reported in [1].
This patch-set
--------------
Here is the gist of the algorithm implemented by this patch-set:
- Compute strongly connected components (SCCs) in the program CFG.
- When a verifier state enters an SCC, that state is recorded as the
SCC's entry point.
- When a verifier state is found to be equivalent to another
(e.g., B to A in the example above), it is recorded as a
states-graph backedge.
- Backedges are accumulated per SCC (*).
- When an SCC entry state reaches `branches == 0`, propagate read and
precision marks through the backedges until a fixed point is reached
(e.g., from A to B, from C to A, and then again from A to B).
(*) This is an oversimplification, see patch #8 for details.
Unfortunately, this means that commit [2] needs to be reverted,
as precision propagation requires access to jump history,
and backedges represent history not belonging to `env->cur_state`.
Details are provided in patch #8; a comment in `is_state_visited()`
explains most of the mechanics.
Patch #2 adds a `compute_scc()` function, which computes SCCs in the
program CFG. This function was tested using property-based testing in
[3], but it is not included in selftests.
Previous attempt
----------------
A previous attempt to fix this is described in [4]:
1. Within the states loop, `states_equal(... RANGE_WITHIN)` ignores
read and precision marks.
2. For states outside the loop, all registers for states within the
loop are marked as read and precise.
This approach led to an 86x regression on the `cond_break1` selftest.
In that test, one loop was followed by another, and a certain variable
was incremented in the second loop. This variable was marked as
precise due to rule (2), which hindered convergence in the first loop.
After some off-list discussion, it was decided that this might be a
typical case and such regressions are undesirable.
This patch-set avoids such eager precision markings.
Alternatives
------------
Another option is to associate a mask of read/written/precise stack
slots with each instruction. This mask can be populated during
verifier states exploration. Upon reaching an `EXIT` instruction or an
equivalent state, the accumulated masks can be used to propagate
read/written/precise bits across the program's control flow graph
using an analysis similar to use-def.
Unfortunately, a naive implementation of this approach [5] results in
a 10x regression in `veristat` for some `sched_ext` programs due to
the inability to express the must-write property. This issue requires
further investigation.
Changes in verification performance
-----------------------------------
There are some veristat regressions when comparing with master using
selftests and sched_ext BPF binaries. The comparison is done using
master from [6] and this patch-set from [7] where memory accounting
logic is added to veristat.
========= selftests: master vs patch-set =========
File Program Insns Peak memory (KiB)
--------------------- ----------------------------------- ----- ----- ---------------- ---- ----- ----------------
bpf_qdisc_fq.bpf.o bpf_fq_dequeue 1187 1645 +458 (+38.58%) 768 1240 +472 (+61.46%)
dynptr_success.bpf.o test_copy_from_user_str_dynptr 208 279 +71 (+34.13%) 512 1024 +512 (+100.00%)
dynptr_success.bpf.o test_copy_from_user_task_str_dynptr 205 263 +58 (+28.29%) 512 1024 +512 (+100.00%)
dynptr_success.bpf.o test_probe_read_kernel_str_dynptr 686 857 +171 (+24.93%) 992 1724 +732 (+73.79%)
dynptr_success.bpf.o test_probe_read_user_str_dynptr 689 860 +171 (+24.82%) 1016 1744 +728 (+71.65%)
iters.bpf.o checkpoint_states_deletion 1211 1216 +5 (+0.41%) 512 1280 +768 (+150.00%)
pyperf600_iter.bpf.o on_event 2591 5929 +3338 (+128.83%) 4744 11176 +6432 (+135.58%)
verifier_gotol.bpf.o gotol_large_imm 40004 40004 +0 (+0.00%) 1024 1536 +512 (+50.00%)
Total progs: 3725
Old success: 2157
New success: 2157
total_insns diff min: 0.00%
total_insns diff max: 128.83%
0 -> value: 0
value -> 0: 0
total_insns abs max old: 837,487
total_insns abs max new: 837,487
0 .. 5 %: 3710
5 .. 15 %: 6
20 .. 30 %: 6
30 .. 40 %: 2
125 .. 130 %: 1
mem_peak diff min: -27.78%
mem_peak diff max: 198.44%
mem_peak abs max old: 269,312 KiB
mem_peak abs max new: 269,312 KiB
-30 .. -20 %: 1
-5 .. 0 %: 18
0 .. 5 %: 3568
5 .. 15 %: 4
15 .. 25 %: 3
45 .. 55 %: 4
60 .. 70 %: 1
70 .. 80 %: 2
100 .. 110 %: 3
135 .. 145 %: 1
150 .. 160 %: 1
195 .. 200 %: 1
========= scx: master vs patch-set =========
Program Insns Peak memory (KiB)
------------------------ ----- ----- --------------- ----- ----- -----------------
arena_topology_node_init 2133 2395 +262 (+12.28%) 768 768 +0 (+0.00%)
chaos_dispatch 2835 2868 +33 (+1.16%) 1972 1720 -252 (-12.78%)
chaos_init 4324 5210 +886 (+20.49%) 2528 3028 +500 (+19.78%)
lavd_cpu_offline 5107 5726 +619 (+12.12%) 4188 6304 +2116 (+50.53%)
lavd_cpu_online 5107 5726 +619 (+12.12%) 4188 6304 +2116 (+50.53%)
lavd_dispatch 41775 47601 +5826 (+13.95%) 6196 29192 +22996 (+371.14%)
lavd_enqueue 20238 24188 +3950 (+19.52%) 22084 42156 +20072 (+90.89%)
lavd_init 6974 7685 +711 (+10.20%) 5428 6928 +1500 (+27.63%)
lavd_select_cpu 22138 26088 +3950 (+17.84%) 24448 43688 +19240 (+78.70%)
layered_dispatch 17847 26581 +8734 (+48.94%) 11728 28740 +17012 (+145.05%)
layered_dump 1891 2098 +207 (+10.95%) 2036 3048 +1012 (+49.71%)
layered_runnable 2606 2634 +28 (+1.07%) 748 1240 +492 (+65.78%)
p2dq_init 3691 4554 +863 (+23.38%) 2016 2528 +512 (+25.40%)
rusty_enqueue 28853 28853 +0 (+0.00%) 2072 1824 -248 (-11.97%)
rusty_init_task 31128 31128 +0 (+0.00%) 2176 2560 +384 (+17.65%)
Total progs: 148
Old success: 135
New success: 135
total_insns diff min: 0.00%
total_insns diff max: 48.94%
0 -> value: 0
value -> 0: 0
total_insns abs max old: 41,775
total_insns abs max new: 47,601
0 .. 5 %: 133
5 .. 15 %: 7
15 .. 25 %: 4
35 .. 45 %: 3
45 .. 50 %: 1
mem_peak diff min: -12.78%
mem_peak diff max: 371.14%
mem_peak abs max old: 24,448 KiB
mem_peak abs max new: 43,688 KiB
-15 .. -5 %: 2
-5 .. 0 %: 2
0 .. 5 %: 129
5 .. 15 %: 1
15 .. 25 %: 2
25 .. 35 %: 2
45 .. 55 %: 3
65 .. 75 %: 1
75 .. 85 %: 1
90 .. 100 %: 1
145 .. 155 %: 1
195 .. 205 %: 1
370 .. 375 %: 1
Changelog
---------
v1: https://lore.kernel.org/bpf/20250524191932.389444-1-eddyz87@gmail.com/
v1 -> v2:
- Rebase
- added mem_peak statistics (Alexei)
- selftests: fixed comments and removed useless r7 assignments (Yonghong)
v2: https://lore.kernel.org/bpf/20250606210352.1692944-1-eddyz87@gmail.com/
v2 -> v3:
- Rebase
Links
-----
[1] https://lore.kernel.org/bpf/20250312031344.3735498-1-eddyz87@gmail.com/
[2] commit 96a30e469c ("bpf: use common instruction history across all states")
[3] https://github.com/eddyz87/scc-test
[4] https://lore.kernel.org/bpf/20250426104634.744077-1-eddyz87@gmail.com/
[5] https://github.com/eddyz87/bpf/tree/propagate-read-and-precision-in-cfg
[6] https://github.com/eddyz87/bpf/tree/veristat-memory-accounting
[7] https://github.com/eddyz87/bpf/tree/scc-accumulate-backedges
====================
Link: https://patch.msgid.link/20250611200546.4120963-1-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The test case absent_mark_in_the_middle_state is equivalent of the
following C program:
1: r8 = bpf_get_prandom_u32();
2: r6 = -32;
3: bpf_iter_num_new(&fp[-8], 0, 10);
4: if (unlikely(bpf_get_prandom_u32()))
5: r6 = -31;
6: for (;;) {
7: if (!bpf_iter_num_next(&fp[-8]))
8: break;
9: if (unlikely(bpf_get_prandom_u32()))
10: *(u64 *)(fp + r6) = 7;
11: }
12: bpf_iter_num_destroy(&fp[-8]);
13: return 0;
W/o a fix that instructs verifier to ignore branches count for loop
entries verification proceeds as follows:
- 1-4, state is {r6=-32,fp-8=active};
- 6, checkpoint A is created with {r6=-32,fp-8=active};
- 7, checkpoint B is created with {r6=-32,fp-8=active},
push state {r6=-32,fp-8=active} from 7 to 9;
- 8,12,13, {r6=-32,fp-8=drained}, exit;
- pop state with {r6=-32,fp-8=active} from 7 to 9;
- 9, push state {r6=-32,fp-8=active} from 9 to 10;
- 6, checkpoint C is created with {r6=-32,fp-8=active};
- 7, checkpoint A is hit, no precision propagated for r6 to C;
- pop state {r6=-32,fp-8=active} from 9 to 10;
- 10, state is {r6=-31,fp-8=active}, r6 is marked as read and precise,
these marks are propagated to checkpoints A and B (but not C, as
it is not the parent of current state;
- 6, {r6=-31,fp-8=active} checkpoint C is hit, because r6 is not
marked precise for this checkpoint;
- the program is accepted, despite a possibility of unaligned u64
stack access at offset -31.
The test case absent_mark_in_the_middle_state2 is similar except the
following change:
r8 = bpf_get_prandom_u32();
r6 = -32;
bpf_iter_num_new(&fp[-8], 0, 10);
if (unlikely(bpf_get_prandom_u32())) {
r6 = -31;
+ jump_into_loop:
+ goto +0;
+ goto loop;
+ }
+ if (unlikely(bpf_get_prandom_u32()))
+ goto jump_into_loop;
+ loop:
for (;;) {
if (!bpf_iter_num_next(&fp[-8]))
break;
if (unlikely(bpf_get_prandom_u32()))
*(u64 *)(fp + r6) = 7;
}
bpf_iter_num_destroy(&fp[-8])
return 0
The goal is to check that read/precision marks are propagated to
checkpoint created at 'goto +0' that resides outside of the loop.
The test case absent_mark_in_the_middle_state3 is a bit different and
is equivalent to the C program below:
int absent_mark_in_the_middle_state3(void)
{
bpf_iter_num_new(&fp[-8], 0, 10)
loop1(-32, &fp[-8])
loop1_wrapper(&fp[-8])
bpf_iter_num_destroy(&fp[-8])
}
int loop1(num, iter)
{
while (bpf_iter_num_next(iter)) {
if (unlikely(bpf_get_prandom_u32()))
*(fp + num) = 7;
}
return 0
}
int loop1_wrapper(iter)
{
r6 = -32;
if (unlikely(bpf_get_prandom_u32()))
r6 = -31;
loop1(r6, iter);
return 0;
}
The unsafe state is reached in a similar manner, but the loop is
located inside a subprogram that is called from two locations in the
main subprogram. This detail is important for exercising
bpf_scc_visit->backedges memory management.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250611200836.4135542-11-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The previous patch switched read and precision tracking for
iterator-based loops from state-graph-based loop tracking to
control-flow-graph-based loop tracking.
This patch removes the now-unused `update_loop_entry()` and
`get_loop_entry()` functions, which were part of the state-graph-based
logic.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250611200836.4135542-9-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Current loop_entry-based exact states comparison logic does not handle
the following case:
.-> A --. Assume the states are visited in the order A, B, C.
| | | Assume that state B reaches a state equivalent to state A.
| v v At this point, state C is not processed yet, so state A
'-- B C has not received any read or precision marks from C.
As a result, these marks won't be propagated to B.
If B has incomplete marks, it is unsafe to use it in states_equal()
checks.
This commit replaces the existing logic with the following:
- Strongly connected components (SCCs) are computed over the program's
control flow graph (intraprocedurally).
- When a verifier state enters an SCC, that state is recorded as the
SCC entry point.
- When a verifier state is found equivalent to another (e.g., B to A
in the example), it is recorded as a states graph backedge.
Backedges are accumulated per SCC.
- When an SCC entry state reaches `branches == 0`, read and precision
marks are propagated through the backedges (e.g., from A to B, from
C to A, and then again from A to B).
To support nested subprogram calls, the entry state and backedge list
are associated not with the SCC itself but with an object called
`bpf_scc_callchain`. A callchain is a tuple `(callsite*, scc_id)`,
where `callsite` is the index of a call instruction for each frame
except the last.
See the comments added in `is_state_visited()` and
`compute_scc_callchain()` for more details.
Fixes: 2a0992829e ("bpf: correct loop detection for iterators convergence")
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250611200836.4135542-8-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The next patch would add some relatively heavy-weight operation to
clean_live_states(), this operation can be skipped if REG_LIVE_DONE
is set. Move the check from clean_verifier_state() to
clean_verifier_state() as a small refactoring commit.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250611200836.4135542-7-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add an out parameter to `propagate_liveness()` to record whether any
new liveness bits were set during its execution.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250611200836.4135542-6-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add an out parameter to `propagate_precision()` to record whether any
new precision bits were set during its execution.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250611200836.4135542-5-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Allow `mark_chain_precision()` to run from an arbitrary starting state
by replacing direct references to `env->cur_state` with a parameter.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250611200836.4135542-4-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
A function to return IP for a given frame in a call stack of a state.
Will be used by a next patch.
The `state->insn_idx = env->insn_idx;` assignment in the do_check()
allows to use frame_insn_idx with env->cur_state.
At the moment bpf_verifier_state->insn_idx is set when new cached
state is added in is_state_visited() and accessed only in the contexts
when the state is already in the cache. Hence this assignment does not
change verifier behaviour.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250611200836.4135542-3-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This reverts commit 96a30e469c.
Next patches in the series modify propagate_precision() to allow
arbitrary starting state. Precision propagation requires access to
jump history, and arbitrary states represent history not belonging to
`env->cur_state`.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250611200836.4135542-1-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add methods to FwNode for reading several firmware property types like
strings, integers and arrays.
Most types are read with the generic `property_read` method. There are
two exceptions:
* `property_read_bool` cannot fail, so the fallible function signature
of `property_read` would not make sense for reading booleans.
* `property_read_array_vec` can fail because of a dynamic memory
allocation. This error must be handled separately, leading to a
different function signature than `property_read`.
The traits `Property` and `PropertyInt` drive the generic behavior
of `property_read`. `PropertyInt` is necessary to associate
specific integer types with the C functions to read them. While
there is a C function to read integers of generic sizes called
`fwnode_property_read_int_array`, it was preferred not to make this
public.
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Co-developed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Remo Senekowitsch <remo@buenzli.dev>
Link: https://lore.kernel.org/r/20250611102908.212514-7-remo@buenzli.dev
[ Properly include kernel::device::private::Sealed; add explicit type
annotations for core::mem::transmute(). - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
This abstraction is a way to force users to specify whether a property
is supposed to be required or not. This allows us to move error
logging of missing required properties into core, preventing a lot of
boilerplate in drivers.
It will be used by upcoming methods for reading device properties.
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Signed-off-by: Remo Senekowitsch <remo@buenzli.dev>
Link: https://lore.kernel.org/r/20250611102908.212514-6-remo@buenzli.dev
[ Use prelude::* to avoid build failure; move PropertyGuard below Display
impl of FwNode. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Add two new public methods `display_name` and `display_path` to
`FwNode`. They can be used by driver authors for logging purposes. In
addition, they will be used by core property abstractions for automatic
logging, for example when a driver attempts to read a required but
missing property.
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Signed-off-by: Remo Senekowitsch <remo@buenzli.dev>
Link: https://lore.kernel.org/r/20250611102908.212514-5-remo@buenzli.dev
[ Remove #[expect(dead_code)] from FwNode::from_raw(). - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
The new FwNode abstraction will be used for accessing all device
properties.
It would be possible to duplicate the methods on the device itself, but
since some of the methods on Device would have different type sigatures
as the ones on FwNode, this would only lead to inconsistency and
confusion. For this reason, property_present is removed from Device and
existing users are updated.
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Remo Senekowitsch <remo@buenzli.dev>
Link: https://lore.kernel.org/r/20250611102908.212514-4-remo@buenzli.dev
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Subsequent patches will add methods for reading properties to FwNode.
The first step to accessing these methods will be to access the "root"
FwNode of a Device.
Add the method `fwnode` to `Device`.
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Signed-off-by: Remo Senekowitsch <remo@buenzli.dev>
Link: https://lore.kernel.org/r/20250611102908.212514-3-remo@buenzli.dev
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
When the GuC fails to load we declare the device wedged. However, the
very first GuC load attempt on GT0 (from xe_gt_init_hwconfig) is done
before the GT1 GuC objects are initialized, so things go bad when the
wedge code attempts to cleanup GT1. To fix this, check the initialization
status in the functions called during wedge.
Fixes: 7dbe8af13c ("drm/xe: Wedge the entire device")
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Jonathan Cavitt <jonathan.cavitt@intel.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Cc: Zhanjun Dong <zhanjun.dong@intel.com>
Cc: stable@vger.kernel.org # v6.12+: 1e1981b16b: drm/xe: Fix taking invalid lock on wedge
Cc: stable@vger.kernel.org # v6.12+
Reviewed-by: Jonathan Cavitt <jonathan.cavitt@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://lore.kernel.org/r/20250611214453.1159846-2-daniele.ceraolospurio@intel.com
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Accessing device properties is currently done via methods on `Device`
itself, using bindings to device_property_* functions. This is
sufficient for the existing method property_present. However, it's not
sufficient for other device properties we want to access. For example,
iterating over child nodes of a device will yield a fwnode_handle.
That's not a device, so it wouldn't be possible to read the properties
of that child node. Thus, we need an abstraction over fwnode_handle and
methods for reading its properties.
Add a struct FwNode which abstracts over the C struct fwnode_handle.
Implement its reference counting analogous to other Rust abstractions
over reference-counted C structs.
Subsequent patches will add functionality to access FwNode and read
properties with it.
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Signed-off-by: Remo Senekowitsch <remo@buenzli.dev>
Link: https://lore.kernel.org/r/20250611102908.212514-2-remo@buenzli.dev
[ Add temporary #[expect(dead_code)] to avoid a warning. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
I must have lost this rebasing things during the merge window, I know I
got it at some point but it's not here now. Without this I get warnings
along the lines of
include/linux/fs.h:3975:15: warning: label followed by a declaration is a C23 extension [-Wc23-extensions]
3975 | if (unlikely(get_user(c, path)))
| ^
arch/riscv/include/asm/uaccess.h:274:3: note: expanded from macro 'get_user'
274 | __get_user((x), __p) : \
| ^
arch/riscv/include/asm/uaccess.h:244:2: note: expanded from macro '__get_user'
244 | __get_user_error(__gu_val, __gu_ptr, __gu_err); \
| ^
arch/riscv/include/asm/uaccess.h:207:2: note: expanded from macro '__get_user_error'
207 | __ge LD [M] net/802/psnap.ko
t_user_nocheck(x, ptr, __gu_failed); \
| ^
arch/riscv/include/asm/uaccess.h:196:3: note: expanded from macro '__get_user_nocheck'
196 | __get_user_8((x), __gu_ptr, label); \
| ^
arch/riscv/include/asm/uaccess.h:130:2: note: expanded from macro '__get_user_8'
130 | u32 __user *__ptr = (u32 __user *)(ptr); \
| ^
Link: https://lore.kernel.org/r/20250610213058.24852-1-palmer@dabbelt.com
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Cc: stable@vger.kernel.org
Fixes: f6bff7827a ("riscv: uaccess: use 'asm_goto_output' for get_user()")
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Fix for __GENMASK() and __GENMASK_ULL() in UAPI.
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Merge tag 'bitmap-for-6.16-rc2' of https://github.com/norov/linux
Pull bitmap fix from Yury Norov:
"Fix for __GENMASK() and __GENMASK_ULL() in UAPI"
* tag 'bitmap-for-6.16-rc2' of https://github.com/norov/linux:
uapi: bitops: use UAPI-safe variant of BITS_PER_LONG again
When running the raid6 user-space test program on RISC-V QEMU, there's a
segmentation fault which seems caused by accessing a NULL pointer,
which is the pointer variable p/q in raid6_rvv*_gen/xor_syndrome_real(),
p/q should have been equal to dptr[x], but when I use GDB command to
see its value, which was 0x10 like below:
"
Program received signal SIGSEGV, Segmentation fault.
0x0000000000011062 in raid6_rvv2_xor_syndrome_real (disks=<optimized out>, start=0, stop=<optimized out>, bytes=4096, ptrs=<optimized out>) at rvv.c:386
(gdb) p p
$1 = (u8 *) 0x10 <error: Cannot access memory at address 0x10>
"
The issue was found to be related with:
1) Compile optimization
There's no segmentation fault if compiling the raid6test program with
the optimization flag -O0.
2) The RISC-V vector command vsetvli
If not used t0 as the first parameter in vsetvli, there's no
segmentation fault either.
This patch selects the 2nd solution to fix the issue.
[Palmer: The actual issue here is a missing clobber in the vsetvli code.
It's a little tricky: we've already probed for VLENB so we don't need to
look at the output register, we just need to have an X register in the
instruction as that's the form required to actually set VL. Thus we
clobber a register, and without describing that we end up breaking
compilers.]
Fixes: 6093faaf95 ("raid6: Add RISC-V SIMD syndrome and recovery calculations")
Signed-off-by: Chunyan Zhang <zhangchunyan@iscas.ac.cn>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20250610101234.1100660-3-zhangchunyan@iscas.ac.cn
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
riscv fixes for 6.16-rc1
- A fix for the newly introduced getrandom vdso where clang optimizes
away a register variable which is both an input and an output
parameter
- A fix for theadvector where we did not save all the vector registers,
only a few of them
* tag 'riscv-fixes-6.16-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/alexghiti/linux:
RISC-V: vDSO: Correct inline assembly constraints in the getrandom syscall wrapper
riscv: vector: Fix context save/restore with xtheadvector
As recently pointed out by Thomas, if a register is forced for two
different register variables, among them one is used as "+" (both input
and output) and another is only used as input, Clang would treat the
conflicting input parameters as undefined behaviour and optimize away
the argument assignment.
Instead use "=r" (only output) for the output parameter and "r" (only
input) for the input parameter.
While the example from the GCC documentation uses "0" for the input
parameter, this is not necessary as confirmed by the GCC developers and "r"
matches what the other architectures' vDSO implementations are using.
[ alex: Update log to match v2 (Thomas) ]
Link: https://lore.kernel.org/all/20250603-loongarch-vdso-syscall-v1-1-6d12d6dfbdd0@linutronix.de/
Link: https://gcc.gnu.org/onlinedocs/gcc-15.1.0/gcc/Local-Register-Variables.html
Link: https://gcc.gnu.org/pipermail/gcc-help/2025-June/144266.html
Cc: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
Reviewed-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Fixes: ee0d03053e ("RISC-V: vDSO: Wire up getrandom() vDSO")
Link: https://lore.kernel.org/r/20250606092443.73650-2-xry111@xry111.site
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Previously only v0-v7 were correctly saved/restored,
and the context of v8-v31 are damanged.
Correctly save/restore v8-v31 to avoid breaking userspace.
Fixes: d863910eab ("riscv: vector: Support xtheadvector save/restore")
Cc: stable@vger.kernel.org
Signed-off-by: Han Gao <rabenda.cn@gmail.com>
Tested-by: Xiongchuan Tan <tanxiongchuan@isrc.iscas.ac.cn>
Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>
Reviewed-by: Yanteng Si <si.yanteng@linux.dev>
Reviewed-by: Andy Chiu <andybnac@gmail.com>
Link: https://lore.kernel.org/r/9b9eb2337f3d5336ce813721f8ebea51e0b2b553.1747994822.git.rabenda.cn@gmail.com
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Make the logic easier to follow:
- Remove the final return statement, which is never reached, and move the
actual walk-terminating return statement out of the do-while loop.
- Remove the else-clause to reduce indentation. If a non-lonely group is
encountered during the walk, the loop is immediately terminated with a
return statement anyway; no need for an else.
Signed-off-by: Petr Tesarik <ptesarik@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/all/20250606124818.455560-1-ptesarik@suse.com
Introduce `dphy_conf_clks` and `dphy_mode_clk_check` callbacks in
`rzg2l_mipi_dsi_hw_info` to configure the VCLK and validate
supported display modes.
On the RZ/V2H(P) SoC, the DSI PLL dividers need to be as accurate as
possible. To ensure compatibility with both RZ/G2L and RZ/V2H(P) SoCs,
function pointers are introduced.
Modify `rzg2l_mipi_dsi_startup()` to use `dphy_conf_clks` for clock
configuration and `rzg2l_mipi_dsi_bridge_mode_valid()` to invoke
`dphy_mode_clk_check` for mode validation.
This change ensures proper operation across different SoC variants
by allowing fine-grained control over clock configuration and mode
validation.
Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/r/20250609225630.502888-10-prabhakar.mahadev-lad.rj@bp.renesas.com
Introduce the `dphy_late_init` callback in `rzg2l_mipi_dsi_hw_info` to
allow additional D-PHY register configurations after enabling data and
clock lanes. This is required for the RZ/V2H(P) SoC but not for the
RZ/G2L SoC.
Modify `rzg2l_mipi_dsi_startup()` to invoke `dphy_late_init` if defined,
ensuring SoC-specific initialization is performed only when necessary.
This change prepares for RZ/V2H(P) SoC support while maintaining
compatibility with existing platforms.
Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/r/20250609225630.502888-9-prabhakar.mahadev-lad.rj@bp.renesas.com
Introduce the `RZ_MIPI_DSI_FEATURE_16BPP` flag in `rzg2l_mipi_dsi_hw_info`
to indicate support for 16BPP pixel formats. The RZ/V2H(P) SoC supports
16BPP, whereas this feature is missing on the RZ/G2L SoC.
Update the `mipi_dsi_host_attach()` function to check this flag before
allowing 16BPP formats. If the SoC does not support 16BPP, return an error
to prevent incorrect format selection.
This change enables finer-grained format support control for different
SoC variants.
Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/r/20250609225630.502888-8-prabhakar.mahadev-lad.rj@bp.renesas.com
Pass the HSFREQ in milli-Hz to the `dphy_init()` callback to improve
precision, especially for the RZ/V2H(P) SoC, where PLL dividers require
high accuracy.
These changes prepare the driver for upcoming RZ/V2H(P) SoC support.
Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/r/20250609225630.502888-7-prabhakar.mahadev-lad.rj@bp.renesas.com
In preparation for adding support for the Renesas RZ/V2H(P) SoC, make the
"rst" reset control optional in the MIPI DSI driver. The RZ/V2H(P) SoC
does not provide this reset line, and attempting to acquire it using the
mandatory API causes probe failure.
Switching to devm_reset_control_get_optional_exclusive() ensures
compatibility with both SoCs that provide this reset line and those that
do not, such as RZ/V2H(P).
Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/r/20250609225630.502888-6-prabhakar.mahadev-lad.rj@bp.renesas.com
n preparation for adding support for the Renesas RZ/V2H(P) SoC, this patch
introduces a mechanism to pass SoC-specific information via OF data in the
DSI driver. This enables the driver to adapt dynamically to various
SoC-specific requirements without hardcoding configurations.
The MIPI DSI interface on the RZ/V2H(P) SoC is nearly identical to the one
on the RZ/G2L SoC. While the LINK registers are shared between the two
SoCs, the D-PHY registers differ. Also the VCLK range differs on both these
SoCs. To accommodate these differences `struct rzg2l_mipi_dsi_hw_info` is
introduced and as now passed as OF data.
These changes lay the groundwork for the upcoming RZ/V2H(P) SoC support by
allowing SoC-specific data to be passed through OF.
Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/r/20250609225630.502888-5-prabhakar.mahadev-lad.rj@bp.renesas.com
Update the RZ/G2L MIPI DSI driver to calculate HSFREQ using the actual
VCLK rate instead of the mode clock. The relationship between HSCLK and
VCLK is:
vclk * bpp <= hsclk * 8 * lanes
Retrieve the VCLK rate using `clk_get_rate(dsi->vclk)`, ensuring that
HSFREQ accurately reflects the clock rate set in hardware, leading to
better precision in data transmission.
Additionally, use `DIV_ROUND_CLOSEST_ULL` for a more precise division
when computing `hsfreq`. Also, update unit conversions to use correct
scaling factors for better clarity and correctness.
Since `clk_get_rate()` returns the clock rate in Hz, update the HSFREQ
threshold comparisons to use Hz instead of kHz to ensure correct behavior.
Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/r/20250609225630.502888-4-prabhakar.mahadev-lad.rj@bp.renesas.com
Simplify the high-speed clock frequency (HSFREQ) calculation by removing
the redundant multiplication and division by 8. The updated equation:
hsfreq = mode->clock * bpp / dsi->lanes;
produces the same result while improving readability and clarity.
Additionally, update the comment to clarify the relationship between HS
clock bit frequency, HS byte clock frequency, and HSFREQ.
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/r/20250609225630.502888-3-prabhakar.mahadev-lad.rj@bp.renesas.com
The VCLK range for Renesas RZ/G2L SoC is 5.803 MHz to 148.5 MHz. Add a
minimum clock check in the mode_valid callback to ensure that the clock
value does not fall below the valid range.
Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/r/20250609225630.502888-2-prabhakar.mahadev-lad.rj@bp.renesas.com
Currently, cached directory contents were not reused across subsequent
'ls' operations because the cache validity check relied on comparing
the ctx pointer, which changes with each readdir invocation. As a
result, the cached dir entries was not marked as valid and the cache was
not utilized for subsequent 'ls' operations.
This change uses the file pointer, which remains consistent across all
readdir calls for a given directory instance, to associate and validate
the cache. As a result, cached directory contents can now be
correctly reused, improving performance for repeated directory listings.
Performance gains with local windows SMB server:
Without the patch and default actimeo=1:
1000 directory enumeration operations on dir with 10k files took 135.0s
With this patch and actimeo=0:
1000 directory enumeration operations on dir with 10k files took just 5.1s
Signed-off-by: Bharath SM <bharathsm@microsoft.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
The thread sanitizer makes the stack usage explode from extra variable
spills in dispc_runtime_resume:
drivers/gpu/drm/omapdrm/dss/dispc.c:4735:27: error: stack frame size (1824) exceeds limit (1280) in 'dispc_runtime_resume' [-Werror,-Wframe-larger-than]
I could not figure out what exactly is going on here, but I see that
whenever dispc_restore_context() is not inlined, that function
and its caller shrink below 900 bytes combined of stack usage.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20250610092737.2641862-1-arnd@kernel.org
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
No idea why, but without this GuC context switches randomly fail when
running IGTs in a loop. Need to follow up why this fixes the
aforementioned issue but can live with a stable driver for now.
Fixes: 617d824c53 ("drm/xe: Add WA BB to capture active context utilization")
Cc: stable@vger.kernel.org
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Tested-by: Shuicheng Lin <shuicheng.lin@intel.com>
Link: https://lore.kernel.org/r/20250612031925.4009701-1-matthew.brost@intel.com
Reading DPCD registers has side-effects and some of these can cause a
problem for instance during link training. Based on this it's better to
avoid the probing quirk done before each DPCD register read, limiting
this to the monitor which requires it. The only known problematic
monitor is an external SST sink, so keep the quirk disabled always for
eDP and MST sinks. Reenable the quirk after a hotplug event and after
resuming from a power state without hotplug support, until the
subsequent EDID based detection.
v2: Add a helper for determining the need/setting the probing. (Jani)
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Reviewed-by: Mika Kahola <mika.kahola@intel.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://lore.kernel.org/r/20250609125556.109538-2-imre.deak@intel.com
