Merge drm/drm-fixes into drm-misc-fixes

Updating drm-misc-fixes to the state of v6.17-rc1. Begins a new release
cycle.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Merge tag 'bpf-next-6.17' into loongarch-next

LoongArch architecture changes for 6.17 have many bpf features such as
trampoline, so merge 'bpf-next-6.17' to create a base to make bpf work
well.

Merge tag 'bpf-next-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Pull bpf updates from Alexei Starovoitov:

- Remove usermode driver (UMD) framework (Thomas Weißschuh)

- In

Merge tag 'bpf-next-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Pull bpf updates from Alexei Starovoitov:

- Remove usermode driver (UMD) framework (Thomas Weißschuh)

- Introduce Strongly Connected Component (SCC) in the verifier to
detect loops and refine register liveness (Eduard Zingerman)

- Allow 'void *' cast using bpf_rdonly_cast() and corresponding
'__arg_untrusted' for global function parameters (Eduard Zingerman)

- Improve precision for BPF_ADD and BPF_SUB operations in the verifier
(Harishankar Vishwanathan)

- Teach the verifier that constant pointer to a map cannot be NULL
(Ihor Solodrai)

- Introduce BPF streams for error reporting of various conditions
detected by BPF runtime (Kumar Kartikeya Dwivedi)

- Teach the verifier to insert runtime speculation barrier (lfence on
x86) to mitigate speculative execution instead of rejecting the
programs (Luis Gerhorst)

- Various improvements for 'veristat' (Mykyta Yatsenko)

- For CONFIG_DEBUG_KERNEL config warn on internal verifier errors to
improve bug detection by syzbot (Paul Chaignon)

- Support BPF private stack on arm64 (Puranjay Mohan)

- Introduce bpf_cgroup_read_xattr() kfunc to read xattr of cgroup's
node (Song Liu)

- Introduce kfuncs for read-only string opreations (Viktor Malik)

- Implement show_fdinfo() for bpf_links (Tao Chen)

- Reduce verifier's stack consumption (Yonghong Song)

- Implement mprog API for cgroup-bpf programs (Yonghong Song)

* tag 'bpf-next-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (192 commits)
selftests/bpf: Migrate fexit_noreturns case into tracing_failure test suite
selftests/bpf: Add selftest for attaching tracing programs to functions in deny list
bpf: Add log for attaching tracing programs to functions in deny list
bpf: Show precise rejected function when attaching fexit/fmod_ret to __noreturn functions
bpf: Fix various typos in verifier.c comments
bpf: Add third round of bounds deduction
selftests/bpf: Test invariants on JSLT crossing sign
selftests/bpf: Test cross-sign 64bits range refinement
selftests/bpf: Update reg_bound range refinement logic
bpf: Improve bounds when s64 crosses sign boundary
bpf: Simplify bounds refinement from s32
selftests/bpf: Enable private stack tests for arm64
bpf, arm64: JIT support for private stack
bpf: Move bpf_jit_get_prog_name() to core.c
bpf, arm64: Fix fp initialization for exception boundary
umd: Remove usermode driver framework
bpf/preload: Don't select USERMODE_DRIVER
selftests/bpf: Fix test dynptr/test_dynptr_memset_xdp_chunks failure
selftests/bpf: Fix test dynptr/test_dynptr_copy_xdp failure
selftests/bpf: Increase xdp data size for arm64 64K page size
...

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Merge branch 'bpf-add-kfuncs-for-read-only-string-operations'

Viktor Malik says:

====================
bpf: Add kfuncs for read-only string operations

String operations are commonly used in program

Merge branch 'bpf-add-kfuncs-for-read-only-string-operations'

Viktor Malik says:

====================
bpf: Add kfuncs for read-only string operations

String operations are commonly used in programming and BPF programs are
no exception. Since it is cumbersome to reimplement them over and over,
this series introduce kfuncs which provide the most common operations.
For now, we only limit ourselves to functions which do not copy memory
since these usually introduce undefined behaviour in case the
source/destination buffers overlap which would have to be prevented by
the verifier.

The kernel already contains implementations for all of these, however,
it is not possible to use them from BPF context. The main reason is that
the verifier is not able to check that it is safe to access the entire
string and that the string is null-terminated and the function won't
loop forever. Therefore, the operations are open-coded using
__get_kernel_nofault instead of plain dereference and bounded to at most
XATTR_SIZE_MAX characters to make them safe. That allows to skip all the
verfier checks for the passed-in strings as safety is ensured
dynamically.

All of the proposed functions return integers, even those that normally
(in the kernel or libc) return pointers into the strings. The reason is
that since the strings are generally treated as unsafe, the pointers
couldn't be dereferenced anyways. So, instead, we return an index to the
string and let user decide what to do with it. The integer APIs also
allow to return various error codes when unexpected situations happen
while processing the strings.

The series include both positive and negative tests using the kfuncs.

Changelog
---------

Changes in v8:
- Return -ENOENT (instead of -1) when "item not found" for relevant
functions (Alexei).
- Small adjustments of the string algorithms (Andrii).
- Adapt comments to kernel style (Alexei).

Changes in v7:
- Disable negative tests passing NULL and 0x1 to kfuncs on s390 as they
aren't relevant (see comment in string_kfuncs_failure1.c for details).

Changes in v6:
- Improve the third patch which allows to use macros in __retval in
selftests. The previous solution broke several tests.

Changes in v5:
- Make all kfuncs return integers (Andrii).
- Return -ERANGE when passing non-kernel pointers on arches with
non-overlapping address spaces (Alexei).
- Implement "unbounded" variants using the bounded ones (Andrii).
- Add more negative test cases.

Changes in v4 (all suggested by Andrii):
- Open-code all the kfuncs, not just the unbounded variants.
- Introduce `pagefault` lock guard to simplify the implementation
- Return appropriate error codes (-E2BIG and -EFAULT) on failures
- Const-ify all arguments and return values
- Add negative test-cases

Changes in v3:
- Open-code unbounded variants with __get_kernel_nofault instead of
dereference (suggested by Alexei).
- Use the __sz suffix for size parameters in bounded variants (suggested
by Eduard and Alexei).
- Make tests more compact (suggested by Eduard).
- Add benchmark.
====================

Link: https://patch.msgid.link/cover.1750917800.git.vmalik@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

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selftests/bpf: Add tests for string kfuncs

Add both positive and negative tests cases using string kfuncs added in
the previous patches.

Positive tests check that the functions work as expected.

N

selftests/bpf: Add tests for string kfuncs

Add both positive and negative tests cases using string kfuncs added in
the previous patches.

Positive tests check that the functions work as expected.

Negative tests pass various incorrect strings to the kfuncs and check
for the expected error codes:
-E2BIG when passing too long strings
-EFAULT when trying to read inaccessible kernel memory
-ERANGE when passing userspace pointers on arches with non-overlapping
address spaces

A majority of the tests use the RUN_TESTS helper which executes BPF
programs with BPF_PROG_TEST_RUN and check for the expected return value.
An exception to this are tests for long strings as we need to memset the
long string from userspace (at least I haven't found an ergonomic way to
memset it from a BPF program), which cannot be done using the RUN_TESTS
infrastructure.

Suggested-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Viktor Malik <vmalik@redhat.com>
Link: https://lore.kernel.org/r/090451a2e60c9ae1dceb4d1bfafa3479db5c7481.1750917800.git.vmalik@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

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