Commit Graph

134 Commits

Author SHA1 Message Date
Xu Kuohai
d9ef13f727 bpf: Pass bpf_verifier_env to JIT
Pass bpf_verifier_env to bpf_int_jit_compile(). The follow-up patch will
use env->insn_aux_data in the JIT stage to detect indirect jump targets.

Since bpf_prog_select_runtime() can be called by cbpf and lib/test_bpf.c
code without verifier, introduce helper __bpf_prog_select_runtime()
to accept the env parameter.

Remove the call to bpf_prog_select_runtime() in bpf_prog_load(), and
switch to call __bpf_prog_select_runtime() in the verifier, with env
variable passed. The original bpf_prog_select_runtime() is preserved for
cbpf and lib/test_bpf.c, where env is NULL.

Now all constants blinding calls are moved into the verifier, except
the cbpf and lib/test_bpf.c cases. The instructions arrays are adjusted
by bpf_patch_insn_data() function for normal cases, so there is no need
to call adjust_insn_arrays() in bpf_jit_blind_constants(). Remove it.

Reviewed-by: Anton Protopopov <a.s.protopopov@gmail.com> # v8
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> # v12
Acked-by: Hengqi Chen <hengqi.chen@gmail.com> # v14
Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
Link: https://lore.kernel.org/r/20260416064341.151802-3-xukuohai@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-16 07:03:40 -07:00
Xu Kuohai
d3e945223e bpf: Move constants blinding out of arch-specific JITs
During the JIT stage, constants blinding rewrites instructions but only
rewrites the private instruction copy of the JITed subprog, leaving the
global env->prog->insnsi and env->insn_aux_data untouched. This causes a
mismatch between subprog instructions and the global state, making it
difficult to use the global data in the JIT.

To avoid this mismatch, and given that all arch-specific JITs already
support constants blinding, move it to the generic verifier code, and
switch to rewrite the global env->prog->insnsi with the global states
adjusted, as other rewrites in the verifier do.

This removes the constants blinding calls in each JIT, which are largely
duplicated code across architectures.

Since constants blinding is only required for JIT, and there are two
JIT entry functions, jit_subprogs() for BPF programs with multiple
subprogs and bpf_prog_select_runtime() for programs with no subprogs,
move the constants blinding invocation into these two functions.

In the verifier path, bpf_patch_insn_data() is used to keep global
verifier auxiliary data in sync with patched instructions. A key
question is whether this global auxiliary data should be restored
on the failure path.

Besides instructions, bpf_patch_insn_data() adjusts:
  - prog->aux->poke_tab
  - env->insn_array_maps
  - env->subprog_info
  - env->insn_aux_data

For prog->aux->poke_tab, it is only used by JIT or only meaningful after
JIT succeeds, so it does not need to be restored on the failure path.

For env->insn_array_maps, when JIT fails, programs using insn arrays
are rejected by bpf_insn_array_ready() due to missing JIT addresses.
Hence, env->insn_array_maps is only meaningful for JIT and does not need
to be restored.

For subprog_info, if jit_subprogs fails and CONFIG_BPF_JIT_ALWAYS_ON
is not enabled, kernel falls back to interpreter. In this case,
env->subprog_info is used to determine subprogram stack depth. So it
must be restored on failure.

For env->insn_aux_data, it is freed by clear_insn_aux_data() at the
end of bpf_check(). Before freeing, clear_insn_aux_data() loops over
env->insn_aux_data to release jump targets recorded in it. The loop
uses env->prog->len as the array length, but this length no longer
matches the actual size of the adjusted env->insn_aux_data array after
constants blinding.

To address it, a simple approach is to keep insn_aux_data as adjusted
after failure, since it will be freed shortly, and record its actual size
for the loop in clear_insn_aux_data(). But since clear_insn_aux_data()
uses the same index to loop over both env->prog->insnsi and env->insn_aux_data,
this approach results in incorrect index for the insnsi array. So an
alternative approach is adopted: clone the original env->insn_aux_data
before blinding and restore it after failure, similar to env->prog.

For classic BPF programs, constants blinding works as before since it
is still invoked from bpf_prog_select_runtime().

Reviewed-by: Anton Protopopov <a.s.protopopov@gmail.com> # v8
Reviewed-by: Hari Bathini <hbathini@linux.ibm.com> # powerpc jit
Reviewed-by: Pu Lehui <pulehui@huawei.com> # riscv jit
Acked-by: Hengqi Chen <hengqi.chen@gmail.com> # loongarch jit
Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
Link: https://lore.kernel.org/r/20260416064341.151802-2-xukuohai@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-16 07:03:40 -07:00
Puranjay Mohan
46ee1342b8 bpf, riscv: Remove redundant bpf_flush_icache() after pack allocator finalize
bpf_flush_icache() calls flush_icache_range() to clean the data cache
and invalidate the instruction cache for the JITed code region. However,
since commit 48a8f78c50 ("bpf, riscv: use prog pack allocator in the
BPF JIT"), this flush is redundant.

bpf_jit_binary_pack_finalize() copies the JITed instructions to the ROX
region via bpf_arch_text_copy() -> patch_text_nosync(), and
patch_text_nosync() already calls flush_icache_range() on the written
range. The subsequent bpf_flush_icache() repeats the same cache
maintenance on an overlapping range.

Remove the redundant bpf_flush_icache() call and its now-unused
definition.

Fixes: 48a8f78c50 ("bpf, riscv: use prog pack allocator in the BPF JIT")
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
Reviewed-by: Pu Lehui <pulehui@huawei.com>
Tested-by: Paul Chaignon <paul.chaignon@gmail.com>
Link: https://lore.kernel.org/r/20260413191111.3426023-3-puranjay@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-15 12:09:46 -07:00
Linus Torvalds
bf4afc53b7 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument
This was done entirely with mindless brute force, using

    git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21 17:09:51 -08:00
Kees Cook
69050f8d6d treewide: Replace kmalloc with kmalloc_obj for non-scalar types
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-21 01:02:28 -08:00
Menglong Dong
35b3515be0 bpf, riscv: add fsession support for trampolines
Implement BPF_TRACE_FSESSION support in the RISC-V trampoline JIT. The
logic here is similar to what we did in x86_64.

In order to simply the logic, we factor out the function invoke_bpf() for
fentry and fexit.

Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn>
Tested-by: Björn Töpel <bjorn@kernel.org>
Acked-by: Björn Töpel <bjorn@kernel.org>
Link: https://lore.kernel.org/r/20260208053311.698352-3-dongml2@chinatelecom.cn
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-02-13 14:14:27 -08:00
Menglong Dong
93fd420d71 bpf, riscv: introduce emit_store_stack_imm64() for trampoline
Introduce a helper to store 64-bit immediate on the trampoline stack with
a help of a register.

Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn>
Tested-by: Björn Töpel <bjorn@kernel.org>
Acked-by: Björn Töpel <bjorn@kernel.org>
Link: https://lore.kernel.org/r/20260208053311.698352-2-dongml2@chinatelecom.cn
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-02-13 14:14:27 -08:00
Menglong Dong
8f3e00af8e riscv, bpf: Fix incorrect usage of BPF_TRAMP_F_ORIG_STACK
The usage of BPF_TRAMP_F_ORIG_STACK in __arch_prepare_bpf_trampoline() is
wrong, and it should be BPF_TRAMP_F_CALL_ORIG, which caused crash as
Andreas reported:

  Insufficient stack space to handle exception!
  Task stack:     [0xff20000000010000..0xff20000000014000]
  Overflow stack: [0xff600000ffdad070..0xff600000ffdae070]
  CPU: 1 UID: 0 PID: 1 Comm: systemd Not tainted 6.18.0-rc5+ #15 PREEMPT(voluntary)
  Hardware name: riscv-virtio qemu/qemu, BIOS 2025.10 10/01/2025
  epc : copy_from_kernel_nofault+0xa/0x198
   ra : bpf_probe_read_kernel+0x20/0x60
  epc : ffffffff802b732a ra : ffffffff801e6070 sp : ff2000000000ffe0
   gp : ffffffff82262ed0 tp : 0000000000000000 t0 : ffffffff80022320
   t1 : ffffffff801e6056 t2 : 0000000000000000 s0 : ff20000000010040
   s1 : 0000000000000008 a0 : ff20000000010050 a1 : ff60000083b3d320
   a2 : 0000000000000008 a3 : 0000000000000097 a4 : 0000000000000000
   a5 : 0000000000000000 a6 : 0000000000000021 a7 : 0000000000000003
   s2 : ff20000000010050 s3 : ff6000008459fc18 s4 : ff60000083b3d340
   s5 : ff20000000010060 s6 : 0000000000000000 s7 : ff20000000013aa8
   s8 : 0000000000000000 s9 : 0000000000008000 s10: 000000000058dcb0
   s11: 000000000058dca7 t3 : 000000006925116d t4 : ff6000008090f026
   t5 : 00007fff9b0cbaa8 t6 : 0000000000000016
  status: 0000000200000120 badaddr: 0000000000000000 cause: 8000000000000005
  Kernel panic - not syncing: Kernel stack overflow
  CPU: 1 UID: 0 PID: 1 Comm: systemd Not tainted 6.18.0-rc5+ #15 PREEMPT(voluntary)
  Hardware name: riscv-virtio qemu/qemu, BIOS 2025.10 10/01/2025
  Call Trace:
  [<ffffffff8001a1f8>] dump_backtrace+0x28/0x38
  [<ffffffff80002502>] show_stack+0x3a/0x50
  [<ffffffff800122be>] dump_stack_lvl+0x56/0x80
  [<ffffffff80012300>] dump_stack+0x18/0x22
  [<ffffffff80002abe>] vpanic+0xf6/0x328
  [<ffffffff80002d2e>] panic+0x3e/0x40
  [<ffffffff80019ef0>] handle_bad_stack+0x98/0xa0
  [<ffffffff801e6070>] bpf_probe_read_kernel+0x20/0x60

Just fix it.

Fixes: 47c9214dcb ("bpf: fix the usage of BPF_TRAMP_F_SKIP_FRAME")
Link: https://lore.kernel.org/bpf/20251219142948.204312-1-dongml2@chinatelecom.cn
Closes: https://lore.kernel.org/bpf/874ipnkfvt.fsf@igel.home/
Reported-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-01-06 11:40:48 -08:00
Menglong Dong
ae4a3160d1 bpf: specify the old and new poke_type for bpf_arch_text_poke
In the origin logic, the bpf_arch_text_poke() assume that the old and new
instructions have the same opcode. However, they can have different opcode
if we want to replace a "call" insn with a "jmp" insn.

Therefore, add the new function parameter "old_t" along with the "new_t",
which are used to indicate the old and new poke type. Meanwhile, adjust
the implement of bpf_arch_text_poke() for all the archs.

"BPF_MOD_NOP" is added to make the code more readable. In
bpf_arch_text_poke(), we still check if the new and old address is NULL to
determine if nop insn should be used, which I think is more safe.

Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn>
Link: https://lore.kernel.org/r/20251118123639.688444-6-dongml2@chinatelecom.cn
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-11-24 09:47:03 -08:00
Menglong Dong
47c9214dcb bpf: fix the usage of BPF_TRAMP_F_SKIP_FRAME
Some places calculate the origin_call by checking if
BPF_TRAMP_F_SKIP_FRAME is set. However, it should use
BPF_TRAMP_F_ORIG_STACK for this propose. Just fix them.

Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/r/20251118123639.688444-4-dongml2@chinatelecom.cn
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-11-24 09:47:03 -08:00
Linus Torvalds
ae28ed4578 bpf-next-6.18
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Merge tag 'bpf-next-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Pull bpf updates from Alexei Starovoitov:

 - Support pulling non-linear xdp data with bpf_xdp_pull_data() kfunc
   (Amery Hung)

   Applied as a stable branch in bpf-next and net-next trees.

 - Support reading skb metadata via bpf_dynptr (Jakub Sitnicki)

   Also a stable branch in bpf-next and net-next trees.

 - Enforce expected_attach_type for tailcall compatibility (Daniel
   Borkmann)

 - Replace path-sensitive with path-insensitive live stack analysis in
   the verifier (Eduard Zingerman)

   This is a significant change in the verification logic. More details,
   motivation, long term plans are in the cover letter/merge commit.

 - Support signed BPF programs (KP Singh)

   This is another major feature that took years to materialize.

   Algorithm details are in the cover letter/marge commit

 - Add support for may_goto instruction to s390 JIT (Ilya Leoshkevich)

 - Add support for may_goto instruction to arm64 JIT (Puranjay Mohan)

 - Fix USDT SIB argument handling in libbpf (Jiawei Zhao)

 - Allow uprobe-bpf program to change context registers (Jiri Olsa)

 - Support signed loads from BPF arena (Kumar Kartikeya Dwivedi and
   Puranjay Mohan)

 - Allow access to union arguments in tracing programs (Leon Hwang)

 - Optimize rcu_read_lock() + migrate_disable() combination where it's
   used in BPF subsystem (Menglong Dong)

 - Introduce bpf_task_work_schedule*() kfuncs to schedule deferred
   execution of BPF callback in the context of a specific task using the
   kernel’s task_work infrastructure (Mykyta Yatsenko)

 - Enforce RCU protection for KF_RCU_PROTECTED kfuncs (Kumar Kartikeya
   Dwivedi)

 - Add stress test for rqspinlock in NMI (Kumar Kartikeya Dwivedi)

 - Improve the precision of tnum multiplier verifier operation
   (Nandakumar Edamana)

 - Use tnums to improve is_branch_taken() logic (Paul Chaignon)

 - Add support for atomic operations in arena in riscv JIT (Pu Lehui)

 - Report arena faults to BPF error stream (Puranjay Mohan)

 - Search for tracefs at /sys/kernel/tracing first in bpftool (Quentin
   Monnet)

 - Add bpf_strcasecmp() kfunc (Rong Tao)

 - Support lookup_and_delete_elem command in BPF_MAP_STACK_TRACE (Tao
   Chen)

* tag 'bpf-next-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (197 commits)
  libbpf: Replace AF_ALG with open coded SHA-256
  selftests/bpf: Add stress test for rqspinlock in NMI
  selftests/bpf: Add test case for different expected_attach_type
  bpf: Enforce expected_attach_type for tailcall compatibility
  bpftool: Remove duplicate string.h header
  bpf: Remove duplicate crypto/sha2.h header
  libbpf: Fix error when st-prefix_ops and ops from differ btf
  selftests/bpf: Test changing packet data from kfunc
  selftests/bpf: Add stacktrace map lookup_and_delete_elem test case
  selftests/bpf: Refactor stacktrace_map case with skeleton
  bpf: Add lookup_and_delete_elem for BPF_MAP_STACK_TRACE
  selftests/bpf: Fix flaky bpf_cookie selftest
  selftests/bpf: Test changing packet data from global functions with a kfunc
  bpf: Emit struct bpf_xdp_sock type in vmlinux BTF
  selftests/bpf: Task_work selftest cleanup fixes
  MAINTAINERS: Delete inactive maintainers from AF_XDP
  bpf: Mark kfuncs as __noclone
  selftests/bpf: Add kprobe multi write ctx attach test
  selftests/bpf: Add kprobe write ctx attach test
  selftests/bpf: Add uprobe context ip register change test
  ...
2025-09-30 17:58:11 -07:00
Linus Torvalds
a5ba183bde hardening updates for v6.18-rc1
- Clean up usage of TRAILING_OVERLAP() (Gustavo A. R. Silva)
 
 - lkdtm: fortify: Fix potential NULL dereference on kmalloc failure
   (Junjie Cao)
 
 - Add str_assert_deassert() helper (Lad Prabhakar)
 
 - gcc-plugins: Remove TODO_verify_il for GCC >= 16
 
 - kconfig: Fix BrokenPipeError warnings in selftests
 
 - kconfig: Add transitional symbol attribute for migration support
 
 - kcfi: Rename CONFIG_CFI_CLANG to CONFIG_CFI
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Merge tag 'hardening-v6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull hardening updates from Kees Cook:
 "One notable addition is the creation of the 'transitional' keyword for
  kconfig so CONFIG renaming can go more smoothly.

  This has been a long-standing deficiency, and with the renaming of
  CONFIG_CFI_CLANG to CONFIG_CFI (since GCC will soon have KCFI
  support), this came up again.

  The breadth of the diffstat is mainly this renaming.

   - Clean up usage of TRAILING_OVERLAP() (Gustavo A. R. Silva)

   - lkdtm: fortify: Fix potential NULL dereference on kmalloc failure
     (Junjie Cao)

   - Add str_assert_deassert() helper (Lad Prabhakar)

   - gcc-plugins: Remove TODO_verify_il for GCC >= 16

   - kconfig: Fix BrokenPipeError warnings in selftests

   - kconfig: Add transitional symbol attribute for migration support

   - kcfi: Rename CONFIG_CFI_CLANG to CONFIG_CFI"

* tag 'hardening-v6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  lib/string_choices: Add str_assert_deassert() helper
  kcfi: Rename CONFIG_CFI_CLANG to CONFIG_CFI
  kconfig: Add transitional symbol attribute for migration support
  kconfig: Fix BrokenPipeError warnings in selftests
  gcc-plugins: Remove TODO_verify_il for GCC >= 16
  stddef: Introduce __TRAILING_OVERLAP()
  stddef: Remove token-pasting in TRAILING_OVERLAP()
  lkdtm: fortify: Fix potential NULL dereference on kmalloc failure
2025-09-29 17:48:27 -07:00
Kees Cook
23ef9d4397 kcfi: Rename CONFIG_CFI_CLANG to CONFIG_CFI
The kernel's CFI implementation uses the KCFI ABI specifically, and is
not strictly tied to a particular compiler. In preparation for GCC
supporting KCFI, rename CONFIG_CFI_CLANG to CONFIG_CFI (along with
associated options).

Use new "transitional" Kconfig option for old CONFIG_CFI_CLANG that will
enable CONFIG_CFI during olddefconfig.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20250923213422.1105654-3-kees@kernel.org
Signed-off-by: Kees Cook <kees@kernel.org>
2025-09-24 14:29:14 -07:00
Chenghao Duan
d0bf7cd5df riscv: bpf: Fix uninitialized symbol 'retval_off'
In the __arch_prepare_bpf_trampoline() function, retval_off is only
meaningful when save_ret is true, so the current logic is correct.
However, in the original logic, retval_off is only initialized under
certain conditions; for example, in the fmod_ret logic, the compiler is
not aware that the flags of the fmod_ret program (prog) have set
BPF_TRAMP_F_CALL_ORIG, which results in an uninitialized symbol
compilation warning.

So initialize retval_off unconditionally to fix it.

Signed-off-by: Chenghao Duan <duanchenghao@kylinos.cn>
Reviewed-by: Pu Lehui <pulehui@huawei.com>
Link: https://lore.kernel.org/r/20250922062244.822937-2-duanchenghao@kylinos.cn
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-09-23 12:29:03 -07:00
Kumar Kartikeya Dwivedi
a91ae3c893 bpf, x86: Add support for signed arena loads
Currently, signed load instructions into arena memory are unsupported.
The compiler is free to generate these, and on GCC-14 we see a
corresponding error when it happens. The hurdle in supporting them is
deciding which unused opcode to use to mark them for the JIT's own
consumption. After much thinking, it appears 0xc0 / BPF_NOSPEC can be
combined with load instructions to identify signed arena loads. Use
this to recognize and JIT them appropriately, and remove the verifier
side limitation on the program if the JIT supports them.

Co-developed-by: Puranjay Mohan <puranjay@kernel.org>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
Link: https://lore.kernel.org/r/20250923110157.18326-2-puranjay@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-09-23 12:00:22 -07:00
Hengqi Chen
fd2e081289 riscv, bpf: Sign extend struct ops return values properly
The ns_bpf_qdisc selftest triggers a kernel panic:

    Unable to handle kernel paging request at virtual address ffffffffa38dbf58
    Current test_progs pgtable: 4K pagesize, 57-bit VAs, pgdp=0x00000001109cc000
    [ffffffffa38dbf58] pgd=000000011fffd801, p4d=000000011fffd401, pud=000000011fffd001, pmd=0000000000000000
    Oops [#1]
    Modules linked in: bpf_testmod(OE) xt_conntrack nls_iso8859_1 [...] [last unloaded: bpf_testmod(OE)]
    CPU: 1 UID: 0 PID: 23584 Comm: test_progs Tainted: G        W  OE       6.17.0-rc1-g2465bb83e0b4 #1 NONE
    Tainted: [W]=WARN, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
    Hardware name: Unknown Unknown Product/Unknown Product, BIOS 2024.01+dfsg-1ubuntu5.1 01/01/2024
    epc : __qdisc_run+0x82/0x6f0
     ra : __qdisc_run+0x6e/0x6f0
    epc : ffffffff80bd5c7a ra : ffffffff80bd5c66 sp : ff2000000eecb550
     gp : ffffffff82472098 tp : ff60000096895940 t0 : ffffffff8001f180
     t1 : ffffffff801e1664 t2 : 0000000000000000 s0 : ff2000000eecb5d0
     s1 : ff60000093a6a600 a0 : ffffffffa38dbee8 a1 : 0000000000000001
     a2 : ff2000000eecb510 a3 : 0000000000000001 a4 : 0000000000000000
     a5 : 0000000000000010 a6 : 0000000000000000 a7 : 0000000000735049
     s2 : ffffffffa38dbee8 s3 : 0000000000000040 s4 : ff6000008bcda000
     s5 : 0000000000000008 s6 : ff60000093a6a680 s7 : ff60000093a6a6f0
     s8 : ff60000093a6a6ac s9 : ff60000093140000 s10: 0000000000000000
     s11: ff2000000eecb9d0 t3 : 0000000000000000 t4 : 0000000000ff0000
     t5 : 0000000000000000 t6 : ff60000093a6a8b6
    status: 0000000200000120 badaddr: ffffffffa38dbf58 cause: 000000000000000d
    [<ffffffff80bd5c7a>] __qdisc_run+0x82/0x6f0
    [<ffffffff80b6fe58>] __dev_queue_xmit+0x4c0/0x1128
    [<ffffffff80b80ae0>] neigh_resolve_output+0xd0/0x170
    [<ffffffff80d2daf6>] ip6_finish_output2+0x226/0x6c8
    [<ffffffff80d31254>] ip6_finish_output+0x10c/0x2a0
    [<ffffffff80d31446>] ip6_output+0x5e/0x178
    [<ffffffff80d2e232>] ip6_xmit+0x29a/0x608
    [<ffffffff80d6f4c6>] inet6_csk_xmit+0xe6/0x140
    [<ffffffff80c985e4>] __tcp_transmit_skb+0x45c/0xaa8
    [<ffffffff80c995fe>] tcp_connect+0x9ce/0xd10
    [<ffffffff80d66524>] tcp_v6_connect+0x4ac/0x5e8
    [<ffffffff80cc19b8>] __inet_stream_connect+0xd8/0x318
    [<ffffffff80cc1c36>] inet_stream_connect+0x3e/0x68
    [<ffffffff80b42b20>] __sys_connect_file+0x50/0x88
    [<ffffffff80b42bee>] __sys_connect+0x96/0xc8
    [<ffffffff80b42c40>] __riscv_sys_connect+0x20/0x30
    [<ffffffff80e5bcae>] do_trap_ecall_u+0x256/0x378
    [<ffffffff80e69af2>] handle_exception+0x14a/0x156
    Code: 892a 0363 1205 489c 8bc1 c7e5 2d03 084a 2703 080a (2783) 0709
    ---[ end trace 0000000000000000 ]---

The bpf_fifo_dequeue prog returns a skb which is a pointer. The pointer
is treated as a 32bit value and sign extend to 64bit in epilogue. This
behavior is right for most bpf prog types but wrong for struct ops which
requires RISC-V ABI.

So let's sign extend struct ops return values according to the function
model and RISC-V ABI([0]).

  [0]: https://riscv.org/wp-content/uploads/2024/12/riscv-calling.pdf

Fixes: 25ad10658d ("riscv, bpf: Adapt bpf trampoline to optimized riscv ftrace framework")
Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Pu Lehui <pulehui@huawei.com>
Reviewed-by: Pu Lehui <pulehui@huawei.com>
Link: https://lore.kernel.org/bpf/20250908012448.1695-1-hengqi.chen@gmail.com
2025-09-15 13:21:32 +02:00
Hengqi Chen
6798668ab1 riscv, bpf: Remove duplicated bpf_flush_icache()
The bpf_flush_icache() is done by bpf_arch_text_copy() already.
Remove the duplicated one in arch_prepare_bpf_trampoline().

Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Pu Lehui <pulehui@huawei.com>
Link: https://lore.kernel.org/bpf/20250904105119.21861-1-hengqi.chen@gmail.com
2025-09-15 13:16:55 +02:00
Alexei Starovoitov
5d87e96a49 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf after rc5
Cross-merge BPF and other fixes after downstream PR.

No conflicts.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-09-11 09:34:37 -07:00
Radim Krčmář
8a16586fa7 riscv, bpf: use lw when reading int cpu in bpf_get_smp_processor_id
emit_ld is wrong, because thread_info.cpu is 32-bit, not xlen-bit wide.
The struct currently has a hole after cpu, so little endian accesses
seemed fine.

Fixes: 2ddec2c80b ("riscv, bpf: inline bpf_get_smp_processor_id()")
Cc: stable@vger.kernel.org
Signed-off-by: Radim Krčmář <rkrcmar@ventanamicro.com>
Reviewed-by: Pu Lehui <pulehui@huawei.com>
Link: https://lore.kernel.org/r/20250812090256.757273-4-rkrcmar@ventanamicro.com
Signed-off-by: Paul Walmsley <pjw@kernel.org>
2025-09-05 15:31:20 -06:00
Radim Krčmář
ad5348c765 riscv, bpf: use lw when reading int cpu in BPF_MOV64_PERCPU_REG
emit_ld is wrong, because thread_info.cpu is 32-bit, not xlen-bit wide.
The struct currently has a hole after cpu, so little endian accesses
seemed fine.

Fixes: 19c56d4e5b ("riscv, bpf: add internal-only MOV instruction to resolve per-CPU addrs")
Cc: stable@vger.kernel.org
Signed-off-by: Radim Krčmář <rkrcmar@ventanamicro.com>
Reviewed-by: Pu Lehui <pulehui@huawei.com>
Acked-by: Björn Töpel <bjorn@kernel.org>
Tested-by: Björn Töpel <bjorn@rivosinc.com> # QEMU
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20250812090256.757273-3-rkrcmar@ventanamicro.com
Signed-off-by: Paul Walmsley <pjw@kernel.org>
2025-09-05 15:31:17 -06:00
Pu Lehui
fb7cefabae riscv, bpf: Add support arena atomics for RV64
Add arena atomics support for RMW atomics and load-acquire and
store-release instructions. Non-Zacas cmpxchg is implemented via loop,
which is not currently supported because it requires more complex
extable and loop logic.

Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Reviewed-by: Björn Töpel <bjorn@rivosinc.com>
Acked-by: Björn Töpel <bjorn@kernel.org>
Link: https://lore.kernel.org/bpf/20250719091730.2660197-10-pulehui@huaweicloud.com
2025-08-15 10:46:51 +02:00
Pu Lehui
b18f4aae6a riscv, bpf: Add ex_insn_off and ex_jmp_off for exception table handling
Add ex_insn_off and ex_jmp_off fields to struct rv_jit_context so that
add_exception_handler() does not need to be immediately followed by the
instruction to add the exception table. ex_insn_off indicates the offset
of the instruction to add the exception table, and ex_jmp_off indicates
the offset to jump over the faulting instruction. This is to prepare for
adding the exception table to atomic instructions later, because some
atomic instructions need to perform zext or other operations.

Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Reviewed-by: Björn Töpel <bjorn@rivosinc.com>
Acked-by: Björn Töpel <bjorn@kernel.org>
Link: https://lore.kernel.org/bpf/20250719091730.2660197-9-pulehui@huaweicloud.com
2025-08-15 10:46:51 +02:00
Pu Lehui
1c0196b878 riscv, bpf: Optimize cmpxchg insn with Zacas support
Optimize cmpxchg instruction with amocas.w and amocas.d
Zacas instructions.

Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Reviewed-by: Björn Töpel <bjorn@rivosinc.com>
Acked-by: Björn Töpel <bjorn@kernel.org>
Link: https://lore.kernel.org/bpf/20250719091730.2660197-8-pulehui@huaweicloud.com
2025-08-15 10:46:51 +02:00
Pu Lehui
de39d2c4cd riscv, bpf: Add Zacas instructions
Add Zacas instructions introduced by [0] to reduce code size and
improve performance of RV64 JIT.

Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Reviewed-by: Björn Töpel <bjorn@rivosinc.com>
Acked-by: Björn Töpel <bjorn@kernel.org>
Link: https://github.com/riscvarchive/riscv-zacas/releases/download/v1.0/riscv-zacas.pdf [0]
Link: https://lore.kernel.org/bpf/20250719091730.2660197-7-pulehui@huaweicloud.com
2025-08-15 10:46:51 +02:00
Pu Lehui
5090b339ee riscv, bpf: Add rv_ext_enabled macro for runtime detection extentsion
Add rv_ext_enabled macro to check whether the runtime detection
extension is enabled.

Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Reviewed-by: Björn Töpel <bjorn@rivosinc.com>
Acked-by: Björn Töpel <bjorn@kernel.org>
Link: https://lore.kernel.org/bpf/20250719091730.2660197-6-pulehui@huaweicloud.com
2025-08-15 10:46:51 +02:00
Pu Lehui
01422a4f2c riscv, bpf: Extract emit_ldx() helper
There's a lot of redundant code related to load into register
operations, let's extract emit_ldx() to make code more compact.

Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Reviewed-by: Björn Töpel <bjorn@rivosinc.com>
Acked-by: Björn Töpel <bjorn@kernel.org>
Link: https://lore.kernel.org/bpf/20250719091730.2660197-4-pulehui@huaweicloud.com
2025-08-15 10:46:51 +02:00
Pu Lehui
d92c11a6b5 riscv, bpf: Extract emit_st() helper
There's a lot of redundant code related to store from immediate
operations, let's extract emit_st() to make code more compact.

Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Reviewed-by: Björn Töpel <bjorn@rivosinc.com>
Acked-by: Björn Töpel <bjorn@kernel.org>
Link: https://lore.kernel.org/bpf/20250719091730.2660197-3-pulehui@huaweicloud.com
2025-08-15 10:46:51 +02:00
Pu Lehui
02fc01adec riscv, bpf: Extract emit_stx() helper
There's a lot of redundant code related to store from register
operations, let's extract emit_stx() to make code more compact.

Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Reviewed-by: Björn Töpel <bjorn@rivosinc.com>
Acked-by: Björn Töpel <bjorn@kernel.org>
Link: https://lore.kernel.org/bpf/20250719091730.2660197-2-pulehui@huaweicloud.com
2025-08-15 10:46:51 +02:00
Peilin Ye
db7a3822b5 bpf, riscv64: Skip redundant zext instruction after load-acquire
Currently, the verifier inserts a zext instruction right after every 8-,
16- or 32-bit load-acquire, which is already zero-extending.  Skip such
redundant zext instructions.

While we are here, update that already-obsolete comment about "skip the
next instruction" in build_body().  Also change emit_atomic_rmw()'s
parameters to keep it consistent with emit_atomic_ld_st().

Note that checking 'insn[1]' relies on 'insn' not being the last
instruction, which should have been guaranteed by the verifier; we
already use 'insn[1]' elsewhere in the file for similar purposes.
Additionally, we don't check if 'insn[1]' is actually a zext for our
load-acquire's dst_reg, or some other registers - in other words, here
we are relying on the verifier to always insert a redundant zext right
after a 8/16/32-bit load-acquire, for its dst_reg.

Acked-by: Björn Töpel <bjorn@kernel.org>
Reviewed-by: Pu Lehui <pulehui@huawei.com>
Tested-by: Björn Töpel <bjorn@rivosinc.com> # QEMU/RVA23
Signed-off-by: Peilin Ye <yepeilin@google.com>
Link: https://lore.kernel.org/r/10e90e0eab042f924d35ad0d1c1f7ca29f673152.1746588351.git.yepeilin@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-05-09 10:05:27 -07:00
Andrea Parri
8afd3170d5 bpf, riscv64: Support load-acquire and store-release instructions
Support BPF load-acquire (BPF_LOAD_ACQ) and store-release
(BPF_STORE_REL) instructions in the riscv64 JIT compiler.  For example,
consider the following 64-bit load-acquire (assuming little-endian):

  db 10 00 00 00 01 00 00  r1 = load_acquire((u64 *)(r1 + 0x0))
  95 00 00 00 00 00 00 00  exit

  opcode (0xdb): BPF_ATOMIC | BPF_DW | BPF_STX
  imm (0x00000100): BPF_LOAD_ACQ

The JIT compiler will emit an LD instruction followed by a FENCE R,RW
instruction for the above, e.g.:

  ld x7,0(x6)
  fence r,rw

Similarly, consider the following 16-bit store-release:

  cb 21 00 00 10 01 00 00  store_release((u16 *)(r1 + 0x0), w2)
  95 00 00 00 00 00 00 00  exit

  opcode (0xcb): BPF_ATOMIC | BPF_H | BPF_STX
  imm (0x00000110): BPF_STORE_REL

A FENCE RW,W instruction followed by an SH instruction will be emitted,
e.g.:

  fence rw,w
  sh x2,0(x4)

8-bit and 16-bit load-acquires are zero-extending (cf., LBU, LHU).  The
verifier always rejects misaligned load-acquires/store-releases (even if
BPF_F_ANY_ALIGNMENT is set), so the emitted load and store instructions
are guaranteed to be single-copy atomic.

Introduce primitives to emit the relevant (and the most common/used in
the kernel) fences, i.e. fences with R -> RW, RW -> W and RW -> RW.

Rename emit_atomic() to emit_atomic_rmw() to make it clear that it only
handles RMW atomics, and replace its is64 parameter to allow to perform
the required checks on the opsize (BPF_SIZE(code)).

Acked-by: Björn Töpel <bjorn@kernel.org>
Tested-by: Björn Töpel <bjorn@rivosinc.com> # QEMU/RVA23
Signed-off-by: Andrea Parri <parri.andrea@gmail.com>
Co-developed-by: Peilin Ye <yepeilin@google.com>
Signed-off-by: Peilin Ye <yepeilin@google.com>
Reviewed-by: Pu Lehui <pulehui@huawei.com>
Link: https://lore.kernel.org/r/3059c560e537ad43ed19055d2ebbd970c698095a.1746588351.git.yepeilin@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-05-09 10:05:27 -07:00
Andrea Parri
118ae46b79 bpf, riscv64: Introduce emit_load_*() and emit_store_*()
We're planning to add support for the load-acquire and store-release
BPF instructions.  Define emit_load_<size>() and emit_store_<size>()
to enable/facilitate the (re)use of their code.

Acked-by: Björn Töpel <bjorn@kernel.org>
Reviewed-by: Pu Lehui <pulehui@huawei.com>
Tested-by: Björn Töpel <bjorn@rivosinc.com> # QEMU/RVA23
Tested-by: Peilin Ye <yepeilin@google.com>
Signed-off-by: Andrea Parri <parri.andrea@gmail.com>
[yepeilin@google.com: cosmetic change to commit title]
Signed-off-by: Peilin Ye <yepeilin@google.com>
Link: https://lore.kernel.org/r/fce89473a5748e1631d18a5917d953460d1ae0d0.1746588351.git.yepeilin@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-05-09 10:05:27 -07:00
Mike Rapoport (Microsoft)
0c3beacf68 asm-generic: introduce text-patching.h
Several architectures support text patching, but they name the header
files that declare patching functions differently.

Make all such headers consistently named text-patching.h and add an empty
header in asm-generic for architectures that do not support text patching.

Link: https://lkml.kernel.org/r/20241023162711.2579610-4-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # m68k
Acked-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Tested-by: kdevops <kdevops@lists.linux.dev>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Brian Cain <bcain@quicinc.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Song Liu <song@kernel.org>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-07 14:25:15 -08:00
Andrea Parri
e59db0623f riscv, bpf: Make BPF_CMPXCHG fully ordered
According to the prototype formal BPF memory consistency model
discussed e.g. in [1] and following the ordering properties of
the C/in-kernel macro atomic_cmpxchg(), a BPF atomic operation
with the BPF_CMPXCHG modifier is fully ordered.  However, the
current RISC-V JIT lowerings fail to meet such memory ordering
property.  This is illustrated by the following litmus test:

BPF BPF__MP+success_cmpxchg+fence
{
 0:r1=x; 0:r3=y; 0:r5=1;
 1:r2=y; 1:r4=f; 1:r7=x;
}
 P0                               | P1                                         ;
 *(u64 *)(r1 + 0) = 1             | r1 = *(u64 *)(r2 + 0)                      ;
 r2 = cmpxchg_64 (r3 + 0, r4, r5) | r3 = atomic_fetch_add((u64 *)(r4 + 0), r5) ;
                                  | r6 = *(u64 *)(r7 + 0)                      ;
exists (1:r1=1 /\ 1:r6=0)

whose "exists" clause is not satisfiable according to the BPF
memory model.  Using the current RISC-V JIT lowerings, the test
can be mapped to the following RISC-V litmus test:

RISCV RISCV__MP+success_cmpxchg+fence
{
 0:x1=x; 0:x3=y; 0:x5=1;
 1:x2=y; 1:x4=f; 1:x7=x;
}
 P0                 | P1                          ;
 sd x5, 0(x1)       | ld x1, 0(x2)                ;
 L00:               | amoadd.d.aqrl x3, x5, 0(x4) ;
 lr.d x2, 0(x3)     | ld x6, 0(x7)                ;
 bne x2, x4, L01    |                             ;
 sc.d x6, x5, 0(x3) |                             ;
 bne x6, x4, L00    |                             ;
 fence rw, rw       |                             ;
 L01:               |                             ;
exists (1:x1=1 /\ 1:x6=0)

where the two stores in P0 can be reordered.  Update the RISC-V
JIT lowerings/implementation of BPF_CMPXCHG to emit an SC with
RELEASE ("rl") annotation in order to meet the expected memory
ordering guarantees.  The resulting RISC-V JIT lowerings of
BPF_CMPXCHG match the RISC-V lowerings of the C atomic_cmpxchg().

Other lowerings were fixed via 20a759df3b ("riscv, bpf: make
some atomic operations fully ordered").

Fixes: dd642ccb45 ("riscv, bpf: Implement more atomic operations for RV64")
Signed-off-by: Andrea Parri <parri.andrea@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Puranjay Mohan <puranjay@kernel.org>
Acked-by: Björn Töpel <bjorn@kernel.org>
Link: https://lpc.events/event/18/contributions/1949/attachments/1665/3441/bpfmemmodel.2024.09.19p.pdf [1]
Link: https://lore.kernel.org/bpf/20241017143628.2673894-1-parri.andrea@gmail.com
2024-10-17 17:14:48 +02:00
Pu Lehui
30a59cc797 riscv, bpf: Fix possible infinite tailcall when CONFIG_CFI_CLANG is enabled
When CONFIG_CFI_CLANG is enabled, the number of prologue instructions
skipped by tailcall needs to include the kcfi instruction, otherwise the
TCC will be initialized every tailcall is called, which may result in
infinite tailcalls.

Fixes: e63985ecd2 ("bpf, riscv64/cfi: Support kCFI + BPF on riscv64")
Signed-off-by: Pu Lehui <pulehui@huawei.com>
Acked-by: Björn Töpel <bjorn@kernel.org>
Link: https://lore.kernel.org/r/20241008124544.171161-1-pulehui@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-10-09 18:23:06 -07:00
Linus Torvalds
f557af081d RISC-V Patches for the 6.11 Merge Window, Part 1
* Support for various new ISA extensions:
     * The Zve32[xf] and Zve64[xfd] sub-extensios of the vector
       extension.
     * Zimop and Zcmop for may-be-operations.
     * The Zca, Zcf, Zcd and Zcb sub-extensions of the C extension.
     * Zawrs,
 * riscv,cpu-intc is now dtschema.
 * A handful of performance improvements and cleanups to text patching.
 * Support for memory hot{,un}plug
 * The highest user-allocatable virtual address is now visible in
   hwprobe.
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Merge tag 'riscv-for-linus-6.11-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V updates from Palmer Dabbelt:

 - Support for various new ISA extensions:
     * The Zve32[xf] and Zve64[xfd] sub-extensios of the vector
       extension
     * Zimop and Zcmop for may-be-operations
     * The Zca, Zcf, Zcd and Zcb sub-extensions of the C extension
     * Zawrs

 - riscv,cpu-intc is now dtschema

 - A handful of performance improvements and cleanups to text patching

 - Support for memory hot{,un}plug

 - The highest user-allocatable virtual address is now visible in
   hwprobe

* tag 'riscv-for-linus-6.11-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (58 commits)
  riscv: lib: relax assembly constraints in hweight
  riscv: set trap vector earlier
  KVM: riscv: selftests: Add Zawrs extension to get-reg-list test
  KVM: riscv: Support guest wrs.nto
  riscv: hwprobe: export Zawrs ISA extension
  riscv: Add Zawrs support for spinlocks
  dt-bindings: riscv: Add Zawrs ISA extension description
  riscv: Provide a definition for 'pause'
  riscv: hwprobe: export highest virtual userspace address
  riscv: Improve sbi_ecall() code generation by reordering arguments
  riscv: Add tracepoints for SBI calls and returns
  riscv: Optimize crc32 with Zbc extension
  riscv: Enable DAX VMEMMAP optimization
  riscv: mm: Add support for ZONE_DEVICE
  virtio-mem: Enable virtio-mem for RISC-V
  riscv: Enable memory hotplugging for RISC-V
  riscv: mm: Take memory hotplug read-lock during kernel page table dump
  riscv: mm: Add memory hotplugging support
  riscv: mm: Add pfn_to_kaddr() implementation
  riscv: mm: Refactor create_linear_mapping_range() for memory hot add
  ...
2024-07-20 09:11:27 -07:00
Puranjay Mohan
a5912c37fa riscv, bpf: Optimize stack usage of trampoline
When BPF_TRAMP_F_CALL_ORIG is not set, stack space for passing arguments
on stack doesn't need to be reserved because the original function is
not called.

Only reserve space for stacked arguments when BPF_TRAMP_F_CALL_ORIG is
set.

Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Pu Lehui <pulehui@huawei.com>
Link: https://lore.kernel.org/bpf/20240708114758.64414-1-puranjay@kernel.org
2024-07-08 15:44:08 +02:00
Pu Lehui
6801b0aef7 riscv, bpf: Add 12-argument support for RV64 bpf trampoline
This patch adds 12 function arguments support for riscv64 bpf trampoline.
The current bpf trampoline supports <= sizeof(u64) bytes scalar arguments [0]
and <= 16 bytes struct arguments [1]. Therefore, we focus on the situation
where scalars are at most XLEN bits and aggregates whose total size does not
exceed 2×XLEN bits in the riscv calling convention [2].

Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Björn Töpel <bjorn@rivosinc.com>
Acked-by: Björn Töpel <bjorn@kernel.org>
Acked-by: Puranjay Mohan <puranjay@kernel.org>
Link: https://elixir.bootlin.com/linux/v6.8/source/kernel/bpf/btf.c#L6184 [0]
Link: https://elixir.bootlin.com/linux/v6.8/source/kernel/bpf/btf.c#L6769 [1]
Link: https://github.com/riscv-non-isa/riscv-elf-psabi-doc/releases/download/draft-20230929-e5c800e661a53efe3c2678d71a306323b60eb13b/riscv-abi.pdf [2]
Link: https://lore.kernel.org/bpf/20240702121944.1091530-2-pulehui@huaweicloud.com
2024-07-02 16:01:30 +02:00
Pu Lehui
2382a405c5 riscv, bpf: Use bpf_prog_pack for RV64 bpf trampoline
We used bpf_prog_pack to aggregate bpf programs into huge page to
relieve the iTLB pressure on the system. We can apply it to bpf
trampoline, as Song had been implemented it in core and x86 [0]. This
patch is going to use bpf_prog_pack to RV64 bpf trampoline. Since Song
and Puranjay have done a lot of work for bpf_prog_pack on RV64,
implementing this function will be easy.

Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Björn Töpel <bjorn@rivosinc.com> #riscv
Link: https://lore.kernel.org/all/20231206224054.492250-1-song@kernel.org [0]
Link: https://lore.kernel.org/bpf/20240622030437.3973492-4-pulehui@huaweicloud.com
2024-07-01 17:10:46 +02:00
Pu Lehui
9f1e16fb1f riscv, bpf: Fix out-of-bounds issue when preparing trampoline image
We get the size of the trampoline image during the dry run phase and
allocate memory based on that size. The allocated image will then be
populated with instructions during the real patch phase. But after
commit 26ef208c20 ("bpf: Use arch_bpf_trampoline_size"), the `im`
argument is inconsistent in the dry run and real patch phase. This may
cause emit_imm in RV64 to generate a different number of instructions
when generating the 'im' address, potentially causing out-of-bounds
issues. Let's emit the maximum number of instructions for the "im"
address during dry run to fix this problem.

Fixes: 26ef208c20 ("bpf: Use arch_bpf_trampoline_size")
Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20240622030437.3973492-3-pulehui@huaweicloud.com
2024-07-01 17:10:46 +02:00
Samuel Holland
51781ce8f4
riscv: Pass patch_text() the length in bytes
patch_text_nosync() already handles an arbitrary length of code, so this
removes a superfluous loop and reduces the number of icache flushes.

Reviewed-by: Björn Töpel <bjorn@rivosinc.com>
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20240327160520.791322-6-samuel.holland@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-06-26 07:36:31 -07:00
Rafael Passos
9919c5c98c bpf: remove unused parameter in bpf_jit_binary_pack_finalize
Fixes a compiler warning. the bpf_jit_binary_pack_finalize function
was taking an extra bpf_prog parameter that went unused.
This removves it and updates the callers accordingly.

Signed-off-by: Rafael Passos <rafael@rcpassos.me>
Link: https://lore.kernel.org/r/20240615022641.210320-2-rafael@rcpassos.me
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-06-20 19:50:26 -07:00
Xiao Wang
96a27ee76f riscv, bpf: Introduce shift add helper with Zba optimization
Zba extension is very useful for generating addresses that index into array
of basic data types. This patch introduces sh2add and sh3add helpers for
RV32 and RV64 respectively, to accelerate addressing for array of unsigned
long data.

Signed-off-by: Xiao Wang <xiao.w.wang@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Björn Töpel <bjorn@kernel.org>
Link: https://lore.kernel.org/bpf/20240524075543.4050464-3-xiao.w.wang@intel.com
2024-06-03 16:45:23 +02:00
Xiao Wang
99fa63d9ca riscv, bpf: Try RVC for reg move within BPF_CMPXCHG JIT
We could try to emit compressed insn for reg move operation during CMPXCHG
JIT, the instruction compression has no impact on the jump offsets of
following forward and backward jump instructions.

Signed-off-by: Xiao Wang <xiao.w.wang@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Björn Töpel <bjorn@kernel.org>
Link: https://lore.kernel.org/bpf/20240519050507.2217791-1-xiao.w.wang@intel.com
2024-05-24 17:40:33 +02:00
Xiao Wang
e944fc8152 riscv, bpf: Use STACK_ALIGN macro for size rounding up
Use the macro STACK_ALIGN that is defined in asm/processor.h for stack size
rounding up, just like bpf_jit_comp32.c does.

Signed-off-by: Xiao Wang <xiao.w.wang@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Pu Lehui <pulehui@huawei.com>
Link: https://lore.kernel.org/bpf/20240523031835.3977713-1-xiao.w.wang@intel.com
2024-05-24 17:16:56 +02:00
Xiao Wang
c12603e76e riscv, bpf: Optimize zextw insn with Zba extension
The Zba extension provides add.uw insn which can be used to implement
zext.w with rs2 set as ZERO.

Signed-off-by: Xiao Wang <xiao.w.wang@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Pu Lehui <pulehui@huawei.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Pu Lehui <pulehui@huawei.com>
Link: https://lore.kernel.org/bpf/20240516090430.493122-1-xiao.w.wang@intel.com
2024-05-24 16:53:12 +02:00
Linus Torvalds
a49468240e Modules changes for v6.10-rc1
Finally something fun. Mike Rapoport does some cleanup to allow us to
 take out module_alloc() out of modules into a new paint shedded execmem_alloc()
 and execmem_free() so to make emphasis these helpers are actually used outside
 of modules. It starts with a no-functional changes API rename / placeholders
 to then allow architectures to define their requirements into a new shiny
 struct execmem_info with ranges, and requirements for those ranges. Archs
 now can intitialize this execmem_info as the last part of mm_core_init() if
 they have to diverge from the norm. Each range is a known type clearly
 articulated and spelled out in enum execmem_type.
 
 Although a lot of this is major cleanup and prep work for future enhancements an
 immediate clear gain is we get to enable KPROBES without MODULES now. That is
 ultimately what motiviated to pick this work up again, now with smaller goal as
 concrete stepping stone.
 
 This has been sitting on linux-next for a little less than a month, a few issues
 were found already and fixed, in particular an odd mips boot issue. Arch folks
 reviewed the code too. This is ready for wider exposure and testing.
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Merge tag 'modules-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux

Pull modules updates from Luis Chamberlain:
 "Finally something fun. Mike Rapoport does some cleanup to allow us to
  take out module_alloc() out of modules into a new paint shedded
  execmem_alloc() and execmem_free() so to make emphasis these helpers
  are actually used outside of modules.

  It starts with a non-functional changes API rename / placeholders to
  then allow architectures to define their requirements into a new shiny
  struct execmem_info with ranges, and requirements for those ranges.

  Archs now can intitialize this execmem_info as the last part of
  mm_core_init() if they have to diverge from the norm. Each range is a
  known type clearly articulated and spelled out in enum execmem_type.

  Although a lot of this is major cleanup and prep work for future
  enhancements an immediate clear gain is we get to enable KPROBES
  without MODULES now. That is ultimately what motiviated to pick this
  work up again, now with smaller goal as concrete stepping stone"

* tag 'modules-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux:
  bpf: remove CONFIG_BPF_JIT dependency on CONFIG_MODULES of
  kprobes: remove dependency on CONFIG_MODULES
  powerpc: use CONFIG_EXECMEM instead of CONFIG_MODULES where appropriate
  x86/ftrace: enable dynamic ftrace without CONFIG_MODULES
  arch: make execmem setup available regardless of CONFIG_MODULES
  powerpc: extend execmem_params for kprobes allocations
  arm64: extend execmem_info for generated code allocations
  riscv: extend execmem_params for generated code allocations
  mm/execmem, arch: convert remaining overrides of module_alloc to execmem
  mm/execmem, arch: convert simple overrides of module_alloc to execmem
  mm: introduce execmem_alloc() and execmem_free()
  module: make module_memory_{alloc,free} more self-contained
  sparc: simplify module_alloc()
  nios2: define virtual address space for modules
  mips: module: rename MODULE_START to MODULES_VADDR
  arm64: module: remove unneeded call to kasan_alloc_module_shadow()
  kallsyms: replace deprecated strncpy with strscpy
  module: allow UNUSED_KSYMS_WHITELIST to be relative against objtree.
2024-05-15 14:05:08 -07:00
Mike Rapoport (IBM)
4d7b321a9c riscv: extend execmem_params for generated code allocations
The memory allocations for kprobes and BPF on RISC-V are not placed in
the modules area and these custom allocations are implemented with
overrides of alloc_insn_page() and  bpf_jit_alloc_exec().

Define MODULES_VADDR and MODULES_END as VMALLOC_START and VMALLOC_END for
32 bit and slightly reorder execmem_params initialization to support both
32 and 64 bit variants, define EXECMEM_KPROBES and EXECMEM_BPF ranges in
riscv::execmem_params and drop overrides of alloc_insn_page() and
bpf_jit_alloc_exec().

Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2024-05-14 00:31:43 -07:00
Jakub Kicinski
6e62702feb bpf-next-for-netdev
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Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
pull-request: bpf-next 2024-05-13

We've added 119 non-merge commits during the last 14 day(s) which contain
a total of 134 files changed, 9462 insertions(+), 4742 deletions(-).

The main changes are:

1) Add BPF JIT support for 32-bit ARCv2 processors, from Shahab Vahedi.

2) Add BPF range computation improvements to the verifier in particular
   around XOR and OR operators, refactoring of checks for range computation
   and relaxing MUL range computation so that src_reg can also be an unknown
   scalar, from Cupertino Miranda.

3) Add support to attach kprobe BPF programs through kprobe_multi link in
   a session mode, meaning, a BPF program is attached to both function entry
   and return, the entry program can decide if the return program gets
   executed and the entry program can share u64 cookie value with return
   program. Session mode is a common use-case for tetragon and bpftrace,
   from Jiri Olsa.

4) Fix a potential overflow in libbpf's ring__consume_n() and improve libbpf
   as well as BPF selftest's struct_ops handling, from Andrii Nakryiko.

5) Improvements to BPF selftests in context of BPF gcc backend,
   from Jose E. Marchesi & David Faust.

6) Migrate remaining BPF selftest tests from test_sock_addr.c to prog_test-
   -style in order to retire the old test, run it in BPF CI and additionally
   expand test coverage, from Jordan Rife.

7) Big batch for BPF selftest refactoring in order to remove duplicate code
   around common network helpers, from Geliang Tang.

8) Another batch of improvements to BPF selftests to retire obsolete
   bpf_tcp_helpers.h as everything is available vmlinux.h,
   from Martin KaFai Lau.

9) Fix BPF map tear-down to not walk the map twice on free when both timer
   and wq is used, from Benjamin Tissoires.

10) Fix BPF verifier assumptions about socket->sk that it can be non-NULL,
    from Alexei Starovoitov.

11) Change BTF build scripts to using --btf_features for pahole v1.26+,
    from Alan Maguire.

12) Small improvements to BPF reusing struct_size() and krealloc_array(),
    from Andy Shevchenko.

13) Fix s390 JIT to emit a barrier for BPF_FETCH instructions,
    from Ilya Leoshkevich.

14) Extend TCP ->cong_control() callback in order to feed in ack and
    flag parameters and allow write-access to tp->snd_cwnd_stamp
    from BPF program, from Miao Xu.

15) Add support for internal-only per-CPU instructions to inline
    bpf_get_smp_processor_id() helper call for arm64 and riscv64 BPF JITs,
    from Puranjay Mohan.

16) Follow-up to remove the redundant ethtool.h from tooling infrastructure,
    from Tushar Vyavahare.

17) Extend libbpf to support "module:<function>" syntax for tracing
    programs, from Viktor Malik.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (119 commits)
  bpf: make list_for_each_entry portable
  bpf: ignore expected GCC warning in test_global_func10.c
  bpf: disable strict aliasing in test_global_func9.c
  selftests/bpf: Free strdup memory in xdp_hw_metadata
  selftests/bpf: Fix a few tests for GCC related warnings.
  bpf: avoid gcc overflow warning in test_xdp_vlan.c
  tools: remove redundant ethtool.h from tooling infra
  selftests/bpf: Expand ATTACH_REJECT tests
  selftests/bpf: Expand getsockname and getpeername tests
  sefltests/bpf: Expand sockaddr hook deny tests
  selftests/bpf: Expand sockaddr program return value tests
  selftests/bpf: Retire test_sock_addr.(c|sh)
  selftests/bpf: Remove redundant sendmsg test cases
  selftests/bpf: Migrate ATTACH_REJECT test cases
  selftests/bpf: Migrate expected_attach_type tests
  selftests/bpf: Migrate wildcard destination rewrite test
  selftests/bpf: Migrate sendmsg6 v4 mapped address tests
  selftests/bpf: Migrate sendmsg deny test cases
  selftests/bpf: Migrate WILDCARD_IP test
  selftests/bpf: Handle SYSCALL_EPERM and SYSCALL_ENOTSUPP test cases
  ...
====================

Link: https://lore.kernel.org/r/20240513134114.17575-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-13 16:41:10 -07:00
Puranjay Mohan
20a759df3b riscv, bpf: make some atomic operations fully ordered
The BPF atomic operations with the BPF_FETCH modifier along with
BPF_XCHG and BPF_CMPXCHG are fully ordered but the RISC-V JIT implements
all atomic operations except BPF_CMPXCHG with relaxed ordering.

Section 8.1 of the "The RISC-V Instruction Set Manual Volume I:
Unprivileged ISA" [1], titled, "Specifying Ordering of Atomic
Instructions" says:

| To provide more efficient support for release consistency [5], each
| atomic instruction has two bits, aq and rl, used to specify additional
| memory ordering constraints as viewed by other RISC-V harts.

and

| If only the aq bit is set, the atomic memory operation is treated as
| an acquire access.
| If only the rl bit is set, the atomic memory operation is treated as a
| release access.
|
| If both the aq and rl bits are set, the atomic memory operation is
| sequentially consistent.

Fix this by setting both aq and rl bits as 1 for operations with
BPF_FETCH and BPF_XCHG.

[1] https://riscv.org/wp-content/uploads/2017/05/riscv-spec-v2.2.pdf

Fixes: dd642ccb45 ("riscv, bpf: Implement more atomic operations for RV64")
Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
Reviewed-by: Pu Lehui <pulehui@huawei.com>
Link: https://lore.kernel.org/r/20240505201633.123115-1-puranjay@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-05-12 17:00:06 -07:00
Xiao Wang
80c5a07ae6 riscv, bpf: Fix typo in comment
We can use either "instruction" or "insn" in the comment.

Signed-off-by: Xiao Wang <xiao.w.wang@intel.com>
Reviewed-by: Pu Lehui <pulehui@huawei.com>
Link: https://lore.kernel.org/r/20240507111618.437121-1-xiao.w.wang@intel.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-05-12 16:56:43 -07:00