diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2024-06-01 17:34:35 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2024-06-01 17:34:35 -0700 |
| commit | 83814698cf48ce3aadc5d88a3f577f04482ff92a (patch) | |
| tree | b35bbbdffe75f446f042aab69e752202789fcd44 /arch/powerpc/net/bpf_jit_comp32.c | |
| parent | 54bec8ed5732339438271d07376890454fa58046 (diff) | |
| parent | be2fc65d66e0406cc9d39d40becaecdf4ee765f3 (diff) | |
Merge tag 'powerpc-6.10-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
- Enforce full ordering for ATOMIC operations with BPF_FETCH
- Fix uaccess build errors seen with GCC 13/14
- Fix build errors on ppc32 due to ARCH_HAS_KERNEL_FPU_SUPPORT
- Drop error message from lparcfg guest name lookup
Thanks to Christophe Leroy, Guenter Roeck, Nathan Lynch, Naveen N Rao,
Puranjay Mohan, and Samuel Holland.
* tag 'powerpc-6.10-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc: Limit ARCH_HAS_KERNEL_FPU_SUPPORT to PPC64
powerpc/uaccess: Use YZ asm constraint for ld
powerpc/uaccess: Fix build errors seen with GCC 13/14
powerpc/pseries/lparcfg: drop error message from guest name lookup
powerpc/bpf: enforce full ordering for ATOMIC operations with BPF_FETCH
Diffstat (limited to 'arch/powerpc/net/bpf_jit_comp32.c')
| -rw-r--r-- | arch/powerpc/net/bpf_jit_comp32.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/arch/powerpc/net/bpf_jit_comp32.c b/arch/powerpc/net/bpf_jit_comp32.c index 43b97032a91c..a0c4f1bde83e 100644 --- a/arch/powerpc/net/bpf_jit_comp32.c +++ b/arch/powerpc/net/bpf_jit_comp32.c @@ -900,6 +900,15 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, u32 *fimage, struct code /* Get offset into TMP_REG */ EMIT(PPC_RAW_LI(tmp_reg, off)); + /* + * Enforce full ordering for operations with BPF_FETCH by emitting a 'sync' + * before and after the operation. + * + * This is a requirement in the Linux Kernel Memory Model. + * See __cmpxchg_u32() in asm/cmpxchg.h as an example. + */ + if ((imm & BPF_FETCH) && IS_ENABLED(CONFIG_SMP)) + EMIT(PPC_RAW_SYNC()); tmp_idx = ctx->idx * 4; /* load value from memory into r0 */ EMIT(PPC_RAW_LWARX(_R0, tmp_reg, dst_reg, 0)); @@ -953,6 +962,9 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, u32 *fimage, struct code /* For the BPF_FETCH variant, get old data into src_reg */ if (imm & BPF_FETCH) { + /* Emit 'sync' to enforce full ordering */ + if (IS_ENABLED(CONFIG_SMP)) + EMIT(PPC_RAW_SYNC()); EMIT(PPC_RAW_MR(ret_reg, ax_reg)); if (!fp->aux->verifier_zext) EMIT(PPC_RAW_LI(ret_reg - 1, 0)); /* higher 32-bit */ |