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authorJens Axboe <axboe@kernel.dk>2022-07-24 18:41:03 -0600
committerJens Axboe <axboe@kernel.dk>2022-07-24 18:41:03 -0600
commit4effe18fc0da27ae5d51a702841e87fa13b8a32d (patch)
tree468f353a3713c93b27e7b2c262efd747e66ff199 /arch/x86/net/bpf_jit_comp.c
parentMerge branch 'io_uring-zerocopy-send' of git://git.kernel.org/pub/scm/linux/k... (diff)
parentio_uring: ensure REQ_F_ISREG is set async offload (diff)
downloadlinux-4effe18fc0da27ae5d51a702841e87fa13b8a32d.tar.gz
linux-4effe18fc0da27ae5d51a702841e87fa13b8a32d.zip
Merge branch 'for-5.20/io_uring' into for-5.20/io_uring-zerocopy-send
* for-5.20/io_uring: (716 commits) io_uring: ensure REQ_F_ISREG is set async offload net: fix compat pointer in get_compat_msghdr() io_uring: Don't require reinitable percpu_ref io_uring: fix types in io_recvmsg_multishot_overflow io_uring: Use atomic_long_try_cmpxchg in __io_account_mem io_uring: support multishot in recvmsg net: copy from user before calling __get_compat_msghdr net: copy from user before calling __copy_msghdr io_uring: support 0 length iov in buffer select in compat io_uring: fix multishot ending when not polled io_uring: add netmsg cache io_uring: impose max limit on apoll cache io_uring: add abstraction around apoll cache io_uring: move apoll cache to poll.c io_uring: consolidate hash_locked io-wq handling io_uring: clear REQ_F_HASH_LOCKED on hash removal io_uring: don't race double poll setting REQ_F_ASYNC_DATA io_uring: don't miss setting REQ_F_DOUBLE_POLL io_uring: disable multishot recvmsg io_uring: only trace one of complete or overflow ... Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'arch/x86/net/bpf_jit_comp.c')
-rw-r--r--arch/x86/net/bpf_jit_comp.c26
1 files changed, 20 insertions, 6 deletions
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index c98b8c0ed3b8..b808c9a80d1b 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -412,16 +412,30 @@ static void emit_indirect_jump(u8 **pprog, int reg, u8 *ip)
{
u8 *prog = *pprog;
-#ifdef CONFIG_RETPOLINE
if (cpu_feature_enabled(X86_FEATURE_RETPOLINE_LFENCE)) {
EMIT_LFENCE();
EMIT2(0xFF, 0xE0 + reg);
} else if (cpu_feature_enabled(X86_FEATURE_RETPOLINE)) {
OPTIMIZER_HIDE_VAR(reg);
emit_jump(&prog, &__x86_indirect_thunk_array[reg], ip);
- } else
-#endif
- EMIT2(0xFF, 0xE0 + reg);
+ } else {
+ EMIT2(0xFF, 0xE0 + reg);
+ }
+
+ *pprog = prog;
+}
+
+static void emit_return(u8 **pprog, u8 *ip)
+{
+ u8 *prog = *pprog;
+
+ if (cpu_feature_enabled(X86_FEATURE_RETHUNK)) {
+ emit_jump(&prog, &__x86_return_thunk, ip);
+ } else {
+ EMIT1(0xC3); /* ret */
+ if (IS_ENABLED(CONFIG_SLS))
+ EMIT1(0xCC); /* int3 */
+ }
*pprog = prog;
}
@@ -1686,7 +1700,7 @@ emit_jmp:
ctx->cleanup_addr = proglen;
pop_callee_regs(&prog, callee_regs_used);
EMIT1(0xC9); /* leave */
- EMIT1(0xC3); /* ret */
+ emit_return(&prog, image + addrs[i - 1] + (prog - temp));
break;
default:
@@ -2189,7 +2203,7 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i
if (flags & BPF_TRAMP_F_SKIP_FRAME)
/* skip our return address and return to parent */
EMIT4(0x48, 0x83, 0xC4, 8); /* add rsp, 8 */
- EMIT1(0xC3); /* ret */
+ emit_return(&prog, prog);
/* Make sure the trampoline generation logic doesn't overflow */
if (WARN_ON_ONCE(prog > (u8 *)image_end - BPF_INSN_SAFETY)) {
ret = -EFAULT;