1 files changed, 49 insertions, 28 deletions

diff --git a/arch/sparc/net/bpf_jit_comp_64.c b/arch/sparc/net/bpf_jit_comp_64.c
index 222785af550b..7217d6359643 100644
--- a/arch/sparc/net/bpf_jit_comp_64.c
+++ b/arch/sparc/net/bpf_jit_comp_64.c
@@ -1425,12 +1425,12 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
 	struct bpf_prog *tmp, *orig_prog = prog;
 	struct sparc64_jit_data *jit_data;
 	struct bpf_binary_header *header;
+	u32 prev_image_size, image_size;
 	bool tmp_blinded = false;
 	bool extra_pass = false;
 	struct jit_ctx ctx;
-	u32 image_size;
 	u8 *image_ptr;
-	int pass;
+	int pass, i;
 
 	if (!prog->jit_requested)
 		return orig_prog;
@@ -1461,61 +1461,82 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
 		header = jit_data->header;
 		extra_pass = true;
 		image_size = sizeof(u32) * ctx.idx;
+		prev_image_size = image_size;
+		pass = 1;
 		goto skip_init_ctx;
 	}
 
 	memset(&ctx, 0, sizeof(ctx));
 	ctx.prog = prog;
 
-	ctx.offset = kcalloc(prog->len, sizeof(unsigned int), GFP_KERNEL);
+	ctx.offset = kmalloc_array(prog->len, sizeof(unsigned int), GFP_KERNEL);
 	if (ctx.offset == NULL) {
 		prog = orig_prog;
 		goto out_off;
 	}
 
-	/* Fake pass to detect features used, and get an accurate assessment
-	 * of what the final image size will be.
+	/* Longest sequence emitted is for bswap32, 12 instructions.  Pre-cook
+	 * the offset array so that we converge faster.
 	 */
-	if (build_body(&ctx)) {
-		prog = orig_prog;
-		goto out_off;
-	}
-	build_prologue(&ctx);
-	build_epilogue(&ctx);
+	for (i = 0; i < prog->len; i++)
+		ctx.offset[i] = i * (12 * 4);
 
-	/* Now we know the actual image size. */
-	image_size = sizeof(u32) * ctx.idx;
-	header = bpf_jit_binary_alloc(image_size, &image_ptr,
-				      sizeof(u32), jit_fill_hole);
-	if (header == NULL) {
-		prog = orig_prog;
-		goto out_off;
-	}
-
-	ctx.image = (u32 *)image_ptr;
-skip_init_ctx:
-	for (pass = 1; pass < 3; pass++) {
+	prev_image_size = ~0U;
+	for (pass = 1; pass < 40; pass++) {
 		ctx.idx = 0;
 
 		build_prologue(&ctx);
-
 		if (build_body(&ctx)) {
-			bpf_jit_binary_free(header);
 			prog = orig_prog;
 			goto out_off;
 		}
-
 		build_epilogue(&ctx);
 
 		if (bpf_jit_enable > 1)
-			pr_info("Pass %d: shrink = %d, seen = [%c%c%c%c%c%c]\n", pass,
-				image_size - (ctx.idx * 4),
+			pr_info("Pass %d: size = %u, seen = [%c%c%c%c%c%c]\n", pass,
+				ctx.idx * 4,
 				ctx.tmp_1_used ? '1' : ' ',
 				ctx.tmp_2_used ? '2' : ' ',
 				ctx.tmp_3_used ? '3' : ' ',
 				ctx.saw_frame_pointer ? 'F' : ' ',
 				ctx.saw_call ? 'C' : ' ',
 				ctx.saw_tail_call ? 'T' : ' ');
+
+		if (ctx.idx * 4 == prev_image_size)
+			break;
+		prev_image_size = ctx.idx * 4;
+		cond_resched();
+	}
+
+	/* Now we know the actual image size. */
+	image_size = sizeof(u32) * ctx.idx;
+	header = bpf_jit_binary_alloc(image_size, &image_ptr,
+				      sizeof(u32), jit_fill_hole);
+	if (header == NULL) {
+		prog = orig_prog;
+		goto out_off;
+	}
+
+	ctx.image = (u32 *)image_ptr;
+skip_init_ctx:
+	ctx.idx = 0;
+
+	build_prologue(&ctx);
+
+	if (build_body(&ctx)) {
+		bpf_jit_binary_free(header);
+		prog = orig_prog;
+		goto out_off;
+	}
+
+	build_epilogue(&ctx);
+
+	if (ctx.idx * 4 != prev_image_size) {
+		pr_err("bpf_jit: Failed to converge, prev_size=%u size=%d\n",
+		       prev_image_size, ctx.idx * 4);
+		bpf_jit_binary_free(header);
+		prog = orig_prog;
+		goto out_off;
 	}
 
 	if (bpf_jit_enable > 1)