bpf.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Johan Almbladh <johan.almbladh@anyfinetworks.com>
To: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org
Cc: kafai@fb.com, songliubraving@fb.com, yhs@fb.com,
	john.fastabend@gmail.com, kpsingh@kernel.org, iii@linux.ibm.com,
	paul@cilium.io, yangtiezhu@loongson.cn, netdev@vger.kernel.org,
	bpf@vger.kernel.org,
	Johan Almbladh <johan.almbladh@anyfinetworks.com>
Subject: [PATCH bpf-next 10/10] bpf/tests: Add test of LDX_MEM with operand aliasing
Date: Fri,  1 Oct 2021 15:03:48 +0200	[thread overview]
Message-ID: <20211001130348.3670534-11-johan.almbladh@anyfinetworks.com> (raw)
In-Reply-To: <20211001130348.3670534-1-johan.almbladh@anyfinetworks.com>

This patch adds a set of tests of BPF_LDX_MEM where both operand registers
are the same register. Mainly testing 32-bit JITs that may load a 64-bit
value in two 32-bit loads, and must not overwrite the address register.

Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
---
 lib/test_bpf.c | 58 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/lib/test_bpf.c b/lib/test_bpf.c
index dfcbdff714b6..b9fc330fc83b 100644
--- a/lib/test_bpf.c
+++ b/lib/test_bpf.c
@@ -11133,6 +11133,64 @@ static struct bpf_test tests[] = {
 		{},
 		{ { 0, 2 } },
 	},
+	/* BPF_LDX_MEM with operand aliasing */
+	{
+		"LDX_MEM_B: operand register aliasing",
+		.u.insns_int = {
+			BPF_ST_MEM(BPF_B, R10, -8, 123),
+			BPF_MOV64_REG(R0, R10),
+			BPF_LDX_MEM(BPF_B, R0, R0, -8),
+			BPF_EXIT_INSN(),
+		},
+		INTERNAL,
+		{ },
+		{ { 0, 123 } },
+		.stack_depth = 8,
+	},
+	{
+		"LDX_MEM_H: operand register aliasing",
+		.u.insns_int = {
+			BPF_ST_MEM(BPF_H, R10, -8, 12345),
+			BPF_MOV64_REG(R0, R10),
+			BPF_LDX_MEM(BPF_H, R0, R0, -8),
+			BPF_EXIT_INSN(),
+		},
+		INTERNAL,
+		{ },
+		{ { 0, 12345 } },
+		.stack_depth = 8,
+	},
+	{
+		"LDX_MEM_W: operand register aliasing",
+		.u.insns_int = {
+			BPF_ST_MEM(BPF_W, R10, -8, 123456789),
+			BPF_MOV64_REG(R0, R10),
+			BPF_LDX_MEM(BPF_W, R0, R0, -8),
+			BPF_EXIT_INSN(),
+		},
+		INTERNAL,
+		{ },
+		{ { 0, 123456789 } },
+		.stack_depth = 8,
+	},
+	{
+		"LDX_MEM_DW: operand register aliasing",
+		.u.insns_int = {
+			BPF_LD_IMM64(R1, 0x123456789abcdefULL),
+			BPF_STX_MEM(BPF_DW, R10, R1, -8),
+			BPF_MOV64_REG(R0, R10),
+			BPF_LDX_MEM(BPF_DW, R0, R0, -8),
+			BPF_ALU64_REG(BPF_SUB, R0, R1),
+			BPF_MOV64_REG(R1, R0),
+			BPF_ALU64_IMM(BPF_RSH, R1, 32),
+			BPF_ALU64_REG(BPF_OR, R0, R1),
+			BPF_EXIT_INSN(),
+		},
+		INTERNAL,
+		{ },
+		{ { 0, 0 } },
+		.stack_depth = 8,
+	},
 	/*
 	 * Register (non-)clobbering tests for the case where a JIT implements
 	 * complex ALU or ATOMIC operations via function calls. If so, the
-- 
2.30.2


  parent reply	other threads:[~2021-10-01 13:05 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-10-01 13:03 [PATCH bpf-next 00/10] bpf/tests: Extend eBPF JIT test suite Johan Almbladh
2021-10-01 13:03 ` [PATCH bpf-next 01/10] bpf/tests: Add tests of BPF_LDX and BPF_STX with small sizes Johan Almbladh
2021-10-01 13:03 ` [PATCH bpf-next 02/10] bpf/tests: Add zero-extension checks in BPF_ATOMIC tests Johan Almbladh
2021-10-01 13:03 ` [PATCH bpf-next 03/10] bpf/tests: Add exhaustive tests of BPF_ATOMIC magnitudes Johan Almbladh
2021-10-01 13:03 ` [PATCH bpf-next 04/10] bpf/tests: Add tests to check source register zero-extension Johan Almbladh
2021-10-01 13:03 ` [PATCH bpf-next 05/10] bpf/tests: Add more tests for ALU and ATOMIC register clobbering Johan Almbladh
2021-10-01 13:03 ` [PATCH bpf-next 06/10] bpf/tests: Minor restructuring of ALU tests Johan Almbladh
2021-10-01 13:03 ` [PATCH bpf-next 07/10] bpf/tests: Add exhaustive tests of ALU register combinations Johan Almbladh
2021-10-01 13:03 ` [PATCH bpf-next 08/10] bpf/tests: Add exhaustive tests of BPF_ATOMIC " Johan Almbladh
2021-10-01 13:03 ` [PATCH bpf-next 09/10] bpf/tests: Add test of ALU shifts with operand register aliasing Johan Almbladh
2021-10-01 13:03 ` Johan Almbladh [this message]
2021-10-01 15:10 ` [PATCH bpf-next 00/10] bpf/tests: Extend eBPF JIT test suite patchwork-bot+netdevbpf

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20211001130348.3670534-11-johan.almbladh@anyfinetworks.com \
    --to=johan.almbladh@anyfinetworks.com \
    --cc=andrii@kernel.org \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=daniel@iogearbox.net \
    --cc=iii@linux.ibm.com \
    --cc=john.fastabend@gmail.com \
    --cc=kafai@fb.com \
    --cc=kpsingh@kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=paul@cilium.io \
    --cc=songliubraving@fb.com \
    --cc=yangtiezhu@loongson.cn \
    --cc=yhs@fb.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).